<stephane.chazelas@gmail.com>. Will eventually be contingent on
compatibility level > 43, but not there yet
+ 12/15
+ -----
+lib/sh/Makefile.in
+ - add missing dependencies for shmatch.o. Pointed out by Sergey
+ Mikhailov <sergey.mikhailov@gmail.com>
+
+ 12/16
+ -----
+{execute_cmd,subst}.c
+ - W_ASSIGNINT: remove, not used any more
+
+execute_cmd.c
+ - fix_assignment_words: don't look for `-i' option and set W_ASSIGNINT
+ flag any more; doing things a different way
+ - shell_expand_word_list: instead of using W_ASSIGNINT flag, since it
+ doesn't take into account all options that can transform values on
+ assignment (-l/-u/-c can also), go through option arguments looking
+ for options that need special handling and add them to the `opts'
+ array for make_internal_declare to use. Fixes bug with constructs
+ like `declare -al foo=(UPONE UPTWO UPTHREE)' not being lowercased on
+ assignment reported by Linda Walsh <bash@tlinx.org>
+
+ 12/18
+ -----
+lib/readline/readline.c
+ - rl_internal_char: when we read EOF on a non-empty line, check for
+ signals and invoke any readline signal handling and any application-
+ installed signal hook
+
+ 12/20
+ -----
+lib/readline/readline.c
+ - rl_internal_char: if we read EOF on a non-empty line, set c to
+ _rl_eof_char the first time through. If we read EOF the next time,
+ return EOF from readline(). If callbacks are defined, this returns
+ EOF immediately, since lastc isn't available. Fix for problem
+ most recently identified by Jiri Kukacka <jiri.kukacka@orcle.com>,
+ it has come up in the past
+
--- /dev/null
+ 2/14/2011
+ ---------
+[bash-4.2 released]
+
+ 2/15
+ ----
+lib/glob/gmisc.c
+ - fix wmatchlen and umatchlen to avoid going past the end of the
+ string on an incomplete bracket expression that ends with a
+ NUL. Partial fix for bug reported by Clark Wang <dearvoid@gmail.com>
+
+ 2/16
+ ----
+subst.h
+ - new string extract flag value: SX_WORD. Used when calling
+ extract_dollar_brace_string to skip over the word in
+ ${param op word} from parameter_brace_expand
+
+subst.c
+ - change parameter_brace_expand to add SX_WORD to flags passed to
+ extract_dollar_brace_string
+ - change parameter_brace_expand to use SX_POSIXEXP for all non-posix
+ word expansion operators that treat single quotes as special, not
+ just % and #
+ - change extract_dollar_brace_string to initialize dolbrace_state to
+ DOLBRACE_WORD if SX_WORD flag supplied and we shouldn't use
+ DOLBRACE_QUOTE. Fixes bug reported by Juergen Daubert <jue@jue.li>
+
+doc/{bash.1,bashref.texi}
+ - document the exact expansions here strings undergo
+
+ 2/17
+ ----
+lib/readline/vi_mode.c
+ - make sure that `dd', `cc', and `yy' call vidomove_dispatch from
+ rl_domove_read_callback. Fixes bug reported by Clark Wang
+ <dearvoid@gmail.com>
+
+lib/readline/callback.c
+ - make sure _rl_internal_char_cleanup is called after the
+ vi-motion callbacks (rl_vi_domove_callback) in rl_callback_read_char.
+ Companion to above fix
+
+doc/{bash.1,bashref.texi}
+ - make sure that the text describing the rhs of the == and =~
+ operators to [[ states that only the quoted portion of the pattern
+ is matched as a string
+
+ 2/18
+ ----
+lib/glob/gmisc.c
+ - better fix for umatchlen/wmatchlen: keep track of the number of
+ characters in a bracket expression as the value to increase
+ matchlen by if the bracket expression is not well-formed. Fixes
+ bug reported by Clark Wang <dearvoid@gmail.com>
+
+subst.c
+ - change expand_string_for_rhs so that it sets the W_NOSPLIT2 flag
+ in the word flags. We will not perform word splitting or quote
+ removal on the result, so we do not want to add quoted nulls if
+ we see "" or ''. Fixes bug reported by Mike Frysinger
+ <vapier@gentoo.org>
+
+ 2/19
+ ----
+variables.c
+ - new function, int chkexport(name), checks whether variable NAME is
+ exported and remakes the export environment if necessary. Returns
+ 1 if NAME is exported and 0 if not
+ - call chkexport(name) to get tzset to look at the right variable in
+ the environment when modifying TZ in sv_tz. Don't call tzset if
+ chkexport doesn't indicate that the variable is exported
+
+variables.h
+ - new extern declaration for chkexport
+
+
+{parse.y,builtins/printf.def}
+ - call sv_tz before calling localtime() when formatting time strings
+ in prompt strings or using printf. Fixes bug reported by
+ Dennis Williamson <dennistwilliamson@gmail.com>
+
+execute_cmd.c
+ - modify fix of 2/9 to add casts when those variables are passed to
+ functions; some compilers throw errors instead of warnings. Report
+ and fix from Joachim Schmitz <jojo@schmitz-digital.de>
+
+support/shobj-conf
+ - add a stanza for nsk on the Tandem from Joachim Schmitz
+ <jojo@schmitz-digital.de>
+
+{shell,lib/readline/shell}.c
+ - Tandem systems should use getpwnam (getlogin()); for some reason
+ they don't do well with using getuid(). Fix from Joachim Schmitz
+ <jojo@schmitz-digital.de>
+
+ 3/1
+ ---
+variables.c
+ - make sure that the return value from find_variable is non-null
+ before trying to use it in chkexport. Fixes bug reported by
+ Evangelos Foutras <foutrelis@gmail.com>
+
+ 3/3
+ ---
+parse.y
+ - when adding $$ to the current token buffer in read_token_word(),
+ don't xmalloc a buffer for two characters and then strcpy it, just
+ copy the characters directly into the token buffer. Fix from
+ Michael Whitten <mfwitten@gmail.com>
+
+execute_cmd.c
+ - fix expand_word_unsplit to add the W_NOSPLIT2 flag to the word to
+ be expanded, so "" doesn't add CTLNUL. Similar to fix of 2/18 to
+ expand_string_for_rhs. Fixes bug reported by Nathanael D. Noblet
+ <nathanael@gnat.ca> and Matthias Klose <doko@debian.org>
+
+parse.y
+ - fix extended_glob case of read_token_word to allocate an extra
+ space in the buffer for the next character read after the extended
+ glob specification if it's a CTLESC or CTLNUL. Report and fix from
+ Michael Witten <mfwitten@gmail.com>
+ - fix shell expansions case of read_token_word to allocate an extra
+ space in the buffer for the next character read after the shell
+ expansion if it's a CTLESC or CTLNUL. Report and fix from
+ Michael Witten <mfwitten@gmail.com>
+ - TENTATIVE: fix read_token_word to reduce the amount of buffer space
+ required to hold the translated and double-quoted value of $"..."
+ strings. Report and fix from Michael Witten <mfwitten@gmail.com>
+ - change code around got_character and got_escaped_character labels to
+ make sure that we call RESIZE_MALLOCED_BUFFER before adding the
+ CTLESC before a CTLESC or CTLNUL, and before adding the character if
+ we're not adding a CTLESC. Report and fix from
+ Michael Witten <mfwitten@gmail.com>
+
+subst.c
+ - new param flags value, PF_ASSIGNRHS, mirrors W_ASSIGNRHS, noting that
+ parameter expansion is on rhs of assignment statement. That inhibits
+ word splitting
+ - change param_expand to call string_list_dollar_at with quoted == 1
+ if PF_ASSIGNRHS is set, so it will quote IFS characters in the
+ positional parameter before separating them with the first char of
+ $IFS. This keeps the rhs from being split inappropriately. Fixes
+ bug reported by Andres Perera <andres.p@zoho.com>
+
+ 3/4
+ ---
+lib/readline/bind.c
+ - add a missing free of `names' in rl_function_dumper. Bug report
+ and fix from Michael Snyder <msnyder@vmware.com>
+
+ 3/5
+ ---
+lib/readline/rltty.c
+ - change rl_deprep_terminal so it uses fileno (stdin) for the tty fd
+ if rl_instream is not set, like rl_prep_terminal
+
+ 3/6
+ ---
+lib/readline/display.c
+ - fix rl_message to use a dynamically-allocated buffer instead of a
+ fixed-size buffer of 128 chars for the `local message prompt'. Bug
+ report and fix from Micah Cowan <micah@cowan.name>
+
+ 3/7
+ ---
+jobs.c
+ - add sentinel to wait_sigint_handler so it only sets wait_sigint_received
+ if waiting_for_child is non-zero; otherwise, it restores the old
+ SIGINT handler and sends itself the SIGINT
+ - set waiting_for_child around the calls to waitchld that use it to
+ synchronously wait for a process
+ - change logic that decides whether or not the child process blocked
+ or handled SIGINT based on whether or not waitpid returns -1/EINTR
+ and the shell receives a SIGINT and the child does not exit. If
+ the child later exits due to SIGINT, cancel the assumoption that it
+ was handled
+ - instead of testing whether or not the child exited due to SIGINT
+ when deciding whether the shell should act on a SIGINT it received
+ while waiting, test whether or not we think the child caught
+ SIGINT. If it did, we let it go (unless the shell has it trapped);
+ if it did not catch it, the shell acts on the SIGINT. Fix from
+ Linus Torvalds <torvalds@linux-foundation.org>, bug report originally
+ from Oleg Nesterov <oleg@redhat.com>
+
+ 3/8
+ ---
+shell.c
+ - initialize no_line_editing to 1 if READLINE is not defined -- we
+ can't have line editing without readline
+
+ 3/12
+ ----
+lib/readline/signals.c
+ - add SIGHUP to the set of signals readline handles
+
+lib/readline/doc/rltech.texi
+ - document that SIGHUP is now part of the set of signals readline
+ handles
+
+lib/readline/input.c
+ - if _rl_caught_signal indicates that read() was interrupted by a
+ SIGHUP or SIGTERM, return READERR or EOF as appropriate
+ - call rl_event_hook, if it's set, if call to read in rl_getc
+ returns -1/EINTR. If rl_event_hook doesn't do anything, this
+ continues the loop as before. This handles the other fatal
+ signals
+
+execute_cmd.c
+ - add a couple of QUIT; calls to execute_disk_command and
+ execute_simple_command to improve responsiveness to interrupts
+ and fatal signals
+
+input.c
+ - rearrange getc_with_restart so that the return values from read()
+ are handled right
+
+parse.y
+ - don't need to set terminate_immediately in yy_stream_get, since
+ getc_with_restart checks for terminating signals itself
+ - since readline returns READERR on SIGHUP or SIGTERM, don't need
+ to set terminate_immediately. Still doesn't handle other
+ signals well -- will have to check that some more
+
+bashline.c
+ - new function, bash_event_hook, for rl_event_hook. Just checks for
+ terminating signals and acts on them using CHECK_TERMSIG.
+ - set rl_event_hook to bash_event_hook
+
+builtins/read.def
+ - take out setting terminate_immediately; add calls to CHECK_TERMSIG
+ after read calls
+
+doc/{bash.1,bashref.texi}
+ - move the text describing the effect of negative subscripts used to
+ reference indexed array elements to the paragraphs describing
+ ${parameter[subscript]}, since that's where they are implemented.
+ Pointed out by Christopher F. A. Johnson <cfajohnson@gmail.com>
+
+arrayfunc.[ch],subst.c
+ - array_expand_index now takes a new first argument: a SHELL_VAR *
+ of the array variable being subscripted. Can be used later to fully
+ implement negative subscripts
+
+ 3/14
+ ----
+lib/glob/glob.c
+ - fix mbskipname to not turn the directory entry name into a wide char
+ string if the conversion of the pattern to a wide char string fails
+ - fix mbskipname to call skipname if either the pattern or the filename
+ can't be converted into a wide-char string
+
+lib/glob/xmbsrtowcs.c
+ - fix xdupmbstowcs2 to handle return value of 0 from mbsnrtowcs and
+ short-circuit with failure in that case. Fixes bug reported by
+ Roman Rakus <rrakus@redhat.com>
+
+ 3/15
+ ----
+bashline.c
+ - new variable, bash_filename_quote_characters to store the value
+ assigned to rl_filename_quote_characters so it can be restored
+ if changed.
+ - change bashline_reset and attempt_shell_completion to restore
+ rl_filename_quote_characters if not set to default
+
+ 3/22
+ ----
+lib/glob/glob.c
+ - wdequote_pathname falls back to udequote_pathname if xdupmbstowcs
+ fails to convert the pathname to a wide-character string
+
+lib/glob/xmbsrtowcs.c
+ - xdupmbstowcs2: change to fix problem with leading '\\' (results in
+ nms == 0, which causes it to short-circuit with failure right
+ away). Fixes bug pointed out by Werner Fink <werner@suse.de>
+ - xdupmbstowcs2: compensate for mbsnrtowcs returning 0 by taking the
+ next single-byte character and going on
+ - xdupmbstowcs2: change memory allocation to increase by WSBUF_INC
+ bytes; try to avoid calls to realloc (even if they don't actually
+ result in more memory being allocated)
+
+ 3/24
+ ----
+doc/{bash.1,bashref.texi}
+ - slightly modify BASH_SUBSHELL description based on complaint from
+ Sam Liddicott <sam@liddicott.com>
+
+ 3/25
+ ----
+trap.c
+ - change free_trap_strings to not call free_trap_string for signals
+ that are being ignored, like reset_or_restore_signal_handlers.
+ Fixes bug reported by Satoshi Takahashi <blue3waters@gmail.com>
+
+ 3/26
+ ----
+lib/readline/rltypedefs.h
+ - remove old Function/VFunction/CPFunction/CPPFunction typedefs as
+ suggested by Tom Tromey <tromey@redhat.com>
+
+lib/readline/rlstdc.h
+ - move defines for USE_VARARGS/PREFER_STDARG/PREFER_VARARGS from
+ config.h.in to here because declaration of rl_message in
+ readline.h uses the defines. This makes it hard for another packages
+ to use after the header files are installed, since config.h is not
+ one of the installed files. Suggested by Tom Tromey
+ <tromey@redhat.com>
+
+ 3/27
+ ----
+print_cmd.c
+ - change indirection_string from a static buffer to a dynamic one
+ managed by indirection_level_string(), so we don't end up truncating
+ PS4. Suggested by Dennis Williamson <dennistwilliamson@gmail.com>
+
+lib/readline/shell.c
+ - change sh_set_lines_and_columns to use static buffers instead of
+ allocating the buffers to pass to setenv/putenv
+
+lib/readline/terminal.c
+ - change _rl_get_screen_size to not call sh_set_lines_and_columns if
+ ignore_env == 0
+ - _rl_sigwinch_resize_terminal: new function to just retrieve terminal
+ size, ignoring environment
+
+lib/readline/rlprivate.h
+ - new external declaration for _rl_sigwinch_resize_terminal() (currently
+ unused)
+
+lib/readline/signals.c
+ - rl_sigwinch_handler: set _rl_caught_signal to SIGWINCH
+ - rl_sigwinch_handler: don't immediately call rl_resize_terminal; just
+ leave _rl_caught_signal set for RL_CHECK_SIGNALS to handle
+ - _rl_signal_handler: call rl_resize_terminal if sig == SIGWINCH.
+ Should fix hang when sending multiple repeated SIGWINCH reported by
+ Henning Bekel <h.bekel@googlemail.com>
+
+ 3/29
+ ----
+lib/sh/snprintf.c
+ - include math.h for any defines for isinf/isnan
+ - use code from gnulib documentation to implement isinf/isnan if they
+ are not defined
+
+configure.in
+ - don't check for isinf or isnan; c99 says they're macros anyway
+
+config.h.in
+ - remove defines for ISINF_IN_LIBC and ISNAN_IN_LIBC, no longer used
+ by snprintf.c
+
+ 4/2
+ ---
+braces.c
+ - brace_gobbler: fix to understand double-quoted command substitution,
+ since the shell understands unquoted comsubs. Fixes bug reported
+ by Michael Whitten <mfwitten@gmail.com>
+
+lib/readline/display.c
+ - include <pc.h> on MDOS
+ - get and set screen size using DJGPP-specific calls on MSDOS
+ - move cursor up clear screen using DJGPP-specific calls
+ - don't call tputs on DJGPP; there is no good terminfo support
+
+lib/readline/terminal.c
+ - include <pc.h> on MDOS
+ - get and set screen size using DJGPP-specific calls on MSDOS
+ - use DJGPP-specific initialization on MSDOS, zeroing all the
+ _rl_term_* variables
+ - don't call tputs on DJGPP; there is no good terminfo support
+ DJGPP support from Eli Zaretskii <eliz@gnu.org>
+
+ 4/6
+ ---
+
+config-top.h
+ - change DEFAULT_PATH_VALUE to something more useful and modern
+
+ 4/8
+ ---
+tests/printf2.sub
+ - make sure LC_ALL and LC_CTYPE are set so LANG assignment takes effect.
+ Reported by Cedric Arbogast <arbogast.cedric@gmail.com>
+
+ 4/11
+ ----
+include/chartypes.h
+ - fix a couple of dicey defines (though ones that don't cause any
+ compiler warnings) in IN_CTYPE_DOMAIN
+
+doc/{bashref.texi,bash.1}
+ - add note referring to duplicating file descriptors in sections
+ describing redirecting stdout and stderr and appending to stdout
+ and stderr. Suggested by Matthew Dinger <mdinger.bugzilla@gmail.com>
+
+pcomplete.c
+ - it_init_helptopics: new function to support completing on help topics,
+ not just builtins
+ - it_helptopics: new programmable completion list of help topics
+ - build list of helptopic completions in gen_action_completions on
+ demand
+
+pcomplete.h
+ - new extern declaration for it_helptopics
+
+builtins/complete.def
+ - the `helptopic' action now maps to CA_HELPTOPIC intead of CA_BUILTIN,
+ since there are more help topics than just builtins. Suggested by
+ Clark Wang <dearvoid@gmail.com>
+
+ 4/12
+ ----
+print_cmd.c
+ - fix print_arith_for_command to add a call to PRINT_DEFERRED_HEREDOCS
+ before ending the body of the command, so heredocs get attached to
+ the right command instead of to the loop. From gentoo bug 363371
+ http://bugs.gentoo.org/show_bug.cgi?id=363371
+
+execute_cmd.c
+ - change coproc_pidchk to unset the appropriate shell variables when
+ the (currently single) known coproc pid terminates
+ - cleanup and new functions to fully support multiple coprocesses when
+ and if I decide to go there
+
+ 4/13
+ ----
+print_cmd.c
+ - fix print_group_command to add a call to PRINT_DEFERRED_HEREDOCS
+ after call to make_command_string_internal before printing closing
+ `}'
+ - fix make_command_string_internal to add a call to
+ PRINT_DEFERRED_HEREDOCS after recursive call to
+ make_command_string_internal in case cm_subshell before printing
+ closing `)'
+
+ 4/14
+ ----
+print_cmd.c
+ - change overlapping strcpy in named_function_string to memmove
+
+sig.h
+ - UNBLOCK_SIGNAL: convenience define, same as UNBLOCK_CHILD, just
+ restores an old signal mask
+
+trap.c
+ - set_signal: instead of setting the signal handler to SIG_IGN while
+ installing the new trap handler, block the signal and unblock it
+ after the new handler is installed. Fixes bug reported by Roman
+ Rakus <rrakus@redhat.com>
+
+ 4/15
+ ----
+doc/{bash.1,bashref.texi}
+ - make it clear that enabling monitor mode means that all jobs run in
+ separate process groups
+
+ 4/18
+ ----
+builtins/fc.def
+ - update fix of 4/15/2010 to not take saved_command_line_count into
+ account when stepping down the history list to make sure that
+ last_hist indexes something that is valid. Fixes bug reported by
+ <piuma@piumalab.org>
+
+ 4/19
+ ----
+builtins/fc.def
+ - fc_gethnum: make sure the calculation to decide the last history
+ entry is exactly the same as fc_builtin. Fixes bug uncovered by
+ fix of 4/18 to stop seg fault
+
+ 4/22
+ ----
+lib/readline/terminal.c
+ - change _rl_enable_meta_key to set a flag indicating that it sent the
+ enable-meta sequence
+ - _rl_disable_meta_key: new function to turn off meta mode after we
+ turned it on with _rl_enable_meta_key
+
+lib/readline/rlprivate.h
+ - extern declaration for _rl_disable_meta_key
+
+configure.in
+ - if not cross-compiling, set CFLAGS_FOR_BUILD from any CFLAGS inherited
+ from the environment. Fixes HP/UX build problem reported by
+ "Daniel Richard G." <skunk@iSKUNK.ORG>
+
+ 4/26
+ ----
+config-top.h
+ - define MULTIPLE_COPROCS to 0 so the code is still disabled but easy
+ to enable via configure option or editing this file
+
+ 4/29
+ ----
+lib/sh/eaccess.c
+ - freebsd provides faccessat, with the same misfeature as their eaccess
+ and access implementations (X_OK returns true for uid==0 regardless
+ of the actual file permissions), so reorganize code to check the
+ file permissions as with eaccess. Report and fix from Johan Hattne
+ <johan.hattne@utsouthwestern.edu>
+
+ 5/2
+ ---
+doc/{bash.1,bashref.texi}
+ - add forward reference to `Pattern Matching' from `Pathname
+ Expansion', suggested by Greg Wooledge <wooledg@eeg.ccf.org>
+
+ 5/5
+ ---
+pcomplib.c
+ - the bash_completion project now distributes over 200 completions
+ for various programs, with no end in sight, so increase the value
+ of COMPLETE_HASH_BUCKETS from 32 to 128
+
+pathexp.c
+ - quote_string_for_globbing: make sure CTLESC quoting CTLESC is
+ translated into \<CTLESC> even if the flags include QGLOB_REGEXP.
+ We don't want to process the second CTLESC as a quote character.
+ Fixes bug reported by Shawn Bohrer <sbohrer@rgmadvisors.com>
+
+ 5/6
+ ---
+builtins/printf.def
+ - change PRETURN to not call fflush if ferror(stdout) is true
+ - if a call to one of the stdio functions or printstr leaves
+ ferror(stdout) true, and PRETURN is going to be called, let PRETURN
+ print the error message rather than doubling up the messages. Fixes
+ problem reported by Roman Rakus <rrakus@redhat.com>
+
+ 5/9
+ ---
+doc/{bash.1,bashref.texi}
+ - add note to the effect that lists inside compound command can be
+ terminated by newlines as well as semicolons. Suggested by
+ Roman Byshko <rbyshko@gmail.com>
+
+ 5/10
+ ----
+subst.c
+ - remove_quoted_nulls: fix problem that caused it to skip over the
+ character after a CTLNUL, which had the effect of skipping every
+ other of a series of CTLNULs. Fixes bug reported by
+ Marten Wikstrom <marten.wikstrom@keystream.se>
+
+ 5/11
+ ----
+subst.c
+ - extract_process_subst: add SX_COMMAND flag to call to
+ extract_delimited_string, since we're expanding the same sort of
+ command as command substitution. Fixes bug reported in Ubuntu
+ bug 779848
+
+ 5/12
+ ----
+configure.in
+ - set the prefer_shared and prefer_static variables appropriately
+ depending on the value of $opt_static_link
+
+aclocal.m4
+ - AC_LIB_LINKFLAGS_BODY: change to not prefer shared versions of the
+ libraries it's searching for if the prefer_shared variable is "no".
+ Fixes problem reported by Cedric Arbogast <arbogast.cedric@gmail.com>
+
+ 5/13
+ ----
+lib/readline/readline.c
+ - _rl_internal_teardown: add call to _rl_disable_meta_key to make the
+ meta key active only for the duration of the call to readline()
+ - _rl_internal_setup: move call to _rl_enable_meta_key here from
+ readline_initialize_everything so the meta key is active only for
+ the duration of the call to readline(). Suggestion from Miroslav
+ Lichvar <mlichvar@redhat.com>
+
+builtins/help.def
+ - help_builtin: change strncmp to strcmp so that `help read' no longer
+ matches `readonly'. Suggested by Clark Wang <dearvoid@gmail.com>
+
+config.h.in
+ - add define for GLIBC21, checked using jm_GLIBC21 as part of the tests
+ for libintl
+
+lib/malloc/malloc.c
+ - internal_free: don't use the cached value of memtop when deciding
+ whether or not to adjust the break and give memory back to the kernel
+ when using the GNU C library, since glibc uses sbrk for its own
+ internal purposes. From Debian bug 614815, reported by Samuel
+ Thibault <samuel.thibault@gnu.org>
+
+aclocal.m4
+ - BASH_STRUCT_WEXITSTATUS_OFFSET: change AC_RUN_IFELSE to AC_TRY_RUN
+ to avoid warning about not using AC_LANG_SOURCE
+
+ 5/14
+ ----
+bashline.[ch]
+ - two new functions, bashline_set_event_hook and bashline_reset_event_hook,
+ to set rl_event_hook to bash_event_hook and back to NULL, respectively
+ - don't set rl_event_hook unconditionally
+
+sig.c
+ - termsig_sighandler: if the shell is currently interactive and
+ readline is active, call bashline_set_event_hook to cause
+ termsig_handler to be called via bash_event_hook when the shell
+ returns from the signal handler
+
+ 5/15
+ ----
+lib/readline/display.c
+ - _rl_col_width: Mac OS X has a bug in wcwidth: it does not return 0
+ for UTF-8 combining characters. Added workaround dependent on
+ MACOSX. Fixes problem pointed out by Thomas De Contes
+ <d.l.tDecontes@free.fr>
+
+ 5/16
+ ----
+lib/readline/rlmbutil.h
+ - WCWIDTH: wrapper for wcwidth that returns 0 for Unicode combining
+ characters on systems where wcwidth is broken (e.g., Mac OS X).
+
+lib/readline/{complete,display,mbutil}.c
+ - use WCWIDTH instead of wcwidth
+
+ 5/17
+ ----
+lib/readline/display.c
+ - update_line: after computing ofd and nfd, see whether the next
+ character in ofd is a zero-width combining character. If it is,
+ back ofd and nfd up one, so the base characters no longer compare
+ as equivalent. Fixes problem reported by Keith Winstein
+ <keithw@mit.edu>
+
+lib/readline/nls.c
+ - _rl_utf8locale: new flag variable, set to non-zero if the current
+ locale is UTF-8
+ - utf8locale(): new function, returns 1 if the passed lspec (or the
+ current locale) indicates that the locale is UTF-8. Called from
+ _rl_init_eightbit
+
+lib/readline/rlprivate.h
+ - extern declaration for _rl_utf8locale
+
+locale.c
+ - locale_utf8locale: new flag variable, set to non-zero if the current
+ locale is UTF-8 (currently unused)
+ - locale_isutf8(): new function, returns 1 if the passed lspec (or the
+ current locale) indicates that the locale is UTF-8. Should be called
+ whenever the locale or LC_CTYPE value is modified
+
+aclocal.m4
+ - BASH_WCWIDTH_BROKEN: new test for whether or not wcwidth returns
+ zero-width characters like unicode combining characters as having
+ display length 1; define WCWIDTH_BROKEN in this case
+
+config.h.in
+ - WCWIDTH_BROKEN: new define
+
+lib/readline/rlmbutil.h
+ - change WCWIDTH macro to use _rl_utf8locale and the full range of
+ Unicode combining characters (U+0300-U+036F)
+
+ 5/19
+ ----
+lib/readline/rlprivate.h
+ - _rl_search_context: new member, prevc, will hold character read
+ prior to lastc
+
+lib/readline/isearch.c
+ - _rl_isearch_dispatch: if the character causes us to index into
+ another keymap, save that character in cxt->prevc
+ - _rl_isearch_dispatch: if we index into another keymap, but don't
+ find a function that's special to i-search, and the character that
+ caused us to index into that keymap would have terminated the
+ search, push back cxt->prevc and cxt->lastc to make it appear as
+ if `prevc' terminated the search, and execute lastc as a command.
+ We have to push prevc back so we index into the same keymap before
+ we read lastc. Fixes bug report from Davor Cubranic
+ <cubranic@stat.ubc.ca>
+
+ 5/20
+ ----
+expr.c
+ - expr_bind_variable: pay attention to the return value from
+ bind_variable and check whether or not we should error out due to
+ a readonly or noassign variable. Fixes bug reported by Eric
+ Blake <eblake@redhat.com>
+
+ 5/26
+ ----
+
+lib/readline/search.c
+ - include histlib.h for ANCHORED_SEARCH defines
+ - rl_history_search_flags: new variable, holds ANCHORED_SEARCH flag for
+ the duration of a history search
+ - rl_history_search_reinit: takes a new flags variable, defines whether
+ or not the search is anchored; assigned to rl_history_search_flags
+ - rl_history_serarch_reinit: if ANCHORED_SEARCH flag passed, add ^ to
+ beginning of search string; otherwise search string is unmodified
+ - rl_history_search_internal: set rl_point appropriately based on
+ whether or not rl_history_search_flags includes ANCHORED_SEARCH
+ - rl_history_substr_search_forward: new function, for non-anchored
+ substring search forward through history for string of characters
+ preceding rl_point
+ - rl_history_substr_search_backward: new function, for non-anchored
+ substring search backward through history for string of characters
+ preceding rl_point. Original code from Niraj Kulkarni
+ <kulkarniniraj14@gmail.com>
+
+lib/readline/readline.h
+ - extern declarations for rl_history_substr_search_{for,back}ward
+
+lib/readline/funmap.c
+ - history-substring-search-forward: new bindable command, invokes
+ rl_history_substr_search_forward
+ - history-substring-search-backward: new bindable command, invokes
+ rl_history_substr_search_backward
+
+lib/readline/doc/{rluser.texi,readline.3}
+ - document history-substring-search-forward and
+ history-substring-search-backward
+
+ 5/27
+ ----
+{nojobs,jobs}.c
+ - add support for DONT_REPORT_SIGTERM so that the shell doesn't print
+ a message when a job exits due to SIGTERM since that's the default
+ signal sent by the kill builtin. Suggested by Marc Herbert
+ <mark.herbert@gmail.com>
+
+config-top.h
+ - DONT_REPORT_SIGTERM: new user-modifiable setting. Commented out
+ by default
+
+ 5/28
+ ----
+lib/readline/bind.c
+ - _rl_skip_to_delim: skip to a closing double quote or other delimiter,
+ allowing backslash to quote any character, including the delimiter
+ - rl_parse_and_bind: call _rl_skip_to_delim instead of using inline
+ code
+ - rl_parse_and_bind: allow quoted strings as the values of string
+ variables. Variable values without double quotes have trailing
+ whitespace removed (which still allows embedded whitespace, for
+ better or worse). Fixes problem with string variables not matching
+ in `set' command if values happen to have trailing spaces or tabs
+ (debian bash bug #602762), but introduces slight incompatibility.
+
+ 5/29
+ ----
+doc/{bash.1,bashref.texi}
+ - clarify unset description to specify that without options, a
+ variable, then a shell function if there is no variable by that
+ name, is unset. Fixes discrepancy reported by Mu Qiao
+ <qiaomuf@gentoo.org>
+
+ 6/4
+ ----
+doc/{bash.1,bashref.texi}
+ - clarify description of LINES and COLUMNS (and checkwinsize shopt
+ option) to make it clear that only interactive shells set a
+ handler for SIGWINCH and update LINES and COLUMNS. Original
+ report submitted by Jonathan Nieder <jrnieder@gmail.com>
+
+arrayfunc.c
+ - expand_compound_array_assignment: defer expansion of words between
+ parens when performing compound assignmnt to an associative array
+ variable
+ - assign_compound_array_list: perform the same expansions when doing
+ a compound array assignment to an associative array variable as
+ when doing a straight array index assignment. The idea is that
+ foo=( [ind1]=bar [ind2]=quux)
+ is the same as
+ foo[ind1]=bar ; foo[ind2]=quux
+
+ This fixes problems with double-expansion and quote removal being
+ performed on the array indices
+
+ 6/13
+ ----
+doc/{bash.1,bashref.texi}
+ - Add a little text to make it clear that the locale determines how
+ range expressions in glob patterns are handled.
+
+
+ 6/21
+ ----
+builtins/read.def
+ - display a message and return error status if -a is used with an
+ existing associative array. Fixes bug reported by Curtis Doty
+ <curtis@greenkey.net>
+
+ 6/24
+ ----
+{jobs,nojobs}.c
+ - non-interactive shells now react to the setting of checkwinsize
+ and set LINES and COLUMNS after a foreground job exits. From a
+ suggestion by Leslie Rhorer <lrhorer@satx.rr.com>
+
+doc/{bash.1,bashref.texi}
+ - checkwinsize: remove language saying that only interactive shells
+ check the window size after each command
+
+lib/readline/histfile.c
+ - history_backupfile: new file, creates a backup history file name
+ given a filename (appending `-')
+ - history_do_write: when overwriting the history file, back it up
+ before writing. Restore backup file on a write error. Suggested
+ by chkno@chkno.net
+
+bashline.c
+ - find_cmd_name: two new arguments, return the start and end of the
+ actual text string used to find the command name, without taking
+ whitespace into account
+ - attempt_shell_completion: small changes to make sure that completion
+ attempted at the beginning of a non-empty line does not find a
+ programmable completion, even if the command name starts at point
+ - attempt_shell_completion: small change to make sure that completion
+ does not find a progcomp when in whitespace before the command
+ name
+ - attempt_shell_completion: small change to make sure that completion
+ does not find a progcomp when point is at the first character of a
+ command name, even when there is leading whitespace (similar to
+ above). Fixes problems noted by Ville Skytta <ville.skytta@iki.fi>
+
+subst.c
+ - brace_expand_word_list: since the individual strings in the strvec
+ returned by brace_expand are already allocated, don't copy them to
+ newly-allocated memory when building the WORD_LIST, just use them
+ intact
+
+locale.c
+ - locale_mb_cur_max: cache value of MB_CUR_MAX when we set or change
+ the locale to avoid a function call every time we need to read it
+
+shell.h
+ - new struct to save shell_input_line and associated variables:
+ shell_input_line_state_t
+ - add members of sh_parser_state_t to save and restore token and the
+ size of the token buffer
+
+parse.y
+ - {save,restore}_input_line_state: new functions to save and restore
+ shell_input_line and associated variables
+ - {save,restore}_parser_state: add code to save and restore the token
+ and token buffer size
+ - xparse_dolparen: call save_ and restore_input_line_state to avoid
+ problems with overwriting shell_input_line when we recursively
+ call the parser to parse a command substitution. Fixes bug
+ reported by Rui Santos <rsantos@grupopie.com>
+
+include/shmbutil.h
+ - use locale_mb_cur_max instead of MB_CUR_MAX in ADVANCE_CHAR and
+ similar macros
+
+lib/glob/smatch.c
+ - rangecmp,rangecmp_wc: change to take an additional argument, which
+ forces the use of strcoll/wscoll when non-zero. If it's 0, a new
+ variable `glob_asciirange' controls whether or not we use strcoll/
+ wscoll. If glob_asciirange is non-zero, we use straight
+ C-locale-like ordering. Suggested by Aharon Robbins
+ <arnold@skeeve.com>
+
+ 6/30
+ ----
+execute_cmd.c
+ - execute_pipeline: make sure the lastpipe code is protected by
+ #ifdef JOB_CONTROL. Fixes problem reported by Thomas Cort
+ <tcort@minix3.org>
+
+ 7/2
+ ---
+lib/readline/complete.c
+ - EXPERIMENTAL: remove setting of _rl_interrupt_immediately around
+ completion functions that touch the file system. Idea from Jan
+ Kratochvil <jan.ktratochvil@redhat.com> and the GDB development
+ team
+
+lib/readline/signals.c
+ - rl_signal_handler: if we're in callback mode, don't interrupt
+ immediately on a SIGWINCH
+
+ 7/3
+ ---
+bashline.c
+ - set_directory_hook: and its siblings are a new set of functions to
+ set, save, and restore the appropriate directory completion hook
+ - change callers to use {set,save,restore}_directory_hook instead of
+ manipulating rl_directory_rewrite_hook directly
+ - dircomplete_expand: new variable, defaults to 0, if non-zero causes
+ directory names to be word-expanded during word and filename
+ completion
+ - change {set,save,restore}_directory_hook to look at dircomplete_expand
+ and change rl_directory_completion_hook or rl_directory_rewrite_hook
+ appropriately
+
+bashline.h
+ - extern declaration for set_directory_hook so shopt code can use it
+
+ 7/6
+ ---
+builtins/shopt.def
+ - globasciiranges: new settable shopt option, makes glob ranges act
+ as if in the C locale (so b no longer comes between A and B).
+ Suggested by Aharon Robbins <arnold@skeeve.com>
+
+ 7/7
+ ---
+doc/{bash.1,bashref.texi}
+ - document new `globasciiranges' shopt option
+
+ 7/8
+ ---
+builtins/shopt.def
+ - direxpand: new settable option, makes filename completion expand
+ variables in directory names like bash-4.1 did.
+ - shopt_set_complete_direxpand: new function, does the work for the
+ above by calling set_directory_hook
+
+doc/{bash.1,bashref.texi}
+ - document new `direxpand' shopt option
+
+ 7/15
+ ----
+lib/readline/isearch.c
+ - _rl_isearch_dispatch: when adding character to search string, use
+ cxt->lastc (which we use in the switch statement) instead of c,
+ since lastc can be modified earlier in the function
+
+ 7/18
+ ----
+lib/readline/rlprivate.h
+ - _rl_search_context: add another member to save previous value of
+ (multibyte) lastc: pmb is to mb as prevc is to lastc
+
+lib/readline/isearch.c:
+ - _rl_isearch_dispatch: if a key sequence indexes into a new keymap,
+ but doesn't find any bound function (k[ind].function == 0) or is
+ bound to self-insert (k[ind].function == rl_insert), back up and
+ insert the previous character (the one that caused the index into a
+ new keymap) and arrange things so the current character is the next
+ one read, so both of them end up in the search string. Fixes bug
+ reported by Clark Wang <dearvoid@gmail.com>
+ - _rl_isearch_dispatch: a couple of efficiency improvements when adding
+ characters to the isearch string
+
+ 7/24
+ ----
+lib/readline/isearch.c
+ - _rl_isearch_dispatch: save and restore cxt->mb and cxt->pmb
+ appropriately when in a multibyte locale
+
+doc/{bash.1,bashref.texi}
+ - correct description of {x}>file (and other redirection operators
+ that allocate a file descriptor) to note the the fd range is
+ greater than or equal to 10. Fixes problem reported by
+ Christian Ullrich
+
+lib/readline/signals.c
+ - rl_signal_handler: don't interrupt immediately if in callback mode
+
+lib/readline/callback.c
+ - rl_callback_read_char: install signal handlers only when readline
+ has control in callback mode, so readline's signal handlers aren't
+ called when the application is active (e.g., between the calls to
+ rl_callback_handler_install and rl_callback_read_char). If the
+ readline signal handlers only set a flag, which the application
+ doesn't know about, the signals will effectively be ignored until
+ the next time the application calls into the readline callback
+ interface. Fixes problem of calling unsafe functions from signal
+ handlers when in callback mode reported by Jan Kratochvil
+ <jan.kratochvil@redhat.com>
+
+execute_cmd.c
+ - fix_assignment_words: when in Posix mode, the `command' builtin
+ doesn't change whether or not the command name it protects is an
+ assignment builtin. One or more instances of `command'
+ preceding `export', for instance, doesn't make `export' treat its
+ assignment statement arguments differently. Posix interpretation
+ #351
+
+doc/{bash.1,bashref.texi}
+ - document new Posix-mode behavior of `command' when preceding builtins
+ that take assignment statements as arguments
+
+builtins/printf.def
+ - printstr: if fieldwidth or precision are < 0 or > INT_MAX when
+ supplied explicitly (since we take care of the `-' separately),
+ clamp at INT_MAX like when using getint(). Fixes issue reported
+ by Ralph Coredroy <ralph@inputplus.co.uk>
+
+ 7/25
+ ----
+lib/readline/chardefs.h
+ - isxdigit: don't define if compiling with c++; declared as a c++
+ template function. Fixes bug reported by Miroslav Lichvar
+ <mlichvar@redhat.com>
+
+builtins/printf.def
+ - getint: if garglist == 0, return whatever getintmax returns (0).
+ Fixes bug reported by Ralph Coredroy <ralph@inputplus.co.uk>
+
+ 7/28
+ ----
+doc/{bash.1,bashref.texi}
+ - minor changes to the descriptions of the cd and pushd builtins
+
+lib/sh/zread.c
+ - zsyncfd: change variable holding return value from lseek to
+ off_t. Bug report and fix from Gregory Margo <gmargo@pacbell.net>
+
+ 8/1
+ ---
+expr.c
+ - don't check for division by 0 when in a context where no evaluation
+ is taking place. Fixes bug reported by dnade.ext@orange-ftgroup.com
+
+ 8/6
+ ---
+execute_cmd.c
+ - execute_command_internal: the parent branch of the subshell code
+ (where the child calls execute_in_subshell) should not close all
+ open FIFOs with unlink_fifo_list if it's part of a shell function
+ that's still executing. Fixes bug reported by Maarten Billemont
+ <lhunath@lyndir.com>
+
+ 8/9
+ ---
+builtins/common.c
+ - get_exitstat: return EX_BADUSAGE (2) on a non-numeric argument
+
+builtins/return.def
+ - return_builtin: just call get_exitstat to get the return status,
+ let it handle proper parsing and handling of arguments. Fixes
+ issue most recently raised by Linda Walsh <bash@tlinx.org>.
+ Reverses change from 9/11/2008 (see above)
+
+ 8/16
+ ----
+doc/{bash.1,bashref.texi}
+ - clean up `set -e' language to make it clearer that any failure of
+ a compound command will cause the shell to exit, not just subshells
+ and brace commands
+
+ 8/17
+ ----
+configure.in
+ - make the various XXX_FOR_BUILD variables `precious' to autoconf to
+ avoid stale data
+ - change how CC_FOR_BUILD is initialized when cross-compiling and not,
+ but do not change behavior
+ - initialize CFLAGS_FOR_BUILD to -g when cross-compiling
+ - initialize LIBS_FOR_BUILD to $(LIBS) when not cross-compiling, empty
+ when cross-compiling
+ - create AUTO_CFLAGS variable to hold basic CFLAGS defaults; used when
+ CFLAGS not inherited from environment (like effect of old
+ auto_cflags variable)
+ - substitute LIBS_FOR_BUILD into output Makefiles
+ [changes inspired by bug report from Nathan Phillip Brink
+ <ohnobinki@ohnopublishing.net> -- gentoo bug 378941]
+
+builtins/Makefile.in
+ - substitute LIBS_FOR_BUILD from configure, not strictly initialized
+ to $(LIBS)
+
+ 8/27
+ ----
+doc/{bash.1,bashref.texi}
+ - minor changes to the here string description to clarify the
+ expansions performed on the word
+
+support/shobj-conf
+ - handle compilation on Lion (Mac OS X 10.7/darwin11) with changes
+ to darwin stanzas. Fixes readline bug reported by Vincent
+ Sheffer <vince.sheffer@apisphere.com>
+
+lib/sh/strtrans.c
+ - ansic_wshouldquote: check a string with multi-byte characters for
+ characters that needs to be backslash-octal escaped for $'...'
+ - ansic_shouldquote: if is_basic fails for one character, let
+ ansic_wshouldquote examine the rest of the string and return what
+ it returns. From a patch sent by Roman Rakus <rrakus@redhat.com>
+
+ 8/30
+ ----
+lib/sh/strtrans.c
+ - ansic_quote: changes to quote (or not) multibyte characters. New
+ code converts them to wide characters and uses iswprint to check
+ valid wide chars. From a patch sent by Roman Rakus
+ <rrakus@redhat.com>
+
+ 9/7
+ ---
+lib/sh/shquote.c
+ - sh_backslash_quote: change to be table-driven so we can use a
+ different table if we want to
+ - sh_backslash_quote: takes a second char table[256] argument;
+
+externs.h
+ - sh_backslash_quote: add second argument to function prototype
+
+bashline.c,braces.c,parse.y,builtins/printf.def
+ - change callers of sh_backslash_quote to add second argument
+
+bashline.c
+ - filename_bstab: table of characters to pass to sh_backslash_quote;
+ characters with value 1 will be backslash-quoted
+ - set_filename_bstab: turn on characters in filename backslash-quote
+ table according to passed string argument
+ - call set_filename_bstab every time rl_filename_quote_characters is
+ assigned a value
+ - bash_quote_filename: call sh_backslash_quote with filename_bstab
+ as second argument. This allows other characters in filenames to
+ be quoted without quoting, for instance, a dollar sign in a shell
+ variable reference
+
+ 9/8
+ ---
+bashline.c
+ - complete_fullquote: new variable, controls table passed to
+ sh_backslash_quote. If non-zero (the default), the standard set
+ of shell metacharacters -- as in bash versions up to and including
+ bash-4.2 -- gets backslash-quoted by the completion code. If zero,
+ sh_backslash_quote gets the table with the characters in the
+ variable reference removed, which means they are removed from the
+ set of characters to be quoted in filenames
+
+ 9/10
+ ----
+bashline.c
+ - bash_filename_stat_hook: new function, designed to expand variable
+ references in filenames before readline passes them to stat(2)
+ to determine whether or not they are a directory
+
+ 9/15
+ ----
+builtins/declare.def
+ - if assign_array_element fails due to a bad (or empty) subscript, mark
+ it as an assignment error and don't attempt any further processing
+ of that declaration. Fixes segfault bug reported by Diego Augusto
+ Molina <diegoaugustomolina@gmail.com>
+
+ 9/19
+ ----
+expr.c
+ - exppower: replace the simple exponentiation algorithm with an
+ implementation of exponentiation by squaring. Inspired by report
+ from Nicolas ARGYROU <nargy@yahoo.com>
+
+bashline.c
+ - bash_quote_filename: check for rtext being non-null before
+ dereferencing it
+ - set_saved_history: operate_and_get_next assumes that the previous
+ line was added to the history, even when the history is stifled and
+ at the max number of entries. If it wasn't, make sure the history
+ number is incremented properly. Partial fix for bug reported by
+ gregrwm <backuppc-users@whitleymott.net>
+
+doc/{bash.1,bashref.texi},lib/readline/doc/{hsuser,rluser}.texi
+ - minor editorial changes inspired by suggestions from
+ Roger Zauner <rogerx.oss@gmail.com>
+
+ 9/20
+ ----
+lib/intl/localealias.c
+ - read_alias_file: close resource leak (fp) when returning on error
+
+ 9/22
+ ----
+execute_command.c
+ - execute_intern_function: implement Posix interpretation 383 by making
+ it an error to define a function with the same name as a special
+ builtin when in Posix mode.
+ http://austingroupbugs.net/view.php?id=383#c692
+
+ 9/25
+ ----
+doc/{bash.1,bashref.texi}
+ - formatting and some content changes from Benno Schulenberg
+ <bensberg@justemail.net>
+ - document new posix-mode behavior from interp 383 change of 9/22
+
+ 9/30
+ ----
+execute_cmd.c
+ - shell_execve: add strerror to error message about executable file
+ that shell can't execute as a shell script. From suggestion by
+ daysleeper <daysleeper@centrum.cz>
+
+ 10/1
+ ----
+bashhist.c
+ - maybe_add_history: act as if literal_history is set when parser_state
+ includes PST_HEREDOC, so we save the bodies of here-documents just
+ as they were entered. Fixes bug reported by Jonathan Wakely
+ <bugs@kayari.org>
+ - bash_add_history: make sure that the second and subsequent lines of
+ a here document don't have extra newlines or other delimiting
+ chars added, since they have the trailing newline preserved, when
+ `lithist' is set and history_delimiting_chars isn't called
+
+execute_cmd.c
+ - execute_command_internal: avoid fd exhaustion caused by using
+ process substitution in loops inside shell functions by using
+ copy_fifo_list and close_new_fifos (). Fixes debian bash bug
+ 642504
+
+lib/readline/complete.c
+ - new variable, rl_filename_stat_hook, used by append_to_match. If
+ filename completion is desired, and rl_filename_stat_hook points
+ to a function, call that function to expand the filename in an
+ application-specific way before calling stat.
+
+bashline.c
+ - bash_default_completion: if variable completion returns a single
+ match, use bash_filename_stat_hook and file_isdir to determine
+ whether or not the variable name expands to a directory. If it
+ does, set the filename_append_character to `/'. This is not
+ perfect, so we will see how it works out. Adds functionality
+ requested by Peter Toft <pto@linuxbog.dk> and Patrick Pfeifer
+ <patrick@pfeifer.de>
+ - rl_filename_stat_hook: assigned bash_filename_stat_hook, so things
+ like $HOME/Downloads (after completion) have a slash appended.
+ In general, this causes the stat hook to be called whenever
+ filename completion is appended. Adds functionality requested by
+ Patrick Pfeifer <patrick@pfeifer.de>
+
+lib/readline/readline.h
+ - new extern declaration for rl_filename_stat_hook
+
+lib/readline/doc/rltech.texi
+ - rl_directory_rewrite_hook: now documented
+ - rl_filename_stat_hook: document
+
+pcomplete.c
+ - gen_action_completions: in the CA_DIRECTORY case, turn off
+ rl_filename_completion_desired if it was off before we called
+ rl_filename_completion_function and we didn't get any matches.
+ Having it on causes readline to quote the matches as if they
+ were filenames. Adds functionality requested by many,
+ including Clark Wang <dearvoid@gmail.com>
+
+assoc.[ch]
+ - assoc_replace: new function, takes the same arguments as
+ assoc_insert, but returns the old data instead of freeing it
+ - assoc_insert: if the object returned by hash_insert doesn't have
+ the same value for its key as the key passed as an argument, we
+ are overwriting an existing value. In this case, we can free the
+ key. Fixes bug reported by David Parks <davidparks21@yahoo.com>
+
+ 10/5
+ ----
+print_cmd.c
+ - indirection_level_string: small change to only re-enable `x'
+ option after calling decode_prompt_string if it was on before. In
+ normal mode, it will be, but John Reiser <jreiser@bitwagon.com>
+ has a novel use for that code in conjunction with a pre-loaded
+ shared library that traces system call usage in shell scripts
+
+ 10/10
+ -----
+Makefile.in
+ - Fix from Mike Frysinger <vapier@gentoo.org> to avoid trying to
+ build y.tab.c and y.tab.h with two separate runs of yacc if
+ parse.y changes. Problem with parallel makes
+ - Fix from Mike Frysinger <vapier@gentoo.org> to avoid subdirectory
+ builds each trying to make version.h (and all its dependencies)
+
+lib/sh/Makefile.in
+ - remove some dependencies on version.h where it doesn't make sense
+
+variables.c
+ - initialize_shell_variables: while reading the environment, a shell
+ running in posix mode now checks for SHELLOPTS being readonly (it
+ gets set early on in main()) before trying to assign to it. It
+ saves an error message and the variable gets parsed as it should.
+ Fixes bug reported by Len Giambrone <Len.Giambrone@intersystems.com>
+
+ 10/14
+ -----
+doc/{bash.1,bashref.texi}
+ - add to the "duplicating file descriptors" description that >&word
+ doesn't redirect stdout and stderr if word expands to `-'
+ - add to the "appending standard output and standard error"
+ description a note that >&word, where word is a number or `-',
+ causes other redirection operators to apply for sh and Posix
+ compatibility reasons. Suggested by Greg Wooledge
+ <wooledg@eeg.ccf.org>
+
+ 10/15
+ -----
+pcomplete.c
+ - change pcomp_filename_completion_function to only run the filename
+ dequoting function in the cases (as best as it can figure) where
+ readline won't do it via rl_filename_completion_function. Based
+ on reports from <lolilolicon@gmail.com>
+
+ 10/19
+ -----
+bashline.c
+ - attempt_shell_completion: add call to set_directory_hook() to make
+ sure the rewrite functions are correct. It's cheap and doesn't
+ hurt
+ - command_word_completion_function: if completing a command name that
+ starts with `.' or `..', temporarily suppress the effects of the
+ `direxpand' option and restore the correct value after calling
+ rl_filename_completion_function. If it's enabled, the directory
+ name will be rewritten and no longer match `./' or `../'. Fixes
+ problem reported by Michael Kalisz <michael@kalisz.homelinux.net>
+
+ 10/22
+ -----
+builtins/history.def
+ - push_history: make sure remember_on_history is enabled before we
+ try to delete the last history entry -- the `history -s' command
+ might not have been saved. Fixes bug reported by
+ lester@vmw-les.eng.vmware.com
+
+lib/readline/complete.c
+ - rl_callback_read_char: add calls to a macro CALLBACK_READ_RETURN
+ instead of straight return; add same call at end of function.
+ Placeholder for future work in deinstalling signal handlers when
+ readline is not active
+
+ 10/25
+ -----
+expr.c
+ - exp2: catch arithmetic overflow when val1 == INTMAX_MIN and val2 == -1
+ for DIV and MOD and avoid SIGFPE. Bug report and pointer to fix
+ from Jaak Ristioja <jaak.ristioja@cyber.ee>
+ - expassign: same changes for arithmetic overflow for DIV and MOD
+
+ 10/28
+ -----
+subst.c
+ - parameter_brace_expand: allow pattern substitution when there is an
+ expansion of the form ${var/} as a no-op: replacing nothing with
+ nothing
+ - parameter_brace_patsub: don't need to check for PATSUB being NULL;
+ it never is
+
+flags.c
+ - if STRICT_POSIX is defined, initialize history_expansion to 0, since
+ history expansion (and its treatment of ! within double quotes) is
+ not a conforming posix environment. From austin-group issue 500
+
+lib/readline/histexpand.c
+ - history_expand: when processing a string within double quotes
+ (DQUOTE == 1), make the closing double quote inhibit history
+ expansion, as if the word were outside double quotes. In effect,
+ we assume that the double quote is followed by a character in
+ history_no_expand_chars. tcsh and csh seem to do this. This
+ answers a persistent complaint about history expansion
+
+ 10/29
+ -----
+make_cmd.c
+ - make_arith_for_command: use skip_to_delim to find the next `;'
+ when breaking the string between the double parens into three
+ separate components instead of a simple character loop. Fixes
+ bug reported by Dan Douglas <ormaaj@gmail.com>
+
+ 11/2
+ ----
+Makefile.in
+ - make libbuiltins.a depend on builtext.h to serialize its creation
+ and avoid conflict between multiple invocations of mkbuiltins.
+ Fix from Mike Frysinger <vapier@gentoo.org>
+
+ 11/5
+ ----
+findcmd.c
+ - user_command_matches: if stat(".", ...) returns -1, set st_dev
+ and st_ino fields in dotinfo to 0 to avoid same_file matches
+ - find_user_command_in_path: check stat(2) return the same way
+
+lib/glob/glob.c
+ - glob_vector: don't call strlen(pat) without checking pat == 0
+ - glob_dir_to_array: make sure to free `result' and all allocated
+ members before returning error due to malloc failure
+ - glob_vector: make sure to free `nextname' and `npat' on errors
+ (mostly when setting lose = 1)
+ - glob_vector: if flags & GX_MATCHDIRS but not GX_ALLDIRS, make
+ sure we free `subdir'
+ - glob_filename: when expanding ** (GX_ALLDIRS), make sure we
+ free temp_results (return value from glob_vector)
+
+lib/glob/xmbsrtowcs.c
+ - xdupmbstowcs: fix call to realloc to use sizeof (char *) instead
+ of sizeof (char **) when assigning idxtmp
+
+execute_cmd.c
+ - print_index_and_element: return 0 right away if L == 0
+ - is_dirname: fix memory leak by freeing `temp'
+ - time_command: don't try to deref NULL `command' when assigning
+ to `posix_time'
+ - shell_execve: null-terminate `sample' after READ_SAMPLE_BUF so it's
+ terminated for functions that expect that
+
+builtins/read.def
+ - read_builtin: don't call bind_read_variable with a potentially-null
+ string
+
+pcomplete.c
+ - gen_command_matches: don't call dispose_word_desc with a NULL arg
+ - gen_compspec_completions: fix memory leak by freeing `ret' before
+ calling gen_action_completions (tcs, ...). happens when
+ performing directory completion as default and no completions
+ have been generated
+ - gen_progcomp_completions: make sure to set foundp to 0 whenever
+ returning NULL
+ - it_init_aliases: fix memory leak by freeing alias_list before
+ returning
+
+bashline.c
+ - command_word_completion_function: don't call restore_tilde with a
+ NULL directory_part argument
+ - bash_directory_expansion: bugfix: don't throw away results of
+ rl_directory_rewrite_hook if it's set and returns non-zero
+ - bind_keyseq_to_unix_command: free `kseq' before returning error
+
+arrayfunc.c
+ - assign_array_element_internal: make sure `akey' is freed if non-null
+ before returning error
+ - assign_compound_array_list: free `akey' before returning error
+ - array_value_internal: free `akey' before returning error
+ - unbind_array_element: free `akey' before returning error
+
+subst.c
+ - array_length_reference: free `akey' before returning error in case
+ of expand_assignment_string_to_string error
+ - array_length_reference: free `akey' after call to assoc_reference
+ - skip_to_delim: if skipping process and command substitution, free
+ return value from extract_process_subst
+ - parameter_brace_substring: free `val' (vtype == VT_VARIABLE) before
+ returning if verify_substring_values fails
+ - parameter_brace_expand: remove two duplicate lines that allocate
+ ret in parameter_brace_substring case
+ - parameter_brace_expand: convert `free (name); name = xmalloc (...)'
+ to use `xrealloc (name, ...)'
+ - parameter_brace_expand: free `name' before returning when handling
+ ${!PREFIX*} expansion
+ - split_at_delims: fix memory leak by freeing `d2' before returning
+
+redir.c
+ - redirection_error: free `filename' if the redirection operator is
+ REDIR_VARASSIGN by assigning allocname
+
+eval.c
+ - send_pwd_to_eterm: fix memory leak by freeing value returned by
+ get_working_directory()
+
+builtins/cd.def
+ - change_to_directory: fix memory leak by freeing return value from
+ resetpwd()
+ - cd_builtin: fix memory leak by freeing value returned by dirspell()
+ - cd_builtin: fix memory leak by freeing `directory' if appropriate
+ before overwriting with return value from resetpwd()
+
+builtins/type.def
+ - describe_command: free `full_path' before overwriting it with return
+ value from sh_makepath
+
+builtins/complete.def
+ - compgen_builtin: fix memory leak by calling strlist_dispose (sl)
+ before overwriting sl with return value from completions_to_stringlist
+
+builtins/hash.def
+ - list_hashed_filename_targets: fix memory leak by freeing `target'
+
+make_cmd.c
+ - make_arith_for_command: free `init', `test', and `step' before
+ returning error on parse error
+
+jobs.c
+ - initialize_job_control: don't call move_to_high_fd if shell_tty == -1
+
+general.c
+ - check_dev_tty: don't call close with an fd < 0
+ - legal_number: deal with NULL `string' argument, return invalid
+
+lib/sh/fmtulong.c
+ - fmtulong: if the `base' argument is invalid, make sure we index
+ buf by `len-1' at maximum
+
+print_cmd.c
+ - print_deferred_heredocs: don't try to dereference a NULL `cstring'
+ - cprintf: make sure to call va_end (args)
+
+variables.c
+ - push_dollar_vars: fix call to xrealloc to use sizeof (WORD_LIST *)
+ instead of sizeof (WORD_LIST **)
+
+lib/sh/zmapfd.c
+ - zmapfd: if read returns error, free result and return -1 immediately
+ instead of trying to reallocate it
+
+ 11/6
+ ----
+execute_cmd.c
+ - cpl_reap: rewrote to avoid using pointer after freeing it; now builds
+ new coproc list on the fly while traversing the old one and sets the
+ right values for coproc_list when done
+
+ 11/12
+ -----
+builtins/set.def
+ - if neither -f nor -v supplied, don't allow a readonly function to
+ be implicitly unset. Fixes bug reported by Jens Schmidt
+ <jens.schmidt35@arcor.de>
+
+lib/readline/callback.c
+ - change CALLBACK_READ_RETURN to clear signal handlers before returning
+ from rl_callback_read_char so readline's signal handlers aren't
+ installed when readline doesn't have control. Idea from Jan
+ Kratochvil <jan.ktratochvil@redhat.com> and the GDB development
+ team
+
+pcomplete.h
+ - COPT_NOQUOTE: new complete/compgen option value
+
+builtins/complete.def
+ - noquote: new complete/compgen option; will be used to disable
+ filename completion quoting
+
+pcomplete.c
+ - pcomp_set_readline_variables: pay attention to COPT_NOQUOTE; turns
+ of rl_filename_quoting_desired if set; turns it on if unset (value
+ is inverted, since default is on)
+
+doc/bash.1,lib/readline/doc/rluser.texi
+ - document new -o noquote option to complete/compgen/compopt
+
+pathexp.c
+ - quote_string_for_globbing: if QGLOB_REGEXP, make sure characters
+ between brackets in an ERE bracket expression are not inappropriately
+ quoted with backslashes. This is a pretty substantial change,
+ should be stressed when opening bash up for alpha and beta tests.
+ Fixes bug pointed out by Stephane Chazleas
+ <stephane_chazelas@yahoo.fr>
+
+doc/{bash.1,bashref.texi}
+ - document that regexp matches can be inconsistent when quoting
+ characters in bracket expressions, since usual quoting characters
+ lose their meaning within brackets
+ - note that regular expression matching when the pattern is stored
+ in a shell variable which is quoted for expansion causes string
+ matching
+
+redir.h
+ - RX_SAVEFD: new flag value; notes that a redirection denotes an
+ fd used to save another even if it's not >= SHELL_FD_BASE
+
+redir.c
+ - do_redirection_internal: when deciding whether or not to reset the
+ close-on-exec flag on a restored file descriptor, trust the value
+ of redirect->flags & RX_SAVCLEXEC even if the fd is < SHELL_FD_BASE
+ if the RX_SAVEFD flag is set
+ - add_undo_redirect: set the RX_SAVEFD flag if the file descriptor
+ limit is such that the shell can't duplicate to a file descriptor
+ >= 10. Fixes a limitation that tripped a coreutils test reported
+ by Paul Eggert <eggert@cs.ucla.edu>
+
+ 11/19
+ -----
+doc/{bash.1,bashref.texi},lib/readline/doc/hsuser.texi
+ - make it clear that bash runs HISTFILESIZE=$HISTSIZE after reading
+ the startup files
+ - make it clear that bash runs HISTSIZE=500 after reading the
+ startup files
+ - make it clear that setting HISTSIZE=0 causes commands to not be
+ saved in the history list
+ - make it clear that setting HISTFILESIZE=0 causes the history file
+ to be truncated to zero size
+
+variables.c
+ - sv_histsize: change so setting HISTSIZE to a value less than 0
+ causes the history to be `unstifled'
+ - sv_histsize: change so setting HISTFILESIZE to a value less than 0
+ results in no file truncation
+ - make it clear that numeric values less than 0 for HISTFILESIZE or
+ HISTSIZE inhibit the usual functions
+
+ 11/23
+ -----
+parse.y
+ - save_input_line_state: add missing `return ls' at the end, since the
+ function is supposed to return its argument. Pointed out by
+ Andreas Schwab <schwab@linux-m68k.org>
+
+builtins/read.def
+ - skip over NUL bytes in input, as most modern shells seem to. Bug
+ report by Matthew Story <matt@tablethotels.com>
+
+lib/readline/vi_mode.c
+ - rl_vi_replace: set _rl_vi_last_key_before_insert to invoking key
+
+ 11/25
+ -----
+builtins/read.def
+ - read_builtin: if xrealloc returns same pointer as first argument,
+ don't bother with the remove_unwind_protect/add_unwind_protect pair
+ - read_builtin: set a flag (`reading') around calls to zread/zreadc
+ and readline()
+ - sigalrm: change to set flag (`sigalrm_seen') and only longjmp if
+ currently in read(2) (reading != 0)
+ - CHECK_ALRM: new macro, checks sigalrm_seen and longjmps if non-zero,
+ behavior of old SIGALRM catching function
+ - read_builtin: call CHECK_ALRM in appropriate places while reading
+ line of input. Fixes bug reported by Pierre Gaston
+ <pierre.gaston@gmail.com>
+
+lib/readline/vi_mode.c
+ - rl_vi_replace: initialize characters before printing characters in
+ vi_replace_keymap to their default values in vi_insertion_keymap,
+ since we're supposed to be in insert mode replacing characters
+ - rl_vi_replace: call rl_vi_start_inserting to set last command to
+ `R' for undo
+ - rl_vi_replace: set _rl_vi_last_key_before_insert to `R' for future
+ use by _rl_vi_done_inserting
+ - vi_save_insert_buffer: new function, broke out code that copies text
+ into vi_insert_buffer from _rl_vi_save_insert
+ - _rl_vi_save_replace: new function, saves text modified by
+ rl_vi_replace (using current point and vi_replace_count to figure
+ it out) to vi_replace_buffer
+ - _rl_vi_save_insert: call vi_save_insert_buffer
+ - _rl_vi_done_inserting: if _rl_vi_last_key_before_insert == 'R', call
+ _rl_vi_save_replace to save text modified in replace mode (uses
+ vi_save_insert_buffer)
+ - _rl_vi_replace_insert: new function, replaces the number of chars
+ in vi_insert_buffer after rl_point with contents ov vi_insert_buffer
+ - rl_vi_redo: call _rl_vi_replace_insert if last command == 'R' and
+ there's something in vi_insert_buffer. Fixes bug with `.' not
+ redoing the most recent `R' command, reported by Geoff Clare
+ <g.clare@opengroup.org> in readline area on savannah
+
+ 11/26
+ -----
+lib/readline/rlprivate.h
+ - RL_SIG_RECEIVED(): evaluate to non-zero if there is a pending signal
+ to be handled
+ - RL_SIGINT_RECEIVED(): evaluate to non-zero if there is a pending
+ SIGINT to be handled
+
+lib/readline/complete.c
+ - remove all mention of _rl_interrupt_immediately
+ - rl_completion_matches: check RL_SIG_RECEIVED after each call to
+ the entry function, call RL_CHECK_SIGNALS if true to handle the
+ signal
+ - rl_completion_matches: if RL_SIG_RECEIVED evaluates to true, free
+ and zero out the match_list this function allocated
+ - rl_completion_matches: if the completion entry function is
+ rl_filename_completion_function, free the contents of match_list,
+ because that function does not keep state and will not free the
+ entries; avoids possible memory leak pointed out by
+ Garrett Cooper <yanegomi@gmail.com>
+ - gen_completion_matches: if RL_SIG_RECEIVED evalutes to true after
+ calling rl_attempted_completion_function, free the returned match
+ list and handle the signal with RL_CHECK_SIGNALS; avoids
+ possible memory leak pointed out by Garrett Cooper
+ <yanegomi@gmail.com>
+ - gen_completion_matches: if RL_SIG_RECEIVED evaluates to true after
+ calling rl_completion_matches, free the returned match list and
+ handle the signal with RL_CHECK_SIGNALS
+
+lib/readline/util.c
+ - rl_settracefp: new utility function to set the tracing FILE *
+
+lib/readline/signals.c
+ - _rl_sigcleanup: pointer to a function that will be called with the
+ signal and a void * argument from _rl_handle_signal
+ - _rl_sigcleanarg: void * that the rest of the code can set to have
+ passed to the signal cleanup function
+ - _rl_handle_signal: if _rl_sigcleanup set, call as
+ (*_rl_sigcleanup) (sig, _rl_sigcleanarg)
+
+lib/readline/rlprivate.h
+ - extern declarations for _rl_sigcleanup and _rl_sigcleanarg
+
+lib/readline/complete.c
+ - _rl_complete_sigcleanup: signal cleanup function for completion code;
+ calls _rl_free_match_list on _rl_sigcleanarg if signal == SIGINT
+ - rl_complete_internal: before calling display_matches if what_to_do
+ == `?', set _rl_sigcleanup to _rl_complete_sigcleanup so the match
+ list gets freed on SIGINT; avoids possible memory leak pointed out
+ by Garrett Cooper <yanegomi@gmail.com>
+ - rl_complete_internal: in default switch case, call _rl_free_match_list
+ before returning to avoid memory leak
+
+doc/bashref.texi
+ - start at a set of examples for the =~ regular expression matching
+ operator, touching on keeping the pattern in a shell variable and
+ quoting portions of the pattern to remove their special meaning
+
+ 12/1
+ ----
+lib/glob/gmisc.c
+ - extglob_pattern: new function, returns 1 if pattern passed as an
+ argument looks like an extended globbing pattern
+
+lib/glob/glob.c
+ - skipname: return 0 immediately if extglob_pattern returns non-zero,
+ let the extended globbing code do the right thing with skipping
+ names beginning with a `.'
+ - mbskipname: return 0 immediately if extglob_pattern returns non-zero,
+ let the extended globbing code do the right thing with skipping
+ names beginning with a `.'. Fixes bug reported by Yongzhi Pan
+ <panyongzhi@gmail.com>
+
+ 12/2
+ ----
+lib/glob/smatch.c
+ - patscan, patscan_wc: no longer static so other parts of the glob
+ library can use them, renamed to glob_patscan, glob_patscan_wc
+
+lib/glob/glob.c
+ - extern declarations for glob_patscan, glob_patscan_wc
+ - wchkname: new function, does skipname on wchar_t pattern and dname,
+ old body of mbskipname after converting to wide chars
+ - extglob_skipname: new function, checks all subpatterns in an extglob
+ pattern to determine whether or not a filename should be skipped.
+ Calls skipname for each subpattern. Dname is only skipped if all
+ subpatterns indicate it should be. Better fix for bug reported by
+ Yongzhi Pan <panyongzhi@gmail.com>
+ - wextglob_skipname: wide-char version of extglob_skipname, calls
+ wchkname instead of calling back into mbskipname for each
+ subpattern to avoid problems with char/wchar_t mismatch
+ - skipname: call extglob_skipname if extglob_pattern returns non-zero
+ - mbskipname: call wextglob_skipname if extglob_pattern returns non-zero
+ - mbskipname: short-circuit immediately if no multibyte chars in
+ pattern or filename
+
+execute_cmd.c
+ - execute_cond_node: added parens to patmatch assignment statement to
+ make intent clearer
+
+ 12/3
+ ----
+configure.in,config.h.in
+ - check for imaxdiv, define HAVE_IMAXDIV if present
+
+expr.c
+ - expassign, exp2: use imaxdiv if available. Doesn't help with checks
+ for overflow from 10/25
+
+ 12/6
+ ----
+lib/readline/complete.c
+ - compute_lcd_of_matches: if we're ignoring case in the matches, only
+ use what the user typed as the lcd if it matches the first match
+ (after sorting) up to the length of what was typed (if what the
+ user typed is longer than the shortest of the possible matches, use
+ the shortest common length of the matches instead). If it doesn't
+ match, use the first of the list of matches, as if case were not
+ being ignored. Fixes bug reported by Clark Wang
+ <dearvoid@gmail.com>
+
+ 12/7
+ ----
+builtins/cd.def
+ - cd_builtin: add code to return error in case cd has more than one
+ non-option argument, conditional on CD_COMPLAINS define (which is
+ not defined anywhere)
+
+doc/{bash.1,bashref.texi}
+ - note that additional arguments to cd following the directory name
+ are ignored. Suggested by Vaclav Hanzl <hanzl@noel.feld.cvut.cz>
+
+ 12/10
+ -----
+lib/readline/input.c
+ - rl_read_key: don't need to increment key sequence length here; doing
+ it leads to an off-by-one error
+
+lib/readline/macro.c
+ - rl_end_kbd_macro: after off-by-one error with rl_key_sequence_length
+ fixed, can decrement current_macro_index by rl_key_sequence_length
+ (length of key sequence that closes keyboard macro)
+
+lib/readline/readline.c
+ - _rl_dispatch_subseq: fix extra increment of rl_key_sequence_length
+ when ESC maps to a new keymap and we're converting meta characters
+ to ESC+key
+ - _rl_dispatch_subseq: better increment of rl_key_sequence_length
+ before we dispatch to a function in the ISFUNC case (where the
+ second increment above should have happened)
+ - rl_executing_keyseq: the full key sequence that ended up executing
+ a readline command. Available to the calling application, maintained
+ by _rl_dispatch_subseq, indexed by rl_key_sequence_length
+ - rl_executing_key: the key that was bound to the currently-executing
+ readline command. Same as the `key' argument to the function
+
+lib/readline/readline.h
+ - rl_executing_keyseq: extern declaration
+ - rl_executing_key: extern declaration
+ - rl_key_sequence_length: declaration moved here from rlprivate.h,
+ now part of public interface
+
+lib/readline/rlprivate.h
+ - new extern declaration for _rl_executing_keyseq_size, buffer size
+ for rl_executing_keyseq
+
+lib/readline/doc/rltech.texi
+ - documented new variables: rl_executing_key, rl_executing_keyseq,
+ rl_key_sequence_length
+
+ 12/13
+ -----
+bashline.c
+ - bash_execute_unix_command: replace ad-hoc code that searches
+ cmd_xmap for correct command with call to rl_function_of_keyseq
+ using rl_executing_keyseq; now supports key sequences longer
+ than two characters. Fixes bug reported by Michael Kazior
+ <kazikcz@gmail.com>
+
+ 12/15
+ -----
+make_cmd.c
+ - make_function_def: don't null out source_file before calling
+ make_command so it can be used later on when the function definition
+ is executed
+
+execute_cmd.c
+ - execute_intern_function: second argument is now FUNCTION_DEF *
+ instead of COMMAND *
+ - execute_command_internal: call execute_intern_function with the
+ new second argument (the entire FUNCTION_DEF instead of just the
+ command member)
+ - execute_intern_function: if DEBUGGER is defined, call
+ bind_function_def before calling bind_function, just like
+ make_function_def does (might be able to take out the call in
+ make_function_def depending on what the debugger does with it).
+ Fixes bug reported by <dethrophes@motd005>
+
+expr.c
+ - more minor changes to cases of INTMAX_MIN % -1 and INTMAX_MIN / 1;
+ fix typos and logic errors
+
+ 12/16
+ -----
+bashline.c
+ - find_cmd_start: change flags to remove SD_NOSKIPCMD so it skips over
+ command substitutions and doesn't treat them as command separators
+ - attempt_shell_completion: instead of taking first return from
+ find_cmd_name as command name to use for programmable completion,
+ use loop to skip over assignment statements. Fixes problem reported
+ by Raphael Droz <raphael.droz+floss@gmail.com>
+ - attempt_shell_completion: if we don't find a command name but the
+ command line is non-empty, assume the other words are all assignment
+ statements and flag that point is in a command position so we can
+ do command name completion
+ - attempt_shell_completion: if the word being completed is the first
+ word following a series of assignment statements, and the
+ command line is non-empty, flag that point is in a command position
+ so we can do command name completion
+
+lib/readline/history.c
+ - history_get_time: atol -> strtol
+
+ 12/18
+ -----
+parse.y
+ - parser_in_command_position: external interface to the
+ command_token_position macro for use by other parts of the shell,
+ like the completion mechanism
+
+externs.h
+ - extern declaration for parser_in_command_position
+
+ 12/19
+ -----
+
+builtins/read.def
+ - read_builtin: make sure all calls to bind_read_variable are passed
+ a non-null string. Fixes bug reported by Dan Douglas
+ <ormaaj@gmail.com>
+
+bashline.c
+ - attempt_shell_completion: mark that we're in a command position if
+ we're at the start of the line and the parser is ready to accept
+ a reserved word or command name. Feature most recently suggested
+ by Peng Yu <pengyu.ut@gmail.com>
+
+ 12/21
+ -----
+lib/readline/bind.c
+ - _rl_escchar: return the character that would be backslash-escaped
+ to denote the control character passed as an argument ('\n' -> 'n')
+ - _rl_isescape: return 1 if character passed is one that has a
+ backslash escape
+ - _rl_untranslate_macro_value: new second argument: use_escapes, if
+ non-zero translate to backslash escapes where possible instead of
+ using straight \C-x for control character `x'. Change callers
+ - _rl_untranslate_macro_value: now global
+
+lib/readline/rlprivate.h
+ - _rl_untranslate_macro_value: extern declaration
+
+lib/readline/{macro.c,readline.h}
+ - rl_print_last_kbd_macro: new bindable function, inspired by patch
+ from Mitchel Humpherys
+
+lib/readline/funmap.c
+ - print-last-kbd-macro: new bindable command, bound to
+ rl_print_last_kbd_macro
+
+lib/readline/doc/{rluser.texi,readline.3},doc/bash.1
+ - print-last-kbd-macro: document.
+
+lib/readline/text.c
+ - _rl_insert_next: if we're defining a macro, make sure the key gets
+ added to the macro text (should really audit calls to rl_read_key()
+ and make sure the right thing is happening for all of them)
+
+bashline.[ch]
+ - print_unix_command_map: new function, prints all bound commands in
+ cmd_xmap using rl_macro_dumper in a reusable format
+
+builtins/bind.def
+ - new -X option: print all keysequences bound to Unix commands using
+ print_unix_command_map. Feature suggested by Dennis Williamson
+ (2/2011)
+
+doc/{bash.1,bashref.texi}
+ - document new `bind -X' option
+
+ 12/24
+ -----
+
+doc/{bash.1,bashref.texi}
+ - add a couple of sentences to the description of the case modification
+ operators making it clearer that each character of parameter is
+ tested against the pattern, and that the pattern should only attempt
+ to match a single character. Suggested by Bill Gradwohl
+ <bill@ycc.com>
+
+ 12/28
+ -----
+shell.c
+ - init_noninteractive: instead of calling set_job_control(0) to
+ unconditionally turn off job control, turn on job control if
+ forced_interactive or jobs_m_flag is set
+ - shell_initialize: call initialize_job_control with jobs_m_flag as
+ argument so `bash -m script' enables job control while running the
+ script
+
+jobs.c
+ - initialize_job_control: if the `force' argument is non-zero, turn on
+ job control even if the shell is not currently interactive
+ (interactive == 0)
+
+ 12/29
+ -----
+
+flags.h
+ - new extern declaration for jobs_m_flag
+
+builtins/{cd,set}.def,doc/{bash.1,bashref.texi}
+ - added text clarifying the descriptions of cd -L and -P, suggested by
+ Padraig Brady <p@draigbrady.com>
+ - slight change to the description of `set -P' about resolving symbolic
+ links
+
+lib/readline/doc/rluser.texi
+ - Added an example to the programmable completion section: _comp_cd,
+ a completion function for cd, with additional verbiage. Text
+ includes a reference to the bash_completion project
+
+ 1/1/2012
+ --------
+jobs.c
+ - set_job_status_and_cleanup: note that a job is stopped due to
+ SIGTSTP (any_tstped) if job_control is set; there's no need to
+ test interactive
+
+ 1/5
+ ---
+quit.h
+ - LASTSIG(): new macro, expands to signal number of last terminating
+ signal received (terminating_signal or SIGINT)
+
+trap.c
+ - first_pending_trap: returns lowest signal number with a trap pending
+ - trapped_signal_received: set to the last trapped signal the shell
+ received in trap_handler(); reset to 0 in run_pending_traps
+
+builtins/read.def
+ - read_builtin: changes to posix-mode (posixly_correct != 0) to make
+ `read' interruptible by a trapped signal. After the trap runs,
+ read returns 128+sig and does not assign the partially-read line
+ to the named variable(s). From an austin-group discussion started
+ by David Korn
+
+ 1/11
+ ----
+doc/{bash.1,bashref.texi}
+ - slight changes to the descriptions of the compat32 and compat40 shell
+ options to clarify their meaning
+
+ 1/12
+ ----
+lib/readline/{colors.[ch],parse-colors.[ch]}
+ - new files, part of color infrastructure support
+
+Makefile.in,lib/readline/Makefile.in
+ - arrange to have colors.o and parse-colors.o added to readline
+ library
+
+{configure,config.h}.in
+ - check for stdbool.h, define HAVE_STDBOOL_H if found
+
+ 1/14
+ ----
+lib/readline/bind.c
+ - colored_stats: new bindable variable, enables using colors to
+ indicate file type when listing completions
+
+lib/readline/complete.c
+ - _rl_colored_stats: new variable, controlled by colored-stats bindable
+ variable
+ - colored_stat_start, colored_stat_end: new functions to set and reset
+ the terminal color appropriately depending on the type of the
+ filename to be printed
+ - print_filename: changes to print colors if `colored-stats' variable
+ set. Changes contributed by Raphael Droz
+ <raphael.droz+floss@gmail.com>
+
+lib/readline/readline.c
+ - rl_initialize_everything: add call to _rl_parse_colors to parse
+ color values out of $LS_COLORS. May have to add to rl_initialize
+ to make more dynamic if LS_COLORS changes (which doesn't happen
+ very often, if at all)
+
+lib/readline/rlprivate.h
+ - _rl_colored_stats: new extern declaration
+
+lib/readline/doc/{readline.3,rluser.texi},doc/bash.1
+ - colored-stats: document new bindable readline variable
+
+lib/readline/colors.c
+ - _rl_print_color_indicator: call rl_filename_stat_hook before calling
+ lstat/stat so we can get color indicators for stuff like
+ $HOME/Applications
+
+lib/readline/complete.c
+ - stat_char: call rl_filename_stat_hook before calling lstat/stat
+
+findcmd.[ch],execute_cmd.c
+ - search_for_command: now takes a second `flags' argument; changed
+ header function prototype and callers
+ - search_for_command: if (flags & 1), put the command found in $PATH
+ into the command hash table (previous default behavior)
+
+execute_cmd.c
+ - is_dirname: call search_for_command with flags argument of 0 so it
+ doesn't try to put something in the command hash table
+
+bashline.c
+ - bash_command_name_stat_hook: a hook function for readline's
+ filename_stat_hook that does $PATH searching the same way that
+ execute_cmd.c:execute_disk_command() does it, and rewrites the
+ passed filename if found. Does not put names into command hash
+ table. This allows command name completion to take advantage
+ of `visible-stats' and `colored-stats' settings.
+ - executable_completion: new function, calls the directory completion
+ hook to expand the filename before calling executable_file or
+ executable_or_directory; change command_word_completion_function to
+ call executable_completion. This allows $HOME/bin/[TAB] to do
+ command completion and display alternatives
+
+ 1/17
+ ----
+pcomplete.c
+ - gen_command_matches: now takes a new second argument: the command
+ name as deciphered by the programmable completion code and used
+ to look up the compspec; changed callers (gen_compspec_completions)
+ - gen_shell_function_matches: now takes a new second argument: the
+ command that originally caused the completion function to be
+ invoked; changed callers (gen_compspec_completions))
+ - build_arg_list: now takes a new second argument: the command name
+ corresponding to the current compspec; changed callers
+ (gen_command_matches, gen_shell_function_matches)
+ - build_arg_list: now uses `cmd' argument to create $1 passed to
+ invoked command or shell function
+ - gen_compspec_completions: if we skipped a null command at the
+ beginning of the line (e.g., for completing `>'), add a new word for
+ it at the beginning of the word list and increment nw and cw
+ appropriately. This is all a partial fix for the shortcoming
+ pointed out by Sung Pae <sungpae@gmail.com>
+
+ 1/18
+ ----
+
+{configure,config.h}.in
+ - new check: check for AUDIT_USER_TTY defined in <linux/audit.h>,
+ define HAVE_DECL_AUDIT_USER_TTY if both are found
+
+lib/readline/rlconf.h
+ - ENABLE_TTY_AUDIT_SUPPORT: new define, allows use of the Linux kernel
+ tty auditing system if it's available and enabled
+
+lib/readline/util.c
+ - _rl_audit_tty: new function, send a string to the kernel tty audit
+ system
+
+lib/readline/rlprivate.h
+ - _rl_audit_tty: new extern declaration
+
+lib/readline/readline.c
+ - readline: call _rl_audit_tty with line to be returned before returning
+ it if the Linux tty audit system is available and it's been enabled
+ in rlconf.h Original patch from Miroslav Trmac; recent request
+ from Miroslav Lichvar <mlichvar@redhat.com>
+
+ 1/21
+ ----
+
+lib/readline/readline.c:
+ - _rl_dispatch_subseq: add an inter-character timeout for multi-char
+ key sequences. Suggested by <rogerx.oss@gmail.com>. Still needs
+ work to make a user-settable variable
+
+parse.y
+ - shell_getc: make code that uses the pop_alias dependent on ALIAS
+ define
+
+variables.h
+ - sv_tz: extern define should only depend on HAVE_TZSET
+
+expr.c
+ - expr_streval: if ARRAY_VARS is not defined, set lvalue->ind to -1;
+ move assignment to `ind' inside define
+ - expr_bind_array_element: declaration and uses need to be #ifdef
+ ARRAY_VARS
+
+arrayfunc.h
+ - AV_ALLOWALL, AV_QUOTED, AV_USEIND: define to 0 if ARRAY_VARS not
+ defined; used in subst.c unconditionally
+
+sig.h
+ - make the signal blocking functions not dependent on JOB_CONTROL
+
+sig.c
+ - sigprocmask: make the replacement definition not dependent on
+ JOB_CONTROL
+
+trap.c
+ - use BLOCK_SIGNAL/UNBLOCK_SIGNAL instead of code dependent on
+ HAVE_POSIX_SIGNALS and BSD signals
+
+ 1/24
+ ----
+
+print_cmd.c
+ - print_redirection_list: change the conditions under which
+ r_duplicating_output_word is mapped to r_err_and_out to more or
+ less match those used in redir.c. Fixes bug pointed out by
+ Dan Douglas <ormaaj@gmail.com>
+
+
+ 1/29
+ ----
+lib/readline/signals.c
+ - _rl_block_sigwinch,_rl_release_sigwinch: don't compile in bodies
+ unless SIGWINCH is defined. Fixes bug reported by Pierre Muller
+ <pierre.muller@ics-cnrs.unistra.fr>
+
+doc/{bash.1,bashref.texi}
+ - small modifications to the introduction to the REDIRECTION section
+ to describe how redirections can modify file handles
+ - small modification to the section describing base#n to make it
+ clearer that n can be denoted using non-numerics. From a posting
+ by Linda Walsh <bash@tlinx.org>
+
+ 2/2
+ ---
+builtins/printf.def
+ - printf_builtin: make sure vbuf is intialized and non-null when -v
+ is supplied, since other parts of the code assume that it's not
+ null (e.g., bind_printf_variable()). Fixes bug reported by Jim
+ Avera <james_avera@yahoo.com>
+
+ 2/4
+ ---
+lib/readline/undo.c
+ - _rl_free_undo_list: new function, old body of rl_free_undo_list,
+ frees undo entries in UNDO_LIST * passed as argument
+ - rl_free_undo_list: call _rl_free_undo_list
+
+lib/readline/rlprivate.h
+ - _rl_free_undo_list: new extern declaration
+ - _rl_keyseq_timeout: new extern declaration (see below)
+
+lib/readline/misc.c
+ - rl_clear_history: new function. Clears the history list and frees
+ all associated data similar to history.c:clear_history(), but
+ takes rl_undo_list into account and frees and UNDO_LISTs saved as
+ `data' members of a history list entry
+
+lib/readline/doc/rltech.texi
+ - rl_clear_history: documented
+
+lib/readline/readline.c
+ - _rl_keyseq_timeout: new variable to hold intra-key timeout value
+ from 1/21 fix; specified in milliseconds. Default value is 500
+ - _rl_dispatch_subseq: change to use _rl_keyseq_timeout as intra-key
+ timeout if it's greater than 0; no timeout if <= 0
+ - _rl_dispatch_subseq: don't check for queued keyboard input if we have
+ pushed or pending input, or if we're reading input from a macro
+
+lib/readline/bind.c
+ - keyseq-timeout: new bindable variable, shadows _rl_keyseq_timeout
+ - string_varlist: add keyseq-timeout
+ - sv_seqtimeout: new function to modify value of _rl_keyseq_timeout;
+ clamps negative values at 0 for now
+ - _rl_get_string_variable_value: return value for keyseq-timeout
+
+doc/bash.1,lib/readline/doc/{rluser.texi,readline.3}
+ - keyseq-timeout: documented
+
+lib/readline/isearch.c
+ - _rl_isearch_dispatch: modification to fix from 7/18 to not use
+ cxt->keymap and cxt->okeymap, since by the time this code is
+ executed, they are equal. Use `f' to check for rl_insert or
+ unbound func
+ - _rl_isearch_dispatch: if we're switching keymaps, not in
+ callback mode, and don't have pending or pushed input, use
+ _rl_input_queued to resolve a potentially ambiguous key sequence.
+ Suggested by Roger Zauner <rogerx.oss@gmail.com>
+ - _rl_isearch_dispatch: if we have changed keymaps and resolved to
+ an editing function (not self-insert), make sure we stuff the
+ right characters back onto the input after changing the keymap
+ back so the right editing function is executed after the search
+ is terminated. Rest of fix for bug reported by Roger Zauner
+ <rogerx.oss@gmail.com>
+
+ 2/5
+ ---
+builtins/gen-helpfiles.c
+ - new file: reads struct builtin and writes the long docs to files
+ in the `helpdirs' subdirectory. The filename is given in the
+ previously-unused `handle' member of the struct builtin. Links
+ with `tmpbuiltins.o', which is created by Makefile to have the
+ right long documentation. When not cross-compiling, gets the
+ right #defines based on configuration options from config.h instead
+ of trying to parse conditional parts of def files. Fixes
+ shortcoming pointed out by Andreas Schwab <schwab@linux-m68k.org>
+
+builtins/Makefile.in
+ - tmpbuiltins.c: new generated file, created to enable creation of
+ separate helpfiles based on correct #defines instead of trying to
+ parse conditional parts of def files
+ - gen-helpfiles: new program to generate helpfiles, links with
+ tmpbuiltins.o
+ - HELPFILES_TARGET: new target, substituted by configure to `helpdoc'
+ if separate helpfiles requested
+ - targets: new target, libbuiltins.a and $(HELPFILES_TARGET)
+ - CREATED_OBJECTS: new variable, holds created object files for
+ make clean; changed make clean to remove created objects
+ - helpdoc: changed to call gen-helpfiles instead of mkbuiltins
+
+Makefile.in
+ - when building libbuiltins.a, recursively call make with `targets'
+ argument to make sure separate helpfiles get built
+
+configure.in
+ - substitute `helpdoc' as value of HELPFILES_TARGET if
+ --enable-separate-helpfiles supplied as configure argument
+
+builtins/mkbuiltins.c
+ - `-nofunctions': new argument, causes mkbuiltins to not write value
+ for function implementing a particular builtin to struct builtin
+ and to write document file name to `handle' member of struct builtin
+ - no longer writes separate helpfiles; that is left to gen-helpfiles
+
+ 2/8
+ ---
+subst.c
+ - make sure last_command_exit_value is set to a non-zero value before
+ any calls to report_error, since `-e' set will short-circuit
+ report_error. Fixes bug reported by Ewan Mellor
+ <Ewan.Mellor@eu.citrix.com>
+
+variables.c
+ - make_local_array_variable: added second argument; if non-zero,
+ function will return an existing local associative array variable
+ instead of insisting on an indexed array
+
+variable.h,subst.c
+ - make_local_array_variable: changed prototype and caller
+
+builtins/declare.def
+ - declare_internal: add second arg to call to make_local_array_variable;
+ making_array_special, which indicates we're processing an
+ assignment like declare a[b]=c. Fixes seg fault resulting from
+ a being an already-declared local associative array variable in a
+ function. Ubuntu bash bug 928900.
+
+ 2/14
+ ----
+
+execute_cmd.c
+ - execute_command_internal: if redirections into or out of a loop fail,
+ don't try to free ofifo_list unless saved_fifo is non-zero. It's
+ only valid if saved_fifo is set
+
+ 2/15
+ ----
+{arrayfunc,braces,variables}.c
+ - last_command_exit_value: make sure it's set before any calls to
+ report_error, since -e will cause that to exit the shell
+
+builtins/common.c
+ - get_job_by_name: call internal_error instead of report_error so this
+ doesn't exit the shell
+
+ 2/18
+ ----
+builtins/evalstring.c
+ - parse_and_execute: make sure the file descriptor to be redirected to
+ is 1 before calling cat_file. One fix for bug reported by Dan Douglas
+ <ormaaj@gmail.com>
+
+parse.y
+ - read_token_word: don't return NUMBER if a string of all digits
+ resolves to a number that overflows the bounds of an intmax_t.
+ Other fix for bug reported by Dan Douglas <ormaaj@gmail.com>
+
+ 2/19
+ ----
+lib/sh/strtrans.c
+ - ansicstr: use 0x7f as the boundary for characters that translate
+ directly from ASCII to unicode (\u and \U escapes) instead of
+ UCHAR_MAX, since everything >= 0x80 requires more than one byte.
+ Bug and fix from John Kearney <dethrophes@web.de>
+
+builtins/printf.def
+ - tescape: ditto for printf \u and \U escape sequences
+
+ 2/20
+ ----
+lib/sh/unicode.c
+ - u32toutf8: fix to handle encodings up to six bytes long correctly
+ (though technically UTF-8 only has characters up to 4 bytes long).
+ Report and fix from John Kearney <dethrophes@web.de>
+ - u32toutf8: first argument is now an unsigned 32-bit quantity,
+ changed callers (u32cconv) to pass c instead of wc
+ - u32reset: new function, resets local static state to uninitialized
+ (locale information, currently)
+
+locale.c
+ - call u32reset whenever LC_CTYPE/LC_ALL/LANG is changed to reset the
+ cached locale information used by u32cconv. From a report from
+ John Kearney <dethrophes@web.de>
+
+ 2/21
+ ----
+doc/{bash,builtins}.1
+ - minor changes from Bjarni Ingi Gislason <bjarniig@rhi.hi.is>
+
+lib/sh/unicode.c
+ - u32cconv: only assume you can directly call wctomb on the passed
+ value if __STDC_ISO_10646__ is defined and the value is <=
+ 0x7fffffff
+ - stub_charset: return locale as default instead of "ASCII", let
+ rest of code decide what to do with it
+
+lib/readline/parens.c
+ - _rl_enable_paren_matching: make paren matching work in vi insert
+ mode. Bug report from <derflob@derflob.de>
+
+ 2/22
+ ----
+lib/sh/shquote.c
+ - sh_backslash_quote: quote tilde in places where it would be
+ expanded. From a report from John Kearney <dethrophes@web.de>
+
+ 2/23
+ ----
+execute_cmd.c
+ - execute_pipeline: wrap the discard_unwind_frame call in #ifdef
+ JOB_CONTROL, since the frame is only created if JOB_CONTROL is
+ defined. Bug and fix from Doug Kehn <rdkehn@yahoo.com>
+
+ 2/25
+ ----
+error.c
+ - report_error: make sure last_command_exit_value is non-zero before
+ we call exit_shell, since the exit trap may reference it. Call
+ exit_shell with last_command_exit_value to allow exit statuses
+ other than 1
+
+unicode.c
+ - stub_charset: use local static buffer to hold charset, don't change
+ value returned by get_locale_var. Based on idea and code from
+ John Kearney <dethrophes@web.de>
+ - u32toutf16: function to convert unsigned 32-bit value (unicode) to
+ UTF-16. From John Kearney <dethrophes@web.de>
+ - u32cconv: call u32toutf16 if __STDC_ISO_10646__ defined and wchar_t
+ is two bytes, send result to wcstombs, return if not encoding error.
+ From John Kearney <dethrophes@web.de>
+ - u32cconv: return UTF-8 conversion if iconv conversion to local
+ charset is unsupported
+
+ 3/2
+ ---
+lib/readline/complete.c
+ - print_filename: if there is no directory hook, but there is a stat
+ hook, and we want to append a slash to directories, call the stat
+ hook before calling path_isdir on the expanded directory name.
+ Report and pointer to fix from Steve Rago <sar@nec-labs.com>
+
+ 3/3
+ ---
+builtins/evalstring.c
+ - parse_and_execute: fix to change of 2/18: make sure the file
+ descriptor being redirected to is 0 before calling cat_file when
+ we see something like $(< file). Real fix for bug reported by
+ Dan Douglas <ormaaj@gmail.com>
+
+subst.c
+ - parameter_brace_patsub: run the replacement string through quote
+ removal even if the expansion is within double quotes, because
+ the parser and string extract functions treat the quotes and
+ backslashes as special. If they're treated as special, quote
+ removal should remove them (this is the Posix position and
+ compatible with ksh93). THIS IS NOT BACKWARDS COMPATIBLE.
+
+ 3/4
+ ---
+lib/readline/complete.c
+ - rl_menu_complete: fix to make show-all-if-ambiguous and
+ menu-complete-display-prefix work together if both are set. Fix
+ from Sami Pietila <sami.pietila@gmail.com>
+
+ 3/5
+ ---
+bashline.c
+ - dircomplete_expand_relpath: new variable, if non-zero, means that
+ `shopt -s direxpand' should expand relative pathnames. Zero by
+ default, not user-settable yet
+ - bash_directory_completion_hook: if we have a relative pathname that
+ isn't changed by canonicalization or spell checking after being
+ appended to $PWD, then don't change what the user typed. Controlled
+ by dircomplete_expand_relpath
+
+ 3/7
+ ---
+m4/timespec.m4
+ - new macros, cribbed from gnulib and coreutils: find out whether we
+ have `struct timespec' and what file includes it
+
+m4/stat-time.m4
+ - new macros, cribbed from gnulib and coreutils: find out whether the
+ mtime/atime/ctime/etctime fields of struct stat are of type
+ struct timespec, and what the name is
+
+include/stat-time.h
+ - new file, cribbed from gnulib, with additions from coreutils: include
+ the right file to get the struct timespec define, or provide our own
+ replacement. Provides a bunch of inline functions to turn the
+ appropriate members of struct stat into `struct timespec' values,
+ zeroing out the tv_nsec field if necessary
+
+test.c
+ - include "stat-time.h" for the nanosecond timestamp resolution stuff
+ - stat_mtime: new function, returns struct stat and the mod time
+ normalized into a `struct timespec' for the filename passed as the
+ first argument
+ - filecomp: call stat_mtime instead of sh_stat for each filename
+ argument to get the mtime as a struct timespec
+ - filecomp: call timespec_cmp instead of using a straight arithmetic
+ comparison for the -nt and -ot operators, using timespec returned by
+ stat_mtime. Added functionality requested by by Werner Fink
+ <werner@suse.de> for systems that can support it
+
+ 3/10
+ ----
+include/posixdir.h
+ - REAL_DIR_ENTRY: remove dependency on _POSIX_SOURCE, only use feature
+ test macros to decide whether dirent.d_ino is present and usable;
+ define D_INO_AVAILABLE. Report and fix from Fabrizion Gennari
+ <fabrizio.ge@tiscali.it>
+ - D_FILENO_AVAILABLE: define if we can use dirent.d_fileno
+
+lib/sh/getcwd.c
+ - use D_FILENO_AVAILABLE to decide whether or not to compile in
+ _path_checkino and whether or not to call it. Report and initial
+ fix from Fabrizion Gennari <fabrizio.ge@tiscali.it>
+
+lib/readline/signals.c
+ - make sure all occurrences of SIGWINCH are protected by #ifdef
+
+sig.c
+ - make sure all occurrences of SIGCHLD are protected by #ifdef
+
+nojobs.c
+ - make sure SA_RESTART is defined to 0 if the OS doesn't define it
+
+version.c
+ - show_shell_version: don't use string literals in printf, use %s.
+ Has added benefit of removing newline from string to be translated
+
+trap.c
+ - queue_sigchld_trap: new function, increments the number of pending
+ SIGCHLD signals by the argument, which is by convention the number
+ of children reaped in a call to waitchld()
+
+trap.h
+ - queue_sigchld_trap: new extern declaration
+
+jobs.c
+ - waitchld: if called from the SIGCHLD signal handler (sigchld > 0),
+ then call queue_sigchld_trap to avoid running the trap in a signal
+ handler context. Report and original fix from Siddhesh Poyarekar
+ <siddhesh@redhat.com>
+
+lib/sh/unicode.c
+ - u32tocesc: take an unsigned 32-bit quantity and encode it using
+ ISO C99 string notation (\u/\U)
+ - u32cconv: call u32tocesc as a fallback instead of u32cchar
+ - u32cconv: call u32tocesc if iconv cannot convert the character.
+ Maybe do the same thing if iconv_open fails
+ - u32reset: call iconv_close on localconv if u32init == 1
+
+ 3/11
+ ----
+config-top.h
+ - CHECKWINSIZE_DEFAULT: new define, set to initial value of
+ check_window_size (shopt checkwinsize): 0 for off, 1 for on.
+ Default is 0
+
+{jobs,nojobs}.c
+ - check_window_size: default initial value to CHECKWINSIZE_DEFAULT
+
+ 3/13
+ ----
+doc/bashref.texi
+ - change text referring to the copying restrictions to that
+ recommended by the FSF (no Front-Cover Texts and no Back-Cover
+ Texts)
+
+lib/readline/doc/{history,rlman,rluserman}.texi
+ - change text referring to the copying restrictions to that
+ recommended by the FSF (no Front-Cover Texts and no Back-Cover
+ Texts)
+
+ 3/15
+ ----
+array.c
+ - LASTREF_START: new macro to set the starting position for an array
+ traversal to `lastref' if that's valid, and to the start of the array
+ if not. Used in array_reference, array_insert, array_remove
+ - array_remove: try to be a little smarter with lastref instead of
+ unconditionally invalidating it
+
+ 3/16
+ ----
+array.c
+ - array_insert: fix memory leak by deleting element to be added in the
+ case of an error
+
+ 3/18
+ ----
+lib/sh/mbschr.c
+ - mbschr: don't call mbrlen unless is_basic is false; devolves to a
+ straight character-by-character run through the string
+
+ 3/19
+ ----
+stringlib.c
+ - substring: use memcpy instead of strncpy, since we know the length
+ and are going to add our own NUL terminator
+
+ 3/20
+ ----
+subst.c
+ - parameter_brace_expand_rhs: if expand_string_for_rhs returns a quoted
+ null string (a list with one element for which
+ QUOTED_NULL(list->word->word) returns true), return the quoted null
+ and set the flags in the returned word to indicate it. Fixes bug
+ reported by Mark Edgar <medgar123@gmail.com>
+
+lib/sh/tmpfile.c
+ - use random(3) instead of get_random_number to avoid perturbing the
+ random sequence you get using $RANDOM. Bug report and fix from
+ Jurij Mihelic <jurij.mihelic@fri.uni-lj.si>
+
+ 3/21
+ ----
+config-top.h
+ - OPTIMIZE_SEQUENTIAL_ARRAY_ASSIGNMENT: define to 1 to optimize
+ sequential indexed array assignment patterns. Defined to 1 by
+ default
+
+array.c
+ - array_insert: if OPTIMIZE_SEQUENTIAL_ARRAY_ASSIGNMENT is defined,
+ start the search at lastref (see change from 3/15)
+
+ 3/27
+ ----
+print_cmd.c
+ - debug_print_word_list: new debugging function, prints a word list
+ preceded by an optional string and using a caller-specified
+ separator
+
+ 4/1
+ ---
+command.h
+ - W_ASSNGLOBAL: new flag, set to indicate declare -g
+
+execute_cmd.c
+ - fix_assignment_words: note that we have a -g argument to an assignment
+ builtin and set the W_ASSNGLOBAL flag in the variable word
+
+subst.c
+ - dump_word_flags: print out W_ASSNGLOBAL if present
+ - do_assignment_internal: only set ASS_MKLOCAL if W_ASSIGNARG is set
+ and W_ASSNGLOBAL is not. Don't want to create a local variable even
+ if variable_context is non-zero if ASSNGLOBAL is set. Fixes bug
+ reported by Bill Gradwohl <bill@ycc.com>
+
+ 4/7
+ ---
+lib/readline/readline.c
+ - _rl_dispatch_subseq: make the `keyseq-timeout' variable apply to
+ ESC processing when in vi mode. After hitting ESC, readline will
+ wait up to _rl_keyseq_timeout*1000 microseconds (if set) for
+ additional input before dispatching on the ESC and switching to
+ command/movement mode. Completes timeout work suggested by
+ <rogerx.oss@gmail.com>; this prompted by report from Barry Downes
+ <barry.downes@gmail.com>
+
+lib/sh/shmbchar.c
+ - sh_mbsnlen: new function, returns the number of (possibly multibyte)
+ characters in a passed string with a passed length, examining at most
+ maxlen (third argument) bytes
+
+externs.h
+ - sh_mbsnlen: extern declaration for new function
+
+shell.c
+ - exit_shell: call maybe_save_shell_history if remember_on_history is
+ set, not just in interactive shells. That means the history is
+ saved if history is enabled, regardless of whether or not the shell
+ is interactive
+
+doc/{bash.1,bashref.texi}
+ - TMOUT: fix description to make it explicit that TMOUT is the timeout
+ period for a complete line of input, not just any input. Fixes
+ problem reported in Ubuntu bug 957303:
+ https://bugs.launchpad.net/ubuntu/+source/bash/+bug/957303
+ - HISTFILE: document change to write history list to history file in
+ any shell with history enabled, not just interactive shells. This
+ seems to be more logical behavior. Suggested by Greg Wooledge
+ <wooledg@eeg.ccf.org>
+
+ 4/12
+ ----
+lib/readline/colors.h
+ - only include stdbool.h if HAVE_STDBOOL_H is defined
+ - if HAVE_STDBOOL_H is not defined, provide enough definition for the
+ library to use `bool', `true', and `false'
+
+lib/readline/parse-colors.[ch]
+ - don't try to include <stdbool.h> at all; rely on colors.h to do it
+
+lib/sh/snprintf.c
+ - vsnprintf_internal: only treat '0' as a flag to indicate zero padding
+ if `.' hasn't been encountered ((flags&PF_DOT) == 0); otherwise treat
+ it as the first digit of a precision specifier. Fixes bug reported
+ by Petr Sumbera <petr.sumbera@sun.com>
+
+ 4/15
+ ----
+lib/sh/snprintf.c
+ - vsnprintf_internal: if the '0' and '-' flags both occur, the '0'
+ flag is ignored -- Posix. Start of a series of fixes based on
+ tests and patches from Petr Sumbera <petr.sumbera@sun.com>
+ - PUT_PLUS: make sure PF_PLUS flag is specified before putting the `+'
+ - vsnprintf_internal: when '+' is read as a flag, don't set right-
+ justify flag if the LADJUST (`-') flag has already been supplied
+ - floating: make sure to output space padding before the `+', zero
+ padding after
+ - exponent: make sure to output space padding before the `+', zero
+ padding after
+ - exponent: only subtract one from the width for the decimal point
+ if we're really going to print one
+ - floating: use presence of PF_PLUS flag to decide whether to account
+ for the `+' in the padded field width. Ditto for exponent()
+
+ 4/16
+ ----
+lib/sh/snprintf.c
+ - vsnprint_internal: only reduce precision by 1 when processing the `g'
+ format if it's > 0. A precision of 0 should stay 0; otherwise it
+ gets set to -1 (NOT_FOUND) and converted to the default
+ - number, lnumber: if an explicit precision is supplied, turn off the
+ zero-padding flag and set the pad character back to space
+ - number, lnumber: only account for a `+' when performing the field
+ width calculation if the coversion is base 10; we don't add a `+'
+ for other bases
+
+ 4/18
+ ----
+tests/printf3.sub
+ - try using "perl -e 'print time'" to get the current time in seconds
+ since the epoch if "date +%s" is not available (solaris 8-10)
+
+ 4/19
+ ----
+tests/run-printf
+ - use cat -v instead of relying on diff -a being available to convert
+ control characters to ascii and avoid the dreaded "Binary files
+ /tmp/xx and printf.right differ"
+
+ 4/20
+ ----
+lib/sh/strftime.c
+ - incoporated new version from Aharon Robbins <arnold@skeeve.com>
+
+ 4/22
+ ----
+doc/{bash.1,bashref.texi}
+ - slight change to the description of /dev/tcp and /dev/udp
+
+subst.c
+ - match_wpattern: logic fix to the calculation of `simple' (was |=,
+ needs to be &=). Bug report from Mike Frysinger <vapier@gentoo.org>,
+ fix from Andreas Schwab <schwab@linux-m68k.org>
+
+bashline.c
+ - bash_filename_stat_hook: add code from bash_directory_completion_hook
+ that performs pathname canonicalization in the same way that cd and
+ other builtins will do
+
+ 4/25
+ ----
+execute_cmd.c
+ - execute_pipeline: change the call to move_to_high_fd to make it use
+ getdtablesize() and to not stomp on existing open file descriptors,
+ like the fd the shell is using to read a script. Bug report from
+ Greg Wooledge <wooledg@eeg.ccf.org>
+
+ 5/6
+ ---
+subst.c
+ - expand_word_internal: case '$': after calling param_expand and
+ setting had_quoted_null, set TEMP to null. The code that builds the
+ returned string at the end of the function will take care of making
+ and returning a quoted null string if there's nothing else in
+ ISTRING. If there is, the quoted null should just go away. Part of
+ fix for bug reported by Ruediger Kuhlmann <RKuhlmann@orga-systems.com>
+ - expand_word_internal: when processing ISTRING to build return value,
+ only set W_HASQUOTEDNULL in the returned word flags if the word is
+ a quoted null string AND had_quoted_null is set. Rest of fix
+
+ 5/9
+ ---
+variables.c
+ - bind_variable_internal: if we get an array variable here (implicit
+ assignment to index 0), call make_array_variable_value, which
+ dummies up a fake SHELL_VAR * from array[0]. This matters when
+ we're appending and have to use the current value
+ - bind_variable_internal: after computing the new value, treat assoc
+ variables with higher precedence than simple array variables; it
+ might be that a variable has both attributes set
+
+arrayfunc.c
+ - bind_array_var_internal: break code out that handles creating the
+ new value to be assigned to an array variable index into a new
+ function, make_array_variable_value. This handles creating a
+ dummy SHELL_VAR * for implicit array[0] assignment. Fixes bug
+ reported by Dan Douglas <ormaaj@gmail.com>
+
+arrayfunc.h
+ - make_array_variable_value: new extern declaration
+
+ 5/19
+ ----
+variables.c
+ - bind_int_variable: if an assignment statement like x=y comes in
+ from the expression evaluator, and x is an array, handle it like
+ x[0]=y. Fixes bug reported by Dan Douglas <ormaaj@gmail.com>
+
+ 5/24
+ ----
+
+braces.c
+ - mkseq: handle possible overflow and break the sequence generating
+ loop if it occurs. Fixes OpenSUSE bug 763591:
+ https://bugzilla.novell.com/show_bug.cgi?id=763591
+
+ 5/25
+ ----
+Makefile.in
+ - LDFLAGS_FOR_BUILD: add to compilation recipes for build tools
+ buildversion, mksignames, mksyntax
+ - LDFLAGS_FOR_BUILD: add to compilation recipes for test tools
+ recho, zecho, printenv, xcase
+
+builtins/Makefile.in
+ - LDFLAGS_FOR_BUILD: add to compilation recipes for build tools
+ gen-helpfiles, psize.aux
+
+variables.c
+ - bind_int_variable: if LHS is a simple variable name without an array
+ reference, but resolves to an array variable, call
+ bind_array_variable with index 0 to make x=1 equivalent to x[0]=1.
+ Fixes bug reported by Dan Douglas <ormaaj@gmail.com>
+
+ 5/27
+ ----
+subst.c
+ - expand_word_internal: make sure has_dollar_at doesn't get reset before
+ recursive calls to param_expand or expand_word_internal, since it has
+ to save state of what came before. Use temp variable and make sure
+ has_dollar_at is incremented if recursive call processes "$@".
+ Fixes bug reported by gregrwm <backuppc-users@whitleymott.net> and
+ supplemented by Dan Douglas <ormaaj@gmail.com>
+
+doc/{bash.1,bashref.texi}
+ - changes to the description of substring expansion inspired by
+ suggestions from Bill Gradwohl <bill@ycc.com>
+
+doc/bashref.texi
+ - added substring expansion examples inspired by suggestions from
+ Bill Gradwohl <bill@ycc.com>
+
+variables.c
+ - find_shell_variable: search for a variable in the list of shell
+ contexts, ignore the temporary environment
+ - find_variable_tempenv: search for a variable in the list of shell
+ contexts, force search of the temporary environment
+ - find_variable_notempenv: search for a variable in the list of shell
+ contexts, don't force search of the temporary environment
+
+variables.h
+ - find_shell_variable: extern declaration
+ - find_variable_tempenv: extern declaration
+ - find_variable_notempenv: extern declaration
+
+arrayfunc.c
+ - bind_array_variable: call find_shell_variable instead of calling
+ var_lookup directly
+
+findcmd.c
+ - search_for_command: call find_variable_tempenv instead of
+ find_variable_internal directly
+ - _find_user_command_internal: call find_variable_tempenv instead of
+ find_variable_internal directly
+
+builtins/setattr.def
+ - set_var_attribute: call find_variable_notempenv instead of
+ find_variable_internal directly
+ - show_name_attributes: call find_variable_tempenv instead of
+ find_variable_internal directly
+
+ 6/1
+ ---
+sig.c
+ - termsig_handler: don't try to save the shell history on a terminating
+ signal any more, since it just causes too many problems on Linux
+ systems using glibc and glibc malloc
+
+lib/readline/vi_mode.c
+ - rl_vi_change_to: change to correctly redo `cc', since `c' is not a vi
+ motion character. From Red Hat bug 813289
+ - rl_vi_delete_to: change to correctly redo `dd', since `d' is not a vi
+ motion character
+ - rl_vi_yank_to: change to correctly redo `yy', since `y' is not a vi
+ motion character
+
+ 6/4
+ ---
+lib/sh/mktime.c
+ - current versions of VMS do not need to include <stddef.h>. Fix from
+ John E. Malmberg <wb8tyw@qsl.net>
+
+ 6/5
+ ---
+lib/sh/eaccess.c
+ - sh_stat: instead of using a static buffer to do the DEV_FD_PREFIX
+ translation, use a dynamically-allocated buffer that we keep
+ resizing. Fixes potential security hole reported by David Leverton
+ <levertond@googlemail.com>
+
+ 6/5
+ ---
+braces.c
+ - expand_seqterm: check errno == ERANGE after calling strtoimax for
+ rhs and incr. Part of a set of fixes from Scott McMillan
+ <scotty.mcmillan@gmail.com>
+ - expand_seqterm: incr now of type `intmax_t', which changes
+ arguments to mkseq
+ - mkseq: a better fix for detecting overflow and underflow since it's
+ undefined in C and compilers `optimize' out overflow checks. Uses
+ ADDOVERFLOW and SUBOVERFLOW macros
+ - mkseq: use sh_imaxabs (new macro) instead of abs() for intmax_t
+ variables
+ - mkseq: don't allow incr to be converted to -INTMAX_MIN
+ - mkseq: make sure that strvec_create isn't called with a size argument
+ greater than INT_MAX, since it only takes an int
+
+ 6/6
+ ---
+braces.c
+ - mkseq: try and be smarter about not overallocating elements in
+ the return array if the increment is not 1 or -1
+
+ 6/7
+ ---
+parse.y
+ - history_delimiting_chars: if the parser says we're in the middle of
+ a compound assignment (PST_COMPASSIGN), just return a space to avoid
+ adding a stray semicolon to the history entry. Fixes bug reported
+ by "Davide Brini" <dave_br@gmx.com>
+
+ 6/8
+ ---
+bashline.c
+ - bash_directory_completion_hook: don't attempt spelling correction
+ on the directory name unless the direxpand option is set and we are
+ going to replace the directory name with the corrected one in the
+ readline line. Suggested by Linda Walsh <bash@tlinx.org>
+
+lib/sh/shquote.c
+ - sh_backslash_quote: now takes a third argument: flags. If non-zero,
+ tildes are not backslash-escaped. Have to handle both printf %q,
+ where they should be escaped, and filename completion, where they
+ should not when used as usernames
+
+externs.h
+ - sh_backslash_quote: declaration now takes a third argument
+
+builtins/printf.def
+ - printf_builtin: call sh_backslash_quote with 1 as third argument
+ so tildes get escaped
+
+{bashline,bracecomp}.c
+ - call sh_backslash_quote with 0 as third argument so tildes are not
+ escaped in completed words
+
+doc/bash.1
+ - add `coproc' to the list of reserved words. From a report by
+ Jens Schweikhardt <schweikh@schweikhardt.net>
+
+ 6/10
+ ----
+execute_cmd.c
+ - line_number_for_err_trap: now global, so parse_and_execute can save
+ and restore it with unwind-protect
+
+builtins/evalstring.c
+ - parse_prologue: save and restore line_number_for_err_trap along
+ with line_number
+ - restore_lastcom: new function, unwind-protect to restore
+ the_printed_command_except_trap
+ - parse_prologue: use restore_lastcom to save and restore the value
+ of the_printed_command_except_trap around calls to parse_and_execute
+ (eval/source/.)
+
+ 6/15
+ ----
+lib/readline/complete.c
+ - complete_fncmp: change filename comparison code to understand
+ multibyte characters, even when doing case-sensitive or case-mapping
+ comparisons. Fixes problem reported by Nikolay Shirokovskiy
+ <nshyrokovskiy@gmail.com>
+
+ 6/20
+ ----
+builtins/mapfile.def
+ - mapfile: move the line count increment and check for having read
+ the specified number of lines to the end of the loop to avoid
+ reading an additional line with zgetline. Fixes bug reported by
+ Dan Douglas <ormaaj@gmail.com>
+
+ 6/21
+ ----
+
+execute_cmd.c
+ - execute_pipeline: make sure `lastpipe_flag' is initialized to 0 on
+ all systems, since it's tested later in the function. Fixes bug
+ reported by John E. Malmberg <wb8tyw@qsl.net>
+
+ 6/22
+ ----
+mailcheck.c
+ - file_mod_date_changed: return 0 right away if mailstat() does not
+ return success. Fixes bug with using uninitialized values reported
+ by szymon.kalasz@uj.edu.pl
+
+builtins/set.def
+ - the `monitor' option is not available when the shell is compiled
+ without job control, since the underlying `m' flag is not available
+
+nojobs.c
+ - job_control: now declared as int variable, initialized to 0, never
+ modified
+
+jobs.h
+ - job_control: extern declaration no longer dependent on JOB_CONTROL
+
+execute_cmd.c
+ - execute_pipeline: made necessary changes so `lastpipe' shell option
+ is now available in all shells, even those compiled without
+ JOB_CONTROL defined
+
+ 6/23
+ ----
+lib/glob/glob.c
+ - glob_filename: check for interrupts before returning if glob_vector
+ returns NULL or an error. Bug reported by Serge van den Boom
+ <svdb@stack.nl>, fix from Andreas Schwab <schwab@linux-m68k.org>
+ - call run_pending_traps after each call to QUIT or test of
+ interrupt_state, like we do in mainline shell code
+ - glob_vector: don't call QUIT; in `if (lose)' code block; just free
+ memory, return NULL, and let callers deal with interrupt_state or
+ other signals and traps
+
+ 6/25
+ ----
+lib/readline/input.c
+ - rl_read_key: restructure the loop that calls the event hook a little,
+ so that the hook is called only after rl_gather_tyi returns no input,
+ and any pending input is returned first. This results in better
+ efficiency for processing pending input without calling the hook
+ on every input character as bash-4.1 did. From a report from
+ Max Horn <max@quendi.de>
+
+ 6/26
+ ----
+trap.c
+ - signal_is_pending: return TRUE if SIG argument has been received and
+ a trap is waiting to execute
+
+trap.h
+ - signal_is_pending: extern declaration
+
+lib/glob/glob.c
+ - glob_vector: check for pending SIGINT trap each time through the loop,
+ just like we check for interrupt_state or terminating_signal, and
+ set `lose = 1' so we clean up after ourselves and interrupt the
+ operation before running the trap. This may require a change later,
+ maybe call run_pending_traps and do that if run_pending_traps returns?
+
+variables.c
+ - sv_histtimefmt: set history_comment_character to default (`#') if
+ it's 0 when we're turning on history timestamps. The history code
+ uses the history comment character to prefix timestamps, and
+ leaving it at 0 effectively removes them from the history. From a
+ report to help-bash by Dennis Williamson <dennistwilliamson@gmail.com>
+
+ 6/27
+ ----
+lib/readline/signals.c
+ - rl_maybe_restore_sighandler: new function, sets handler for SIG to
+ HANDLER->sa_handler only if it's not SIG_IGN. Needs to be called
+ on same signals set using rl_maybe_set_sighandler, which does not
+ override an existing SIG_IGN handler (SIGALRM is ok since it does
+ the check inline; doesn't mess with SIGWINCH)
+
+ 6/30
+ ----
+variables.h
+ - additional defines for the new `nameref' variable attribute
+ (att_nameref): nameref_p, nameref_cell, var_setref
+
+variables.c
+ - find_variable_nameref: resolve SHELL_VAR V through chain of namerefs
+ - find_variable_last_nameref: resolve variable NAME until last in a
+ chain of possibly more than one nameref starting at shell_variables
+ - find_global_variable_last_nameref: resolve variable NAME until last
+ in a chain of possibly more than one nameref starting at
+ global_variables
+ - find_nameref_at_context: resolve SHELL_VAR V through chain of namerefs
+ in a specific variable context (usually a local variable hash table)
+ - find_variable_nameref_context: resolve SHELL_VAR V through chain of
+ namerefs following a chain of varible contexts
+ - find_variable_last_nameref_context: resolve SHELL_VAR V as in
+ find_variable_last_context, but return the final nameref instead of
+ what the final nameref resolves to
+ - find_variable_tempenv, find_variable_notempenv, find_global_variable,
+ find_shell_variable, find_variable: modified to follow namerefs
+ - find_global_variable_noref: look up a global variable without following
+ any namerefs
+ - find_variable_noref: look up a shell variable without following any
+ namerefs
+ - bind_variable_internal: modify to follow a chain of namerefs in the
+ global variables table; change to handle assignments to a nameref by
+ following nameref chain
+ - bind_variable: modify to follow chain of namerefs when binding to a
+ local variable
+ - unbind_variable: changes to unset nameref variables (unsets both
+ nameref and variable it resolves to)
+
+subst.c
+ - parameter_brace_expand_word: change to handle expanding nameref whose
+ value is x[n]
+ - parameter_brace_expand_indir: change to expand in ksh93-compatible
+ way if variable to be indirected is nameref and a simple (non-array)
+ expansion
+ - param_expand: change to expand $foo where foo is a nameref whose value
+ is x[n]
+
+execute_cmd.c
+ - execute_for_command: changes to implement ksh93 semantics when index
+ variable is a nameref
+
+builtins/setattr.def
+ - show_var_attributes: change to add `n' to flags list if att_nameref
+ is set
+
+builtins/set.def
+ - unset_builtin: changes to error messages to follow nameref variables
+
+builtins/declare.def
+ - document new -n option
+ - declare_internal: new `-n' and `+n' options
+ - declare_internal: handle declare -n var[=value] and
+ declare +n var[=value] for existing and non-existant variables.
+ Enforce restriction that nameref variables cannot be arrays.
+ Implement semi-peculiar ksh93 semantics for typeset +n ref=value
+
+ 7/5
+ ---
+variables.c
+ - unbind_variable: unset whatever a nameref resolves to, leaving the
+ nameref variable itself alone
+ - unbind_nameref: new function, unsets a nameref variable, not the
+ variable it references
+
+variables.h
+ - unbind_nameref: extern declaration
+
+builtins/set.def
+ - unset_builtin: modify to add -n option, which calls unbind_nameref
+ leaving unbind_variable for the usual case. This required slight
+ changes and additions to the test suite
+
+doc/{bash.1,bashref.texi}
+ - document namerefs and typeset/declare/local/unset -n
+
+ 7/13
+ ----
+lib/sh/casemod.c
+ - include shmbchar.h for is_basic and supporting pieces
+ - sh_casemod: use _to_wupper and _to_wlower to convert wide character
+ case instead of TOUPPER and TOLOWER. Fixes bug reported by
+ Dennis Williamson <dennistwilliamson@gmail.com>, fix from
+ Andreas Schwab <schwab@linux-m68k.org>
+ - cval: short-circuit and return ascii value if is_basic tests true
+ - sh_casemod: short-circuit and use non-multibyte case modification
+ and toggling code if is_basic tests true
+
+lib/readline/signals.c
+ - _rl_{block,release}_sigint: remove the code that actually blocks and
+ releases the signals, since we defer signal handling until calls to
+ RL_CHECK_SIGNALS()
+
+lib/readline/{callback,readline,util}.c
+ - if HAVE_POSIX_SIGSETJMP is defined, use sigsetjmp/siglongjmp without
+ saving and restoring the signal mask instead of setjmp/longjmp
+
+lib/readline/rltty.c
+ - prepare_terminal_settings: don't mess with IXOFF setting if
+ USE_XON_XOFF defined
+
+doc/{bash.1,bashref.texi}
+ - add some text to the description of set -e clarifying its effect
+ on shell functions and shell function execution. Suggested by
+ Rainer Blome <rainer.blome@gmx.de>
+
+bashline.c
+ - edit_and_execute_command: increment current_command_line_count before
+ adding partial line to command history (for command-oriented-history
+ because of rl_newline at beginning of function), then reset it to 0
+ before adding the dummy history entry to make sure the dummy entry
+ doesn't get added to previous incomplete command. Partial fix for
+ problem reported by Peng Yu <pengyu.ut@gmail.com>
+
+ 7/24
+ ----
+configure.in
+ - interix: define RECYCLES_PIDS. Based on a report from Michael
+ Haubenwallner <michael.haubenwallner@salomon.at>
+
+ 7/26
+ ----
+jobs.c
+ - make_child: call bgp_delete on the newly-created pid unconditionally.
+ Some systems reuse pids before cycling through an entire set of
+ CHILD_MAX/_SC_CHILD_MAX unique pids. This is no longer dependent
+ on RECYCLES_PIDS. Based on a report from Michael Haubenwallner
+ <michael.haubenwallner@salomon.at>
+
+support/shobj-conf
+ - Mac OS X: drop MACOSX_DEPLOYMENT_TARGET=10.3 from the LDFLAGS. We
+ can finally kill Panther
+
+ 7/28
+ ----
+subst.c
+ - command_substitute: make sure last_made_pid gets reset if make_child
+ fails
+
+execute_cmd.c
+ - execute_command_internal: case cm_simple: decide whether or not to
+ wait_for a child if already_making_children is non-zero, indicates
+ that there is an unwaited-for child. More of fix for bug report
+ from Michael Haubenwallner <michael.haubenwallner@salomon.at>
+
+jobs.c
+ - make_child: call delete_old_job (new_pid) unconditionally, don't
+ bother to check whether or not pid wrap occurred. Rest of fix for
+ bug report from Michael Haubenwallner
+ <michael.haubenwallner@salomon.at>
+
+ 7/29
+ ----
+shell.c
+ - subshell_exit: new function, exits the shell (via call to sh_exit())
+ after calling any defined exit trap
+
+externs.h
+ - subshell_exit: new extern declaration
+
+execute_cmd.c
+ - execute_command_internal: make sure to call subshell_exit for
+ {} group commands executed asynchronously (&). Part of fix for
+ EXIT trap bug reported by Maarten Billemont <lhunath@lyndir.com>
+
+sig.c
+ - reset_terminating_signals: make sure to set termsigs_initialized back
+ to 0, so a subsequent call to initialize_terminating_signals works
+ right. Rest of fix for bug reported by Maarten Billemont
+ <lhunath@lyndir.com>
+
+{execute_cmd,general,jobs,mailcheck,mksyntax,test}.c
+builtins/{cd,fc,pushd,ulimit}.def
+lib/malloc/getpagesize.h
+lib/sh/{clktck,fpurge,inet_aton,mailstat,oslib,pathcanon,pathphys,spell,strerror}.c
+ - make inclusion of <sys/param.h> dependent on HAVE_SYS_PARAM_H
+ consistently
+
+ 8/6
+ ---
+lib/readline/histexpand.c
+ - history_expand_internal: now takes an additional argument saying
+ whether the history expansion occurs within a quoted string, set to
+ the open quote character
+ - history_expand_internal: use new argument instead of checking prev
+ char and initializing quoted_search_delimiter, pass qc directly to
+ get_history_event, where it allows a matching quote to terminate a
+ string defining an event
+ - history_expand: change single-quote handling code so that if
+ history_quotes_inhibit_expansion is 0, single quotes are treated
+ like double quotes
+ - history_expand: change call to history_expand_internal to pass new
+ argument of `"' if double-quoted string, `'' if single-quoted string;
+ this lets history_expand decide what is a quoted string and what
+ is not
+
+ 8/7
+ ---
+configure.in
+ - AC_CANONICAL_BUILD: invoke for later use
+
+lib/readline/macro.c
+ - _rl_prev_macro_key: new function, inverse of _rl_next_macro_key:
+ backs up the index into the current macro by 1
+
+lib/readline/rlprivate.h
+ - _rl_prev_macro_key: extern declaration
+
+
+lib/readline/readline.c
+ - _rl_dispatch_subseq, _rl_subseq_result: don't call _rl_unget_char
+ if we're currently reading from a macro; call _rl_prev_macro_key
+ instead. Fixes bug reported by Clark Wang <clark.wang@oracle.com>
+
+ 8/13
+ ----
+builtins/evalstring.c
+ - evalstring(): new function, wrapper around parse_and_execute.
+ make sure we handle cases where parse_and_execute can call `return'
+ and short-circuit without cleaning up properly. We call
+ parse_and_execute_cleanup() then jump to the previous-saved return
+ location
+
+builtins/common.h
+ - extern declaration for evalstring()
+
+builtins/eval.def
+ - eval_builtin: make sure we handle `eval " ... return"' in contexts
+ where `return' is valid by calling evalstring(). Fixes bug with
+ `eval return' in sourced files reported by Clark Wang
+ <dearvoid@gmail.com>
+
+trap.c
+ - run_pending_traps: call evalstring instead of parse_and_execute.
+ XXX - still needs to handle saving and restoring token state in the
+ presence of `return'; could use unwind_protects for that
+
+builtins/mapfile.def
+ - run_callback: call evalstring instead of parse_and_execute
+
+ 8/15
+ ----
+bashline.c
+ - bash_filename_stat_hook: make sure we don't free local_dirname
+ before using it to canonicalize any expanded filename. Make sure
+ it always points to *dirname and only free it if we're replacing
+ it.
+
+lib/readline/complete.c
+ - append_to_match: make sure we call rl_filename_stat_hook with
+ newly-allocated memory to avoid problems with freeing it twice
+
+ 8/17
+ ----
+variables.c,config-top.h
+ - if ARRAY_EXPORT is defined to 1 when variables.c is compiled, the
+ code that allows indexed arrays to be exported is enabled and
+ included
+
+ 8/19
+ ----
+shell.c
+ - call start_debugger from main() only if dollar_vars[1] != 0 (close
+ enough to a non-interactive shell, since we can be interactive with
+ -i while running a shell script). Fixes oddity reported by
+ Techlive Zheng <techlivezheng@gmail.com>
+
+ 8/20
+ ----
+arrayfunc.c
+ - quote_array_assignment_chars: don't bother quoting if the word has
+ not been marked as an assignment (W_ASSIGNMENT)
+ - quote_array_assignment_chars: turn on W_NOGLOB in the word flags
+ so assignment statements don't undergo globbing. Partial fix for
+ problems reported by Dan Douglas <ormaaj@gmail.com>
+
+ 8/21
+ ----
+command.h
+ - W_NOBRACE: new word flag that means to inhibit brace expansion
+
+subst.c
+ - brace_expand_word_list: suppress brace expansion for words with
+ W_NOBRACE flag
+
+ 8/22
+ ----
+builtins/read.def
+ - read_builtin: don't call dequote_string on what we've read, even if
+ we saw an escape character, unless (input_string && *input_string).
+ We may have escaped an IFS whitespace character. Fixes seg fault
+ reported by <armandsl@gmail.com>
+
+execute_cmd.c
+ - execute_command_internal: set the_printed_command_except trap when
+ about to execute a ( ... ) user subshell. For now, set it only if
+ ERR is trapped; can relax that later. Fixes bug reported by
+ Mike Frysinger <vapier@gentoo.org>
+
+ 8/23
+ ----
+jobs.c
+ - remove references to first_pid and pid_wrap, since we're not using
+ them for anything anymore
+
+ 8/24
+ ----
+subst.c
+ - changes for W_NOBRACE everywhere appropriate: so it can be displayed
+ for debugging, and passed out of expand_word_internal
+
+doc/{bash.1,bashref.texi}
+ - small changes to make it clearer that the = and == operators are
+ equivalent, and will cause pattern matching when used with [[.
+ From a question from Michal Soltys <soltys@ziu.info>
+
+doc/bashref.texi
+ - some small formatting changes from Karl Berry <karl@freefriends.org>
+
+ 8/27
+ ----
+lib/readline/doc/{history,rlman,rluserman}.texi
+ - some small formatting changes from Karl Berry <karl@freefriends.org>
+
+arrayfunc.c
+ - assign_array_element_internal, assign_compound_array_list,
+ unbind_array_element, array_value_internal: changes to make
+ assignment statements to negative indices (a[-1]=2) and unsetting
+ array elements using negative indices (unset 'a[-1]') work.
+ From suggestions by Dennis Williamson <dennistwilliamson@gmail.com>
+ and Chris F. A. Johnson <chris@cfajohnson.com>
+
+subst.c
+ - array_length_reference: changes to make length references to array
+ elements using negative indices (${#a[-1]}) work
+
+ 8/28
+ ----
+doc/{bash.1,bashref.texi}
+ - document new treatment of negative indices to indexed arrays when
+ assigning, referencing, calculating length, and unsetting
+
+ 8/29
+ ----
+shell.c
+ - show_shell_usage: add -l to list of shell invocation options (short
+ for --login). From Red Hat bug 852469
+
+configure.ac
+ - renamed from configure.in, as latest autoconf versions want. Patches
+ Stefano Lattarini <stefano.lattarini@gmail.com>
+
+MANIFEST,Makefile.in,doc/bashref.texi,support/mkconffiles
+ - configure.in -> configure.ac
+
+ 9/1
+ ---
+
+parse.y
+ - read_token_word: allow words like {array[ind]} to be valid redirection
+ words for constructs like {x}<file
+
+redir.c
+ - redir_varassign: bind_var_to_int already handles array assignments,
+ so don't need to do anything more for things like {a[i]}<file
+ - redir_varvalue: changes to allow references to {a[i]} when
+ performing redirections using valid_array_reference and
+ get_array_value. Adds functionality requested most recently by
+ <unknown@vmw-les.eng.vmware.com>
+
+lib/readline/display.c
+ - update_line: if the first difference between the old and new lines
+ is completely before any invisible characters in the prompt, we
+ should not adjust _rl_last_c_pos, since it's before any invisible
+ characters. Fixed in two places
+ - prompt_modechar: return a character indicating the editing mode:
+ emacs (@), vi command (:), or vi insert (+)
+ - _rl_reset_prompt: new function, just calls rl_expand_prompt. Will be
+ inlined, placeholder for more changes
+ - expand_prompt: if show-mode-in-prompt is enabled, add a character to
+ the front of the prompt indicating the editing mode, adjusting the
+ various variables as appropriate to keep track of the number of
+ visible characters and number of screen positions
+
+lib/readline/bind.c
+ - show-mode-in-prompt: new bindable boolean variable, shadowed by
+ _rl_show_mode_in_prompt variable
+ - hack_special_boolean_var: call _rl_reset_prompt when toggling or
+ setting show-mode-in-prompt
+
+lib/readline/readline.c
+ - readline_internal_setup: make sure the correct vi mode keymap is set
+ before expanding the prompt string for the first time
+
+lib/readline/misc.c
+ - rl_emacs_editing_mode: make sure to call _rl_reset_prompt if we're
+ showing the editing mode in the prompt
+
+lib/readline/rlprivate.h
+ - _rl_reset_prompt, _rl_show_mode_in_prompt: extern declarations
+
+lib/readline/vi_mode.c
+ - rl_vi_insertion_mode: call _rl_reset_prompt
+ - rl_vi_movement_mode: call _rl_reset_prompt. Finishes changes for
+ showing mode in prompt string, originally requested by Miroslav
+ Koskar <mkoskar@gmail.com> and most recently by Jordan Michael
+ Ziegler <jziegler@bnl.gov>
+
+doc/bash.1,lib/readline/doc/{readline.3,rluser.texi}
+ - document new show-mode-in-prompt variable, off by default
+
+ 9/3
+ ---
+
+jobs.c
+ - set_childmax: new function, external mechanism for other parts of
+ the shell to set js.c_childmax, the number of saved exited child
+ statuses to remember
+jobs.h
+ - set_childmax: extern declaration
+
+variables.c
+ - CHILD_MAX: new special variable, with sv_childmax function to
+ run when it changes. Setting CHILD_MAX to a value greater than
+ zero but less than some maximum (currently 8192) sets the number of
+ exited child statuses to remember. set_childmax (jobs.c) ensures
+ that the number does not drop below the posix-mandated minimum
+ (CHILD_MAX)
+
+doc/{bash.1,bashref.texi}
+ - CHILD_MAX: document new meaning and action when variable is set
+
+ 9/5
+ ---
+redir.c
+ - redir_varassign: call stupidly_hack_special_variables after
+ assigning fd number to specified variable, so we can use constructs
+ like {BASH_XTRACEFD}>foo. Suggested by Pierre Gaston
+ <pierre.gaston@gmail.com>
+
+ 9/8
+ ---
+expr.c
+ - readtok: invalidate previous contents of `curlval' before freeing
+ and reallocating tokstr (which, chances are, will get the same
+ pointer as before and render curlval inconsistent). Fixes other
+ bug reported by Dan Douglas <ormaaj@gmail.com>
+
+ 9/9
+ ---
+lib/readline/complete.c
+ - rl_username_completion_function: protect call to setpwent() with
+ #ifdef (HAVE_GETPWENT)/#endif. Fixes bug reported by
+ Gerd Hofmann <gerd.hofmann.nbg@googlemail.com>
+
+lib/readline/display.c
+ - rl_message: second and subsequent calls to rl_message can result in
+ local_prompt being overwritten with new values (e.g., from the
+ successive calls displaying the incremental search string). Need
+ to free before overwriting if it's not the same as the value saved
+ in saved_local_prompt. Fixes memory leak reported by
+ Wouter Vermaelen <vermaelen.wouter@gmail.com>
+
+lib/readline/{terminal.c,rlprivate.h}
+ - move CUSTOM_REDISPLAY_FUNC and CUSTOM_INPUT_FUNC defines from
+ terminal.c to rlprivate.h so other files can use them
+
+expr.c
+ - expr_streval: if noeval is non-zero, just return 0 right away,
+ short-circuiting evaluation completely. readtok will leave curtok
+ set correctly without re-entering the evaluator at all. Rest of
+ fix for bug reported by Dan Douglas <ormaaj@gmail.com>
+
+ 9/11
+ ----
+
+parse.y
+ - parse_comsub: make sure the `reserved word ok in this context' flag
+ is preserved after we read `do' followed by whitespace. Fixes bug
+ reported by Benoit Vaugon <benoit.vaugon@gmail.com>
+
+ 9/13
+ ----
+configure.ac,config.h.in
+ - enable-direxpand-default: new configure option, turns the `direxpand'
+ shell option on by default
+
+bashline.c
+ - dircomplete_expand, dircomplete_expand_relpath: initialize to 1 if
+ DIRCOMPLETE_EXPAND_DEFAULT is defined and non-zero
+
+doc/bashref.texi
+ - enable-direxpand-default: document new configure option
+
+ 9/14
+ ----
+shell.c
+ - --protected: make option valid only when wordexp is compiled into
+ the shell. Fix from Roman Rakus <rrakus@redhat.com>
+
+configure.ac
+ - HP NonStop (*-nsk*): compile --without-bash-malloc. Change from
+ Joachim Schmitz <jojo@schmitz-digital.de>
+
+ 9/16
+ ----
+subst.c,execute_cmd.c,lib/glob/sm_loop.c,lib/sh/shquote.c
+ - minor code cleanups from Joachim Schmitz <jojo@schmitz-digital.de>
+
+lib/readline/colors.h
+ - workaround for HP NonStop compiler issue with <stdbool.h> from
+ Joachim Schmitz <jojo@schmitz-digital.de>
+
+ 9/17
+ ----
+builtins/printf.def
+ - printf_builtin: handle localtime returning NULL, as can happen when
+ encountering overflow. Bug report and initial fix from
+ Eduardo A. Bustamante López <dualbus@gmail.com>
+
+doc/{bash.1,bashref.texi}
+ - emphasize that brace expansion using character ranges ({a..c}) acts
+ as if the C locale were in use. Prompted by message from
+ Marcel Giannelia <info@skeena.net>
+
+ 9/20
+ ----
+lib/sh/wcsnwidth.c
+ - wcsnwidth: new function, variant of wcwidth, returns the number of
+ wide characters from a string that will be displayed to not exceed
+ a specified max column position
+
+ 9/21
+ ----
+builtins/help.def
+ - show_builtin_command_help: break code that displays the short-doc
+ for each builtin in two columns into a new function: dispcolumn
+ - wdispcolumn: multibyte-char version of dispcolumn; uses wide
+ chars and printf "%ls" format. Fixes problem reported by
+ Nguyá»n Thái Ngá»c Duy <pclouds@gmail.com>
+
+ 9/22
+ ----
+execute_cmd.c
+ - execute_disk_command: before running the command-not-found hook,
+ call kill_current_pipeline() to make sure we don't add processes
+ to an existing pipeline or wait for processes erroneously
+
+ 9/23
+ ----
+lib/readline/input.c
+ - rl_input_available_hook: new hook function, called from
+ _rl_input_available (or _rl_input_queued) to return whether or not
+ input is available wherever the input source is
+
+lib/readline/doc/rltech.texi
+ - rl_input_available_hook: document
+
+ 9/27
+ ----
+lib/glob/sm_loop.c:
+ - GMATCH: after one or more `*', an instance of ?(x) can match zero or
+ 1 times (unlike ?, which has to match one character). The old code
+ failed if it didn't match at least once. Fixes `a*?(x)' bug.
+ - GMATCH: if we hit the end of the search string, but not the end of
+ the pattern, and the rest of the pattern is something that can
+ match the NUL at the end of the search string, we should successfully
+ match. Fixes `a*!(x)' bug reported by <hans1worst@gmail.com>
+
+ 10/2
+ ----
+command.h
+ - add c_lock member to coproc structure for future use to tell who is
+ manipulating it
+
+execute_cmd.c
+ - execute_coproc: block SIGCHLD while parent is forking coproc
+ process and adding pid to sh_coproc struct to avoid race condition
+ where child is reaped before the pid is assigned and the coproc is
+ never marked as having died. Fixes race condition identified by
+ Davide Baldini <baldiniebaldini@gmail.com>
+ - add assignments to c_lock member of struct coproc in various
+ functions that manipulate it; was used to identify race condition
+ - coproc_pidchk: don't call coproc_dispose to avoid using malloc and
+ other functions in a signal handler context
+ - coproc_dispose: call BLOCK_SIGNAL/UNBLOCK_SIGNAL for SIGCHLD while
+ manipulating the sh_coproc struct
+
+ 10/6
+ ----
+lib/readline/complete.c
+ - rl_display_match_list: if printing completions horizontally, don't
+ bother with spacing calculations if limit == 1, which means we are
+ printing one completion per line no matter what. Fixes bug
+ reported by David Kaasen <kaasen@nvg.ntnu.no>
+
+ 10/7
+ ----
+builtins/declare.def
+ - declare_internal: add error checking for nameref attribute and
+ variable assignments: self-references, attempts to make an array
+ variable a nameref
+
+subst.c
+ - parameter_brace_expand: handle parameter_brace_expand_word returning
+ &expand_param_fatal or &expand_param_error and return the appropriate
+ error value
+ - parameter_brace_expand_word: if a nameref variable's value is not a
+ valid identifier, return an error
+ - param_expand: if a nameref variable's value is not a valid identifier,
+ return an error
+
+test.c
+ - unary_operator: add new -R variable, returns true if variable is set
+ and has the nameref attribute. From ksh93
+
+builtins/test.def
+ - add -R to description of conditional commands for help test
+
+doc/{bash.1,bashref.texi}
+ - document new -R unary conditional operator
+
+ 10/13
+ -----
+trap.c
+ - check_signals_and_traps: new function, convenience function for the
+ rest of the shell to check for pending terminating and interrupt
+ signals, and to check for and process any pending traps
+ - any_signals_trapped: new function, returns non-zero if any signals
+ are trapped and -1 if not
+
+trap.h
+ - extern declaration for check_signals_and_traps
+
+bashline.c
+ - bashline_reset: make sure we reset the event hook
+ - bash_event_hook: call check_signals_and_traps instead of just
+ checking for terminating signals so we can run pending traps and
+ react to interrupts, and reset the event hook when we're done
+
+
+ 10/14
+ -----
+trap.c
+ - trap_handler: if executing in a readline signal handler context,
+ call bashline_set_event_hook to install bash_event_hook to process
+ the signal (if bash cares about it)
+
+sig.c
+ - sigint_sighandler: call bashline_set_event_hook to set the event
+ hook if we're executing in a readline signal handler context
+
+lib/readline/input.c
+ - rl_getc: call RL_CHECK_SIGNALS if read returns -1/EINTR and the caught
+ signal is SIGINT or SIGQUIT rather than waiting until the next time
+ around the loop
+ - rl_getc: call rl_event_hook after calling RL_CHECK_SIGNALS to allow
+ an application signal handler to set the event hook in its own
+ signal handler (e.g., like bash trap_handler or sigint_sighandler)
+
+
+parse.y
+ - yy_readline_get: don't set interrupt_immediately before we call
+ readline(). Inspired by report from lanshun zhou
+ <zls.sogou@gmail.com>
+
+input.c
+ - getc_with_restart: add call to run_pending_traps after call to
+ CHECK_TERMSIG
+
+lib/sh/zread.c
+ - zread: call check_signals_and_traps if read() returns -1/EINTR
+ instead of just ignoring the EINTR and deferring handling any
+ signal that generated it
+
+builtins/mapfile.def
+ - mapfile: don't set interrupt_immediately before calling zgetline()
+ (which uses zread internally)
+
+builtins/read.def
+ - read_builtin: don't set interrupt_immediately before calling zread
+ (moved code around so that it was only being set right around calls
+ to zread to avoid signal handler conflicts). Inspired by report
+ from lanshun zhou <zls.sogou@gmail.com>
+ - edit_line: don't set interrupt_immediately around call to readline()
+ - include shmbutil.h
+ - read_builtin: don't call read_mbchar unless is_basic(c) returns
+ false for the character we just read
+
+ 10/15
+ -----
+sig.c
+ - throw_to_top_level: if interrupt_state is non-zero, make sure that
+ last_command_exit_value reflects 128+SIGINT if it's not already
+ greater than 128
+
+ 10/20
+ -----
+builtins/wait.def
+ - WAIT_RETURN: set wait_signal_received back to 0 for the potential
+ next call to wait
+
+quit.h
+ - CHECK_WAIT_INTR: macro to check whether trap_handler handled a
+ signal and set wait_signal_received; longjmp to wait_intr_buf in
+ that case
+
+jobs.c
+ - wait_for, waitchld: call CHECK_WAIT_INTR at the same places we call
+ CHECK_TERMSIG to check for terminating signals
+ - wait_sigint_handler: don't longjmp out of the wait builtin unless
+ interrupt_immediately is set; otherwise just SIGRETURN from the
+ handler
+ - wait_sigint_handler: if interrupt_immediately not set, but we are
+ executing in the wait builtin and SIGINT is not trapped, treat it
+ as a `normally received' SIGINT: restore the signal handler and
+ send SIGINT to ourselves
+ - waitchld: when in posix mode and running SIGCHLD traps, don't longjmp
+ to wait_intr_buf (and let wait be interrupted) if we're running from
+ a signal handler. Wait for CHECK_WAIT_INTR to do the longjmp.
+ run_pending_traps will run the SIGCHLD trap later
+
+nojobs.c
+ - reap_zombie_children, wait_for_single_pid, wait_for: call
+ CHECK_WAIT_INTR where we call CHECK_TERMSIG
+ - wait_sigint_handler: don't longjmp out of the wait builtin unless
+ interrupt_immediately is set; otherwise just SIGRETURN from the
+ handler
+
+trap.c
+ - trap_handler: make sure wait_signal_received is set if the wait
+ builtin is executing, and only longjmp if interrupt_immediately is
+ set. This whole set of fixes was prompted by report from
+ lanshun zhou <zls.sogou@gmail.com>
+
+ 10/24
+ -----
+lib/glob/glob.c
+ - glob_filename: only check directory_name for globbing chars if
+ it's of non-zero length
+
+lib/sh/strchrnul.c
+ - new simpler implementation
+
+subst.c
+ - command_substitute: call set_shellopts after turning off errexit
+ in subshells so it's reflected in $SHELLOPTS
+
+ 11/7
+ ----
+builtins/evalstring.c
+ - parse_and_execute: treat ERREXIT case like reader_loop does: set
+ variable_context to 0 before longjmping back to top_level. Don't
+ run the unwind-protect context to avoid side effects from popping
+ function contexts. Part of fix for problem reported by Nikolai
+ Kondrashov <nikolai.kondrashov@redhat.com>
+
+execute_cmd.c
+ - execute_simple_command: call unlink_fifo_list only if this is the
+ last element of a pipeline (or not in a pipeline), rather than for
+ every child. Fixes difference in behavior between /dev/fd and
+ FIFOs reported by Zev Weiss <zev@bewilderbeest.net>
+ - execute_null_command: do the same thing in the parent branch after
+ make_child
+
+ 11/14
+ -----
+subst.c
+ - parameter_brace_expand: a variable is null if it's special ($@, $*),
+ the expansion occurs within double quotes, and the expansion turns
+ into a quoted null. Fixes debian bug 692447 reported by
+ Matrosov Dmitriy <sgf.dma@gmail.com>
+
+jobs.c
+ - run_sigchld_trap: make sure `running_trap' sentinel is set
+ appropriately
+ - waitchld: only run the sigchld trap if we're not in a signal
+ handler, not running a trap, and executing the wait builtin.
+ Otherwise, queue for later handling. We still run one instance
+ of the trap handler per exited child. Bulk of fix for bug
+ reported by Elliott Forney <idfah@cs.colostate.edu>
+
+trap.c
+ - queue_sigchld_trap: set catch_flag so run_pending_traps notices,
+ and set trapped_signal_received for completeness. Rest of fix
+ for bug reported by Elliott Forney <idfah@cs.colostate.edu>
+
+lib/malloc/malloc.c
+ - block_signals: renamed to _malloc_block_signals, made public
+ - unblock_signals: renamed to _malloc_unblock_signals, made public
+
+lib/malloc/imalloc.h
+ - extern declarations for _malloc_{un,}block_signals
+
+lib/malloc/table.c
+ - mregister_alloc, mregister_free: block signals around table
+ manipulation
+
+ 11/15
+ -----
+trap.c
+ - run_pending_traps: set SIG_INPROGRESS flag around calls to
+ run_sigchld_handler so other parts of the shell know that the
+ SIGCHLD trap handler is executing
+ - run_pending_traps: if we get a situation where we are looking at
+ running a SIGCHLD trap but the trap string is IMPOSSIBLE_TRAP_HANDLER
+ and the SIG_INPROGRESS flag is set, just skip it. This is possible
+ if run_pending_traps is called from a SIGCHLD trap handler run by
+ run_sigchld_trap
+
+doc/bash.1,lib/readline/doc/{rluser.texi,readline.3}
+ - corrected description of the effect of `set history-size 0'. Report
+ from Vesa-Matti J Kari <vmkari@cc.helsinki.fi>
+
+include/stdc.h
+ - CPP_STRING: new define, replaces __STRING
+
+lib/malloc/{malloc.c,imalloc.h}
+ - replace __STRING with CPP_STRING
+
+ 11/16
+ -----
+lib/readline/bind.c
+ - sv_histsize: if argument evaluates to a value < 0, unstifle the
+ history
+
+ 11/22
+ -----
+redir.c
+ - do_redirection_internal: if we have REDIR_VARASSIGN set in the
+ redirection flags and we set up `redirector' using fcntl or dup2,
+ don't add a redirect to make sure it stays open. Let the
+ script programmer manage the file handle. Fixes bug reported by
+ Sam Liddicott <sam@liddicott.com>
+
+ 11/24
+ -----
+jobs.c
+ - wait_for_any_job: new function, waits for an unspecified background
+ job to exit and returns its exit status. Returns -1 on no background
+ jobs or no children or other errors. Calls wait_for with new
+ sentinel value ANY_PID
+ - wait_for: changes to handle argument of ANY_PID: don't look up or
+ try to modify the child struct, only go through the wait loop once.
+ Return -1 if waitpid returns no children
+
+jobs.h
+ - ANY_PID: new define
+
+builtins/wait.def
+ - new option: -n. Means to wait for the next job and return its exit
+ status. Returns 127 if there are no background jobs (or no
+ children). Feature most recently requested by Elliott Forney
+ <idfah@cs.colostate.edu>
+
+doc/{bash.1,bashref.texi}
+ - document new `wait -n' option
+
+execute_cmd.c
+ - execute_command_internal: save make_command_string () result in a
+ temp variable before calling savestring() on it; avoids evaluating
+ make_command_string() result twice. Fix from John E. Malmberg
+ <wb8tyw@qsl.net>
+
+ 11/28
+ -----
+
+builtins/declare.def
+ - declare_internal: if an array variable is declared using `declare -a'
+ or `declare -A', but not assigned a value, set the `invisible'
+ attribute so the variable does not show up as set. Fix for bug
+ about variable initialization reported by Tim Friske <me@timfriske.com>
+
+builtins/{mapfile,read}.def
+ - after calling find_or_make_array_variable, make sure the invisible
+ flag is turned off, in case the variable was declared previously
+ using `declare -a' or `declare -A'. Side effect of above change to
+ declare_internal
+
+subst.c
+ - shell_expand_word_list: handle the W_ASSNGLOBAL flag and put -g into
+ the list of options passed to make_internal_declare as appropriate.
+ Fix for bug reported by Tim Friske <me@timfriske.com>
+
+ 11/30
+ -----
+test.c
+ - unary_op: make sure -v and -n check that the variable is not marked
+ as invisible before calling var_isset. Fix for bug reported by Tim
+ Friske <me@timfriske.com>
+
+ 12/2
+ ----
+subst.c
+ - process_substitute: turn off the `expanding_redir' flag, which
+ controls whether or not variables.c:find_variable_internal uses the
+ temporary environment to find variables. We want to use the
+ temp environment, since we don't have to worry about order of
+ evaluation in a subshell. Fixes bug reported by Andrey Borzenkov
+ <arvidjaar@gmail.com>
+
+ 12/4
+ ----
+lib/glob/glob.c
+ - glob_filename: changes to avoid null filenames and multiple entries
+ returned for patterns like **/** (globstar enabled). Fixes bug
+ reported by Ulf Magnusson <ulfalizer@gmail.com>
+
+ 12/10
+ -----
+lib/glob/glob.c
+ - glob_filename: finish up a series of changes to make globstar-style
+ globbing more efficient, avoid more duplicate filenames, and be more
+ compatible with other shells that implement it
+ o collapse a sequence of **/**/** to one **
+ o note when the directory name is all ** or ends in ** so we
+ can treat it specially when the filename is **
+ All inspired by report from Andrey Borzenkov <arvidjaar@gmail.com>
+
+lib/sh/zread.c
+ - zreadn: new function, like zread, but takes an additional argument
+ saying how many bytes to read into the local buffer. Can be used to
+ implement `read -N' without so many one-byte calls to zreadc. Code
+ from Mike Frysinger <vapier@gentoo.org>
+
+ 12/12
+ -----
+lib/glob/sm_loop.c
+ - PATSCAN (glob_patscan): if passed string already points to end of
+ pattern, return NULL immediately. Fixes problem with
+ extglob_skipname reported by Raphaël Droz <raphael.droz@gmail.com>
+
+ 12/13
+ -----
+execute_cmd.c
+ - execute_coproc: handle the command's exit status being inverted
+ (an oversight). Fixes bug reported by DJ Mills
+ <danielmills1@gmail.com> and Andreas Schwab <schwab@linux-m68k.org>
+
+ 12/14
+ -----
+lib/readline/readline.c
+ - bind_arrow_keys_internal: add MINGW key bindings for Home, End,
+ Delete, and Insert keys. Fix from Pierre Muller
+ <pierre.muller@ics-cnrs.unistra.fr>
+
+builtins/printf.def
+ - printf_builtin: '%()T' conversion: if there is no argument supplied,
+ behave as if -1 had been supplied (current time). ksh93-like feature
+ suggested by Clark Wang <dearvoid@gmail.com>
+
+doc/{bash.1,bashref.texi}
+ - document new printf %()T default argument behavior
+
+ 12/15
+ -----
+lib/readline/display.c
+ - displaying_prompt_first_line: new variable, indicates whether or
+ not the first line of output is displaying the prompt. Always true
+ in normal mode, sometimes false in horizontal scrolling mode
+ - rl_redisplay: set displaying_prompt_first_line to true unless we
+ are in horizontal mode; set to false in horizontal mode if the left
+ margin of the displayed line is greater than the end of the prompt
+ string
+ - rl_redisplay: when in horizontal scroll mode, don't adjust
+ _rl_last_c_pos by the wrap offset unless the line is displaying
+ a prompt containing invisible chars
+ - update line: don't adjust _rl_last_c_pos by the wrap offset unless
+ the line is displaying a prompt containing invisible chars
+ - update_line: if shrinking the line by reducing the number of
+ displayed characters, but we have already moved the cursor to the
+ beginning of the line where the first difference starts, don't
+ try to delete characters
+
+builtins/read.def
+ - unbuffered_read: set to 2 if invoked as `read -N'
+ - if unbuffered_read is set to 2, compute the number of chars we
+ need to read and read that many with zreadn. Posix mode still
+ uses zreadintr. Code from Mike Frysinger <vapier@gentoo.org>
+
+doc/{bash.1,bashref.texi}
+ - read: make it clear that if read times out, it saves any input
+ read to that point into the variable arguments. Report from
+ Fiedler Roman <Roman.Fiedler@ait.ac.at>
+
+subst.c
+ - command_substitute: change direct assignment of exit_immediately_on_error
+ to use change_flag ('e', FLAG_OFF) instead
+
+flags.c
+ - use errexit_flag as the variable modified by changes to the -e
+ option, reflect those changes to exit_immediately_on_error
+
+execute_cmd.c
+ - execute_builtin: new global variable, builtin_ignoring_errexit, set
+ to 0 by default and set to 1 if eval/source/command executing in a
+ context where -e should be ignored
+ - execute_builtin: set exit_immediately_on_error to errextit_flag
+ after executing eval/source/command in a context where -e should
+ be ignored
+
+flags.c
+ - if builtin_ignoring_errexit is set, changes to errexit_flag are
+ not reflected in the setting of exit_immediately_on_error. Fixes
+ bug reported by Robert Schiele <rschiele@gmail.com>
+
+ 12/23
+ -----
+include/posixjmp.h
+ - setjmp_nosigs: new define, call setjmp in such a way that it will
+ not manipulate the signal mask
+
+{expr,test,trap}.c
+ - setjmp_nosigs: call instead of setjmp; don't need to manipulate
+ signal mask
+
+builtins/read.def
+ - read_builtin: setjmp_nosigs: call instead of setjmp; don't need
+ to manipulate signal mask
+
+builtins/evalstring.c:
+ - parse_and_execute: setjmp_nosigs: call instead of setjmp; don't need
+ to manipulate signal mask
+ - parse_string: setjmp_nosigs: call instead of setjmp; don't need
+ to manipulate signal mask
+ - parse_and_execute: save and restore the signal mask if we get a
+ longjmp that doesn't cause us to return or exit (case DISCARD)
+
+ 12/24
+ -----
+general.c
+ - bash_tilde_expand: only set interrupt_immediately if there are no
+ signals trapped; we want to jump to top level if interrupted but
+ not run any trap commands
+
+ 12/25
+ -----
+jobs.c
+ - run_sigchld_trap: no longer set interrupt_immediately before calling
+ parse_and_execute, even if this is no longer run in a signal handler
+ context
+
+input.c
+ - getc_with_restart: add call to QUIT instead of CHECK_TERMSIG
+
+parse.y
+ - yy_stream_get: now that getc_with_restart calls QUIT, don't need to
+ set interrupt_immediately (already had call to run_pending_traps)
+
+execute_cmd.c
+ - execute_subshell_builtin_or_function,execute_function,execute_in_subshell:
+ setjmp_nosigs: call instead of setjmp when saving return_catch; don't
+ need to manipulate signal mask
+ - execute_subshell_builtin_or_function,execute_in_subshell:
+ setjmp_nosigs: call instead of setjmp where appropriate when saving
+ top_level; don't need to manipulate signal mask if we're going to
+ exit right away
+
+subst.c
+ - command_substitute: setjmp_nosigs: call instead of setjmp when saving
+ return_catch; don't need to manipulate signal mask
+ - command_substitute: setjmp_nosigs: call instead of setjmp where
+ appropriate when saving top_level; don't need to manipulate signal
+ mask if we're going to exit right away
+
+trap.c
+ - run_exit_trap: setjmp_nosigs: call instead of setjmp when saving
+ return_catch; don't need to manipulate signal mask
+ - run_exit_trap: setjmp_nosigs: call instead of setjmp where
+ appropriate when saving top_level; don't need to manipulate signal
+ mask if we're going to exit right away
+ - _run_trap_internal: setjmp_nosigs: call instead of setjmp when saving
+ return_catch; don't need to manipulate signal mask
+
+builtins/evalfile.c
+ - _evalfile: setjmp_nosigs: call instead of setjmp when saving
+ return_catch; don't need to manipulate signal mask
+
+builtins/evalstring.c
+ - evalstring: setjmp_nosigs: call instead of setjmp when saving
+ return_catch; don't need to manipulate signal mask
+
+shell.c
+ - main: setjmp_nosigs: call instead of setjmp where appropriate when
+ saving top_level; don't need to manipulate signal mask if we're
+ going to exit right away
+ - run_one_command: setjmp_nosigs: call instead of setjmp where
+ appropriate when saving top_level; don't need to manipulate signal
+ mask if we're going to exit right away
+ - run_wordexp: setjmp_nosigs: call instead of setjmp where
+ appropriate when saving top_level; don't need to manipulate signal
+ mask if we're going to exit right away
+
+eval.c
+ - reader_loop: save and restore the signal mask if we get a longjmp
+ that doesn't cause us to return or exit (case DISCARD)
+
+ 12/26
+ -----
+parse.y
+ - shell_input_line_{index,size,len}: now of type size_t; in some cases
+ the unsigned property makes a difference
+ - STRING_SAVER: saved_line_{size,index} now of type size_t
+ - shell_getc: don't allow shell_input_line to grow larger than SIZE_MAX;
+ lines longer than that are truncated until read sees a newline;
+ addresses theoretical buffer overflow described by Paul Eggert
+ <eggert@cs.ucla.edu>
+ - set_line_mbstate: size_t changes like shell_getc
+ - shell_getc: if shell_input_line is larger than 32K, free it and
+ start over to avoid large memory allocations sticking around
+
+variables.c
+ - bind_global_variable: new function, binds value to a variable in
+ the global shell_variables table
+
+variables.h
+ - bind_global_variable: new extern declaration
+
+builtins/declare.def
+ - declare_internal: if -g given with name=value, but variable is not
+ found in the global variable table, make sure to call
+ bind_global_variable so the variable is created and modified at
+ global scope. Fixes a bug where declare -g x=y could modify `x'
+ at a previous function scope
+
+command.h
+ - W_ASSIGNARRAY: new word flag, compound indexed array assignment
+
+subst.h
+ - ASS_MKGLOBAL: new assignment flag, forcing global assignment even in
+ a function context, used by declare -g
+
+execute_cmd.c
+ - fix_assignment_words: set W_ASSIGNARRAY flag if -a option given to
+ declaration builtin
+
+subst.c
+ - do_assignment_internal: explicitly handle case where we are
+ executing in a function and we want to create a global array or
+ assoc variable
+ - shell_expand_word_list: call make_internal_declare if -a option
+ given to declaration builtin (W_ASSIGNARRAY); handle -g option with
+ it (W_ASSNGLOBAL). Fixes inconsistency noticed by Vicente Couce
+ Diaz <vituko@gmail.com>, where declare -ag foo=(bar) could modify
+ array variable foo at previous function scope, not global scope
+
+ 12/27
+ -----
+bashline.c
+ - Minix needs the third argument to tputs to be a void funtion taking
+ an int argument, not an int-returning function. Fix from
+ John E. Malmberg <wb8tyw@qsl.net> as part of VMS bash port
+
+ 12/29
+ -----
+configure.ac,version.c,patchlevel.h
+ - bash-4.3-devel: new version, new shell compatibility level (43)
+
+subst.c
+ - parameter_brace_patsub: put the bash-4.2 code back in from the
+ change of 3/3 that runs the replacement string through quote
+ removal, make it dependent on shell_compatibility_level <= 42
+
+builtins/shopt.def
+ - compat42: new shopt option
+ - set_compatibility_level: change logic to set and unset various
+ compat variables and shell_compatibility_level
+
+COMPAT
+ - new documentation for bash-4.3 compatibility changes
+
+doc/{bash.1,bashref.texi}
+ - compat42: document new shopt option
+
+builtins/shopt.def
+ - set_compatibility_opts: new function, sets the various shopt
+ compat variables based on the value of shell_compatibility_level
+
+builtins/common.h
+ - set_compatibility_opts: new extern declaration
+
+variables.c
+ - BASH_COMPAT: new special variable; sets the shell compatibility
+ level. Accepts values in decimal (4.2) or integer (42) form;
+ Unsetting variable, setting it to empty string, or setting it to
+ out-of-range value sets the shell's compatibility level to the
+ default for the current version. Valid values are 3.1/31 through
+ the current version
+ - sv_shcompat: new function implementing logic for BASH_COMPAT
+
+variables.h
+ - sv_shcompat: new extern declaration
+
+doc/{bash.1,bashref.texi}
+ - BASH_COMPAT: description of new variable
+
+lib/readline/complete.c
+ - _rl_colored_stats: default back to 0 for 4.3 release branch
+
+ 1/5/2013
+ --------
+quit.h
+ - remove spurious call to itrace in CHECK_WAIT_INTR
+
+bashline.c
+ - bash_event_hook: if we're going to jump to top_level, make sure we
+ clean up after readline() by calling rl_cleanup_after_signal().
+ Fixes bug reported against devel branch by Raphaël Droz
+ <raphael.droz@gmail.com>
+ - bash_event_hook: reset the event hook before checking for signals
+ or traps in case we longjmp
+
+doc/{bash.1,bashref.texi}
+ - small additions to the set -e section to make it more clear that
+ contexts where -e is ignored extend to compound commands as well
+ as shell functions
+
+lib/readline/readline.h
+ - rl_signal_event_hook: new extern declaration
+
+lib/readline/input.c
+ - rl_signal_event_hook: new variable, hook function to call when a
+ function (currently just read(2)) is interrupted by a signal and
+ not restarted
+ - rl_getc: call rl_signal_event_hook instead of rl_event_hook
+
+lib/readline/doc/rltech.texi
+ - rl_signal_event_hook: document new function
+
+bashline.c
+ - changes to set rl_signal_event_hook instead of rl_event_hook
+
+lib/readline/readline.h
+ - change readline version numbers to 6.3
+
+ 1/6
+ ---
+doc/{bash.1,bashref.texi}
+ - a couple of changes to the descriptions of the ERR trap and its
+ effects based on a message from Rob Nagler <nagler@bivio.biz>
+
+ 1/9
+ ---
+expr.c
+ - expassign: invalidate curlval before freeing and NULLing tokstr to
+ avoid aliasing issues. Fixes bug reported by Eduardo A. Bustamante
+ López<dualbus@gmail.com> and Dan Douglas <ormaaj@gmail.com>
+
+braces.c
+ - array_concat: don't be so aggressive in trying to short-circuit. We
+ can only short-circuit if we have a single-element array where the
+ element is an empty string (array[0] == "" array[1] = 0x0). Existing
+ practice requires us to replicate arrays and prefix or append empty
+ strings. Fixes bug reported by Eduardo A. Bustamante López
+ <dualbus@gmail.com>
+
+ 1/11
+ ----
+execute_cmd.c
+ - execute_builtin: since mapfile uses evalstring() to run its callbacks
+ internally, just like eval, so it needs to handle the case where the
+ temp environment given to mapfile persists throughout the entire
+ set of callback commands. This might be a problem with trap also, but
+ trap isn't run in the same way. Fixes bug reported by Dan Douglas
+ <ormaaj@gmail.com>
+
+ 1/13
+ ----
+redir.c
+ - redirection_error: before expanding the redirection word (if
+ expandable_redirection_filename returns true), disable command
+ substitution during expansion. Fixes bug reported by Dan Douglas
+ <ormaaj@gmail.com>
+
+subst.c
+ - expand_word_internal: case '\\': if the next character is an IFS
+ character, and the expansion occurs within double quotes, and the
+ character is not one for which backslash retains its meaning, add
+ the (escaped) '\' and the (escaped) character. Fixes bug reported
+ by Dan Douglas <ormaaj@gmail.com>
+
+ 1/15
+ ----
+builtins/cd.def
+ - cd_builtin: make sure call to internal_getopt handles -e option.
+ Fixes bug reported by <mashimiao.fnst@cn.fujitsu.com>
+
+ 1/17
+ ----
+subst.c
+ - expand_word_list_internal: make sure tempenv_assign_error is
+ initialized to 0
+
+execute_cmd.c
+ - execute_simple_command: make sure tempenv_assign_error is reset to 0
+ after it's tested to see if an error should force the shell to exit.
+ Fixes problem where a the failure of a tempenv assignment preceding
+ a non-special builtin `sticks' and causes the next special builtin
+ to exit the shell. From a discussion on bug-bash started by
+ douxin <wq-doux@cn.fujitsu.com>
+
+ 1/20
+ ----
+subst.c
+ - parameter_brace_expand_rhs: call stupidly_hack_special_variables
+ after assigning with ${param[:]=word} even if IFS is changing.
+ Suggested by Dan Douglas <ormaaj@gmail.com> [TENTATIVE, needs work
+ on IFS side effects]
+
+command.h
+ - W_GLOBEXP (which was unused) is now W_SPLITSPACE (which isn't used
+ yet)
+
+{execute_cmd,subst,variables}.c
+ - removed all code that mentioned W_GLOBEXP
+ - removed mention of gnu_argv_flags and code that set it
+
+ 1/22
+ ----
+subst.c
+ - param_expand: set W_SPLITSPACE if we expand (unquoted) $* and
+ IFS is unset or null so we can be sure to split this on spaces
+ no matter what happens with IFS later
+ - expand_word_internal: note that param_expand returns W_SPLITSPACE
+ in the returned word flags and keep track of that state with
+ `split_on_spaces'
+
+ 1/23
+ ----
+subst.c
+ - expand_word_internal: if split_on_spaces is non-zero, make sure
+ we split `istring' on spaces and return the resultant word. The
+ previous expansions should have quoted spaces in the positional
+ parameters where necessary. Suggested by Dan Douglas
+ <ormaaj@gmail.com>
+
+execute_cmd.c
+ - execute_command_internal: make sure any subshell forked to run a
+ group command or user subshell at the end of a pipeline runs any
+ EXIT trap it sets. Fixes debian bash bug 698411
+ http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=698411
+
+subst.c
+ - shell_expand_word_list: fix code that creates args for and calls
+ make_internal_declare to avoid calling it twice (missing `else'
+ in 12/26 change)
+ - do_assignment_internal: fix code from 12/26 change to fix problem
+ where an existing assoc variable could be converted to an array
+ without checking `mkassoc'
+
+ 1/24
+ ----
+builtins/evalfile.c
+ - _evalfile: add missing `close (fd)' calls before returning to
+ avoid fd leaks. Bug and fix from Roman Rakus <rrakus@redhat.com>
+
+ 1/25
+ ----
+builtins/read.def
+ - read_builtin: don't try to play tricks with the top of the unwind-
+ protect stack after read gets a SIGALRM; save input_string to new
+ memory, run the stack, then restore input_string and assign the
+ variables. Part of fix for bug reported by konsolebox
+ <konsolebox@gmail.com>; the rest of the fix is with the changes in
+ trap and signal handling and doing away with interrupt_immediately
+
+ 1/26
+ ----
+redir.c
+ - redirection_expand, write_here_string, write_here_document: before
+ calling any of the word expansion functions, after setting
+ expanding_redir to 1 (which bypasses the temp environment in the
+ variable lookup functions), call sv_ifs to reset the cached IFS-
+ related variables set by subst.c:setifs(). This ensures that
+ redirections will not get any IFS values that are set in the
+ temporary environment, as Posix specifies. Then, after the word
+ expansions, after resetting expanding_redir to 0, call sv_ifs
+ again to make sure the cached IFS values are set from any
+ assignments in the temporary environment. We force executing_builtin
+ to 1 to `fool' the variable lookup functions into using any temp
+ environment, then reset it to its old value after sv_ifs returns.
+ This is what allows read() to use the (cached) IFS variables set
+ in the temp environment. Fixes inconsistency reported by Dan Douglas
+ <ormaaj@gmail.com>
+
+ 1/29
+ ----
+lib/readline/display.c
+ - update_line: fix off-by-one error when updating vis_lbreaks array
+ in a multibyte locale that occurs when moving multibyte chars from
+ one line down to another. Bug report and fix from Egmont
+ Koblinger <egmont@gmail.com>
+
+ 1/30
+ ----
+configure.ac
+ - changed version to 4.3-alpha
+
+redir.c
+ - redir_open: handle open returning -1/EINTR, which seems to happen
+ a lot with FIFOs and SIGCHLD, and call QUIT to handle other
+ signals that can interrupt open(2). Bug report and initial fix
+ from Mike Frysinger <vapier@gentoo.org>
+
+ 1/31
+ ----
+subst.c
+ - parameter_brace_expand: make sure to propagate the PF_ASSIGNRHS flag
+ to parameter_brace_expand_word
+ - parameter_brace_expand_word: make sure that if the PF_ASSIGNRHS flag
+ is set and we are expanding ${a[@]} or ${a[*]} we set quoted to
+ include Q_DOUBLE_QUOTES before calling array_value_internal, mirroring
+ what we do for $@ and $*. Fixes inconsistency reported by Dan
+ Douglas <ormaaj@gmail.com>
+
+configure.ac
+ - use AC_CHECK_TOOL instead of AC_CHECK_PROG to check for ar, since it
+ will find $host-prefixed versions of utilities. Report and fix from
+ Mike Frysinger <vapier@gentoo.org>
+
+builtins/setattr.def
+ - set_var_attribute: check whether bind_variable (called when the
+ variable whose attributes are being modified is found in the temp
+ environment) just modified a read-only global variable, and don't
+ bother marking the temporary variable for propagation if so. The
+ propagation is superfluous and will result in a strange error
+ message
+
+ 2/2
+ ---
+variables.c
+ - initialize_shell_variables: don't try to import function definitions
+ with invalid names from the environment if already in posix mode,
+ but create them as (invisible) exported variables so they pass
+ through the environment. Print an error message so user knows
+ what's wrong. Fixes bug reported by Tomas Trnka <ttrnka@mail.muni.cz>
+
+ 2/9
+ ---
+
+builtins/read.def
+ - sigalrm_seen, alrmbuf: now global so the rest of the shell (trap.c)
+ can use them
+ - sigalrm: just sets flag, no longer longjmps to alrmbuf; problem was
+ longjmp without manipulating signal mask, leaving SIGALRM blocked
+
+quit.h
+ - move CHECK_ALRM macro here from builtins/read.def so trap.c:
+ check_signals() can call it
+
+trap.c
+ - check_signals: add call to CHECK_ALRM before QUIT
+ - check_signals_and_traps: call check_signals() instead of including
+ CHECK_ALRM and QUIT inline. Integrating check for read builtin's
+ SIGALRM (where zread call to check_signals_and_traps can see it)
+ fixes problem reported by Mike Frysinger <vapier@gentoo.org>
+
+ 2/12
+ ----
+lib/glob/xmbsrtowcs.c
+ - xdupmbstowcs2: fixed but where end of string was not handled
+ correctly, causing loop to go past end of string in a bunch of cases.
+ Fixes bug reported by "Dashing" <dashing@hushmail.com>
+
+
+ 2/13
+ ----
+builtins/pushd.def
+ - popd_builtin: treat any argument that isn't -n or of the form
+ [-+][[:digit:]]* as an error. Fixes problem reported by Bruce
+ Korb <bruce.korb@gmail.com>
+
+ 2/14
+ ----
+configure.ac
+ - add check for sig_atomic_t; already a placeholder for it in
+ config.h.in
+
+ 2/15
+ ----
+subst.c
+ - do_compound_assignment: don't call assign_compound_array_list with
+ a NULL variable in case make_local_xxx_variable returns NULL
+ (it will if you try to shadow a readonly or noassign variable).
+ Fixes bug reported by Richard Tollerton <rich.tollerton@ni.com>
+
+ 2/16
+ ----
+variables.c
+ - make_local_variable: print error messager if an attempt is made to
+ create a local variable shadowing a `noassign' variable. Previously
+ we just silently refused to do it
+
+trap.[ch]
+ - get_original_signal: now global so rest of the shell can use it
+
+sig.c
+ - initialize_shell_signals: install a signal handler for SIGTERM
+ that does nothing except set a sigterm_received flag instead of
+ ignoring it with SIG_IGN, as long as SIGTERM is not ignored when
+ the shell is started. Use get_original_signal early to get the
+ original handler, since we will do that later anyway
+ - set_signal_handler: if installing sigterm_sighandler as the SIGTERM
+ handler, make sure to add SA_RESTART flag to make it as close to
+ SIG_IGN as possible
+
+sig.h
+ - sigterm_sighandler: new extern declaration
+
+quit.h
+ - RESET_SIGTERM: set sigterm_receved to 0
+ - CHECK_SIGTERM: check sigterm_received; if it's non-zero, treat it
+ as a fatal signal and call termsig_handler to exit the shell
+
+jobs.c
+ - make_child: call RESET_SIGTERM just before fork() so we can detect
+ if the child process received a SIGTERM before it's able to change
+ the signal handler back to what it was when the shell started
+ (presumably SIG_DFL). Only has effect if the shell installed
+ sigterm_sighandler for SIGTERM, interactive shells that were not
+ started with SIG_IGN as the SIGTERM handler
+ - make_child: call RESET_SIGTERM in the parent after fork() so the
+ rest of the shell won't react to it
+
+execute_cmd.c
+ - execute_simple_command: call CHECK_SIGTERM after make_child in child
+ to catch SIGTERM received after fork() and before restoring old
+ signal handlers
+ - execute_disk_command: call CHECK_SIGTERM after make_child in child
+ process after restoring old signal handlers and again just before
+ calling shell_execve. Fixes race condition observed by
+ Padraig Brady <p@draigbrady.com> when testing with his `timeout'
+ program
+
+lib/readline/display.c
+ - open_some_spaces: new function, subset of insert_some_chars that just
+ opens up a specified number of spaces to be overwritten
+ - insert_some_spaces: now just calls to open_some_spaces followed by
+ _rl_output_some_chars
+ - update_line: use col_temp instead of recalculating it using
+ _rl_col_width in the case where we use more columns with fewer bytes
+ - update_line: use open_some_spaces and then output the right number
+ of chars instead of trying to print new characters then overwrite
+ existing characters in two separate calls. This includes removing
+ some dodgy code and making things simpler. Fix from Egmont
+ Koblinger <egmont@gmail.com>
+ - use new variable `bytes_to_insert' instead of overloading temp in
+ some code blocks (nls - nfd, bytes that comprise the characters
+ different in the new line from the old)
+
+ 2/18
+ ----
+redir.c
+ - do_redirection_internal: add undoable redirection for the implicit
+ close performed by the <&n- and >&n- redirections. Fixes bug
+ reported by Stephane Chazelas <stephane.chazelas@gmail.com>
+
+ 2/19
+ ----
+sig.c
+ - termsig_handler: an interactive shell killed by SIGHUP and keeping
+ command history will try to save the shell history before exiting.
+ This is an attempt to preserve the save-history-when-the-terminal-
+ window-is-closed behavior
+
+ 2/21
+ ----
+braces.c
+ - brace_expand: if a sequence expansion fails (e.g. because the
+ integers overflow), treat that expansion as a simple string, including
+ the braces, and try to process any remainder of the string. The
+ remainder may include brace expansions. Derived from SuSE bug
+ 804551 example (https://bugzilla.novell.com/show_bug.cgi?id=804551)
+
+ 2/23
+ ----
+{quit,sig}.h,sig.c
+ - sigterm_received declaration now in sig.h; type is sig_atomic_t
+ - sigwinch_received type now sig_atomic_t
+ - sig.h includes bashtypes.h and <signal.h> if SIG_DFL not defined
+ (same logic as trap.h) to pick up sig_atomic_t
+
+unwind_prot.c
+ - include sig.h before quit.h (reverse order)
+
+ 2/27
+ ----
+builtins/shopt.def
+ - reset_shopt_options: make sure check_window_size is reset to the
+ default from config.h, not unconditionally to 0
+
+jobs.[ch]
+ - last_made_pid, last_asynchronous_pid: now volatile. Change from SuSE
+
+jobs.c
+ - wait_for: if we're using sigaction to install a handler for SIGCHLD,
+ make sure we specify SA_RESTART
+
+lib/{tilde,readline}/shell.c
+ - get_home_dir: instead of looking in the password file every time,
+ look once and cache the result
+
+sig.[ch]
+ - sigwinch_received, sigterm_received: now `volatile' qualified
+
+sig.c,quit.h
+ - interrupt_state,terminating_signal: now sig_atomic_t
+
+ 3/1
+ ---
+MANIFEST,examples/*
+ - removed around 120 files without FSF copyrights; requested by
+ Karl Berry in early January
+
+ 3/2
+ ---
+lib/malloc/malloc.c
+ - morecore: only check whether SIGCHLD is trapped if SIGCHLD is defined
+
+doc/bashref.texi
+ - Fixed most of the examples in the GNU Parallel section to use better
+ shell idioms following complaints on bug-bash; added a couple of
+ examples and smoothed out the text
+
+quit.h
+ - include "sig.h" for sig_atomic_t
+
+lib/readline/display.c
+ - update_line: when inserting one or more characters at the end of
+ the display line in a non-multibyte environment, just write from the
+ first difference to the end of the line and return. We don't have
+ to adjust _rl_last_c_pos. This is needed to adjust from the old
+ two-part copy to a single call to _rl_output_some_chars (change of
+ 2/16)
+
+ 3/4
+ ---
+Makefile.in,doc/Makefile.in
+ - PACKAGE_TARNAME, docdir: new variables substituted by autoconf
+ - OTHER_DOCS,OTHER_INSTALLED_DOCS: new variables with auxiliary
+ documentation files to be installed into $(docdir)
+ - install: add new rule to install $(OTHER_DOCS)
+ - uninstall: add new rule to uninstall $(docdir)/$(OTHER_INSTALLED_DOCS)
+
+doc/bash.1
+ - add URL to `POSIX' file in `SEE ALSO' section; put pointer to that
+ section in --posix and set -o posix descriptions
+
+examples/
+ - removed around 110 examples at the request of the FSF due to copyright
+ issues
+
+ 3/5
+ ---
+builtins/setattr.def
+ - readonly: modified help text slightly to make it clearer that
+ functions aren't changed or displayed unless the -f option is given.
+ Report from <gotmynick@gmail.com>
+
+ 3/9
+ ---
+include/typemax.h
+ - SIZE_MAX: define to 65535 (Posix minimum maximum) if not defined
+
+parse.y
+ - include "typemax.h" for possible SIZE_MAX definition, make sure we
+ include it after shell.h
+
+{braces,expr}.c
+ - include "typemax.h" for possible INTMAX_MIN and INTMAX_MAX definitions
+
+ 3/10
+ ----
+bashline.c
+ - bash_default_completion: make sure completion type of `!' (same as
+ TAB but with show-all-if-ambiguous set) and glob-word-completion
+ sets rl_filename_completion_desired to 0 so extra backslashes don't
+ get inserted by `quoting' the completion. We can't kill all the
+ matches because show-all-if-ambiguous needs them. Bug report from
+ Marcel (Felix) Giannelia <info@skeena.net>
+
+[bash-4.3-alpha frozen]
+
+ 3/14
+ ----
+general.c
+ - trim_pathname: use memmove instead of memcpy since the source and
+ destination pathnames may overlap. Report and fix from Matthew
+ Riley <mattdr@google.com>
+
+ 3/18
+ ----
+configure.ac
+ - socklen_t is defined as `unsigned int' if configure can't find it
+
+ 3/20
+ ----
+lib/readline/complete.c
+ - S_ISVTX: since it's not defined on all platforms (Minix), make sure
+ its use is protected with #ifdef
+
+ 3/21
+ ----
+doc/{bash.1,bashref.texi}
+ - Added mention of ${!name[@]} and ${!name[*]} expansions to get all
+ indices of an array. Suggested by Jonathan Leffler
+ <jonathan.leffler@gmail.com>
+
+ 3/24
+ ----
+subst.h
+ - SD_IGNOREQUOTE: new define for skip_to_delim; if set, means that
+ single quotes (for now) will be treated as ordinary characters
+
+subst.c
+ - skip_to_delim: handle SD_IGNOREQUOTE. no callers use it for now
+
+ 3/25
+ ----
+support/config.{guess,sub}
+ - updated to versions from autoconf-2.69
+
+ 3/31
+ ----
+lib/sh/shquote.c
+ - sh_single_quote: short-circuit quoting a single "'" instead of
+ creating a long string with empty single-quoted strings
+
+parser.h
+ - DOLBRACE_QUOTE2: new define, like DOLBRACE_QUOTE, but need to single-
+ quote results of $'...' expansion because quote removal will be
+ done later. Right now this is only done for ${word/pat/rep}
+
+parse.y
+ - parse_matched_pair: set state to DOLBRACE_QUOTE2 for pattern
+ substitution word expansion so we don't treat single quote specially
+ in the pattern or replacement string
+ - parse_matched_pair: if we're parsing a dollar-brace word expansion
+ (${...}) and we're not treating single quote specially within
+ double quotes, single-quote the translation of $'...' ansi-c
+ escaped strings. Original report and fix from Eduardo A.
+ Bustamante López <dualbus@gmail.com>
+
+subst.c
+ - extract_dollar_brace_string: ${word/pat/rep} scanning now sets the
+ DOLBRACE_QUOTE2 flag instead of DOLBRACE_QUOTE so we don't treat
+ single quotes specially within a double-quoted string
+
+execute_cmd.c
+ - fix_assignment_words: skip over assignment statements preceding a
+ command word before trying to figure out whether or not assignment
+ statements following a possible declaration command should be
+ treated specially. Fixes bug reported by Dan Douglas
+ <ormaaj@gmail.com>
+
+ 4/4
+ ---
+lib/readline/readline.c
+ - _rl_dispatch_subseq: only call _rl_vi_set_last (and check whether
+ the key is a text modification command) if the key sequence length
+ is 1. That keeps the arrow keys from setting the last command
+ when called in vi command mode. Fixes bug reported by Ian A.
+ Watson <watson_ian_a@lilly.com>
+
+ 4/6
+ ---
+lib/readline/bind.c
+ - rl_parse_and_bind: when parsing a double-quoted string as the value
+ of a variable, make sure we skip past the leading double quote.
+ Fix from Andreas Schwab <schwab@linux-m68k.org>
+
+variables.c
+ - hash_lookup: set new local variable last_table_searched to the table
+ a successful lookup appears in; tested in make_local_variable to
+ solve the problem below
+ - make_local_variable: if we find a variable with the tempenv flag
+ set at the same `level' as variable_context', but not found in the
+ temporary_env (temp environment preceding the builtin), return it.
+ The temp environment preceding the function call has already been
+ merged (in execute_function) into the list of variable contexts the
+ function sees as shell_variables by the time this is called. Fixes
+ inconsistency pointed out by Dan Douglas <ormaaj@gmail.com>
+
+subst.c
+ - expand_arith_string: expanded out contents of expand_string,
+ expand_string_internal, expand_string_if_necessary to create a
+ WORD_DESC and call call_expand_word_internal() on it directly.
+ We don't want process substitution to be performed ( 1<(2) ) should
+ mean something different in an arithmetic expression context.
+ It doesn't work to just turn on the DQUOTE flag, since that means
+ that things like ${x["expression"]} are not expanded correctly.
+ Fixes problem pointed out by Dan Douglas <ormaaj@gmail.com>
+
+ 4/13
+ ----
+subst.c
+ - process_substitute: run the EXIT trap before exiting, as other
+ shells seem to. Fixes problem pointed out by Dan Douglas
+ <ormaaj@gmail.com>
+
+lib/readline/readline.c
+ - readline_internal_setup: call rl_vi_insertion_mode to enter vi
+ mode instead of rl_vi_insert_mode to avoid resetting the saved last
+ command information. Posix says that `.' can repeat a command
+ that was entered on a previous line so we need to save the info.
+ Fixes bug reported by Ian A. Watson <watson_ian_a@lilly.com>
+
+ 4/14
+ ----
+lib/readline/complete.c
+ - rl_completion_matches: make sure xrealloc returns something non-null
+ (can happen when interrupted by a signal) before trying to add
+ matches to match_list
+
+subst.c
+ - array_remove_pattern: return NULL right away if array_variable_part
+ returns an invisible variable
+ - array_length_reference: handle array_variable_part returning an
+ invisible variable
+ - get_var_and_type: handle array_variable_part returning an invisible
+ variable
+
+ 4/15
+ ----
+execute_cmd.c
+ - execute_command_internal: make sure to run the EXIT trap for group
+ commands anywhere in pipelines, not just at the end. From a point
+ raised by Andreas Schwab <schwab@linux-m68k.org>
+
+variables.c
+ - bind_int_variable: make sure invisible flag is unset. Fixes problems
+ like "declare -ai a; : $(( a[4]=4 ));"
+
+arrayfunc.c
+ - array_variable_part: return variable even if invisible flag set,
+ callers must handle invisible vars
+
+ 4/18
+ ----
+builtins/set.def
+ - unset_builtin: if -n flag given, call unset_nameref instead of
+ unset_variable
+
+variables.c
+ - find_variable_nameref: print warning message if nameref circular
+ reference detected, return NULL and let caller deal with it
+
+builtins/declare.def
+ - declare_builtin: only disallow global references at this point if
+ we are at the global scope
+
+ 5/16
+ ----
+configure.ac
+ - update release status to beta
+
+ 5/23
+ ----
+trap.c
+ - run_pending_traps: save and restore pipeline around calls to
+ evalstring() in case we get a trap while running a trap. Have to
+ figure out the recursive running traps issue elsewhere. Fixes
+ bug reported by Roman Rakus <rrakus@redhat.com>
+ - run_pending_traps: make sure to set running_trap to the appropriate
+ signal value when running a trap command
+ - run_pending_traps: short-circuit immediately if running_trap set
+ when invoked. Could change this later to only skip if it would
+ run the same trap as currently being run (running_trap == sig + 1)
+
+configure.ac
+ - add warning if bison not found
+
+lib/readline/doc/rltech.texi
+ - new section with an example program illustrating the callback
+ interface. Suggested by Peng Yu <pengyu.ut@gmail.com>
+
+examples/loadables/Makefile.in
+ - remove references to `cut' and `getconf', which were removed in
+ early March
+
+ 5/28
+ ----
+lib/sh/pathphys.c
+ - sh_realpath: correct inverted two arguments to call to sh_makepath.
+ Report and fix from Julien Thomas <jthomas@exosec.fr>
+
+ 6/7
+ ---
+execute_cmd.c
+ - executing_line_number: the else clauses that are conditional on
+ various options being defined can simply be if clauses -- they are
+ mutually exclusive and all have `return' in the body. Fixes bug
+ reported by Flavio Medeiros <flaviomotamedeiros@gmail.com>
+
+ 6/25
+ ----
+lib/readline/readline.c
+ - readline_internal_setup: only sent the meta-key enable string to the
+ terminal if we've been told to use one and the terminal has been
+ successfully initialized (RL_ISSTATE (RL_STATE_TERMPREPPED) != 0).
+ Suggested by Dan Mick <dan.mick@inktank.com>
+
+lib/readline/signals.c
+ - _rl_signal_handler: call any defined signal hook after calling
+ rl_resize_terminal when handling a SIGWINCH. We already have called
+ the original SIGWINCH handler but will not be resending the signal
+ to ourselves
+
+ 6/27
+ ----
+lib/readline/doc/history.3, doc/bash.1
+ - fix description of the `$' modifier to note that it expands to the
+ last *word*, which is not always the last argument. Report from
+ ariyetz@gmail.com via gnu.org RT
+
+ 6/29
+ ----
+lib/glob/smatch.c
+ - glob_asciiranges: initialize to value of GLOBASCII_DEFAULT instead
+ of 0 (0 if not defined)
+
+configure.ac,config.h.in
+ - --enable-glob-asciiranges-default: new option, controls the value of
+ GLOBASCII_DEFAULT; use it to turn globasciiranges shopt option on
+ by default
+
+doc/bashref.texi
+ - document new --enable-glob-asciiranges-default configure option
+
+variables.c
+ - assign_in_env: implement += value appending semantics for assignments
+ preceding command names
+
+ 7/4
+ ---
+expr.c
+ - set lasttok = NUM in all of the functions that result in a number,
+ even if it's a boolean, to avoid errors with constructs like
+ 1 * x = 1, which should be an asignment error. Fixes problem
+ pointed out by Dan Douglas <ormaaj@gmail.com>
+
+parse.y
+ - decode_prompt_string: don't bother to call strcpy if
+ polite_directory_format returns its argument unchanged. It's not
+ necessary and Mac OS X 10.9 aborts because of a supposed overlapping
+ string copy. Bug and fix from simon@hitzemann.org
+
+subst.c
+ - parameter_brace_find_indir: new function, code from
+ parameter_brace_expand_indir that looks up the indirectly-referenced
+ variable, but does not expand it
+ - parameter_brace_expand_indir: call parameter_brace_find_indir to
+ look up indirected variable reference
+ - get_var_and_type: call parameter_brace_find_indir if it looks like we
+ are trying to manipulate an indirect variable reference like
+ ${!b%%foo}. This makes a difference if !b references an array
+ variable. Bug report from Dan Douglas <ormaaj@gmail.com>
+
+ 7/6
+ ---
+lib/sh/casemod.c
+ - sh_modcase: make sure argument passed to is_basic is <= UCHAR_MAX,
+ since cval can convert something to a wchar_t greater than UCHAR_MAX.
+ Fixes bug reported by Tomasz Tomasik <scx.mail@gmail.com>
+
+ 7/8
+ ---
+lib/readline/history.c
+ - add_history_time: if history_length == 0, referencing history_length
+ - 1 will result in an array bounds error, so make history_length be
+ at least 1 before going on. Fixes bug reported by Geng Sheng Liu
+ <gsliu.tju@gmail.com>
+
+builtins/setattr.def
+ - show_func_attributes: display definition (if NODEFS argument is 0) and
+ attributes for a particular function; used by `declare -fp name'
+
+builtins/declare.def
+ - declare_internal: call show_func_attributes if -f supplied with -p.
+ Fixes inconsistency observed by Linda Walsh <bash@tlinx.org>
+
+builtins/common.h
+ - new extern declaration for show_func_attributes
+
+builtins/read.def
+ - read_builtin: check the first supplied variable name for validity
+ before attempting to read any input, since we know we will have to
+ at least use that one. Don't check any other names yet. Suggested
+ by jidanni@jidanni.org
+
+ 7/10
+ ----
+redir.c
+ - do_redirection_internal: when closing a file descriptor with
+ r_close_this ([n]<&-) count close errors as redirection errors if
+ errno ends up as EIO or ENOSPC. Originally reported back in April
+ 2012 by Andrey Zaitsev <jstcdr@gmail.com>
+
+ 7/11
+ ----
+redir.c
+ - do_redirection_internal: before calling check_bash_input, make sure
+ that we don't call check_bash_input for an asynchronous process that
+ is replacing stdin with something else. The seek backwards affects
+ the parent process as well, since parents and children share the
+ file pointer. Fixes problem originally reported in March 2013 by
+ Martin Jackson <mjackson220.list@gmail.com>
+
+ 7/13
+ ----
+doc/{bash.1,bashref.texi}
+ - slight change to add a description of `shopt -o' suggested by Bruce
+ Korb <bruce.korb@gmail.com>
+
+ 7/19
+ ----
+lib/readline/histfile.c
+ - history_do_write: if close returns < 0, make sure we restore the
+ backup history file and return a non-zero value
+ - history_truncate_file: if write or close return < 0, make sure we
+ return a non-zero value
+
+[bash-4.3-beta frozen]
+
+ 7/21
+ ----
+lib/readline/isearch.c
+ - rl_display_search: now takes an entire search context flags word as
+ the second argument, instead of just reverse flag; changed callers
+ - rl_display_search: if the search has failed, add `failed ' to the
+ beginning of the search prompt
+ - _rl_isearch_dispatch: if the search has failed, display the entire
+ search string with an indication that the search failed but with the
+ last matching line. Suggested by jidanni@jidanni.org
+
+command.h
+ - W_ASSIGNINT: new word flag; used internally for make_internal_declare
+ and set by fix_assignment_words
+
+execute_cmd.c
+ - fix_assignment_words: set W_ASSIGNINT if compound assignment and -i
+ given as option. We don't do anything with the value yet
+
+subst.c
+ - shell_expand_word_list: rework the way the option list that is
+ passed to make_internal_declare is created
+
+ 8/1
+ ---
+doc/{bash.1,bashref.texi}
+ - minor changes to description of $! based on a report from Chris
+ Down <chris@chrisdown.name>
+
+arrayfunc.c
+ - assign_array_element_internal: before trying to get an array's max
+ index to process a negative subscript, make sure the array exists.
+ Bug report from Geir Hauge <geir.hauge@gmail.com>
+
+ 8/2
+ ---
+arrayfunc.c
+ - assign_array_element_internal: before using array_max_index() when
+ processing a negative subscript, make sure the variable is an array.
+ if it's not, use 0 as array_max_index assuming it's a string.
+ Fixes bug report from Geir Hauge <geir.hauge@gmail.com>
+
+ 8/3
+ ---
+Makefile.in
+ - pcomplete.o: add dependency on $(DEFDIR)/builtext.h. Suggested by
+ Curtis Doty <curtis@greenkey.net>
+
+ 8/5
+ ---
+lib/glob/sm_loop.c
+ - strcompare: short-circuit and return FNM_NOMATCH if the lengths of the
+ pattern and string (pe - p and se - s, respectively) are not equal
+ - strcompare: don't bother trying to set *pe or *se to '\0' if that's
+ what they already are. Fixes bug reported by Geir Hauge
+ <geir.hauge@gmail.com>
+
+ 8/6
+ ---
+doc/{bash.1,bashref.texi},builtins/hash.def,lib/readline/doc/rluser.texi
+ - minor typo changes from Geir Hauge <geir.hauge@gmail.com>
+
+bultins/help.def
+ - show_longdoc: avoid trying to translate the empty string because it
+ often translates to some boilerplate about the project and
+ translation. Report and fix from Geir Hauge <geir.hauge@gmail.com>
+
+ 8/8
+ ---
+builtins/help.def
+ - help_builtin: try two passes through the list of help topics for each
+ argument: one doing exact string matching and one, if the first pass
+ fails to find a match, doing string prefix matching like previous
+ versions. This prevents `help read' from matching both `read' and
+ `readonly', but allows `help r' to match everything beginning with
+ `r'. Inspired by report from Geir Hauge <geir.hauge@gmail.com>
+
+ 8/13
+ ----
+builtins/fc.def
+ - fc_builtin,fc_gethnum: calculate `real' end of the history list and
+ use it if -0 is specified as the beginning or end of the history
+ range to list. Doesn't work for fc -e or fc -s by design. Feature
+ requested by Mike Fied <micfied@gmail.com>
+
+ 8/16
+ ----
+trap.c
+ - _run_trap_internal: use {save,restore}_parser_state instead of
+ {save,restore}_token_state. It's more comprehensive
+
+ 8/23
+ ----
+doc/bash.1
+ - disown: remove repeated text. Report and fix from Thomas Hood
+ <jdthood@gmail.com>
+
+ 8/25
+ ----
+lib/readline/rltty.c
+ - set_special_char: fix prototype (last arg is rl_command_func_t *)
+
+sig.c
+ - set_signal_handler: return oact.sa_handler only if sigaction
+ succeeds; if it doesn't, return SIG_DFL (reasonable default). From
+ https://bugzilla.redhat.com/show_bug.cgi?id=911404
+
+bashline.c
+ - attempt_shell_completion: fix to skip assignment statements preceding
+ command name even if there are no programmable completions defined.
+ From https://bugzilla.redhat.com/show_bug.cgi?id=994659
+ - attempt_shell_completion: if still completing command word following
+ assignment statements, do command completion even if programmable
+ completion defined for partial command name entered so far
+
+ 8/26
+ ----
+pcomplete.c
+ - pcomp_filename_completion_function: make sure rl_filename_dequoting_function
+ is non-NULL before trying to call it. Bug and fix from
+ Andreas Schwab <schwab@linux-m68k.org>
+
+bashline.c
+ - bash_command_name_stat_hook: if *name is not something we're going
+ to look up in $PATH (absolute_program(*name) != 0), just call the
+ usual bash_filename_stat_hook and return those results. This makes
+ completions like $PWD/exam[TAB] add a trailing slash
+
+ 9/2
+ ---
+builtins/read.def
+ - read_builtin: before comparing what we read to the delim, make sure
+ we are not supposed to be ignoring the delimiter (read -N). We
+ set the delim to -1, but it's possible to read a character whose
+ int value ends up being between -1 and -128. Fixes bug
+ reported by Stephane Chazelas <stephane.chazelas@gmail.com>
+
+doc/{bash.1,bashref.texi}
+ - word splitting: crib some language from Posix to make it clear that
+ characters in IFS are treated as field *terminators*, not field
+ *separators*. Addresses issue raised by DJ Mills
+ <danielmills1@gmail.com>
+
+lib/readline/{util.c,rldefs.h}
+ - _rl_stricmp,_rl_strnicmp: now take const char * string arguments;
+ changed prototype declarations
+
+ 9/5
+ ---
+doc/{bash.1,bashref.texi}
+ - [[: modify description of pattern matching to make it clear that the
+ match is performed as if the extglob option were enabled. From Red
+ Hat bug https://bugzilla.redhat.com/show_bug.cgi?id=1002078
+
+ 9/12
+ ----
+lib/readline/isearch.c
+ - _rl_isearch_dispatch: if we read an ESC and it's supposed to
+ terminate the search, make sure we check for typeahead with
+ _rl_pushed_input_available, since installing a hook function causes
+ typeahead to be collected in `ibuffer' (input.c). If there is any,
+ make sure we still use the ESC as a prefix character. Bug and fix
+ from Mike Miller <mtmiller@ieee.org>
+
+ 9/16
+ ----
+builtins/{caller,cd,kill,pushd,wait}.def
+ - builtin_usage(): make sure call to this sets return status to
+ EX_USAGE
+
+ 9/18
+ ----
+terminal.c
+ - rl_change_environment: new application-settable variable; if non-
+ zero (the default), readline will modify LINES and COLUMNS in the
+ environment when it handles SIGWINCH
+ - _rl_get_screen_size: if rl_change_environment is non-zero, use setenv
+ to modify LINES and COLUMNS environment variables
+
+readline.h
+ - rl_change_environment: new extern declaration for applications
+
+ 9/22
+ ----
+configure.ac
+ - relstatus: bumped version to bash-4.3-beta2
+
+ 9/24
+ ----
+
+lib/readline/readline.c
+ - bind_arrow_keys_internal: added more key bindings for the numeric key
+ pad arrow keys on mingw32. Patch from Pierre Muller
+ <pierre.muller@ics-cnrs.unistra.fr>
+
+ 10/19
+ -----
+
+bashline.c
+ - maybe_restore_tilde: version of restore_tilde that honors `direxpand';
+ calls restore_tilde after saving directory expansion hook if
+ necessary. Report from Andreas Schwab <schwab@linux-m68k.org>
+
+builtins/cd.def
+ - -@: new option, allows cd to use `extended attributes' present in
+ NFSv4, ZFS; idea taken from ksh93. Attributes associated with a
+ file are presented as a directory containing the attributes as
+ individual files. Original patch contributed by Cedric Blancher
+ <cedric.blancher@gmail.com>
+
+ 10/20
+ -----
+aclocal.m4
+ - BASH_CHECK_MULTIBYTE: check for wcwidth being broken with unicode
+ combining characters needs a value to use when cross-compiling.
+ Bug report from Bert Sutherland <bertsutherland@gmail.com>
+
+doc/{bash.1,bashref.texi}
+ - document new -@ option to cd builtin
+
+ 10/28
+ -----
+lib/glob/{{gmisc,glob}.c,glob.h}
+ - extglob_pattern renamed to extglob_pattern_p, declared in glob.h
+
+subst.c
+ - expand_word_internal: typo fix: case to fix " $@\ " bug in bash-4.2
+ had a typo (& isexp instead of &&)
+
+ 10/29
+ -----
+input.c
+ - getc_with_restart: make sure local_index and local_bufused are
+ reset to 0 before returning EOF, in case we are running an interactive
+ shell without line editing and ignoreeof is set. Report and fix
+ from Yong Zhang <yong.zhang@windriver.com>
+
+lib/readline/search.c
+ - _rl_nsearch_init: take out extra third argument to rl_message; it
+ only matches prototype (and maybe format) in cases where
+ PREFER_STDARG and USE_VARARGS are both undefined, which is rare
+
+ 10/31
+ -----
+subst.c
+ - process_substitute: when opening the named pipe in the child, open
+ without O_NONBLOCK to avoid race conditions. Happens often on AIX.
+ Bug report and fix from Michael Haubenwallner
+ <michael.haubenwallner@salomon.at>
+
+builtins/ulimit.def
+ - RLIMIT_NTHR: if RLIMIT_PTHREAD is not defined, but RLIMIT_NTHR is,
+ use RLIMIT_NTHR (NetBSD)
+
+ 11/5
+ ----
+locale.c
+ - set_default_locale_vars,set_locale_var: if TEXTDOMAINDIR has been
+ set, and default_dir has a non-null value, call bindtextdomain(3)
+ when TEXTDOMAIN is assigned a value. Fixes problem reported by
+ Michael Arlt <qwertologe@googlemail.com>
+
+ 11/6
+ ----
+builtins/cd.def
+ - cdxattr: only create synthetic pathname in `buf' if NDIRP argument
+ is non-null
+ - change_to_directory: if we have specified -@ and cdxattr returns
+ failure, fail immediately. Fixes bug reported by Joshuah Hurst
+ <joshhurst@gmail.com>
+
+ 11/12
+ -----
+redir.c
+ - print_redirection: change r_err_and_out (&>) and its append form,
+ r_append_err_and_out (&>>) cases to separate redirection operator
+ from filename by a space, in case we have a process substitution.
+ Fixes bug reported by admn ombres <admn.ombres@gmail.com>
+
+ 11/15
+ -----
+execute_cmd.c
+ - execute_simple_command: don't close process substitution fds until
+ we are finished executing any current shell function. Partial fix
+ for bug reported by John Dawson <john.dawson@gmail.com>
+
+support/shobj-conf
+ - add support for Darwin 13 (Mac OS X 10.9, Mavericks). Based on a
+ report by Ludwig Schwardt <ludwig.schwardt@gmail.com>
+
+ 11/20
+ -----
+[bash-4.3-rc1 frozen]
+
+ 11/24
+ -----
+builtins/printf.def
+ - bind_printf_variable: make sure that the variable assigned to is
+ no longer marked as invisible. Fixes bug reported by NBaH
+ <nbah@sfr.fr>
+
+ 11/28
+ -----
+jobs.c
+ - delete_old_job: fix off-by-one error in job index in call to
+ internal_warning. Bug report from Peter Cordes <peter@cordes.ca>
+
+ 11/30
+ -----
+doc/bashref.texi
+ - add string to description of special parameters with name of
+ special parameter prefixed by a $, so you can search for $#,
+ for instance
+
+ 12/2
+ ----
+lib/readline/{histexpand.c
+ - get_history_event: account for current_history() possibly returning
+ NULL. Report and fix from Pankaj Sharma <pankaj.s01@samsung.com>
+
+
+ 12/11
+ -----
+
+lib/readline/parse-colors.c
+ - get_funky_string: don't call abort if we see something we can't
+ parse; just return an error
+ - _rl_parse_colors: if we encounter an error while parsing $LS_COLORS
+ we need to leave _rl_color_ext_list as NULL after freeing its
+ elements, then turn off _rl_colored_stats. Report and fix from Martin
+ Wesdorp <mwesdorp@casema.nl>
+
+ 12/13
+ -----
+
+lib/readline/parse-colors.c
+ - _rl_parse_colors: if we encounter an unrecognized prefix, throw an
+ error but try to recover and go on to the next specification
+
+variables.c
+ - make_local_variable: for new variables this function creates, set
+ the att_invisible attribute. All callers from declare_internal.
+ Indirectly, this is a fix for bug with `declare -n var; var=foo;'
+ reported by Pierre Gaston <pierre.gaston@gmail.com>
+ - bind_variable: if assigning to nameref variable that doesn't have
+ a value yet (e.g., with `declare -n var; var=foo'), don't try to
+ use the unset name. Fixes a segfault reported by Pierre Gaston
+ <pierre.gaston@gmail.com>
+
+execute_cmd.c
+ - execute_command_internal: make sure last_command_exit_value is set
+ to 0 after any command executed in the background. Fixes bug
+ reported by Martin Kealey <martin@kurahaupo.gen.nz>
+
+ 12/17
+ -----
+support/config.{guess,sub}
+ - updated to latest versions from git
+
+ 12/19
+ -----
+parse.y
+ - struct STRING_SAVER: now has a new `flags' element, to identify the
+ caller: alias expansion, double-paren parsing, or parse_and_execute
+ - push_string: now sets flags to PSH_ALIAS if `ap' argument is non-NULL
+ - push_string: now doesn't attempt to call strlen on a NULL string to
+ set shell_input_line_size
+ - parser_expanding_alias, parser_save_alias, parser_restore_alias: new
+ functions to provide an external interface to push_string and
+ pop_string; parser_save_alias sets flags element to PSH_SOURCE (could
+ be renamed PSH_EXTERN someday)
+ - shell_getc: when yy_getc returns '\0', instead of just testing
+ whether the pushed_string_list is not-empty before popping it, don't
+ pop if if the saved string has flags PSH_SOURCE, indicating that
+ parse_and_execute set it before setting bash_input to the string.
+ We should continue reading to the end of that string before popping
+ back to a potential alias. Partial solution for the problem of aliases
+ with embedded newlines containing `.' commands being executed out of
+ order reported by Andrew Martin <andrew.martin@gmail.com>
+ - shell_getc: when yy_getc returns '\0' and there is a saved string of
+ type PSH_SOURCE, restart the read without popping the string stack
+ if we have not read to the end of bash_input.location.string. Rest
+ of fix for out-of-order execution problem
+
+externs.h
+ - parser_expanding_alias, parser_save_alias, parser_restore_alias: new
+ extern function declarations
+
+builtins/evalstring.c
+ - pe_prologue: if the parser is expanding an alias, make sure to add
+ an unwind-protect to restore the alias; undoes the work that will be
+ performed by parse_and_execute/parse_string
+ - parse_and_execute,parse_string: after calling push_stream to save
+ bash_input, check whether or not the parser is currently expanding
+ an alias (parser_expanding_alias() != 0). If it is, we want to save
+ that string in the pushed_string_list, which we do with
+ parser_save_alias.
+
+ 12/23
+ -----
+execute_cmd.c
+ - execute_for_command: make sure to set line_number before expanding
+ the word list, so expansion errors have the right line number.
+ From a report from Ben Okopnik <ben@okopnik.com>
+
+expr.c
+ - exp2: save token pointer before calling readtok(), arrange to use
+ saved token pointer when printing error token on a division by 0
+ error
+
+ 12/27
+ -----
+lib/readline/display.c
+ - rl_redisplay: when calculating effects of invisible characters in a
+ prompt that is split across physical screen lines to set the indices
+ of linebreaks, don't bother testing local_prompt_prefix (line 751).
+ That prefix doesn't matter when calculating prompt visible and
+ invisible characters. Fixes problem reported by Jinesh Choksi
+ <jinesh@onelittlehope.com>
+
+Makefile.in
+ - install: make sure to use $(DESTDIR) when installing OTHER_DOCS.
+ Report and fix from Matthias Klose <doko@debian.org>
+
+doc/texinfo.tex
+ - updated to version of 2013-09-11
+
+ 12/28
+ -----
+lib/readline/undo.c
+ - rl_do_undo: if we are undoing from a history entry (rl_undo_list ==
+ current_history()->data), make sure the change to rl_line_buffer is
+ reflected in the history entry. We use the guts of
+ rl_maybe_replace_line to do the work. Fixes problem reported by
+ gregrwm <backuppc-users@whitleymott.net>
+
+ 12/30
+ -----
+sig.c
+ - sigint_sighandler: if we get a SIGINT (and this signal handler is
+ installed) while the wait builtin is running, note that we received
+ it in the same way as jobs.c:wait_sigint_handler and return. The
+ various wait_for functions will look for that with CHECK_WAIT_INTR.
+ This fixes the wait builtin not being interruptible in an interactive
+ job control shell
+
+ 12/31
+ -----
+trap.c
+ - set_signal_hard_ignored: rename set_signal_ignored to this, since it
+ both sets original_signals[sig] and sets the HARD_IGNORE flag
+ - set_signal_ignored: new function, now just sets original_signals[sig]
+
+trap.h
+ - set_signal_hard_ignored: new external declaration
+
+sig.c
+ - initialize_terminating_signals: call set_signal_hard_ignored instead
+ of set_signal_ignored for signals with disposition SIG_IGN when the
+ shell starts
+
+execute_cmd.c
+ - setup_async_signals: make sure we get the original dispositions for
+ SIGINT and SIGQUIT before starting the subshell, and don't call
+ set_signal_ignored because that sets original_signals[sig]. If we
+ don't, subsequent attempts to reset handling using trap will fail
+ because it thinks the original dispositions were SIG_IGN. Posix
+ interpretation 751 (http://austingroupbugs.net/view.php?id=751)
+
+ 1/2/2014
+ --------
+lib/sh/stringvec.c
+ - strvec_mcreate, strvec_mresize: versions of create and resize that
+ use malloc and realloc, respectively, instead of xmalloc/xrealloc
+
+braces.c
+ - expand_amble,mkseq: use strvec_mcreate/strvec_mresize so we can
+ catch and handle memory allocation failures instead of aborting
+ with the xmalloc/xrealloc interface
+
+lib/sh/strdup.c
+ - strdup replacement function for ancient systems that don't have it
+
+lib/sh/itos.c
+ - mitos: new function, itos that uses strdup instead of savestring
+
+externs.h
+ - strvec_mcreate/strvec_mresize: new extern declarations
+ - mitos: new extern declaration
+
+configure.ac
+ - bash version moved to 4.3-rc2
+
+ 1/6
+ ---
+doc/bash.1,lib/readline/doc/{rluser.texi,readline.3}
+ - separate the description of what happens when readline reads the
+ tty EOF character from the description of delete-char, leaving a
+ note in the delete-char description about common binding for ^D.
+ From suggestion by Parke <parke.nexus@gmail.com>
+
+lib/readline/doc/{version.texi,history.3,*.texi}
+ - updated email addresses and copyright dates
+
+ 1/7
+ ---
+variables.c
+ - delete_var: new function, just removes a variable from a hash table
+ and frees it, without doing anything else
+ - make_variable_value: if we are trying to assign to a nameref variable,
+ return NULL if the value is null or the empty string or not a valid
+ identifier
+
+variables.h
+ - delete_var: new extern declaration
+
+subst.h
+ - ASS_NAMEREF: new define for assignments, means assigning to a nameref
+ variable
+
+builtins/declare.def
+ - declare_internal: if we are creating and assigning to a nameref
+ variable, make sure the value is a valid variable name (checks done
+ by make_variable_value via bind_variable_value) and display an
+ error message, deleting the variable we just created, if it is not.
+ Fixes bug reported by Peggy Russell <prusselltechgroup@gmail.com>
+
+ 1/9
+ ---
+builtins/declare.def
+ - declare_internal: turning on nameref attribute for an existing
+ variable turns off -i/-l/-u/-c attributes (essentially the ones
+ that cause evaluation at assignment time) for ksh93 compat
+
+builtins/setattr.def
+ - show_name_attributes: if asked to display attributes and values for
+ a nameref variable, don't follow the nameref chain to the end. More
+ ksh93 compat
+
+ 1/10
+ ----
+trap.c
+ - _run_trap_internal: use {save,restore}_parser_state instead of
+ {save,restore}_token_state, like in run_pending_traps(); don't
+ need to save and restore last_command_exit_value as a result
+ - _run_trap_internal: call {save,restore}_pipeline like in
+ run_pending_traps()
+ - run_pending_traps: since we no longer run traps in a signal handler
+ context, do not block and unblock the trapped signal while the
+ trap is executing
+ - run_pending_traps: allow recursive invocations (basically, running
+ traps from a trap handler) with only a warning if the shell is
+ compiled in debug mode. If a caller doesn't want this to happen,
+ it should test running_trap > 0. signal_in_progress (sig) only works
+ for the signals the shell handles specially
+
+bashline.c
+ - bash_event_hook: make sure we clean up readline if interrupt_state
+ is set, not only when SIGINT is not trapped. check_signals_and_traps
+ will call check_signals, which calls QUIT, which will longjmp back
+ to top_level, running the interrupt trap along the way. Fixes the
+ problem of signal handlers being reset out from under readline, and
+ not being set properly the next time readline is called, because
+ signals_set_flag is still set to 1. XXX - might need to do this
+ for other signals too?
+
+ 1/11
+ ----
+subst.h
+ - SD_GLOB: new define for skip_to_delim; means we are scanning a
+ glob pattern.
+
+subst.c
+ - skip_to_delim: if flags include SD_GLOB, assume we are scanning a
+ glob pattern. Currently only used to skip bracket expressions
+ which may contain one of the delimiters
+
+ 1/12
+ ----
+subst.c
+ - parameter_brace_expand: when expanding $@ as part of substring
+ expansion, pattern substitution, or case modification, don't turn
+ on the QUOTED_NULL flag. The code that constructs the word to be
+ returned from expand_word_internal expects a different code path
+ when $@ is being expanded. Fixes bug reported by Theodoros
+ V. Kalamatianos <thkala@gmail.com>
+
+ 1/19
+ ----
+subst.c
+ - list_dequote_escapes: new function; analogue of list_quote_escapes
+
+pathexp.c
+ - quote_string_for_globbing: fix case where unescaped ^A is last char
+ in string; need to pass it through unaltered instead of turning it
+ into a bare backslash
+ - quote_string_for_globbing: when quoting for regexp matching in [[,
+ don't treat backslash as a quote character; quote the backslash as
+ any other character. Part of investigation into reports from
+ Eduardo A. Bustamante López <dualbus@gmail.com>
+
+ 1/25
+ ----
+builtins/gen-helpfiles.c
+ - write_helpfiles: add prototype
+ - make sure to #undef xmalloc/xfree/xrealloc/free if USING_BASH_MALLOC
+ is defined. the code does not use them, and we don't link against
+ xmalloc.o. Report from Linda Walsh <bash@tlinx.org>
+
+Makefile.in
+ - variables.o: add dependency on builtins/builtext.h; helps with
+ parallel builds. Report from Linda Walsh <bash@tlinx.org>
+
+support/shobj-conf
+ - darwin: combine the stanzas into one that will not require them to
+ be updated on each Mac OS X release. Report and fix from Max Horn
+ <max@quendi.de>
+
+ 1/27
+ ----
+support/shobj-conf
+ - darwin: changed the install_name embedded into the shared library
+ to contain only the major version number, not the minor one. The
+ idea is that the minor versions should all be API/ABI compatible,
+ and it is better to link automatically with the latest one. Idea
+ from Max Horn <max@quendi.de>
+
+ 1/29
+ ----
+[bash-4.3-rc2 released]
+
+ 1/30
+ ----
+lib/readline/readline.h
+ - rl_clear_history, rl_free_keymap: add extern declarations. Report
+ from Hiroo Hayashi <hiroo.hayashi@computer.org>
+
+general.c
+ - include trap.h for any_signals_trapped() prototype
+
+lib/sh/unicode.c
+ - include <stdio.h> for sprintf prototype
+
+ 1/31
+ ----
+execute_cmd.c
+ - execute_simple_command: only posix-mode shells should exit on an
+ assignment failure in the temporary environment preceding a special
+ builtin. This is what the documentation and code comments have
+ always said
+ - execute_simple_command: make sure redirection errors, word expansion
+ errors, and assignment errors to Posix special builtins cause a
+ non-interactive posix mode shell to exit. Previously the shell
+ would not exit if the failed special builtin was on the LHS of ||
+ or &&
+
+pathexp.c
+ - quote_string_for_globbing: when quoting a regular expression
+ (QGLOB_REGEXP), allow an unquoted backslash to pass through
+ unaltered. Don't use it as a quote character or quote it. More
+ investigation from 1/24 and report by Mike Frysinger
+ <vapier@gentoo.org>
+ - quote_string_for_globbing: when quoting a regular expression
+ (QGLOB_REGEXP), turn CTLESC CTLESC into CTLESC without adding a
+ backslash to quote it. We should not have to quote it because it is
+ not a character special to EREs. More investigation from 1/24
+
+lib/glob/glob.c
+ - glob_testdir: now takes a second flags argument (currently unused);
+ changed prototype and callers
+
+ 2/1
+ ---
+lib/glob/glob.c
+ - glob_testdir: if flags argument includes GX_ALLDIRS (globstar), use
+ lstat so we skip symlinks when traversing the directory tree.
+ Originally reported by Chris Down <chris@chrisdown.name>
+
+ 2/2
+ ---
+lib/readline/undo.c
+ - rl_do_undo: make sure CUR is non-zero before dereferencing it to
+ check cur->data against rl_undo_list. Report and fix from
+ Andreas Schwab <schwab@linux-m68k.org>
+
+doc/{bash.1,bashref.texi}
+ - added slight clarifying language to the description of $*,
+ describing what happens when the expansion is not within double
+ quotes
+
+ 2/4
+ ---
+test.c
+ - unary_test: add code to -v case so that it interprets `bare' array
+ references (foo[1]) and returns true if that index has a value
+
+ 2/5
+ ---
+trap.c
+ - restore_default_signal: fix SIGCHLD special case for SIG_TRAPPED flag
+ off but SIG_INPROGRESS mode set and handler IMPOSSIBLE_TRAP_HANDLER;
+ continue with resetting handler in this case. maybe_set_sigchld_trap
+ will check these things before resetting sigchld trap from
+ run_sigchld_trap. Fixes (apparently long-standing?) problem reported
+ by Alexandru Damian <alexandru.damian@intel.com>
+
+ 2/6
+ ---
+lib/sh/strtrans.c
+ - ansic_quote: fixed a bug when copying a printable character that
+ consumes more than one byte; byte counter was not being incremented.
+ Bug report from jidanni@jidanni.org
+
+ 2/7
+ ---
+input.c
+ - getc_with_restart: if read(2) returns -1/EINTR and interrupt_state or
+ terminating_signal is set (which means QUIT; will longjmp out of this
+ function), make sure the local buffer variables are zeroed out to
+ avoid reading past the end of the buffer on the next call. Bug report
+ from Dan Jacobson <jidanni@jidanni.org>
+
+ 2/9
+ ---
+bashline.c
+ - command_word_completion_function: if a directory in $PATH contains
+ quote characters, we need to quote them before passing the candidate
+ path to rl_filename_completion_function, which performs dequoting on
+ the pathname it's passed. Fixes bug reported by Ilyushkin Nikita
+ <ilyushkeane@gmail.com>
+
+ 2/11
+ ----
+parse.y
+ - xparse_dolparen: save and restore shell_eof_token around call to
+ parse_string, intead of just leaving it set to ')'
+ - shell_getc: when -v is set, only print the command line when
+ shell_eof_token is 0, so we don't print it multiple times when
+ recursively entering the parser to parse $(...) commands. Fixes
+ bug reported by Greg Wooledge <wooledg@eeg.ccf.org>
+
+[changed release status to 4.3-release]
+
+ 2/13
+ ----
+lib/sh/strtrans.c
+ - ansic_quote: handle case where mbrtowc reports that the multibyte
+ sequence is incomplete or invalid. Fixes bug reported by
+ Eduardo A. Bustamante López <dualbus@gmail.com>
+
+ 2/14
+ ----
+variables.c
+ - find_variable_nameref_context: fix a problem that caused the loop
+ to go one context too close to the global context. In some cases,
+ simple variable assignment would set a variable in the global
+ context instead of a local context. Bug report from
+ Geir Hauge <geir.hauge@gmail.com>
+
+ 2/26
+ ----
+[bash-4.3 released]
+
+ 2/27
+ ----
+aclocal.m4
+ - broken wcwidth check: fix typo reported by David Michael
+ <fedora.dm0@gmail.com>
+
+ 2/28
+ ----
+support/bashbug.sh
+ - add ${BUGADDR} to error message printed if sending mail fails
+
+trap.c
+ - _run_trap_internal: don't call {save,restore}_pipeline if running
+ DEBUG trap; run_debug_trap calls them itself. Fixes bug reported
+ by Moe Tunes <moetunes42@gmail.com>
+
+test.c
+ - unary_test: fix 'R' case by using find_variable_noref instead of
+ find_variable
+ - test_unop: add back missing 'R' case. Fixes bug reported by
+ NBaH <nbah@sfr.fr>
+
+ 3/2
+ ---
+jobs.c
+ - end_job_control: if job control is active, we changed the terminal's
+ process group, so make sure we restore it. Fixes bug reported by
+ Eduardo A. Bustamante López <dualbus@gmail.com>
+
+ 3/7
+ ---
+pcomplete.c
+ - pcomp_curtxt: new variable, holds the original text to be completed
+ as passed to the programmable completion code
+ - pcomp_filename_completion_function: if we are running compgen
+ (presumably in a shell function completion) and performing readline
+ completion, check the word being completed. If it's not empty, but
+ the original word passed to the programmable completion code is an
+ empty string (""), call a dequoting function if one is available.
+ This compensates for an assumption in bash-completion. Reported by
+ Albert Shih <Albert.Shih@obspm.fr>
+
+lib/readline/readline.c
+ - _rl_dispatch_subseq: when deciding whether or not to set vi mode's
+ idea of the last command, use whether or not the dispatching keymap
+ is vi_movement_keymap instead of the key sequence length. The `c',
+ `d', and `y' commands all take motion commands as `arguments' and
+ will produce key sequences longer than 1 character. The arrow keys
+ will end up dispatching out of a different keymap, so the test will
+ prevent arrow keys from setting the last command (the problem in
+ bash-4.2). Bug report from Daan van Rossum <daan@flash.uchicago.edu>
+
+lib/readline/vi_mode.c
+ - _rl_vi_motion_command: convenience function to test whether a key is
+ a vi-mode motion command
+
+lib/readline/rlprivate.h
+ - _rl_vi_motion_command: extern declaration
+
+parse.y
+ - parse_matched_pair: we should not skip processing single quotes in
+ posix mode if dolbrace_state == DOLBRACE_QUOTE2 (pattern
+ substitution). Fixes bug reported by David Sines
+ <dave.gma@googlemail.com>
+
+ 3/10
+ ----
+lib/readline/readline.c
+ - _rl_dispatch_callback: treat a return value of -1 as the end of
+ a command dispatch sequence if the current context doesn't
+ indicate that we're reading a multi-key sequence
+ ((cxt->flags & KSEQ_SUBSEQ) == 0). Turn off the multikey flag
+ and free the context chain in this case. Fixes one bug reported
+ by Felix Yan <felixonmars@gmail.com> to bug-readline list
+ - _rl_dispatch_callback: treat a return value of > 0 the same as 0
+ and return from the function, since only values < 0 cause us to
+ simulate recursion. Rest of fix for bug tracked down by
+ Anatol Pomozov <anatol.pomozov@gmail.com>
+
+ 3/11
+ ----
+
+execute_cmd.c
+ - execute_in_subshell: if a longjmp occurs, set result to
+ EXECUTION_FAILURE only if last_command_exit_value == EXECUTION_SUCCESS;
+ use value of last_command_exit_value otherwise. Fixes cosmetic
+ issue reported by Dennis Lambe Jr. <malsyned@malsyned.net>
+
+doc/bash.1
+ - shell-kill-word and shell-backward-kill-word should be documented
+ as unbound by default. Report from Oliver Hartley
+ <ohartley@talktalk.net>
+
+trap.c
+ - run_pending_traps: save value of $? before running trap commands in
+ trap_saved_exit_value, like run_exit_trap
+ - _run_trap_internal: save value of $? before running trap commands in
+ trap_saved_exit_value, like run_exit_trap
+
+builtins/common.c
+ - get_exitstat: when running `return' in a trap action, and it is not
+ supplied an argument, use the saved exit status in
+ trap_saved_exit_value. Fixes Posix problem reported by
+ Eduardo A. Bustamante López <dualbus@gmail.com>
+
+ 3/13
+ ----
+lib/sh/shquote.c
+ - sh_contains_quotes: new function, returns true if a given string
+ contains any of the shell quote characters (single quote, double
+ quote, or backslash)
+
+externs.h
+ - sh_contains_quotes: new extern declaration
+
+pcomplete.c
+ - pcomp_filename_completion_function: more changes for the benefit of
+ bash-completion: if the argument is not the same as the original
+ argument passed to the programmable completion code (pcomp_curtxt),
+ and we are being run by compgen as part of a completion, dequote the
+ argument as bash-completion expects. Fix for the complete-word-
+ with-quoted-special-chars problem with bash-completion
+
+ 3/17
+ ----
+execute_cmd.c
+ - execute_intern_function: when in posix mode, make defining a function
+ with the same name as a special builtin a fatal error only when the
+ shell is not interactive. Interactive shells display an error
+ message and go on. From a discussion with Doug McIlroy
+ <doug@cs.dartmouth.edu>
+
+ 3/18
+ ----
+arrayfunc.c
+ - assign_compound_array_list: when using expand_assignment_string_to_string
+ to expand the value in a ( [x]=y ) compound assignment, make sure
+ that we convert 0x0 to "" when expanding [x]= so it doesn't appear as
+ if the index is unset. Fixes bug reported by Geir Hauge
+ <geir.hauge@gmail.com>
+
+builtins/common.c
+ - get_exitstat: update fix of 3/11 to allow the DEBUG trap to use the
+ current value of $? instead of the value it had before the trap
+ action was run. This is one reason the DEBUG trap exists, and
+ extended debug mode uses it. Might want to do this only in Posix
+ mode
+
+doc/{bash.1,bashref.texi}
+ - return: add language cribbed from Posix saying what happens when
+ return is run without an argument from a trap, including the DEBUG
+ trap exception
+
+ 3/19
+ ----
+lib/glob/gmisc.c
+ - extglob_pattern_p: make sure ?(patlist) is flagged as an extglob
+ pattern
+
+lib/glob/glob.c
+ - extglob_skipname: rewrite to handle patterns that begin but do not
+ end with an extglob pattern; change test for easy case and loop
+ through patterns accordingly. Fixes problem with matching filenames
+ with a leading dot reported by Stephane Chazelas
+ <stephane.chazelas@gmail.com>
+ - wextglob_skipname: make analogous changes
+
+ 3/20
+ ----
+Makefile.in
+ - pass -DDEBUG down to builds in readline and history directories
+
+lib/readline/util.c
+ - _rl_trace and related functions are now only compiled in if DEBUG
+ is defined
+
+lib/readline/Makefile.in
+ - substitute @DEBUG@ and pass -DDEBUG, if necessary, to compilation
+ in LOCAL_CFLAGS
+
+ 3/21
+ ----
+parse.y
+ - shell_getc: when checking whether or not to reallocate
+ shell_input_line to add trailing newline, don't try to subtract from
+ shell_input_line_size. size_t is unsigned, so if its value is less
+ than 3 (like, say, 2), size-3 is a very large number and the string
+ will not be reallocated. Use len+3 > size instead of len > size-3.
+ Fixes bug reported in
+ https://bugs.launchpad.net/ubuntu/+source/bash/+bug/1295467
+
+ 3/27
+ ----
+lib/readline/display.c
+ - _rl_clean_up_for_exit: don't bother to call _rl_move_vert to whatever
+ readline thinks the last displayed line is if it's 0. Two reasons: a
+ minor optimization, and it protects against unwanted moving if this
+ function is called twice, as it is when ^C is pressed. Fixes bug
+ reported by Egmont Koblinger <egmont@gmail.com>
+
+ 3/28
+ ----
+bashline.c
+ - invalid_completion: new function, used to identify attempts to
+ complete words that are syntax errors
+ - attempt_shell_completion: if invalid_completion returns true for a
+ word in a command position, punt on all completions. Fixes cosmetic
+ issue reported by Uwe Storbeck <uwe@ibr.ch>
+ - attempt_shell_completion: add clause so that in_command_position
+ remains set to 1 for an empty word following a command separator like
+ (, &, or |
+
+lib/readline/kill.c
+ - rl_yank, rl_yank_nth_arg_internal: don't return -1 from bindable
+ functions, return 1 instead
+
+lib/readline/text.c
+ - rl_rubout, _rl_rubout_char, rl_delete, rl_change_case,
+ rl_transpose_chars, rl_transpose_words, _rl_set_mark_at_pos,
+ rl_exchange_point_and_mark, _rl_insert_next, _rl_char_search,
+ _rl_char_search_internal:
+ don't return -1 from bindable functions, return 1 instead
+
+lib/readline/vi_mode.c
+ - rl_vi_end_word, rl_vi_rubout, rl_vi_delete, rl_vi_char_search,
+ rl_vi_match, _rl_vi_set_mark, _rl_vi_goto_mark:
+ don't return -1 from bindable functions, return 1 instead
+
+lib/readline/macro.c
+ - rl_start_kbd_macro, rl_end_kbd_macro:
+ don't return -1 from bindable functions, return 1 instead
+
+builtins/setattr.def
+ - set_var_attribute: honor setting of no_invisible_vars when setting
+ att_invisible on a variable
+ - include "../flags.h" for no_invisible_vars
+
+builtins/declare.def
+ - declare_internal: honor setting of no_invisible_vars when setting
+ att_invisible on a variable
+ - include "../flags.h" for no_invisible_vars
+
+Makefile.in,builtins/Makefile.in
+ - make sure declare.o and setattr.o depend on flags.h
+
+execute_cmd.c
+ - decpoint: new function, returns locale's decimal point or `.' default
+ - mkfmt: use decpoint() to get decimal point instead of unconditionally
+ using `.'. Fixes bug reported by Andrey Tataranovich
+ <tataranovich@gmail.com> in debian bug 741669
+
+ 4/10
+ ----
+lib/readline/rltypedefs.h
+ - add back old Function/VFunction/etc typedefs, since other packages
+ (python, samba) use them. Mark as deprecated using gcc and clang
+ attributes. Report and fix from Max Horn <max@quendi.de>
+
+ 4/14
+ ----
+jobs.c
+ - run_sigchld_trap: unwind-protect value of this_shell_builtin, since
+ it matters in some cases whether or not we are running `wait' or
+ `eval'. Fixes bug reported by Eduardo A. Bustamante López
+ <dualbus@gmail.com>
+
+ 4/18
+ ----
+shell.h
+ - sh_parser_state_t: add `need_here_doc' flags member, since
+ xparse_dolparen (via parse_command) sets it to 0
+
+parse.y
+ - gather_here_documents: make sure need_here_doc is > 0, since we
+ don't want to just decrement it forever if it ends up < 0. Partial
+ fix for bug reported by Jared Yanovich <slovichon@gmail.com>
+ - {save,restore}_parser_state: save and restore need_here_doc flag.
+ Rest of fix for bug reported by Jared Yanovich <slovichon@gmail.com>
+
+ 4/19
+ ----
+subst.c
+ - cond_expand_word: since we are not supposed to be performing word
+ splitting here, set expand_no_split_dollar_star to 1 in addition to
+ setting W_NOSPLIT2
+ - expand_word_internal: if we have a case where we have an unquoted
+ $@ but we are in a case where we don't want to split (W_NOSPLIT2),
+ make sure we return a list consisting of a single word with the
+ arguments separated by spaces and don't do word splitting. Fixes
+ bug reported by Greg Wooledge <wooledg@eeg.ccf.org> from an IRC
+ discussion
+
+builtins/hash.def
+ - print_portable_hash_info: single-quote pathnames and hashed filenames
+ that contain shell metacharacters. Fixes bug reported by
+ <g1pi@libero.it> in debian bash bug #739853
+
+ 4/20
+ ----
+lib/readline/display.c
+ - When using horizontal scrolling, the redisplay code erases too much
+ of the line containing successful results, so make sure we only
+ erase to the end of the line after making sure we move the cursor
+ to the end. Fixes bug reported by <Trond.Endrestol@ximalas.info>
+
+ 4/23
+ ----
+{bashhist,bashline}.c
+builtins{bind,help,type}.def
+lib/glob/glob.c, lib/intl/{loadmsgcat,localealias}.c,lib/sh/mktime.c
+ - fixes to memory leaks uncovered by coverity scan
+
+ 4/24
+ ----
+{bashhist,subst,redir,assoc,jobs,array,trap}.c
+lib/intl/l10flist.c
+builtins/complete.def
+ - fixes to memory leaks and other resource usage problems uncovered by
+ coverity scan
+
+redir.c
+ - do_redirection_internal: if dup2 fails (presumably because of a
+ resource limit), close the file descriptor we opened before returning
+ error
+
+ 4/25
+ ----
+config-top.h
+ - DEFAULT_BASHRC: new define with the name of the default shell
+ startup file
+
+bashline.c
+ - bash_directory_completion_matches: don't dequote the directory name.
+ If rl_completion_found_quote is non-zero, readline will dequote the
+ filename itself. Fixes bug reported by Clark Wang
+ <dearvoid@gmail.com>
+
+ 4/27
+ ----
+subst.c
+ - parameter_brace_expand_rhs: if parameter_brace_find_indir returns
+ NULL or "", or if it returns something that is not a valid identifier,
+ report an error and return &expand_wdesc_error so the error can
+ propagate up. Fixes bug reported by Andre Holzhey
+ <andre.holzhey@gmx.de>
+
+ 4/29
+ ----
+subst.c
+ - parameter_brace_substring: don't short-circuit right away if the
+ value is NULL but we are looking at the positional parameters. Part
+ of fix for bug reported by Pierre Gaston <pierre.gaston@gmail.com>
+ - pos_params: if there are no positional parameters, only short-circuit
+ if we are looking for $1 and above. Rest of fix for bug reported
+ by Pierre Gaston <pierre.gaston@gmail.com>
+
+subst.h
+ - SD_NOPROCSUB: new flag for skip_to_delim, means to not allow any
+ process subsitutions (should not have overloaded SD_NOSKIPCMD)
+
+subst.c
+ - skip_to_delim: honor SD_NOPROCSUB flag
+
+make_cmd.c
+ - make_arith_for_expr: set W_NOPROCSUB flag in the created word
+ - make_arith_for_command: set SD_NOPROCSUB in the flags argument to
+ skip_to_delim so we don't treat <( or >( as a process substitution
+ (we won't evaluate them in eval_arith_for_expr anyway). Fixes
+ bug reported by Pierre Gaston <pierre.gaston@gmail.com>
+
+ 5/1
+ ---
+lib/glob/gmisc.c
+ - glob_dirscan: new function, takes a pattern and a directory separator
+ argument and advances the pattern to the last occurrence of the
+ separator. Like strrchr, but understands extended glob patterns and
+ uses glob_patscan to skip over them
+
+lib/glob/glob.c
+ - extglob_skipname: if the extended globbing pattern is invalid, don't
+ skip the name
+ - glob_filename: if there is a slash in the pattern to be matched, and
+ extglob is enabled, use glob_dirscan to find the real last occurrence
+ of `/' to avoid being confused by slashes in extglob patterns. Fix
+ for bug reported by Pierre Gaston <pierre.gaston@gmail.com>
+
+ 5/6
+ ---
+variables.c
+ - make_local_variable: only set the att_invisible attribute if
+ no_invisible_vars isn't set
+ - find_variable_for_assignment: new function, intended to be called by
+ code that eventually wants to assign a value to the variable; will not
+ skip invisible variables; currently identical to find_variable
+ - find_variable_no_invisible: new function, finds the first visible
+ instance of variable with a given name in the variable context chain;
+ eventually will be used to replace find_variable; separate right now
+ for testing
+
+variables.h
+ - find_variable_for_assignment: extern declaration
+ - find_variable_no_invisible: extern declaration
+
+ 5/7
+ ---
+variables.c
+ - make_local_variable: don't clear `invisible' attribute if we are
+ returning an existing local variable at the right context. Let the
+ upper layers do that. Fixes bug reported by Dan Douglas
+ <ormaaj@gmail.com>
+
+ 5/8
+ ---
+lib/readline/input.c
+ - rl_getc: call RL_CHECK_SIGNALS if a read(2) is interrupted (-1/EINTR)
+ by SIGALRM or SIGVTALRM (placeholder for non-keyboard-generated
+ signals of interest)
+
+builtins/read.def
+ - edit_line: call bashline_set_event_hook and
+ bashline_reset_event_hook around call to readline(), so the right
+ signal handling happens
+ - read_builtin: make sure we add an unwind_protect call to
+ bashline_reset_event_hook. These changes fix bug reported in
+ https://bugs.launchpad.net/ubuntu/+source/bash/+bug/1317476
+
+bashline.c
+ - bash_event_hook: make sure we clean up the readline state by calling
+ rl_cleanup_after_signal if sigalrm_seen is non-zero. The read builtin
+ sets this when it times out
+
+ 5/12
+ ----
+doc/{bash.1,bashref.texi}
+ - clarify language to make it clear that changing attributes of a
+ nameref variable (e.g., export), actually changes the attributes of
+ the referenced variable. Fixes omission noted by Jeff Haemer
+ <jeffrey.haemer@gmail.com>
+
+arrayfunc.c
+ - bind_array_var_internal: make sure ENTRY no longer has invisible
+ attribute before returning. Fixes bug reported by Geir Hauge
+ <geir.hauge@gmail.com>
+
+ 5/22
+ ----
+execute_cmd.c
+ - shell_execve: if execve fails and we return 127 or 126, make sure to
+ set last_command_exit_value if a call to file_error or report_error
+ causes the shell to exit. This ensures that the shell exits with
+ the right value.
+
+ 6/6
+ ---
+shell.c
+ - drop_priv_mode: print an error message on setuid() failure, optionally
+ exit if errno == EAGAIN, as it can be on Linux when RLIMIT_NPROC for
+ the target user is exceeded.
+
+config-top.h
+ - EXIT_ON_SETUID_FAILURE: new settable define, will cause the shell to
+ exit if setuid fails with errno == EAGAIN
+
+ 6/10
+ ----
+parse.y
+ - time_command_acceptable: fix so time is accepted everywhere the
+ grammar is looking for a `compound_list'. Fixes bug reported by
+ Dale Worley <worley@alum.mit.edu>
+
+ 6/12
+ ----
+subst.c
+ - clear_fifo_list: new function, clears FDs associated with open pipes
+ in current FIFO list without closing the file descriptors. Can
+ possibly be used when shell_execve fails and the shell jumps back
+ to top_level and we don't want the shell to close the open FIFOs
+ each time through the read-execute loop. Bug reported by Harald
+ Koenig <koenig@tat.physik.uni-tuebingen.de>
+
+
+ 6/16
+ ----
+builtins/shopt.def
+ - compat42: make sure the `compat42' option sets the correct variable
+ for compatibility level. Fixes bug reported by Ondrej Oprala
+ <ooprala@redhat.com>
+
+support/bashbug.sh
+ - fix typo when echoing $USAGE. Report from Shantanu Kulkarni
+ <djbware@shantanukulkarni.org>
+
+execute_cmd.c
+ - shell_execve: before longjmp back to subshell_top_level, clear out the
+ FIFO fd list by calling clear_fifo_list so the FDs (which we inherited
+ from our parent) aren't closed every time through the read-eval loop.
+ Fix for bug reported by Harald Koenig <koenig@tat.physik.uni-tuebingen.de>
+
+ 6/18
+ ----
+subst.c
+ - extract_process_subst: add additional argument: xflags, allow callers to
+ pass flags like extract_command_subst
+ - extract_process_subst: call xparse_dolparen like command substitution
+ to avoid problems when parsing commands constructs with embedded open
+ parens. Fixes bug reported by Tim Friske <me@timfriske.com>
+
+subst.h
+ - extract_process_subst: modified prototype for extern declaration
+
+ 6/19
+ ----
+execute_cmd.c
+ - execute_pipeline: if running with lastpipe enabled, make sure that we
+ check whether or not the job id is valid using INVALID_JOB before
+ calling job_exit_status. the jobs list can get frozen and unfrozen in
+ the presence of nested pipelines and loops and wait_for can clear a
+ job table entry. Fixes bug reported by <scorp.dev.null@gmail.com>
+
+jobs.c
+ - freeze_jobs_list: now returns old value of jobs_list_frozen; unused at
+ current time
+
+jobs.h
+ - freeze_jobs_list: change return value
+
+ 6/20
+ ----
+lib/glob/smatch.c
+ - MEMCHR: single-byte and wide character defines (memchr/wmemchr)
+
+lib/glob/sm_loop.c
+ - GMATCH: when the wildcards are the last element of the pattern, make
+ sure they do not match a string containing a `/' if FNM_PATHNAME is
+ set in FLAGS
+ - GMATCH: when recursively calling GMATCH after we see a `*', don't
+ try to consume the rest of the pattern with `*' if FNM_PATHNAME is
+ set in FLAGS, just consume up to the next slash and then see whether
+ or not the rest of the pattern matches. Fixes bug reported by Ian
+ Kelling <ian@iankelling.org>
+ - GMATCH: when processing `*' in the pattern, after skipping consecutive
+ wildcards, if we hit a literal `/' in the pattern and we're looking
+ for a pathname, skip characters in the string until we find a `/'
+ (no slash means the match fails), and try to match the rest of the
+ pattern against the portion of the string after the next `/'. Picked
+ up from gnulib/glibc
+
+pathexp.c
+ - split_ignorespec: since split_ignorespec gets globbing patterns,
+ make sure we call skip_to_delim with the SD_GLOB flag so delimiters
+ that occur within bracket expressions don't delimit the pattern.
+ Fixes problem with [[:digit:]] in GLOBIGNORE reported by Ian Kelling
+ <ian@iankelling.org>
+
+unwind_prot.c
+ - unwind_protect_tag_on_stack: new function, returns 1 if unwind-protect
+ frame corresponding to `tag' argument is on unwind-protect stack
+
+unwind_prot.h
+ - unwind_protect_tag_on_stack: extern declaration
+
+ 6/30
+ ----
+lib/readline/misc.c
+ - _rl_revert_all_lines: set entry->data to 0 after assigning it to
+ rl_undo_list to avoid pointer aliasing problems that would result
+ in entry->line being freed by an undo. The subsequent free would
+ be a double free. Report and fix from Jared Yanovich
+ <slovichon@gmail.com>
+
+subst.c
+ - command_substitute: other shells do not appear to inherit the -v
+ option when reading and executing command substitutions. Reported
+ by Ondrej Oprala <ooprala@redhat.com>
+
+ 7/1
+ ---
+config-top.h
+ - CHECKHASH_DEFAULT: new define that supplies the default value for
+ check_hashed_filenames (`checkhash' shopt option); still 0 by default
+
+findcmd.c
+ - check_hashed_filenames: initialize using CHECKHASH_DEFAULT
+
+lib/readline/histexpand.c
+ - history_expand: double quotes can inhibit recognition of the history
+ comment character if history_quotes_inhibit_expansion is non-zero
+
+lib/readline/doc/{history.3,hstech.texi}
+ - history_quotes_inhibit_expansion: expand definition to note that it
+ inhibits scanning for the history comment character as well; correct
+ typo to make it clear that it only works on double-quoted strings
+
+lib/sh/zgetline.c
+ - add new fourth argument: DELIM, allows delimiter to be something
+ other than newline (if DELIM != '\n', UNBUFFERED_READ should be
+ non-zero)
+ - UNBUFFERED_READ is now fifth argument
+ - check character against DELIM rather than strictly newline
+
+externs.h
+ - zgetline: change function prototype for extern declaration
+
+builtins/mapfile.def
+ - mapfile: change calling sequence for zgetline calls
+ - mapfile_builtin: new -d option: DELIM, like in read builtin
+ - mapfile_builtin: pass `delim' to mapfile() as new argument; default
+ to '\n' unless -d option supplied
+ - mapfile: take new DELIM argument, pass to zgetline
+ - mapfile: if DELIM != '\n', set unbuffered_read to 1
+
+doc/{bash.1,bashref.texi}
+ - mapfile: document new `-d DELIM' option
+
+ 7/5
+ ---
+lib/readline/histfile.c
+ - history_truncate_file: if there is an error writing the truncated
+ history list back to the history file, use the same strategy as
+ history_do_write: create a backup file, rename the history file to
+ the backup file, and restore the original history file from the
+ backup file name if the write or the close fails. Suggestion from
+ Chen Gang <gang.chen.5i5j@gmail.com> to bug-readline
+
+execute_cmd.c
+ - evalnest, evalnest_max: new variables establishing maximum number of
+ recursive `eval' calls; current max is 4096
+ - execute_builtin: unwind-protect value of evalnest around calls to
+ eval builtin. Suggested by Oliver Morais <oliver.morais@gmail.com>
+ - {initialize_subshell,execute_subshell_builtin_or_function}: reset
+ evalnest to 0 in a subshell
+
+builtins/setattr.def
+ - show_name_attributes: show a variable's attributes even if it's
+ invisible (don't show any value since it has none). This means that
+ declare -p var will display VAR's attributes even when var marked
+ as invisible. Feature request from Peggy Russell
+ <prusselltechgroup@gmail.com>
+ - show_var_attributes: don't print assignment if array or assoc
+ attribute is set but variable marked as invisible
+
+tests/array.right
+ - special note: changed all declare -a output tests because the shell
+ will no longer print out values for invisible array variables. This
+ is a change, but one for correctness:
+
+ declare -a foo='()'
+ and
+ declare -a foo
+ are not equivalent
+
+ 7/22
+ ----
+subst.c
+ - parameter_brace_expand: after calling parameter_brace_expand_indir,
+ turn off the W_ARRAYIND flag in the word it returns, because there
+ is no way for it to return the index that should be used, and the
+ rest of the function assumes that IND is valid if W_ARRAYIND is set.
+ Fixes bug reported by Corentin Peuvrel <cpeuvrel@pom-monitoring.com>
+
+ 8/2
+ ---
+parse.y
+ - read_token_word: if we read a character that will end a command
+ substitution, don't skip over quoted newlines when we read an
+ additional character to figure out whether it's a two-character
+ token. This lets the higher layers deal with quoted newlines after
+ the command substitution. Fixes bug reported by EmanueL Czirai
+ <amanual@riseup.net>
+
+ 8/11
+ ----
+execute_cmd.c
+ - execute_pipeline: check whether lastpipe_jid corresponds to a valid
+ job before calling append_process, for the same reason as fix from
+ 6/19. Fixes bug reported by <lolilolicon@gmail.com>
+
+ 8/12
+ ----
+lib/sh/unicode.c
+ - stub_charset: use strncpy instead of strcpy because we are copying
+ into a local fixed-length buffer. Fixes vulnerability reported by
+ <romerox.adrian@gmail.com>
+
+execute_cmd.c
+ - execute_pipeline: if we don't call append_process, call
+ wait_for_single_pid to get the status of `lastpid', since that will
+ check the status of already-reaped processes. Fixes spurious error
+ message about non-existent process from fix of 8/11
+
+ 8/15
+ ----
+jobs.c
+ - running_in_background: new variable, keeps track of whether or not we
+ are running in the background (not perfect yet)
+ - initialize_job_control: even if we are not turning on job control,
+ get the terminal pgrp so we can use it later
+ - {set_job_control,initialize_job_control}: set running_in_background
+ to 1 if terminal pgrp != shell pgrp
+ - {stop_pipeline,make_child,wait_for}: if we are running in the
+ background, don't mess with the terminal's process group; assume that
+ the parent shell will do that. Fixes bug reprted by Greg Wooledge
+ <wooledg@eeg.ccf.org>
+
+shell.c
+ - shell_reinitialize: reset running_in_background back to 0
+
+ 8/24
+ ----
+execute_cmd.c
+ - {execute_connection,execute_command_internal}: make sure that
+ asynchronous commands always set $? to 0 and are not affected by the
+ command's exit status being inverted using `!'. Fixes bug reported
+ by Vincent Lefevre <vincent@vinc17.net>
+
+lib/readline/display.c
+ - rl_message: call vsnprintf with full msg_bufsiz, since it counts
+ one fewer than the buffer length passed as an argument. Bug report
+ and fix from Dylan Cali <calid1984@gmail.com>
+
+ 8/26
+ ----
+builtins/evalstring.c
+ - evalstring: if CURRENT_TOKEN == yacc_EOF, reset it to newline. This
+ is instead of calling reset_parser(); that might still be needed.
+ Fixes bug with eval and a subsequent statement ending with EOF
+ reported by <jim.avera@gmail.org>
+
+pcomplete.c
+ - filter_stringlist: when extglob is on, a leading ! in the filter
+ pattern should be left alone when it introduces a !(pat) pattern;
+ otherwise it messes up the pattern. Fixes bug reported by David
+ Korn <dgkorn@gmail.com>
+
+ 8/27
+ ----
+doc/{bash.1,bashref.texi}
+ - clarify the behavior of bash when given the -c option, since $0 is
+ technically not a positional parameter. Bug reported by Stephane
+ Chazelas <stephane.chazelas@gmail.com>
+
+ 8/28
+ ----
+lib/readline/history.c
+ - add_history: use history_max_entries (if history is stifled) or
+ DEFAULT_HISTORY_INITIAL_SIZE if not (new define, defaults to 502)
+ to size the initial allocation of the history array. Assumption
+ is that this will reduce the number of allocations
+
+ 8/29
+ ----
+execute_command.c:
+ - sourcenest, sourcenest_max: new variables used to track level of
+ sourced files and (maybe) one day catch infinite source recursion
+ - execute_builtin: if current source level exceeds sourcenest_max,
+ trigger an error and jump back to the top level
+ - {initialize_subshell,execute_subshell_builtin_or_function}: reset
+ sourcenest to 0 in a subshell
+
+ 9/2
+ ---
+variables.c
+ - bind_variable: if a nameref expands to an array reference, make
+ sure that assign_array_element gets called (maybe even
+ recursively) instead of bind_variable_internal, so invalid variable
+ names (like arr[0]) don't get created. Fixes bug reported by
+ <lolilolicon@gmail.com>
+
+ 9/3
+ ---
+execute_cmd.c
+ - evalnest_max,sourcenest_max: initialize from EVALNEST_MAX and
+ SOURCENEST_MAX, respectively. Feature suggested by
+ <bogun.dmitriy@gmail.com>
+
+config-top.h
+ - define EVALNEST_MAX and SOURCENEST_MAX to 0
+
+ 9/6
+ ---
+bashline.c
+ - find_cmd_start: fix to (crudely) deal with >| token; even though
+ skip_to_delim finds `|' as a delimiter, we call it again and use
+ what the second call finds. Fixes bug reported by Dan Jacobson
+ <jidanni@jidanni.org>
+
+findcmd.c
+ - find_in_path_element: if in posix mode, do not expand a literal
+ tilde in a $PATH element
+
+doc/bashref.texi
+ - add change to tilde expansion in $PATH elements to posix mode
+ description
+
+builtins/common.h
+ - ISHELP: new define for builtins that do their own option parsing
+ and don't use internal_getopt(); checks whether argument is --help
+ - CHECK_HELPOPT: convenience define to help builtins that do their
+ own option parsing to check for --help with one line of code
+ - CASE_HELPOPT: convenience define to help builtins that use
+ internal_getopt() check for --help with one line of code
+
+builtins/help.def
+ - builtin_help: new function, prints out --help output for current
+ builtin
+
+builtins/{kill,let,pushd}.def
+ - add CHECK_HELPOPT to builtins that use ISOPTION; call builtin_help
+ and return EX_USAGE (kill/let/pushd/popd/dirs)
+
+builtins/{caller,fg_bg}.def
+ - use CHECK_HELPOPT to recognize --help, since these builtins perform
+ checks that can cause them to return before calling no_options
+ (caller/fg/bg)
+
+builtins/{exit,return}.def
+ - use CHECK_HELPOPT to recognize --help before calling get_exitstat()
+ (return/exit/logout)
+
+builtins/{break,shift}.def
+ - use CHECK_HELPOPT to recognize --help before any other checks
+ (break/continue/shift)
+
+builtins/bashgetopt.h
+ - GETOPT_EOF: convenience define
+ - GETOPT_HELP: new define, to indicate internal_getopt saw --help
+
+builtins/bashgetopt.c
+ - internal_getopt: return GETOPT_HELP for --help
+
+builtins/common.c
+ - no_options: recognize --help, call builtin_help and return 2
+ (builtin/eval/source/./times)
+
+builtins/command.def
+ - use CASE_HELPOPT() to handle --help after calling internal_getopt()
+ (command)
+
+builtins/{colon,echo,test}.def
+ - do not recognize --help (:/true/false/echo/test)
+
+ 9/8
+ ---
+sig.c
+ - termsig_sighandler: if readline is active now, set the bashline event
+ hook. Old code just set it for interactive shells. Part of fix for
+ bug reported by <mickael9@gmail.com>
+
+bashline.c
+ - bash_event_hook: call rl_cleanup_after_signal if terminating_signal
+ is non-zero, since check_signals_and_traps() will cause the shell to
+ exit if it is and we want to clean up the readline state first. Rest
+ of fix for bug reported by <mickael9@gmail.com>
+
+ 9/9
+ ---
+jobs.c
+ - waitchld: when running the wait builtin in posix mode, with a trap set
+ on SIGCHLD, use queue_sigchld_trap instead of trap_handler (SIGCHLD),
+ otherwise you will lose SIGCHLDs when children_exited > 1. Fixes bug
+ reported by <crispusfairbairn@gmail.com>
+
+builtins/read.def
+ - read_builtin: if we are changing the tty settings, call
+ initialize_terminating_signals so we have a chance to catch all
+ terminating signals and potentially clean up the terminal before
+ exiting
+ - read_builtin: tty_modified: new variable, set to 1 if we change the
+ terminal attributes and have to call ttyrestore() to restore them
+ - if one of the `reads' returns -1/EINTR due to a terminating signal,
+ and we have modified the terminal, call ttyrestore before calling
+ CHECK_TERMSIG
+ - ttyrestore: set tty_modified to 0 when called
+
+ 9/10
+ ----
+builtins/read.def
+ - termsave: now global to file so other functions can use it
+ - read_tty_cleanup: if tty_modified is non-zero, call ttycleanup to restore
+ old terminal settings and turn off tty_modified
+
+sig.c
+ - termsig_handler: call read_tty_cleanup if currently executing read
+ builtin; it does the right thing. Final piece of fix for bug reported
+ by Jan Rome <jan.rome@gmail.com>
+
+ 9/11
+ ----
+general.c
+ - printable_filename: general function to return a printable representation
+ of a string (presumed to be a filename)
+
+general.h
+ - extern declaration for printable_filename
+
+execute_cmd.c
+ - execute_disk_command: use printable_filename
+
+builtins/{bind,cd,enable,hash,source}.def
+ - use printable_filename as appropriate when printing error messages.
+ From a suggestion by Vincent Lefevre <vincent@vinc17.net>
+
+builtins/bind.def
+ - use CASE_HELPOPT() to handle --help after calling internal_getopt()
+ (bind)
+
+ 9/12
+ ----
+builtins/common.h
+ - SEVAL_FUNCDEF: new flag for parse_and_execute; it means that we only
+ accept a single function definition command, as when we are importing
+ functions from the environment
+ - SEVAL_ONECMD: new flag for parse_and_execute; for future use
+
+builtins/evalstring.c
+ - parse_and_execute: if the SEVAL_FUNCDEF flag is set, disallow anything
+ but a function definition command
+
+variables.c
+ - initialize_shell_variables: don't allow functions with invalid names
+ to be imported from the environment, even though we still allow them
+ to be defined
+ - initialize_shell_variables: when importing function definitions from
+ the environment, call parse_and_execute with the SEVAL_FUNCDEF flag
+ to force the command to be just a function definition
+
+subst.c
+ - param_expand: when expanding a $name variable expansion, make sure that
+ the variable is visible and set before following the nameref chain
+ - param_expand: when expanding a $name variable expansion and following the
+ nameref chain, make sure the resulting variable is visible and set
+ before using it
+
+ 9/13
+ ----
+variables.c
+ - initialize_shell_variables: when importing function definitions from
+ environment, use SEVAL_ONECMD flag for parse_and_execute. Part of
+ CVE-2014-6271
+
+builtins/evalstring.c
+ - parse_and_execute: if SEVAL_ONECMD flag set, return immediately after
+ calling execute_command_internal. Final piece for fix for bug
+ reported by Stephane Chazelas <stephane.chazelas@gmail.com>. Part of
+ CVE-2014-6271
+
+ 9/24
+ ----
+parse.y
+ - reset_parser: reset eol_ungetc_lookahead to 0 here, since we don't want
+ shell_getc returning it on the next call. Fixes problem reported by
+ Tavis Ormandy <taviso@cmpxchg8b.com> and Michal Zalewski
+ <lcamtuf@coredump.cx>. Potentially part of CVE-2014-6271; fix for
+ CVE-2014-7169
+
+ 9/25
+ ----
+parse.y
+ - push_heredoc: new function, pushes a here-doc redirection onto
+ redir_stack handling overflow of redir_stack. Exits on overflow.
+ Original fix from Florian Weimer <fweimer@redhat.com>. Fix for
+ CVE-2014-7186
+ - change straight assignments to redir_stack to call push_redir
+ - add one to size of word_lineno stack to avoid off-by-one error
+ below in read_token_word. Overflow just results in line numbers
+ being wrong. Fix for CVE-2014-7187
+
+ 9/27
+ ----
+{execute_cmd,trap}.c
+ - changes to make minimal-config builds work again, mostly missing
+ #ifdefs for optional features
+
+builtins/common.c
+ - builtin_help: dummy version to be included if HELP_BUILTIN not
+ defined, for minimal-config builds
+
+variables.c
+ - initialize_shell_variables: incorporated patches from Florian
+ Weimer <fweimer@redhat.com> to change the strings bash looks
+ for when importing shell functions from the environment. It
+ adds a prefix (BASH_FUNC_) and a suffix (%%) to the name to
+ mark it as having been created by bash as an exported function.
+ Fix for remote attacks part of CVE-2014-6271 and CVE-2014-7169
+ - mk_env_string: takes new argument, indicating whether we are
+ constructing a function
+ - mk_env_string: encodes function names as described above, so
+ initialize_shell_variables can find them
+
+ 9/28
+ ----
+copy_cmd.c
+ - copy_redirects: before calling savestring on here_doc_eof, make
+ sure it's not NULL (it could have been the result of a here
+ document delimited by EOF or EOS). Fixes bug reported by
+ Michal Zalewski <lcamtuf@coredump.cx>. Fix for CVE-2014-6277
+
+make_cmd.c
+ - make_redirection: initialize here_doc_eof member to NULL. Rest of
+ fix for CVE-2014-6277
+
+ 9/29
+ ----
+parse.y
+ - current_input_line_state: return a sh_input_line_state_t containing
+ the current shell_input_line and its index and size variables
+
+shell.h
+ - current_input_line_state: extern declaration
+
+builtins/evalstring.c
+ - parse_and_execute: call reset_parser() before returning if
+ SEVAL_ONECMD set. Fixes bug reported by Michal Zalewski
+ <lcamtuf@coredump.cx> and designated CVE-2014-6278
+ - parse_and_execute: if we parse a function definition when
+ SEVAL_FUNCDEF is set, but don't consume the entire passed string,
+ throw an error, reset the parser, and return. Part of fix for
+ CVE-2014-6278
+ - parse_and_execute: if parsing the shell function definition when
+ SEVAL_FUNCDEF is set transforms the function name (e.g., if it
+ begins with a newline or begins or ends with whitespace), throw
+ an error, reset the parser, and return. Fixes bug reported by
+ Eric Kobrin <ekobrin@akamai.com>
+
+ 10/2
+ ----
+jobs.c
+ - bgp_prune: don't do anything if bgpids.npid == 0 or bgpids.list == NULL.
+ This can happen if something gets run before the job control framework
+ is initialized. Bug report from <mancha1@zoho.com>
+
+ 10/3
+ ----
+parse.y
+ - xparse_dolparen: don't set token_to_read to newline after calling
+ parse_string() and cleaning up when the shell is not interactive. This
+ makes the parser thing it's ok to read new commands even if it's not in
+ a state where that should be possible. Underlying fix for bug reported
+ by Michal Zalewski <lcamtuf@coredump.cx> and designated CVE-6278
+ - parser_remaining_input: new function, returns the portion of
+ shell_input_line that hasn't yet been read
+ - current_input_line_state: removed
+
+shell.h
+ - parser_remaining_input: extern declaration
+ - current_input_line_state: removed
+
+builtins/evalstring.c
+ - parse_and_execute: change code that checks whether parse_command has
+ consumed the entire passed string when SEVAL_FUNCDEF is used to use
+ parser_remaining_input instead of messing around with (new)
+ current_input_line_state. Part of fix for CVE-2014-6278
+
+variables.c
+ - initialize_shell_variables: if we don't call parse_and_execute, free the
+ temporary string, since parse_and_execute won't. Report and fix from
+ Eric Kobrin <ekobrin@akamai.com>
+
+ 10/4
+ ----
+print_cmd.c
+ - print_function_def: when in posix mode, print shell function
+ definitions as posix specifies them, without the leading
+ `function' keyword
+
+general.c
+ - exportable_function_name: return 1 if the passed string can be
+ added to the environment as an exported function name. Currently
+ prohibits function names containing `/' and `=' from being
+ exported
+
+general.h
+ - exportable_function_name: extern declaration
+
+builtins/setattr.def
+ - set_or_show_attributes: if exporting a function with export -f,
+ call exportable_function_name to determine whether the function
+ should be exported; don't export function if it returns 0
+
+ 10/7
+ ----
+builtins/setattr.def
+ - set_or_show_attributes: don't show identifiers that are invisible
+ and imported from the environment, since that combination of
+ attributes means that the imported variable is not a valid shell
+ identifier. Report from Stephane Chazelas <stephane.chazelas@gmail.com>
+
+ 10/8
+ ----
+shell.c
+ - shell_initialize: set new variable should_be_restricted, which
+ says whether or not the shell will be a restricted one based on the
+ shell name; use in calls to initialize_shell_variables (to inhibit
+ importing shell functions) and initialize_shell_options (to inhibit
+ parsing $SHELLOPTS) and initialize_bashopts (to inhibit parsing
+ $BASHOPTS). Report from <paulfm@umn.edu>
+
+ 10/12
+ -----
+execute_cmd.c
+ - execute_function: unwind-protect loop_level, set loop_level to 0
+ when entering a function so break and continue in functions don't
+ break loops running outside of the function. Fix picked up from
+ dash via Herbert Xu <herbert@gnodor.apana.org.au>
+
+ 10/13
+ -----
+doc/Makefile.in
+ - bashref.pdf: create using texi2dvi --pdf rather than postprocessing the
+ dvi file, so we have PDF bookmarks and links. Fix from
+ Siep Kroonenberg <siepo@cybercomm.nl>
+
+ 10/14
+ -----
+subst.h
+ - Q_ARITH: new quoting flag. Semantics are per Posix's spec for arithmetic
+ expansion: act as if string is quoted, but don't treat double quotes
+ specially (in this case, they will be removed by quote removal)
+ - Q_ARRAYSUB: new quoting flag, indicates we are expanding an indexed array
+ subscript
+
+subst.c
+ - expand_arith_string: if we are not expanding the string, but we saw a quote
+ with Q_ARITH specified as one of quoting flags, perform quote removal even
+ if Q_DOUBLE_QUOTES is specified
+ - param_expand: change calls to expand_arith_string for $[ and $(( cases to
+ specify Q_ARITH. Now $(( "$x" )) and $(( "x" )) work if x has a value that
+ evaluates to a valid number, as Posix specifies
+ - expand_word_internal: add test for quoted&Q_ARITH to the tilde case, so we
+ continue to perform tilde expansion in arithmetic contexts
+ - expand_word_internal: if quoted&Q_ARITH, continue processing when we see a
+ `"', acting as if the double quote isn't present (already Q_DOUBLE_QUOTED)
+
+arrayfunc.c
+ - array_expand_index: pass Q_DOUBLE_QUOTED|Q_ARITH|Q_ARRAYSUB as quoted argument
+ in call to expand_arith_string. This inhibits word splitting
+ (Q_DOUBLE_QUOTED) while discarding double quotes (Q_ARITH), identical to the
+ quote flags passed while expanding $(( )) and $[ ]. Q_ARRAYSUB reserved for
+ future use. Fixes problem reported by Stephane Chazelas
+ <stephane.chazelas@gmail.com>
+
+ 10/16
+ -----
+subst.c
+ - parameter_brace_expand_word: if the PF_ASSIGNRHS flag is set and we
+ are expanding what looks like an array subscripted with @ or *,
+ make sure the variable we're expanding is actually an array before
+ we add Q_DOUBLE_QUOTES to the flags. If we don't, things like
+ scalar[@] will remain quoted. Fixes ubuntu bug 1381567
+ https://bugs.launchpad.net/ubuntu/+source/bash/+bug/1381567
+
+ 10/17
+ -----
+{jobs,nojobs}.c
+ - get_original_tty_job_signals: get original signal dispostions for
+ SIGTSTP, SIGTTIN, SIGTTOU before we start manipulating them in
+ make_child
+ - default_tty_job_signals: make sure we set SIGTSTP, SIGTTIN, or
+ SIGTTOU to SIG_IGN if they were ignored at shell startup instead of
+ unconditionally setting them to SIG_DFL. Fixes bug reported by
+ idallen@idallen.ca
+
+jobs.h
+ - get_original_tty_job_signals: extern declaration
+
+trap.c
+ - initialize_traps: add call to get_original_tty_job_signals
+
+ 10/22
+ -----
+subst.c
+ - expand_string_for_rhs: when expanding in this context (rhs of a word
+ expansion or pattern removal), we don't perform word splitting, so
+ we don't want to split $* if IFS is empty. Fixes bug reported by
+ Stephane Chazelas <stephane.chazelas@gmail.com>
+
+ 10/23
+ -----
+subst.c
+ - param_expand: when expanding $* in a pattern context where the
+ expansion is quoted (Q_PATQUOTE), don't quote the expansion --
+ the outer quotes don't make the characters in the expansion of
+ $* special. Posix interp 221. Reported by Stephane Chazelas
+ <stephane.chazelas@gmail.com>
+
+ 10/28
+ -----
+lib/readline/bind.c
+ - enable-bracketed-paste: new bindable variable, enables support for
+ a terminal's `bracketed paste mode'. Code contributed by
+ Daniel Colascione <dancol@dancol.org>
+
+doc/bash.1,lib/readline/doc/{readline.3,rluser.texi}
+ - enable-bracketed-paste: add description
+
+lib/readline/{readline.c,rlprivate.h}
+ - _rl_enable_bracketed_paste: declarations
+ - #defines for use by bracketed paste implementation
+
+lib/readline/rltty.c
+ - rl_prep_terminal: send BRACK_PASTE_INIT string to terminal if we
+ are supposed to enable bracketed-paste mode; change terminal_prepped
+ to indicate we sent that string and need to clean up
+ - rl_deprep_terminal: if terminal_prepped indicates we sent the
+ bracketed-paste mode init string to the terminal, send the cleanup
+ string before restoring the terminal modes
+
+lib/readline/kill.c
+ - rl_bracketed_paste_begin: function to read bracketed paste until
+ BRACK_PASTE_SUFF; discard the suffix, and insert the rest of the
+ paste as a single (undoable) object. Bound to BRACK_PASTE_PREF
+
+lib/readline/funmap.c
+ - bracketed-paste-begin: new bindable command, executes
+ rl_bracketed_paste_begin
+
+lib/readline/readline.c
+ - bind_bracketed_paste_prefix: new function, sets up to recognize
+ the bracketed paste prefix sequence (BRACK_PASTE_PREF) in emacs
+ keymap and vi insertion keymap
+ - readline_initialize_everything: call bind_bracketed_paste_prefix
+
+ 11/1
+ ----
+builtins/ulimit.def
+ - RLIMIT_POSIXLOCKS: now synonym for RLIMIT_LOCKS
+ - -k: new option: RLIMIT_KQUEUES, max kqueues allocated for this
+ process
+ - -P: new option: RLIMIT_NPTS, max number of pseudoterminals available
+ to this process
+
+doc/{bash.1,bashref.texi}
+ - document `ulimit -k' option
+ - document `ulimit -P' option
+
+parse.y
+ - `timespec list_terminator' production: if the list terminator is `;'
+ set last_read_token to `;' to allow things like `time ; command' to
+ time null commands and not throw a syntax error. Patch from
+ Piotr Grzybowski <narsil.pl@gmail.com>
+ - `BANG list_terminator' production: do the same thing
+
+variables.c
+ - sv_optind: use find_shell_variable and get_variable_value so we can
+ have the variable's context in the case we need to do something
+ when we are restoring a previous variable context's value
+
+builtins/getopt.h
+ - sh_getopt_state_t: struct to save sh_getopt's internal state so we
+ can restore it around function calls in the event that we have a
+ local copy of OPTIND
+
+builtins/getopt.[ch]
+ - sh_getopt_{save,restore}_istate: new functions to save and restore
+ getopt's internal state
+ - sh_getopt_{alloc,dispose}_istate: new functions to allocate and
+ deallocate sh_getopt_istate_t objects
+
+execute_cmd.c
+ - maybe_restore_getopt_state: restore sh_getopt state after executing
+ function body iff the funtion declared a local copy of OPTIND
+ - execute_function: save sh_getopt state before executing function body
+ - execute_function: note in getopt_state->flags whether or not the
+ function declared a local copy of OPTIND; used by maybe_restore_getopt_state
+ - execute_function: maybe restore sh_getopt state before returning via
+ call to maybe_restore_getopt_state. Fixes bugs with getopts and
+ state between calls reported in 2011 by Bernd Eggink <monoped@sudrala.de>
+ and in 2014 by Oyvind Hvidsten <oyvind.hvidsten@dampir.no>
+
+configure.ac
+ - enable-function-import: new option, controls whether function imports
+ are included. Enabled by default. Patch from David Galos
+ <davegalos@google.com>
+
+config.h.in
+ - FUNCTION_IMPORT: define controlled by enable-function-import above
+
+variables.c
+ - initialize_shell_variables: include code to import function definitions
+ from the environment if FUNCTION_IMPORT is defined
+
+doc/bashref.texi
+ - --enable_function-import: document new configuration option
+
+ 11/5
+ ----
+lib/readline/history.c
+ - history_lines_read_from_file: new variable, set by read_history and
+ read_history_range to the actual number of lines read from the
+ history file. The value is valid immediately after a call to one
+ of those functions
+ - history_lines_written_to_file: new variable, set by write_history,
+ history_do_write, and history_truncate_file to the actual number of
+ lines written to the history file. The value is valid immediately
+ after a call to one of those functions
+
+variables.c
+ - sv_histsize: set history_lines_in_file after history_truncate_file()
+ only if hmax < history_lines_in_file (lines we've already read); a
+ cosmetic change only
+
+bashhist.c
+ - load_history: set history_lines_in_file after read_history() from
+ history_lines_read_from_file, since read_history reads all of the
+ lines from the history file even if it's more than $HISTSIZE
+ - maybe_save_shell_history: after calling write_history(), set
+ history_lines_in_file to history_lines_written_to_file, since we
+ can assume that we read everyhing we just wrote
+
+builtins/history.def
+ - history_builtin: after calling read_history (history -r), set the
+ new value of history_lines_in_file, for the same reason as above
+ - history_builtin: after calling read_history_range (history -n), set
+ history_lines_in_file from history_lines_read_from_file
+
+ 11/6
+ ----
+lib/readline/histfile.c
+ - history_truncate_file: since we move the old file to a backup copy
+ before truncating, make sure the new file is owned by the same uid
+ as the old
+ - history_do_write: use chown in the same way as history_truncate_file
+
+ 11/12
+ -----
+lib/readline/display.c
+ - expand_prompt: takes a new `flags' argument; only one flag defined
+ so far: PMT_MULTILINE
+ - expand_prompt: changed all callers to add new flags argument
+ - rl_expand_prompt, redraw_prompt: make sure to set PMT_MULTILINE in
+ FLAGS argument to expand_prompt if expanding parts of a prompt
+ containing embedded newlines
+ - expand_prompt: only add mode char to last line of a prompt with
+ embedded newlines, so mode indicator doesn't get lost and gets
+ updated properly. Fixes problem reported by Renlin Li
+ <lirenlin@gmail.com>
+
+ 11/13
+ -----
+
+lib/readline/display.c
+ - prompt_modestr: changed prompt_modechar to return a string denoting
+ the editing mode; default strings for emacs and both vi modes are
+ #defines in this file. prompt_modestr takes an argument in which
+ it returns the length of the mode string
+ - expand_prompt: if expanding mode strings in the prompt, get the
+ mode string to use and add it at the beginning of the prompt string,
+ before expanding it. This will allow future work allowing the mode
+ string to contain invisible characters
+
+ 11/15
+ -----
+lib/readline/rlprivate.h
+ - _rl_{emacs,vi_cmd,vi_ins}_mode_str: extern declarations for
+ variables to hold current values of user-settable mode strings;
+ variables to hold lengths
+
+lib/readline/rlconf.h
+ - defines for default values of the mode strings for each editing mode
+ and keymap
+
+lib/readline/display.c
+ - _rl_{emacs,vi_cmd,vi_ins}_mode_str: new variables to hold values of
+ user-settable mode strings
+ - _rl_{emacs,vi_cmd,vi_ins}_modestr_len: new variables to hold lengths
+ of corresponding mode string variables
+ - prompt_modestr: return appropriate user-settable mode string
+ variables
+
+lib/readline/bind.c
+ - {emacs,vi-ins,vi-cmd}-mode-string: new user-settable mode string
+ variables
+ - sv_{emacs,viins,vicmd}_modestr: variable handling functions for user-
+ settable mode string variables. Non-null values are run through
+ rl_translate_keyseq so users can include invisible character
+ sequences in the mode strings; null values restore the default
+ - _rl_get_string_variable_value: handle values for new user-settable
+ mode string variables. Original code contributed by Dylan Cali
+ <calid1984@gmail.com>
+
+lib/readline/doc/rluser.texi
+ - {emacs,vi-ins,vi-cmd}-mode-string: document, including the fact that
+ you can use \1 and \2 to bracket sequences of non-printing
+ characters
+
+ 11/16
+ -----
+lib/readline/history.c
+ - add_history: replace loop that copies history list down one item
+ with call to memmove to take advantage of whatever efficiencies
+ libc can offer. Won't be any slower than current loop
+
+lib/readline/display.c
+ - rl_redraw_prompt_last_line: new function, calls redraw_prompt if
+ the prompt contains multiple lines; calls rl_forced_update_display
+ if not
+
+lib/readline/readline.h
+ - rl_redraw_prompt_last_line: extern declaration, undocumented in
+ texinfo manual until I get it a little more work
+
+bashline.c
+ - bash_execute_unix_command: instead of unconditionally calling
+ rl_forced_update_display, call rl_redraw_prompt_last_line if we
+ cleared the last line before executing the command. This keeps
+ commands that don't display any other output but just manipulate
+ the contents of the line buffer from redisplaying the prompt lines
+ before the last newline multiple times. Fixes bug reported by
+ Jesper Nygards <jesper.nygards@gmail.com> and Rob Foehl
+ <rwf@loonybin.net>. This means that commands that display output
+ will *only* display the final line of the prompt
+ - bash_execute_unix_command: if the command returns 124, we redraw
+ the line unconditionally, including all lines of the prompt
+
+ 11/18
+ -----
+builtins/mapfile.def
+ - mapfile_builtin: don't allow a valid array reference through to
+ mapfile(), since it will just create a shell variable with that name.
+ Bug and fix from Eduardo A. Bustamante López <dualbus@gmail.com>
+
+ 11/19
+ -----
+lib/readline/complete.c
+ - _rl_colored_completion_prefix: new variable, if non-zero, and color
+ support is compiled in, and the $LS_COLORS variable exists and
+ contains color definitions, display any common prefix of a set of
+ completions in blue when displaying all the possible completions.
+ Doesn't work with menu-complete, which inserts possible completions
+ inline
+ - colored_prefix_start(), colored_prefix_end(): new functions, used to
+ bracket colored completion prefixes
+ - fnprint: if prefix_bytes is non-zero, and _rl_colored_completion_prefix
+ is > 0, display the first PREFIX_BYTES bytes of the word bracketed
+ by calls to colored_prefix_start and colored_prefix_end
+ - print_filename: if _rl_colored_completion_prefix is > 0, compute the
+ length in bytes of the common prefix and pass that to fnprint
+
+lib/readline/readline.c
+ - readline_initialize_everything: initialize the colors from $LS_COLORS
+ if _rl_colored_completion_prefix is non-zero
+
+lib/readline/colors.c
+ - _rl_print_prefix_color: new function, changes text color to that
+ defined for the common prefix of a set of possible completions
+ (currently cyan, same as directories); currently uses C_PREFIX,
+ defined in colors.h as C_DIR
+
+lib/readline/colors.h
+ - _rl_print_prefix_color: new extern declaration
+
+lib/readline/bind.c
+ - colored-completion-prefix: new bindable variable, if set, common
+ prefix of a set of possible completions is displayed in color.
+ Feature requested by several, most recently by Richard Neill
+ <rn214@richardneill.org> (in a slightly different form) and
+ Duy Nguyen <pclouds@gmail.com>
+
+ 11/20
+ -----
+builtins/printf.def
+ - printf_builtin: allow null (empty) format strings supplied with
+ -v var to set `var' to the empty string. That is, printf -v var ""
+ is now the same as var="". Change suggested by Mike Frysinger
+ <vapier@gentoo.org>
+
+pathexp.h
+ - FNMATCH_NOCASEGLOB: macro to decide whether or not to pass
+ FNM_CASEFOLD flag to strmatch depending on whether glob_ignore_case
+ is set; analogout to FNMATCH_IGNCASE
+
+pathexp.c
+ - glob_name_is_acceptable: use FNMATCH_NOCASEMATCH to determine flags
+ passed to strmatch; if nocaseglob is used to generate glob matches,
+ it should be used to generate ignored matches
+
+ 11/21
+ -----
+pcomplete.c
+ - filter_stringlist: the call to strmatch now honors the setting of
+ nocasematch. Feature request from Ville Skytta <ville.skytta@iki.fi>
+ back in 2010
+
+doc/bash.1,lib/readline/doc/rluser.texi
+ - complete -X: document that filtering the list of possible completions
+ honors the nocasematch option when performing matching
+
+lib/glob/gmisc.c
+ - include chartypes.h and strmatch.h for new defines
+ - match_pattern_{wchar,char}: now take new third FLAGS argument, flags
+ have same meanings as strmatch(); intent is to handle case
+ insensitive comparisons under same conditions as strmatch
+ - FOLD: imported case-folding define from sm_loop.c; wide and single-
+ byte character versions
+ - match_pattern_{wchar,char}: use FOLD when comparing characters to
+ honor FNM_CASEFOLD if set in FLAGS argument
+
+externs.h
+ - match_pattern_{wchar,char}: updated extern declarations
+
+subst.c
+ - match_{upattern,wpattern}: update strmatch/wcsmatch calls to include
+ FNMATCH_IGNCASE in flags argument
+ - match_{upattern,wpattern}: update match_pattern_{char,wchar} calls
+ to include FNMATCH_IGNCASE in flags argument (consistent with calls
+ to strmatch). This makes pattern substitution word expansion honor
+ nocasematch shell option. Feature requested by Davide Baldini
+ <baldiniebaldini@gmail.com>
+ - match_wpattern: make sure to fold case if necessary when doing simple
+ matching
+
+doc/{bash.1,bashref.texi}
+ - pattern substitution: updated description to include honoring setting
+ of nocasematch when performing matching
+
+subst.c
+ - expand_word_internal: optimize handling of "$@" idiom by calling
+ list_rest_of_args() and quote_list() directly at the top of the
+ function instead of going through normal code path
+ - cached_quoted_dollar_at: WORD_LIST of quoted positional parameters,
+ used by same code above that optimizes "$@"; if non-null we just
+ return a copy of the list; if null, we save a copy of the list we
+ create
+ - invalidate_cached_quoted_dollar_at: convenience function to allow
+ other parts of the shell (e.g., remember_args()) to destroy the
+ cached list of quoted positional parameter when the positional
+ parameters change
+
+builtins/common.c
+ - remember_args: call invalidate_cached_quoted_dollar_at()
+
+builtins/shift.def
+ - shift_builtin: call invalidate_cached_quoted_dollar_at after modifying
+ dollar_vars[]
+
+builtins/source.def
+ - maybe_pop_dollar_vars: call invalidate_cached_quoted_dollar_at just
+ to be safe
+
+ 11/23
+ -----
+builtins/evalfile.c
+ - _evalfile: return -1 if errno == ENOENT and the flags don't include
+ FEVAL_ENOENTOK. If we print an error message we should return an
+ error
+ - force_execute_file: new function, reads and executes commands from
+ a file but returns an error if file doesn't exist
+
+builtins/common.h
+ - force_execute_file: new extern declaration
+
+shell.c
+ - main: call start_debugger even if dollar_vars[1] == 0 if the shell
+ isn't interactive (interactive_shell == 0)
+ - start_debugger: call force_execute_file instead of maybe_execute_file;
+ turn off debugging mode if it returns value < 0
+
+ 11/24
+ -----
+hashlib.h
+ - DEFAULT_HASH_BUCKETS: doubled to 128, cost in memory use is small but
+ changes traversal order when not sorting results
+
+ 11/25
+ -----
+doc/{bash.1,bashref.texi}
+ - make it clearer, by breaking it out into a separate paragraph, that
+ referencing an array without a subscript is equivalent to referencing
+ it with subscript 0
+ - add text saying that referencing any variable using a valid subscript
+ is OK
+
+ 11/28
+ -----
+
+arrayfunc.c
+ - bind_array_variable, bind_assoc_variable: allow binding value to a
+ readonly variable if the ASS_FORCE flag is set in the FLAGS
+ argument
+
+subst.h
+ - ASS_FORCE: new assignment flag; means to allow assignment even if
+ variable is marked readonly
+
+builtins/declare.def
+ - when assigning a value to an array or assoc variable using
+ something like `declare -r foo=bar' where foo is an existing array
+ variable, pass the ASS_FORCE to assign_array_var_from_string so
+ the assignment is allowed. Fixes debian bug 765759
+ http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=765759
+
+builtins/setattr.def
+ - var_attribute_string: new function to return (as argument) a char
+ array with attribute flag values for a given variable; returns the
+ length of the array
+
+lib/sh/shquote.c
+ - sh_quote_reusable: function returning a version of its string
+ argument that is quoted for reuse
+
+externs.h
+ - sh_quote_reusable: extern declaration
+
+builtins/common.h
+ - MAX_ATTRIBUTES: define used to size arrays for attribute flag
+ characters
+ - var_attribute_string: new extern function declaration
+
+subst.c
+ - array_remove_pattern: fixed a bug where `var' instead of `v' was
+ tested for invisible attribute
+ - get_var_and_type: fill in a valid *VARP if returning VT_VARIABLE
+ because callers may need to use it
+ - parameter_brace_transform: family of functions to implement the new
+ mksh-inspired ${param@spec} transformation word expansions. Some
+ of the operators transform the (expanded) value of the parameter,
+ the rest expand to information about the parameter itself
+ (array_transform, parameter_list_transform, list_transform,
+ string_transform, pos_params_assignment, array_var_assignment,
+ string_var_assignment)
+ - parameter_brace_expand: changes to parse the new `@' word expansion
+ operator and call parameter_brace_transform appropriately
+ - parameter_brace_expand: make sure we handle ${#@} as we have before
+ even in the presence of the new `@' operator
+
+variables.c
+ - push_temp_var: make sure to call bind_variable_internal with the
+ ASS_FORCE flag so we override readonly variables created with
+ something like `tempvar=foo declare -r foo'.
+ - bind_variable_internal: honor ASS_FORCE flag to allow binding even
+ if a variable is readonly
+
+execute_cmd.c
+ - struct func_array_state: new state to save state of BASH_LINENO,
+ BASH_SOURCE, and FUNCNAME during function execution so it can be
+ restored on a jump to top level
+ - restore_funcarray_state: new function to restore func_array_state
+ - execute_function: fill in func_array_state variable, add unwind-
+ protect to restore it on jump to top level, call explicitly at
+ end of function if subshell != 0 (may not be necessary, but safe
+ for now). Fixes bug with local assignments to FUNCNAME reported
+ by Arfrever Frehtes Taifersar Arahesis <arfrever.fta@gmail.com>
+
+ 11/29
+ -----
+arrayfunc.c
+ - assign_compound_array_list: turn off ASS_APPEND flag when processing
+ each individual assignment inside the parens in var+=(...). The
+ outer += should not affect assignments to existing subscripts;
+ those should be treated like usual assignments unless += supplied
+ inside the parens. Bug report from Maarten Billemont
+ <lhunath@lyndir.com>, fix from Eduardo A. Bustamante López
+ <dualbus@gmail.com>
+
+config.h.in
+ - HAVE_PSELECT: define if pselect(2) available
+
+configure.ac
+ - check for pselect(2), define HAVE_PSELECT if found
+
+lib/readline/input.c
+ - rl_getc: use pselect(2) to wait for input ready on readline's
+ input fd or for a signal to arrive, will handle SIGWINCH (which
+ does not interrupt read(2)) and thus allow resize to happen without
+ having to wait to read more input. Only works if pselect available
+ and returns -1/EINTR on a signal even if the signal was installed
+ with SA_RESTART. From a suggestion from Egmont Koblinger
+ <egmont@gmail.com>
+
+ 12/3
+ ----
+variables.c
+ - flush_temporary_env: new function, disposes all temp variables in
+ temporary_env hash table
+ - bind_variable: only try to update a temporary variable's value in the
+ temporary env if the value argument is not null. Fixes bug reported
+ by <tangqinghao@360.cn>
+
+variables.h
+ - flush_temporary_env: new extern declaration
+
+subst.c
+ - command_substitute: if running command substitution as part of
+ expanding a redirection (expanding_redir == 1), flush any temporary
+ environment we've inherited as part of this command, since we are not
+ supposed to have access to the temporary environment. Since
+ expanding_redir only controls access to the temporary environment for
+ variable lookup and binding, we can turn it off in the subshell
+
+ 12/4
+ ----
+builtins/printf.def
+ - printstr: make sure a missing precision specifier after a `.' is
+ treated as 0, as printf(3) specifies. Fixes ubuntu bash bug
+ 1399087 (https://bugs.launchpad.net/ubuntu/+source/bash/+bug/1399087)
+
+ 12/5
+ ----
+subst.c
+ - skip_to_delim: if scanning past process substitution (skipcmd == 1,
+ noprocsub == 0), use extract_delimited_string instead of
+ extract_process_subst, which was changed a while back (bash-4.3.23)
+ to use xparse_dolparen. xparse_dolparen complains if the command
+ or process substitution is unterminated, since it runs the parser,
+ which is not what we want here. Command substitution does the same
+ thing. Fixes bug reported by Daniel Kahn Gillmor
+ <dkg@fifthhorseman.net> as Debian bash bug 771968
+ (https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=771968)
+
+ 12/6
+ ----
+subst.c
+ - command_substitute: short-circuit without forking on a command string
+ that consists entirely of <blank>s and newlines
+
+jobs.c
+ - make_child: changes to allow interrupts through if fork fails and
+ we are sleeping for `forksleep' seconds
+ - waitchld: make things a little more resilient if CHILD ends up NULL
+
+ 12/12
+ -----
+lib/readline/complete.c
+ - rl_display_match_list: when calculating common prefix to display in
+ color, make sure we correctly handle a common prefix with a trailing
+ `/' as we do when checking whether or not to add an ellipis.
+ printable_part() doesn't return the whole pathname if it ends in a
+ slash, to avoid printing null strings, so we have to make sure we
+ have the entire prefix
+
+lib/readline/complete.c
+ - _rl_complete_display_matches_interrupt: new variable, set to 1 by
+ _rl_complete_sigcleanup to let rl_display_match_list know it has
+ freed the match list
+ - display_matches: check for signals during the printing loops with
+ RL_SIG_RECEIVED(), return immediately if there is a pending signal
+ (might not want to do this if it's SIGWINCH -- CHECK)
+ - rl_complete_internal: if _rl_complete_display_matches_interrupt
+ set after calling display_matches, just null out `matches' since
+ it's already been freed and call any application-set signal hook
+
+ 12/14
+ -----
+parse.y
+ - time_command_acceptable: if the token before a newline is `|',
+ return 0, since it's not really valid to time inside a pipeline.
+ Only handles a single newline but allows things like
+ echo a |
+ time cat
+ to invoke /usr/bin/time, which is probably enough to catch the
+ stray carriage return. Fixes bug reported by Andre Majorel
+ <aym-ung@teaser.fr>
+
+builtins/declare.def
+ - declare_internal: don't try to perform compound assignments unless
+ the WORD_DESC has flags including W_COMPASSIGN (maybe should check
+ W_ASSIGNMENT as well), avoiding unexpected evaluation if a word
+ is of the form (word) and is assigned to an array variable like so:
+ declare -x var=$value. Bug reported by Stephane Chazelas
+ <stephane.chazelas@gmail.com>. Will eventually be contingent on
+ compatibility level > 43, but not there yet
+
+ 12/15
+ -----
+lib/sh/Makefile.in
+ - add missing dependencies for shmatch.o. Pointed out by Sergey
+ Mikhailov <sergey.mikhailov@gmail.com>
+
+ 12/16
+ -----
+{execute_cmd,subst}.c
+ - W_ASSIGNINT: remove, not used any more
+
+execute_cmd.c
+ - fix_assignment_words: don't look for `-i' option and set W_ASSIGNINT
+ flag any more; doing things a different way
+ - shell_expand_word_list: instead of using W_ASSIGNINT flag, since it
+ doesn't take into account all options that can transform values on
+ assignment (-l/-u/-c can also), go through option arguments looking
+ for options that need special handling and add them to the `opts'
+ array for make_internal_declare to use. Fixes bug with constructs
+ like `declare -al foo=(UPONE UPTWO UPTHREE)' not being lowercased on
+ assignment reported by Linda Walsh <bash@tlinx.org>
+
+ 12/18
+ -----
+lib/readline/readline.c
+ - rl_internal_char: when we read EOF on a non-empty line, check for
+ signals and invoke any readline signal handling and any application-
+ installed signal hook
+
+ 12/20
+ -----
+lib/readline/readline.c
+ - rl_internal_char: if we read EOF on a non-empty line, set c to
+ _rl_eof_char the first time through. If we read EOF the next time,
+ return EOF from readline(). If callbacks are defined, this returns
+ EOF immediately, since lastc isn't available
--- /dev/null
+Starting bash with the `--posix' command-line option or executing
+`set -o posix' while bash is running will cause bash to conform more
+closely to the Posix.2 standard by changing the behavior to match that
+specified by Posix.2 in areas where the bash default differs.
+
+The following list is what's changed when `posix mode' is in effect:
+
+1. When a command in the hash table no longer exists, bash will re-search
+ $PATH to find the new location. This is also available with
+ `shopt -s checkhash'.
+
+2. The >& redirection does not redirect stdout and stderr.
+
+3. The message printed by the job control code and builtins when a job
+ exits with a non-zero status is `Done(status)'.
+
+4. Reserved words may not be aliased.
+
+5. The Posix.2 PS1 and PS2 expansions of `!' -> history number and
+ `!!' -> `!' are enabled, and parameter expansion is performed on
+ the value regardless of the setting of the `promptvars' option.
+
+6. Interactive comments are enabled by default. (Note that bash has
+ them on by default anyway.)
+
+7. The Posix.2 startup files are executed ($ENV) rather than the normal
+ bash files.
+
+8. Tilde expansion is only performed on assignments preceding a command
+ name, rather than on all assignment statements on the line.
+
+9. The default history file is ~/.sh_history (default value of $HISTFILE).
+
+10. The output of `kill -l' prints all the signal names on a single line,
+ separated by spaces.
+
+11. Non-interactive shells exit if `file' in `. file' is not found.
+
+12. Redirection operators do not perform pathname expansion on the word
+ in the redirection unless the shell is interactive
+
+13. Function names must be valid shell identifiers. That is, they may not
+ contain characters other than letters, digits, and underscores, and
+ may not start with a digit. Declaring a function with an illegal name
+ causes a fatal syntax error in non-interactive shells.
+
+14. Posix.2 `special' builtins are found before shell functions during command
+ lookup.
+
+15. If a Posix.2 special builtin returns an error status, a non-interactive
+ shell exits. The fatal errors are those listed in the POSIX.2 standard,
+ and include things like passing incorrect options, redirection errors,
+ variable assignment errors for assignments preceding the command name,
+ and so on.
+
+16. The environment passed to executed commands is not sorted. Neither is
+ the output of `set'. This is not strictly Posix.2 behavior, but sh
+ does it this way. Ksh does not. It's not necessary to sort the
+ environment; no program should rely on it being sorted.
+
+17. If the `cd' builtin finds a directory to change to using $CDPATH, the
+ value it assigns to $PWD does not contain any symbolic links, as if
+ `cd -P' had been executed.
+
+18. A non-interactive shell exits with an error status if a variable
+ assignment error occurs when no command name follows the assignment
+ statements. A variable assignment error occurs, for example, when
+ trying to assign a value to a read-only variable.
+
+19. A non-interactive shell exits with an error status if the iteration
+ variable in a for statement or the selection variable in a select
+ statement is a read-only variable.
+
+20. Process substitution is not available.
+
+21. Assignment statements preceding POSIX.2 `special' builtins persist in
+ the shell environment after the builtin completes.
+
+There is other Posix.2 behavior that bash does not implement. Specifically:
+
+1. Assignment statements affect the execution environment of all builtins,
+ not just special ones.
--- /dev/null
+This file is set.def, from which is created set.c.
+It implements the "set" and "unset" builtins in Bash.
+
+Copyright (C) 1987, 1989, 1991 Free Software Foundation, Inc.
+
+This file is part of GNU Bash, the Bourne Again SHell.
+
+Bash is free software; you can redistribute it and/or modify it under
+the terms of the GNU General Public License as published by the Free
+Software Foundation; either version 1, or (at your option) any later
+version.
+
+Bash is distributed in the hope that it will be useful, but WITHOUT ANY
+WARRANTY; without even the implied warranty of MERCHANTABILITY or
+FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+for more details.
+
+You should have received a copy of the GNU General Public License along
+with Bash; see the file COPYING. If not, write to the Free Software
+Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+
+$PRODUCES set.c
+
+#include <stdio.h>
+#include "../shell.h"
+#include "../flags.h"
+
+#include "bashgetopt.h"
+
+extern int interactive;
+extern int noclobber, posixly_correct;
+#if defined (READLINE)
+extern int rl_editing_mode, no_line_editing;
+#endif /* READLINE */
+
+$BUILTIN set
+$FUNCTION set_builtin
+$SHORT_DOC set [--abefhkmnptuvxldBCHP] [-o option] [arg ...]
+ -a Mark variables which are modified or created for export.
+ -b Notify of job termination immediately.
+ -e Exit immediately if a command exits with a non-zero status.
+ -f Disable file name generation (globbing).
+ -h Locate and remember function commands as functions are
+ defined. Function commands are normally looked up when
+ the function is executed.
+ -i Force the shell to be an "interactive" one. Interactive shells
+ always read `~/.bashrc' on startup.
+ -k All keyword arguments are placed in the environment for a
+ command, not just those that precede the command name.
+ -m Job control is enabled.
+ -n Read commands but do not execute them.
+ -o option-name
+ Set the variable corresponding to option-name:
+ allexport same as -a
+ braceexpand same as -B
+#if defined (READLINE)
+ emacs use an emacs-style line editing interface
+#endif /* READLINE */
+ errexit same as -e
+ histexpand same as -H
+ ignoreeof the shell will not exit upon reading EOF
+ interactive-comments
+ allow comments to appear in interactive commands
+ monitor same as -m
+ noclobber disallow redirection to existing files
+ noexec same as -n
+ noglob same as -f
+ nohash same as -d
+ notify save as -b
+ nounset same as -u
+ physical same as -P
+ posix change the behavior of bash where the default
+ operation differs from the 1003.2 standard to
+ match the standard
+ privileged same as -p
+ verbose same as -v
+#if defined (READLINE)
+ vi use a vi-style line editing interface
+#endif /* READLINE */
+ xtrace same as -x
+ -p Turned on whenever the real and effective user ids do not match.
+ Disables processing of the $ENV file and importing of shell
+ functions. Turning this option off causes the effective uid and
+ gid to be set to the real uid and gid.
+ -t Exit after reading and executing one command.
+ -u Treat unset variables as an error when substituting.
+ -v Print shell input lines as they are read.
+ -x Print commands and their arguments as they are executed.
+ -l Save and restore the binding of the NAME in a FOR command.
+ -d Disable the hashing of commands that are looked up for execution.
+ Normally, commands are remembered in a hash table, and once
+ found, do not have to be looked up again.
+#if defined (BRACE_EXPANSION)
+ -B the shell will perform brace expansion
+#endif /* BRACE_EXPANSION */
+#if defined (BANG_HISTORY)
+ -H Enable ! style history substitution. This flag is on
+ by default.
+#endif /* BANG_HISTORY */
+ -C If set, disallow existing regular files to be overwritten
+ by redirection of output.
+ -P If set, do not follow symbolic links when executing commands
+ such as cd which change the current directory.
+
+Using + rather than - causes these flags to be turned off. The
+flags can also be used upon invocation of the shell. The current
+set of flags may be found in $-. The remaining n ARGs are positional
+parameters and are assigned, in order, to $1, $2, .. $n. If no
+ARGs are given, all shell variables are printed.
+$END
+
+/* An a-list used to match long options for set -o to the corresponding
+ option letter. */
+struct {
+ char *name;
+ int letter;
+} o_options[] = {
+ { "allexport", 'a' },
+#if defined (BRACE_EXPANSION)
+ { "braceexpand",'B' },
+#endif
+ { "errexit", 'e' },
+ { "histexpand", 'H' },
+ { "monitor", 'm' },
+ { "noexec", 'n' },
+ { "noglob", 'f' },
+ { "nohash", 'd' },
+#if defined (JOB_CONTROL)
+ { "notify", 'b' },
+#endif /* JOB_CONTROL */
+ {"nounset", 'u' },
+ {"physical", 'P' },
+ {"privileged", 'p' },
+ {"verbose", 'v' },
+ {"xtrace", 'x' },
+ {(char *)NULL, 0},
+};
+
+#define MINUS_O_FORMAT "%-15s\t%s\n"
+
+void
+list_minus_o_opts ()
+{
+ register int i;
+ char *on = "on", *off = "off";
+
+ printf (MINUS_O_FORMAT, "noclobber", (noclobber == 1) ? on : off);
+
+ if (find_variable ("ignoreeof") || find_variable ("IGNOREEOF"))
+ printf (MINUS_O_FORMAT, "ignoreeof", on);
+ else
+ printf (MINUS_O_FORMAT, "ignoreeof", off);
+
+ printf (MINUS_O_FORMAT, "interactive-comments",
+ interactive_comments ? on : off);
+
+ printf (MINUS_O_FORMAT, "posix", posixly_correct ? on : off);
+
+#if defined (READLINE)
+ if (no_line_editing)
+ {
+ printf (MINUS_O_FORMAT, "emacs", off);
+ printf (MINUS_O_FORMAT, "vi", off);
+ }
+ else
+ {
+ /* Magic. This code `knows' how readline handles rl_editing_mode. */
+ printf (MINUS_O_FORMAT, "emacs", (rl_editing_mode == 1) ? on : off);
+ printf (MINUS_O_FORMAT, "vi", (rl_editing_mode == 0) ? on : off);
+ }
+#endif /* READLINE */
+
+ for (i = 0; o_options[i].name; i++)
+ {
+ int *on_or_off, zero = 0;
+
+ on_or_off = find_flag (o_options[i].letter);
+ if (on_or_off == FLAG_UNKNOWN)
+ on_or_off = &zero;
+ printf (MINUS_O_FORMAT, o_options[i].name, (*on_or_off == 1) ? on : off);
+ }
+}
+
+set_minus_o_option (on_or_off, option_name)
+ int on_or_off;
+ char *option_name;
+{
+ int option_char = -1;
+
+ if (STREQ (option_name, "noclobber"))
+ {
+ if (on_or_off == FLAG_ON)
+ bind_variable ("noclobber", "");
+ else
+ unbind_variable ("noclobber");
+ stupidly_hack_special_variables ("noclobber");
+ }
+ else if (STREQ (option_name, "ignoreeof"))
+ {
+ unbind_variable ("ignoreeof");
+ unbind_variable ("IGNOREEOF");
+ if (on_or_off == FLAG_ON)
+ bind_variable ("IGNOREEOF", "10");
+ stupidly_hack_special_variables ("IGNOREEOF");
+ }
+
+#if defined (READLINE)
+ else if ((STREQ (option_name, "emacs")) || (STREQ (option_name, "vi")))
+ {
+ if (on_or_off == FLAG_ON)
+ {
+ rl_variable_bind ("editing-mode", option_name);
+
+ if (interactive)
+ with_input_from_stdin ();
+ no_line_editing = 0;
+ }
+ else
+ {
+ int isemacs = (rl_editing_mode == 1);
+ if ((isemacs && STREQ (option_name, "emacs")) ||
+ (!isemacs && STREQ (option_name, "vi")))
+ {
+ if (interactive)
+ with_input_from_stream (stdin, "stdin");
+ no_line_editing = 1;
+ }
+ else
+ builtin_error ("not in %s editing mode", option_name);
+ }
+ }
+#endif /* READLINE */
+ else if (STREQ (option_name, "interactive-comments"))
+ interactive_comments = (on_or_off == FLAG_ON);
+ else if (STREQ (option_name, "posix"))
+ {
+ posixly_correct = (on_or_off == FLAG_ON);
+ unbind_variable ("POSIXLY_CORRECT");
+ unbind_variable ("POSIX_PEDANTIC");
+ if (on_or_off == FLAG_ON)
+ {
+ bind_variable ("POSIXLY_CORRECT", "");
+ stupidly_hack_special_variables ("POSIXLY_CORRECT");
+ }
+ }
+ else
+ {
+ register int i;
+ for (i = 0; o_options[i].name; i++)
+ {
+ if (STREQ (option_name, o_options[i].name))
+ {
+ option_char = o_options[i].letter;
+ break;
+ }
+ }
+ if (option_char == -1)
+ {
+ builtin_error ("%s: unknown option name", option_name);
+ return (EXECUTION_FAILURE);
+ }
+ if (change_flag (option_char, on_or_off) == FLAG_ERROR)
+ {
+ bad_option (option_name);
+ return (EXECUTION_FAILURE);
+ }
+ }
+ return (EXECUTION_SUCCESS);
+}
+
+/* Set some flags from the word values in the input list. If LIST is empty,
+ then print out the values of the variables instead. If LIST contains
+ non-flags, then set $1 - $9 to the successive words of LIST. */
+set_builtin (list)
+ WORD_LIST *list;
+{
+ int on_or_off, flag_name, force_assignment = 0;
+
+ if (!list)
+ {
+ SHELL_VAR **vars;
+
+ vars = all_shell_variables ();
+ if (vars)
+ {
+ print_var_list (vars);
+ free (vars);
+ }
+
+ vars = all_shell_functions ();
+ if (vars)
+ {
+ print_var_list (vars);
+ free (vars);
+ }
+
+ return (EXECUTION_SUCCESS);
+ }
+
+ /* Check validity of flag arguments. */
+ if (*list->word->word == '-' || *list->word->word == '+')
+ {
+ register char *arg;
+ WORD_LIST *save_list = list;
+
+ while (list && (arg = list->word->word))
+ {
+ char c;
+
+ if (arg[0] != '-' && arg[0] != '+')
+ break;
+
+ /* `-' or `--' signifies end of flag arguments. */
+ if (arg[0] == '-' &&
+ (!arg[1] || (arg[1] == '-' && !arg[2])))
+ break;
+
+ while (c = *++arg)
+ {
+ if (find_flag (c) == FLAG_UNKNOWN && c != 'o')
+ {
+ char s[2];
+ s[0] = c; s[1] = '\0';
+ bad_option (s);
+ if (c == '?')
+ builtin_usage ();
+ return (c == '?' ? EXECUTION_SUCCESS : EXECUTION_FAILURE);
+ }
+ }
+ list = list->next;
+ }
+ list = save_list;
+ }
+
+ /* Do the set command. While the list consists of words starting with
+ '-' or '+' treat them as flags, otherwise, start assigning them to
+ $1 ... $n. */
+ while (list)
+ {
+ char *string = list->word->word;
+
+ /* If the argument is `--' or `-' then signal the end of the list
+ and remember the remaining arguments. */
+ if (string[0] == '-' && (!string[1] || (string[1] == '-' && !string[2])))
+ {
+ list = list->next;
+
+ /* `set --' unsets the positional parameters. */
+ if (string[1] == '-')
+ force_assignment = 1;
+
+ /* Until told differently, the old shell behaviour of
+ `set - [arg ...]' being equivalent to `set +xv [arg ...]'
+ stands. Posix.2 says the behaviour is marked as obsolescent. */
+ else
+ {
+ change_flag ('x', '+');
+ change_flag ('v', '+');
+ }
+
+ break;
+ }
+
+ if ((on_or_off = *string) &&
+ (on_or_off == '-' || on_or_off == '+'))
+ {
+ int i = 1;
+ while (flag_name = string[i++])
+ {
+ if (flag_name == '?')
+ {
+ builtin_usage ();
+ return (EXECUTION_SUCCESS);
+ }
+ else if (flag_name == 'o') /* -+o option-name */
+ {
+ char *option_name;
+ WORD_LIST *opt;
+
+ opt = list->next;
+
+ if (!opt)
+ {
+ list_minus_o_opts ();
+ continue;
+ }
+
+ option_name = opt->word->word;
+
+ if (!option_name || !*option_name || (*option_name == '-'))
+ {
+ list_minus_o_opts ();
+ continue;
+ }
+ list = list->next; /* Skip over option name. */
+
+ if (set_minus_o_option (on_or_off, option_name) != EXECUTION_SUCCESS)
+ return (EXECUTION_FAILURE);
+ }
+ else
+ {
+ if (change_flag (flag_name, on_or_off) == FLAG_ERROR)
+ {
+ char opt[3];
+ opt[0] = on_or_off;
+ opt[1] = flag_name;
+ opt[2] = '\0';
+ bad_option (opt);
+ builtin_usage ();
+ return (EXECUTION_FAILURE);
+ }
+ }
+ }
+ }
+ else
+ {
+ break;
+ }
+ list = list->next;
+ }
+
+ /* Assigning $1 ... $n */
+ if (list || force_assignment)
+ remember_args (list, 1);
+ return (EXECUTION_SUCCESS);
+}
+
+$BUILTIN unset
+$FUNCTION unset_builtin
+$SHORT_DOC unset [-f] [-v] [name ...]
+For each NAME, remove the corresponding variable or function. Given
+the `-v', unset will only act on variables. Given the `-f' flag,
+unset will only act on functions. With neither flag, unset first
+tries to unset a variable, and if that fails, then tries to unset a
+function. Some variables (such as PATH and IFS) cannot be unset; also
+see readonly.
+$END
+
+#define NEXT_VARIABLE() any_failed++; list = list->next; continue;
+
+unset_builtin (list)
+ WORD_LIST *list;
+{
+ int unset_function, unset_variable, unset_array, opt, any_failed;
+ char *name;
+
+ unset_function = unset_variable = unset_array = any_failed = 0;
+
+ reset_internal_getopt ();
+ while ((opt = internal_getopt (list, "fv")) != -1)
+ {
+ switch (opt)
+ {
+ case 'f':
+ unset_function = 1;
+ break;
+ case 'v':
+ unset_variable = 1;
+ break;
+ default:
+ builtin_usage ();
+ return (EXECUTION_FAILURE);
+ }
+ }
+
+ list = loptend;
+
+ if (unset_function && unset_variable)
+ {
+ builtin_error ("cannot simultaneously unset a function and a variable");
+ return (EXECUTION_FAILURE);
+ }
+
+ while (list)
+ {
+ SHELL_VAR *var;
+ int tem;
+#if defined (ARRAY_VARS)
+ char *t;
+#endif
+
+ name = list->word->word;
+
+#if defined (ARRAY_VARS)
+ if (!unset_function && valid_array_reference (name))
+ {
+ t = strchr (name, '[');
+ *t++ = '\0';
+ unset_array++;
+ }
+#endif
+
+ var = unset_function ? find_function (name) : find_variable (name);
+
+ if (var && !unset_function && non_unsettable_p (var))
+ {
+ builtin_error ("%s: cannot unset", name);
+ NEXT_VARIABLE ();
+ }
+
+ /* Posix.2 says that unsetting readonly variables is an error. */
+ if (var && readonly_p (var))
+ {
+ builtin_error ("%s: cannot unset: readonly %s",
+ name, unset_function ? "function" : "variable");
+ NEXT_VARIABLE ();
+ }
+
+ /* Unless the -f option is supplied, the name refers to a variable. */
+#if defined (ARRAY_VARS)
+ if (var && unset_array)
+ {
+ if (array_p (var) == 0)
+ {
+ builtin_error ("%s: not an array variable", name);
+ NEXT_VARIABLE ();
+ }
+ else
+ tem = unbind_array_element (var, t);
+ }
+ else
+#endif /* ARRAY_VARS */
+ tem = makunbound (name, unset_function ? shell_functions : shell_variables);
+
+ /* This is what Posix.2 draft 11+ says. ``If neither -f nor -v
+ is specified, the name refers to a variable; if a variable by
+ that name does not exist, a function by that name, if any,
+ shall be unset.'' */
+ if ((tem == -1) && !unset_function && !unset_variable)
+ tem = makunbound (name, shell_functions);
+
+ if (tem == -1)
+ any_failed++;
+ else if (!unset_function)
+ stupidly_hack_special_variables (name);
+
+ list = list->next;
+ }
+
+ if (any_failed)
+ return (EXECUTION_FAILURE);
+ else
+ return (EXECUTION_SUCCESS);
+}
--- /dev/null
+/* unwind_prot.h - Macros and functions for hacking unwind protection. */
+
+/* Copyright (C) 1993 Free Software Foundation, Inc.
+
+ This file is part of GNU Bash, the Bourne Again SHell.
+
+ Bash is free software; you can redistribute it and/or modify it under
+ the terms of the GNU General Public License as published by the Free
+ Software Foundation; either version 2, or (at your option) any later
+ version.
+
+ Bash is distributed in the hope that it will be useful, but WITHOUT ANY
+ WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ for more details.
+
+ You should have received a copy of the GNU General Public License along
+ with Bash; see the file COPYING. If not, write to the Free Software
+ Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */
+
+#if !defined (_UNWIND_PROT_H)
+#define _UNWIND_PROT_H
+
+/* Run a function without interrupts. */
+extern void begin_unwind_frame ();
+extern void discard_unwind_frame ();
+extern void run_unwind_frame ();
+extern void add_unwind_protect ();
+extern void remove_unwind_protect ();
+extern void run_unwind_protects ();
+extern void unwind_protect_var ();
+
+/* Define for people who like their code to look a certain way. */
+#define end_unwind_frame()
+
+/* How to protect an integer. */
+#define unwind_protect_int(X) unwind_protect_var (&(X), (char *)(X), sizeof (int))
+
+/* How to protect a pointer to a string. */
+#define unwind_protect_string(X) \
+ unwind_protect_var ((int *)&(X), (X), sizeof (char *))
+
+/* How to protect any old pointer. */
+#define unwind_protect_pointer(X) unwind_protect_string (X)
+
+/* How to protect the contents of a jmp_buf. */
+#define unwind_protect_jmp_buf(X) \
+ unwind_protect_var ((int *)(X), (char *)(X), sizeof (procenv_t))
+
+#endif /* _UNWIND_PROT_H */
{
flags = list_opttype == '+' ? &flags_off : &flags_on;
+ /* If you add options here, see whether or not they need to be added to
+ the loop in subst.c:shell_expand_word_list() */
switch (opt)
{
case 'a':
int offset, aflags, wflags;
#if defined (ARRAY_VARS)
int making_array_special, compound_array_assign, simple_array_assign;
+ int var_exists, array_exists, array_subscript_assignment;
#endif
name = savestring (list->word->word);
}
#if defined (ARRAY_VARS)
+ var_exists = array_exists = 0;
compound_array_assign = simple_array_assign = 0;
+ array_subscript_assignment = 0;
subscript_start = (char *)NULL;
if (t = strchr (name, '[')) /* ] */
{
}
subscript_start = t;
*t = '\0';
- making_array_special = 1;
+ making_array_special = 1; /* XXX - should this check offset? */
+ array_subscript_assignment = offset != 0;
}
else
making_array_special = 0;
if (refvar)
var = mkglobal ? find_global_variable (nameref_cell (refvar)) : find_variable (nameref_cell (refvar));
}
-
+
if (var == 0)
var = mkglobal ? find_global_variable (name) : find_variable (name);
+ var_exists = var != 0;
+ array_exists = var && (array_p (var) || assoc_p (var));
+
if (var == 0)
{
#if defined (ARRAY_VARS)
}
#if defined (ARRAY_VARS)
- if ((making_array_special || (flags_on & (att_array|att_assoc)) || array_p (var) || assoc_p (var)) && offset)
+ /* make declare a[2]=foo as similar to a[2]=foo as possible if
+ a is already an array or assoc variable. */
+ if (array_subscript_assignment && array_exists && (flags_on & (att_array|att_assoc)) == 0)
+ simple_array_assign = 1;
+ else if ((making_array_special || (flags_on & (att_array|att_assoc)) || array_p (var) || assoc_p (var)) && offset)
{
int vlen;
vlen = STRLEN (value);
#if 0 /* bash-4.4 */
if (value[0] == '(' && value[vlen-1] == ')' && (shell_compatibility_level <= 43 || (wflags & W_COMPASSIGN)))
#else
+# if 0
if (value[0] == '(' && value[vlen-1] == ')' && (wflags & W_COMPASSIGN))
+# else
+ /* This is the code as in bash-4.3 */
+ if (array_exists == 0 && value[0] == '(' && value[vlen-1] == ')')
+# endif
#endif
compound_array_assign = 1;
else
--- /dev/null
+This file is declare.def, from which is created declare.c.
+It implements the builtins "declare" and "local" in Bash.
+
+Copyright (C) 1987-2014 Free Software Foundation, Inc.
+
+This file is part of GNU Bash, the Bourne Again SHell.
+
+Bash is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+Bash is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with Bash. If not, see <http://www.gnu.org/licenses/>.
+
+$PRODUCES declare.c
+
+$BUILTIN declare
+$FUNCTION declare_builtin
+$SHORT_DOC declare [-aAfFgilnrtux] [-p] [name[=value] ...]
+Set variable values and attributes.
+
+Declare variables and give them attributes. If no NAMEs are given,
+display the attributes and values of all variables.
+
+Options:
+ -f restrict action or display to function names and definitions
+ -F restrict display to function names only (plus line number and
+ source file when debugging)
+ -g create global variables when used in a shell function; otherwise
+ ignored
+ -p display the attributes and value of each NAME
+
+Options which set attributes:
+ -a to make NAMEs indexed arrays (if supported)
+ -A to make NAMEs associative arrays (if supported)
+ -i to make NAMEs have the `integer' attribute
+ -l to convert NAMEs to lower case on assignment
+ -n make NAME a reference to the variable named by its value
+ -r to make NAMEs readonly
+ -t to make NAMEs have the `trace' attribute
+ -u to convert NAMEs to upper case on assignment
+ -x to make NAMEs export
+
+Using `+' instead of `-' turns off the given attribute.
+
+Variables with the integer attribute have arithmetic evaluation (see
+the `let' command) performed when the variable is assigned a value.
+
+When used in a function, `declare' makes NAMEs local, as with the `local'
+command. The `-g' option suppresses this behavior.
+
+Exit Status:
+Returns success unless an invalid option is supplied or a variable
+assignment error occurs.
+$END
+
+$BUILTIN typeset
+$FUNCTION declare_builtin
+$SHORT_DOC typeset [-aAfFgilrtux] [-p] name[=value] ...
+Set variable values and attributes.
+
+Obsolete. See `help declare'.
+$END
+
+#include <config.h>
+
+#if defined (HAVE_UNISTD_H)
+# ifdef _MINIX
+# include <sys/types.h>
+# endif
+# include <unistd.h>
+#endif
+
+#include <stdio.h>
+
+#include "../bashansi.h"
+#include "../bashintl.h"
+
+#include "../shell.h"
+#include "../flags.h"
+#include "common.h"
+#include "builtext.h"
+#include "bashgetopt.h"
+
+extern int array_needs_making;
+extern int posixly_correct;
+
+static int declare_internal __P((register WORD_LIST *, int));
+
+/* Declare or change variable attributes. */
+int
+declare_builtin (list)
+ register WORD_LIST *list;
+{
+ return (declare_internal (list, 0));
+}
+
+$BUILTIN local
+$FUNCTION local_builtin
+$SHORT_DOC local [option] name[=value] ...
+Define local variables.
+
+Create a local variable called NAME, and give it VALUE. OPTION can
+be any option accepted by `declare'.
+
+Local variables can only be used within a function; they are visible
+only to the function where they are defined and its children.
+
+Exit Status:
+Returns success unless an invalid option is supplied, a variable
+assignment error occurs, or the shell is not executing a function.
+$END
+int
+local_builtin (list)
+ register WORD_LIST *list;
+{
+ if (variable_context)
+ return (declare_internal (list, 1));
+ else
+ {
+ builtin_error (_("can only be used in a function"));
+ return (EXECUTION_FAILURE);
+ }
+}
+
+#if defined (ARRAY_VARS)
+# define DECLARE_OPTS "+acfgilnprtuxAF"
+#else
+# define DECLARE_OPTS "+cfgilnprtuxF"
+#endif
+
+/* The workhorse function. */
+static int
+declare_internal (list, local_var)
+ register WORD_LIST *list;
+ int local_var;
+{
+ int flags_on, flags_off, *flags;
+ int any_failed, assign_error, pflag, nodefs, opt, mkglobal, onref, offref;
+ char *t, *subscript_start;
+ SHELL_VAR *var, *refvar, *v;
+ FUNCTION_DEF *shell_fn;
+
+ flags_on = flags_off = any_failed = assign_error = pflag = nodefs = mkglobal = 0;
+ refvar = (SHELL_VAR *)NULL;
+ reset_internal_getopt ();
+ while ((opt = internal_getopt (list, DECLARE_OPTS)) != -1)
+ {
+ flags = list_opttype == '+' ? &flags_off : &flags_on;
+
+ /* If you add options here, see whether or not they need to be added to
+ the loop in subst.c:shell_expand_word_list() */
+ switch (opt)
+ {
+ case 'a':
+#if defined (ARRAY_VARS)
+ *flags |= att_array;
+ break;
+#else
+ builtin_usage ();
+ return (EX_USAGE);
+#endif
+ case 'A':
+#if defined (ARRAY_VARS)
+ *flags |= att_assoc;
+ break;
+#else
+ builtin_usage ();
+ return (EX_USAGE);
+#endif
+ case 'p':
+ if (local_var == 0)
+ pflag++;
+ break;
+ case 'F':
+ nodefs++;
+ *flags |= att_function;
+ break;
+ case 'f':
+ *flags |= att_function;
+ break;
+ case 'g':
+ if (flags == &flags_on)
+ mkglobal = 1;
+ break;
+ case 'i':
+ *flags |= att_integer;
+ break;
+ case 'n':
+ *flags |= att_nameref;
+ break;
+ case 'r':
+ *flags |= att_readonly;
+ break;
+ case 't':
+ *flags |= att_trace;
+ break;
+ case 'x':
+ *flags |= att_exported;
+ array_needs_making = 1;
+ break;
+#if defined (CASEMOD_ATTRS)
+# if defined (CASEMOD_CAPCASE)
+ case 'c':
+ *flags |= att_capcase;
+ if (flags == &flags_on)
+ flags_off |= att_uppercase|att_lowercase;
+ break;
+# endif
+ case 'l':
+ *flags |= att_lowercase;
+ if (flags == &flags_on)
+ flags_off |= att_capcase|att_uppercase;
+ break;
+ case 'u':
+ *flags |= att_uppercase;
+ if (flags == &flags_on)
+ flags_off |= att_capcase|att_lowercase;
+ break;
+#endif /* CASEMOD_ATTRS */
+ default:
+ builtin_usage ();
+ return (EX_USAGE);
+ }
+ }
+
+ list = loptend;
+
+ /* If there are no more arguments left, then we just want to show
+ some variables. */
+ if (list == 0) /* declare -[aAfFirtx] */
+ {
+ /* Show local variables defined at this context level if this is
+ the `local' builtin. */
+ if (local_var)
+ {
+ register SHELL_VAR **vlist;
+ register int i;
+
+ vlist = all_local_variables ();
+
+ if (vlist)
+ {
+ for (i = 0; vlist[i]; i++)
+ print_assignment (vlist[i]);
+
+ free (vlist);
+ }
+ }
+ else if (pflag && (flags_on == 0 || flags_on == att_function))
+ show_all_var_attributes (flags_on == 0, nodefs);
+ else if (flags_on == 0)
+ return (set_builtin ((WORD_LIST *)NULL));
+ else
+ set_or_show_attributes ((WORD_LIST *)NULL, flags_on, nodefs);
+
+ return (sh_chkwrite (EXECUTION_SUCCESS));
+ }
+
+ if (pflag) /* declare -p [-aAfFirtx] name [name...] */
+ {
+ for (any_failed = 0; list; list = list->next)
+ {
+ if (flags_on & att_function)
+ pflag = show_func_attributes (list->word->word, nodefs);
+ else
+ pflag = show_name_attributes (list->word->word, nodefs);
+ if (pflag)
+ {
+ sh_notfound (list->word->word);
+ any_failed++;
+ }
+ }
+ return (sh_chkwrite (any_failed ? EXECUTION_FAILURE : EXECUTION_SUCCESS));
+ }
+
+#define NEXT_VARIABLE() free (name); list = list->next; continue
+
+ /* There are arguments left, so we are making variables. */
+ while (list) /* declare [-aAfFirx] name [name ...] */
+ {
+ char *value, *name;
+ int offset, aflags, wflags;
+#if defined (ARRAY_VARS)
+ int making_array_special, compound_array_assign, simple_array_assign;
+ int var_exists, array_exists, array_subscript_assignment;
+#endif
+
+ name = savestring (list->word->word);
+ wflags = list->word->flags;
+ offset = assignment (name, 0);
+ aflags = 0;
+
+ if (offset) /* declare [-aAfFirx] name=value */
+ {
+ name[offset] = '\0';
+ value = name + offset + 1;
+ if (name[offset - 1] == '+')
+ {
+ aflags |= ASS_APPEND;
+ name[offset - 1] = '\0';
+ }
+ }
+ else
+ value = "";
+
+ /* Do some lexical error checking on the LHS and RHS of the assignment
+ that is specific to nameref variables. */
+ if (flags_on & att_nameref)
+ {
+#if defined (ARRAY_VARIABLES)
+ if (valid_array_reference (name))
+ {
+ builtin_error (_("%s: reference variable cannot be an array"), name);
+ assign_error++;
+ NEXT_VARIABLE ();
+ }
+ else
+#endif
+ /* disallow self references at global scope */
+ if (STREQ (name, value) && variable_context == 0)
+ {
+ builtin_error (_("%s: nameref variable self references not allowed"), name);
+ assign_error++;
+ NEXT_VARIABLE ();
+ }
+ }
+
+#if defined (ARRAY_VARS)
+ var_exists = array_exists = 0;
+ compound_array_assign = simple_array_assign = 0;
+ array_subscript_assignment = 0;
+ subscript_start = (char *)NULL;
+ if (t = strchr (name, '[')) /* ] */
+ {
+ /* If offset != 0 we have already validated any array reference */
+ if (offset == 0 && valid_array_reference (name) == 0)
+ {
+ sh_invalidid (name);
+ assign_error++;
+ NEXT_VARIABLE ();
+ }
+ subscript_start = t;
+ *t = '\0';
+ making_array_special = 1; /* XXX - should this check offset? */
+ array_subscript_assignment = offset != 0;
+ }
+ else
+ making_array_special = 0;
+#endif
+
+ /* If we're in posix mode or not looking for a shell function (since
+ shell function names don't have to be valid identifiers when the
+ shell's not in posix mode), check whether or not the argument is a
+ valid, well-formed shell identifier. */
+ if ((posixly_correct || (flags_on & att_function) == 0) && legal_identifier (name) == 0)
+ {
+ sh_invalidid (name);
+ assign_error++;
+ NEXT_VARIABLE ();
+ }
+
+ /* If VARIABLE_CONTEXT has a non-zero value, then we are executing
+ inside of a function. This means we should make local variables,
+ not global ones. */
+
+ /* XXX - this has consequences when we're making a local copy of a
+ variable that was in the temporary environment. Watch out
+ for this. */
+ refvar = (SHELL_VAR *)NULL;
+ if (variable_context && mkglobal == 0 && ((flags_on & att_function) == 0))
+ {
+#if defined (ARRAY_VARS)
+ if (flags_on & att_assoc)
+ var = make_local_assoc_variable (name);
+ else if ((flags_on & att_array) || making_array_special)
+ var = make_local_array_variable (name, making_array_special);
+ else
+#endif
+ var = make_local_variable (name); /* sets att_invisible for new vars */
+ if (var == 0)
+ {
+ any_failed++;
+ NEXT_VARIABLE ();
+ }
+ }
+ else
+ var = (SHELL_VAR *)NULL;
+
+ /* If we are declaring a function, then complain about it in some way.
+ We don't let people make functions by saying `typeset -f foo=bar'. */
+
+ /* There should be a way, however, to let people look at a particular
+ function definition by saying `typeset -f foo'. */
+
+ if (flags_on & att_function)
+ {
+ if (offset) /* declare -f [-rix] foo=bar */
+ {
+ builtin_error (_("cannot use `-f' to make functions"));
+ free (name);
+ return (EXECUTION_FAILURE);
+ }
+ else /* declare -f [-rx] name [name...] */
+ {
+ var = find_function (name);
+
+ if (var)
+ {
+ if (readonly_p (var) && (flags_off & att_readonly))
+ {
+ builtin_error (_("%s: readonly function"), name);
+ any_failed++;
+ NEXT_VARIABLE ();
+ }
+
+ /* declare -[Ff] name [name...] */
+ if (flags_on == att_function && flags_off == 0)
+ {
+#if defined (DEBUGGER)
+ if (nodefs && debugging_mode)
+ {
+ shell_fn = find_function_def (var->name);
+ if (shell_fn)
+ printf ("%s %d %s\n", var->name, shell_fn->line, shell_fn->source_file);
+ else
+ printf ("%s\n", var->name);
+ }
+ else
+#endif /* DEBUGGER */
+ {
+ t = nodefs ? var->name
+ : named_function_string (name, function_cell (var), FUNC_MULTILINE|FUNC_EXTERNAL);
+ printf ("%s\n", t);
+ any_failed = sh_chkwrite (any_failed);
+ }
+ }
+ else /* declare -[fF] -[rx] name [name...] */
+ {
+ VSETATTR (var, flags_on);
+ VUNSETATTR (var, flags_off);
+ }
+ }
+ else
+ any_failed++;
+ NEXT_VARIABLE ();
+ }
+ }
+ else /* declare -[aAirx] name [name...] */
+ {
+ /* Non-null if we just created or fetched a local variable. */
+ /* Here's what ksh93 seems to do. If we are modifying an existing
+ nameref variable, we don't follow the nameref chain past the last
+ nameref, and we set the nameref variable's value so future
+ references to that variable will return the value of the variable
+ we're assigning right now. */
+ if (var == 0 && (flags_on & att_nameref))
+ {
+ /* See if we are trying to modify an existing nameref variable */
+ var = mkglobal ? find_global_variable_last_nameref (name) : find_variable_last_nameref (name);
+ if (var && nameref_p (var) == 0)
+ var = 0;
+ }
+ /* However, if we're turning off the nameref attribute on an existing
+ nameref variable, we first follow the nameref chain to the end,
+ modify the value of the variable this nameref variable references,
+ *CHANGING ITS VALUE AS A SIDE EFFECT* then turn off the nameref
+ flag *LEAVING THE NAMEREF VARIABLE'S VALUE UNCHANGED* */
+ else if (var == 0 && (flags_off & att_nameref))
+ {
+ /* See if we are trying to modify an existing nameref variable */
+ refvar = mkglobal ? find_global_variable_last_nameref (name) : find_variable_last_nameref (name);
+ if (refvar && nameref_p (refvar) == 0)
+ refvar = 0;
+ if (refvar)
+ var = mkglobal ? find_global_variable (nameref_cell (refvar)) : find_variable (nameref_cell (refvar));
+ }
+
+ var_exists = var != 0;
+ array_exists = var && (array_p (var) || assoc_p (var));
+
+ if (var == 0)
+ var = mkglobal ? find_global_variable (name) : find_variable (name);
+
+ if (var == 0)
+ {
+#if defined (ARRAY_VARS)
+ if (flags_on & att_assoc)
+ {
+ var = make_new_assoc_variable (name);
+ if (offset == 0 && no_invisible_vars == 0)
+ VSETATTR (var, att_invisible);
+ }
+ else if ((flags_on & att_array) || making_array_special)
+ {
+ var = make_new_array_variable (name);
+ if (offset == 0 && no_invisible_vars == 0)
+ VSETATTR (var, att_invisible);
+ }
+ else
+#endif
+ if (offset)
+ var = mkglobal ? bind_global_variable (name, "", 0) : bind_variable (name, "", 0);
+ else
+ {
+ var = mkglobal ? bind_global_variable (name, (char *)NULL, 0) : bind_variable (name, (char *)NULL, 0);
+ if (no_invisible_vars == 0)
+ VSETATTR (var, att_invisible);
+ }
+ }
+ /* Can't take an existing array variable and make it a nameref */
+ else if ((array_p (var) || assoc_p (var)) && (flags_on & att_nameref))
+ {
+ builtin_error (_("%s: reference variable cannot be an array"), name);
+ assign_error++;
+ NEXT_VARIABLE ();
+ }
+ else if (flags_on & att_nameref)
+ {
+ /* ksh93 compat: turning on nameref attribute turns off -ilu */
+ VUNSETATTR (var, att_integer|att_uppercase|att_lowercase|att_capcase);
+ }
+
+ /* Cannot use declare +r to turn off readonly attribute. */
+ if (readonly_p (var) && (flags_off & att_readonly))
+ {
+ sh_readonly (name);
+ any_failed++;
+ NEXT_VARIABLE ();
+ }
+
+ /* Cannot use declare to assign value to readonly or noassign
+ variable. */
+ if ((readonly_p (var) || noassign_p (var)) && offset)
+ {
+ if (readonly_p (var))
+ sh_readonly (name);
+ assign_error++;
+ NEXT_VARIABLE ();
+ }
+
+#if defined (ARRAY_VARS)
+ /* make declare a[2]=foo as similar to a[2]=foo as possible if
+ a is already an array or assoc variable. */
+ if (array_subscript_assignment && array_exists && (flags_on & (att_array|att_assoc)) == 0)
+ simple_array_assign = 1;
+ else if ((making_array_special || (flags_on & (att_array|att_assoc)) || array_p (var) || assoc_p (var)) && offset)
+ {
+ int vlen;
+ vlen = STRLEN (value);
+/*itrace("declare_builtin: name = %s value = %s flags = %d", name, value, wflags);*/
+#if 0 /* bash-4.4 */
+ if (value[0] == '(' && value[vlen-1] == ')' && (shell_compatibility_level <= 43 || (wflags & W_COMPASSIGN)))
+#else
+# if 0
+ if (value[0] == '(' && value[vlen-1] == ')' && (wflags & W_COMPASSIGN))
+# else
+ /* This is the code as in bash-4.3 */
+ if (array_exists == 0 && value[0] == '(' && value[vlen-1] == ')')
+# endif
+#endif
+ compound_array_assign = 1;
+ else
+ simple_array_assign = 1;
+ }
+
+ /* Cannot use declare +a name or declare +A name to remove an
+ array variable. */
+ if (((flags_off & att_array) && array_p (var)) || ((flags_off & att_assoc) && assoc_p (var)))
+ {
+ builtin_error (_("%s: cannot destroy array variables in this way"), name);
+ any_failed++;
+ NEXT_VARIABLE ();
+ }
+
+ if ((flags_on & att_array) && assoc_p (var))
+ {
+ builtin_error (_("%s: cannot convert associative to indexed array"), name);
+ any_failed++;
+ NEXT_VARIABLE ();
+ }
+ if ((flags_on & att_assoc) && array_p (var))
+ {
+ builtin_error (_("%s: cannot convert indexed to associative array"), name);
+ any_failed++;
+ NEXT_VARIABLE ();
+ }
+
+ /* declare -A name[[n]] makes name an associative array variable. */
+ if (flags_on & att_assoc)
+ {
+ if (assoc_p (var) == 0)
+ var = convert_var_to_assoc (var);
+ }
+ /* declare -a name[[n]] or declare name[n] makes name an indexed
+ array variable. */
+ else if ((making_array_special || (flags_on & att_array)) && array_p (var) == 0 && assoc_p (var) == 0)
+ var = convert_var_to_array (var);
+#endif /* ARRAY_VARS */
+
+ /* XXX - we note that we are turning on nameref attribute and defer
+ setting it until the assignment has been made so we don't do an
+ inadvertent nameref lookup. Might have to do the same thing for
+ flags_off&att_nameref. */
+ /* XXX - ksh93 makes it an error to set a readonly nameref variable
+ using a single typeset command. */
+ onref = (flags_on & att_nameref);
+ flags_on &= ~att_nameref;
+#if defined (ARRAY_VARS)
+ if (array_p (var) || assoc_p (var)
+ || (offset && compound_array_assign)
+ || simple_array_assign)
+ onref = 0; /* array variables may not be namerefs */
+#endif
+
+ /* ksh93 seems to do this */
+ offref = (flags_off & att_nameref);
+ flags_off &= ~att_nameref;
+
+ VSETATTR (var, flags_on);
+ VUNSETATTR (var, flags_off);
+
+#if defined (ARRAY_VARS)
+ aflags |= ASS_FORCE;
+ if (offset && compound_array_assign)
+ assign_array_var_from_string (var, value, aflags);
+ else if (simple_array_assign && subscript_start)
+ {
+ /* declare [-aA] name[N]=value */
+ *subscript_start = '['; /* ] */
+ var = assign_array_element (name, value, 0); /* XXX - not aflags */
+ *subscript_start = '\0';
+ if (var == 0) /* some kind of assignment error */
+ {
+ assign_error++;
+ flags_on |= onref;
+ flags_off |= offref;
+ NEXT_VARIABLE ();
+ }
+ }
+ else if (simple_array_assign)
+ {
+ /* let bind_{array,assoc}_variable take care of this. */
+ if (assoc_p (var))
+ bind_assoc_variable (var, name, savestring ("0"), value, aflags);
+ else
+ bind_array_variable (name, 0, value, aflags);
+ }
+ else
+#endif
+ /* bind_variable_value duplicates the essential internals of
+ bind_variable() */
+ if (offset)
+ {
+ if (onref)
+ aflags |= ASS_NAMEREF;
+ v = bind_variable_value (var, value, aflags);
+ if (v == 0 && onref)
+ {
+ sh_invalidid (value);
+ assign_error++;
+ /* XXX - unset this variable? or leave it as normal var? */
+ delete_var (var->name, mkglobal ? global_variables : shell_variables);
+ NEXT_VARIABLE ();
+ }
+ }
+
+ /* If we found this variable in the temporary environment, as with
+ `var=value declare -x var', make sure it is treated identically
+ to `var=value export var'. Do the same for `declare -r' and
+ `readonly'. Preserve the attributes, except for att_tempvar. */
+ /* XXX -- should this create a variable in the global scope, or
+ modify the local variable flags? ksh93 has it modify the
+ global scope.
+ Need to handle case like in set_var_attribute where a temporary
+ variable is in the same table as the function local vars. */
+ if ((flags_on & (att_exported|att_readonly)) && tempvar_p (var))
+ {
+ SHELL_VAR *tv;
+ char *tvalue;
+
+ tv = find_tempenv_variable (var->name);
+ if (tv)
+ {
+ tvalue = var_isset (var) ? savestring (value_cell (var)) : savestring ("");
+ tv = bind_variable (var->name, tvalue, 0);
+ tv->attributes |= var->attributes & ~att_tempvar;
+ if (tv->context > 0)
+ VSETATTR (tv, att_propagate);
+ free (tvalue);
+ }
+ VSETATTR (var, att_propagate);
+ }
+ }
+
+ /* Turn on nameref attribute we deferred above. */
+ /* XXX - should we turn on the noassign attribute for consistency with
+ ksh93 when we turn on the nameref attribute? */
+ VSETATTR (var, onref);
+ flags_on |= onref;
+ VUNSETATTR (var, offref);
+ flags_off |= offref;
+ /* Yuck. ksh93 compatibility */
+ if (refvar)
+ VUNSETATTR (refvar, flags_off);
+
+ stupidly_hack_special_variables (name);
+
+ NEXT_VARIABLE ();
+ }
+
+ return (assign_error ? EX_BADASSIGN
+ : ((any_failed == 0) ? EXECUTION_SUCCESS
+ : EXECUTION_FAILURE));
+}
#define W_ARRAYIND 0x1000000 /* word is an array index being expanded */
#define W_ASSNGLOBAL 0x2000000 /* word is a global assignment to declare (declare/typeset -g) */
#define W_NOBRACE 0x4000000 /* Don't perform brace expansion */
-#define W_ASSIGNINT 0x8000000 /* word is an integer assignment to declare */
/* Possible values for subshell_environment */
#define SUBSHELL_ASYNC 0x01 /* subshell caused by `command &' */
--- /dev/null
+# This file is a shell script that caches the results of configure
+# tests for CYGWIN32 so they don't need to be done when cross-compiling.
+
+# AC_FUNC_GETPGRP should also define GETPGRP_VOID
+ac_cv_func_getpgrp_void=${ac_cv_func_getpgrp_void='yes'}
+# AC_FUNC_SETVBUF_REVERSED should not define anything else
+ac_cv_func_setvbuf_reversed=${ac_cv_func_setvbuf_reversed='no'}
+# on CYGWIN32, system calls do not restart
+ac_cv_sys_restartable_syscalls=${ac_cv_sys_restartable_syscalls='no'}
+bash_cv_sys_restartable_syscalls=${bash_cv_sys_restartable_syscalls='no'}
+
+# these may be necessary, but they are currently commented out
+#ac_cv_c_bigendian=${ac_cv_c_bigendian='no'}
+ac_cv_sizeof_char_p=${ac_cv_sizeof_char_p='4'}
+ac_cv_sizeof_int=${ac_cv_sizeof_int='4'}
+ac_cv_sizeof_long=${ac_cv_sizeof_long='4'}
+ac_cv_sizeof_double=${ac_cv_sizeof_double='8'}
+
+bash_cv_dup2_broken=${bash_cv_dup2_broken='no'}
+bash_cv_pgrp_pipe=${bash_cv_pgrp_pipe='no'}
+bash_cv_type_rlimit=${bash_cv_type_rlimit='long'}
+bash_cv_decl_under_sys_siglist=${bash_cv_decl_under_sys_siglist='no'}
+bash_cv_under_sys_siglist=${bash_cv_under_sys_siglist='no'}
+bash_cv_sys_siglist=${bash_cv_sys_siglist='no'}
+bash_cv_opendir_not_robust=${bash_cv_opendir_not_robust='no'}
+bash_cv_getenv_redef=${bash_cv_getenv_redef='yes'}
+bash_cv_printf_declared=${bash_cv_printf_declared='yes'}
+bash_cv_ulimit_maxfds=${bash_cv_ulimit_maxfds='no'}
+bash_cv_getcwd_calls_popen=${bash_cv_getcwd_calls_popen='no'}
+bash_cv_must_reinstall_sighandlers=${bash_cv_must_reinstall_sighandlers='no'}
+bash_cv_job_control_missing=${bash_cv_job_control_missing='present'}
+bash_cv_sys_named_pipes=${bash_cv_sys_named_pipes='missing'}
+bash_cv_func_sigsetjmp=${bash_cv_func_sigsetjmp='missing'}
+bash_cv_mail_dir=${bash_cv_mail_dir='unknown'}
+bash_cv_func_strcoll_broken=${bash_cv_func_strcoll_broken='no'}
+
+bash_cv_type_int32_t=${bash_cv_type_int32_t='int'}
+bash_cv_type_u_int32_t=${bash_cv_type_u_int32_t='int'}
+
+ac_cv_type_bits64_t=${ac_cv_type_bits64_t='no'}
+
+# end of cross-build/cygwin32.cache
--- /dev/null
+This is the Bash FAQ, version 3.24, for Bash version 2.05b.
+
+This document contains a set of frequently-asked questions concerning
+Bash, the GNU Bourne-Again Shell. Bash is a freely-available command
+interpreter with advanced features for both interactive use and shell
+programming.
+
+Another good source of basic information about shells is the collection
+of FAQ articles periodically posted to comp.unix.shell.
+
+Questions and comments concerning this document should be sent to
+chet@po.cwru.edu.
+
+This document is available for anonymous FTP with the URL
+
+ftp://ftp.cwru.edu/pub/bash/FAQ
+
+The Bash home page is http://cnswww.cns.cwru.edu/~chet/bash/bashtop.html
+
+----------
+Contents:
+
+Section A: The Basics
+
+A1) What is it?
+A2) What's the latest version?
+A3) Where can I get it?
+A4) On what machines will bash run?
+A5) Will bash run on operating systems other than Unix?
+A6) How can I build bash with gcc?
+A7) How can I make bash my login shell?
+A8) I just changed my login shell to bash, and now I can't FTP into my
+ machine. Why not?
+A9) What's the `POSIX 1003.2 standard'?
+A10) What is the bash `posix mode'?
+
+Section B: The latest version
+
+B1) What's new in version 2.05b?
+B2) Are there any user-visible incompatibilities between bash-2.05b and
+ bash-1.14.7?
+
+Section C: Differences from other Unix shells
+
+C1) How does bash differ from sh, the Bourne shell?
+C2) How does bash differ from the Korn shell, version ksh88?
+C3) Which new features in ksh-93 are not in bash, and which are?
+
+Section D: Why does bash do some things differently than other Unix shells?
+
+D1) Why does bash run a different version of `command' than
+ `which command' says it will?
+D2) Why doesn't bash treat brace expansions exactly like csh?
+D3) Why doesn't bash have csh variable modifiers?
+D4) How can I make my csh aliases work when I convert to bash?
+D5) How can I pipe standard output and standard error from one command to
+ another, like csh does with `|&'?
+D6) Now that I've converted from ksh to bash, are there equivalents to
+ ksh features like autoloaded functions and the `whence' command?
+
+Section E: Why does bash do certain things the way it does?
+
+E1) Why is the bash builtin `test' slightly different from /bin/test?
+E2) Why does bash sometimes say `Broken pipe'?
+E3) When I have terminal escape sequences in my prompt, why does bash
+ wrap lines at the wrong column?
+E4) If I pipe the output of a command into `read variable', why doesn't
+ the output show up in $variable when the read command finishes?
+E5) I have a bunch of shell scripts that use backslash-escaped characters
+ in arguments to `echo'. Bash doesn't interpret these characters. Why
+ not, and how can I make it understand them?
+E6) Why doesn't a while or for loop get suspended when I type ^Z?
+E7) What about empty for loops in Makefiles?
+E8) Why does the arithmetic evaluation code complain about `08'?
+E9) Why does the pattern matching expression [A-Z]* match files beginning
+ with every letter except `z'?
+E10) Why does `cd //' leave $PWD as `//'?
+E11) If I resize my xterm while another program is running, why doesn't bash
+ notice the change?
+
+Section F: Things to watch out for on certain Unix versions
+
+F1) Why can't I use command line editing in my `cmdtool'?
+F2) I built bash on Solaris 2. Why do globbing expansions and filename
+ completion chop off the first few characters of each filename?
+F3) Why does bash dump core after I interrupt username completion or
+ `~user' tilde expansion on a machine running NIS?
+F4) I'm running SVR4.2. Why is the line erased every time I type `@'?
+F5) Why does bash report syntax errors when my C News scripts use a
+ redirection before a subshell command?
+F6) Why can't I use vi-mode editing on Red Hat Linux 6.1?
+F7) Why do bash-2.05a and bash-2.05b fail to compile `printf.def' on
+ HP/UX 11.x?
+
+Section G: How can I get bash to do certain common things?
+
+G1) How can I get bash to read and display eight-bit characters?
+G2) How do I write a function `x' to replace builtin command `x', but
+ still invoke the command from within the function?
+G3) How can I find the value of a shell variable whose name is the value
+ of another shell variable?
+G4) How can I make the bash `time' reserved word print timing output that
+ looks like the output from my system's /usr/bin/time?
+G5) How do I get the current directory into my prompt?
+G6) How can I rename "*.foo" to "*.bar"?
+G7) How can I translate a filename from uppercase to lowercase?
+G8) How can I write a filename expansion (globbing) pattern that will match
+ all files in the current directory except "." and ".."?
+
+Section H: Where do I go from here?
+
+H1) How do I report bugs in bash, and where should I look for fixes and
+ advice?
+H2) What kind of bash documentation is there?
+H3) What's coming in future versions?
+H4) What's on the bash `wish list'?
+H5) When will the next release appear?
+
+----------
+Section A: The Basics
+
+A1) What is it?
+
+Bash is a Unix command interpreter (shell). It is an implementation of
+the Posix 1003.2 shell standard, and resembles the Korn and System V
+shells.
+
+Bash contains a number of enhancements over those shells, both
+for interactive use and shell programming. Features geared
+toward interactive use include command line editing, command
+history, job control, aliases, and prompt expansion. Programming
+features include additional variable expansions, shell
+arithmetic, and a number of variables and options to control
+shell behavior.
+
+Bash was originally written by Brian Fox of the Free Software
+Foundation. The current developer and maintainer is Chet Ramey
+of Case Western Reserve University.
+
+A2) What's the latest version?
+
+The latest version is 2.05b, first made available on Wednesday, 17
+July, 2002.
+
+A3) Where can I get it?
+
+Bash is the GNU project's shell, and so is available from the
+master GNU archive site, ftp.gnu.org, and its mirrors. The
+latest version is also available for FTP from ftp.cwru.edu.
+The following URLs tell how to get version 2.05b:
+
+ftp://ftp.gnu.org/pub/gnu/bash/bash-2.05b.tar.gz
+ftp://ftp.cwru.edu/pub/bash/bash-2.05b.tar.gz
+
+Formatted versions of the documentation are available with the URLs:
+
+ftp://ftp.gnu.org/pub/gnu/bash/bash-doc-2.05b.tar.gz
+ftp://ftp.cwru.edu/pub/bash/bash-doc-2.05b.tar.gz
+
+A4) On what machines will bash run?
+
+Bash has been ported to nearly every version of UNIX. All you
+should have to do to build it on a machine for which a port
+exists is to type `configure' and then `make'. The build process
+will attempt to discover the version of UNIX you have and tailor
+itself accordingly, using a script created by GNU autoconf.
+
+More information appears in the file `INSTALL' in the distribution.
+
+The Bash web page (http://cnswww.cns.cwru.edu/~chet/bash/bashtop.html)
+explains how to obtain binary versions of bash for most of the major
+commercial Unix systems.
+
+A5) Will bash run on operating systems other than Unix?
+
+Configuration specifics for Unix-like systems such as QNX and
+LynxOS are included in the distribution. Bash-2.05 and later
+versions should compile and run on Minix 2.0 (patches were
+contributed), but I don't believe anyone has built bash-2.x on
+earlier Minix versions yet.
+
+Bash has been ported to versions of Windows implementing the Win32
+programming interface. This includes Windows 95 and Windows NT.
+The port was done by Cygnus Solutions as part of their CYGWIN
+project. For more information about the project, look at the URLs
+
+http://www.cygwin.com/
+http://sourceware.cygnus.com/cygwin
+
+Cygnus originally ported bash-1.14.7, and that port was part of their
+early GNU-Win32 (the original name) releases. Cygnus has also done a
+port of bash-2.05 to the CYGWIN environment, and it is available as
+part of their current release.
+
+Bash-2.05b should require no local Cygnus changes to build and run under
+CYGWIN.
+
+The Cygnus port works only on Intel machines. There is a port of bash
+(I don't know which version) to the alpha/NT environment available from
+
+ftp://ftp.gnustep.org//pub/win32/bash-alpha-nt-1.01.tar.gz
+
+DJ Delorie has a port of bash-2.x which runs under MS-DOS, as part
+of the DJGPP project. For more information on the project, see
+
+http://www.delorie.com/djgpp/
+
+I have been told that the original DJGPP port was done by Daisuke Aoyama.
+
+Mark Elbrecht <snowball3@bigfoot.com> has sent me notice that bash-2.04
+is available for DJGPP V2. The files are available as:
+
+ftp://ftp.simtel.net/pub/simtelnet/gnu/djgpp/v2gnu/bsh204b.zip binary
+ftp://ftp.simtel.net/pub/simtelnet/gnu/djgpp/v2gnu/bsh204d.zip documentation
+ftp://ftp.simtel.net/pub/simtelnet/gnu/djgpp/v2gnu/bsh204s.zip source
+
+Mark has begun to work with bash-2.05, but I don't know the status.
+
+Ports of bash-1.12 and bash-2.0 are available for OS/2 from
+
+ftp://hobbes.nmsu.edu/pub/os2/util/shell/bash_112.zip
+ftp://hobbes.nmsu.edu/pub/os2/util/shell/bash-2.0(253).zip
+
+I haven't looked at either, but the second appears to be a binary-only
+distribution. Beware.
+
+I have received word that Bash (I'm not sure which version, but I
+believe that it's at least bash-2.02.1) is the standard shell on
+BeOS.
+
+A6) How can I build bash with gcc?
+
+Bash configures to use gcc by default if it is available. Read the
+file INSTALL in the distribution for more information.
+
+A7) How can I make bash my login shell?
+
+Some machines let you use `chsh' to change your login shell. Other
+systems use `passwd -s' or `passwd -e'. If one of these works for
+you, that's all you need. Note that many systems require the full
+pathname to a shell to appear in /etc/shells before you can make it
+your login shell. For this, you may need the assistance of your
+friendly local system administrator.
+
+If you cannot do this, you can still use bash as your login shell, but
+you need to perform some tricks. The basic idea is to add a command
+to your login shell's startup file to replace your login shell with
+bash.
+
+For example, if your login shell is csh or tcsh, and you have installed
+bash in /usr/gnu/bin/bash, add the following line to ~/.login:
+
+ if ( -f /usr/gnu/bin/bash ) exec /usr/gnu/bin/bash --login
+
+(the `--login' tells bash that it is a login shell).
+
+It's not a good idea to put this command into ~/.cshrc, because every
+csh you run without the `-f' option, even ones started to run csh scripts,
+reads that file. If you must put the command in ~/.cshrc, use something
+like
+
+ if ( $?prompt ) exec /usr/gnu/bin/bash --login
+
+to ensure that bash is exec'd only when the csh is interactive.
+
+If your login shell is sh or ksh, you have to do two things.
+
+First, create an empty file in your home directory named `.bash_profile'.
+The existence of this file will prevent the exec'd bash from trying to
+read ~/.profile, and re-execing itself over and over again. ~/.bash_profile
+is the first file bash tries to read initialization commands from when
+it is invoked as a login shell.
+
+Next, add a line similar to the above to ~/.profile:
+
+ [ -f /usr/gnu/bin/bash ] && [ -x /usr/gnu/bin/bash ] && \
+ exec /usr/gnu/bin/bash --login
+
+This will cause login shells to replace themselves with bash running as
+a login shell. Once you have this working, you can copy your initialization
+code from ~/.profile to ~/.bash_profile.
+
+I have received word that the recipe supplied above is insufficient for
+machines running CDE. CDE has a maze of twisty little startup files, all
+slightly different.
+
+If you cannot change your login shell in the password file to bash, you
+will have to (apparently) live with CDE using the shell in the password
+file to run its startup scripts. If you have changed your shell to bash,
+there is code in the CDE startup files (on Solaris, at least) that attempts
+to do the right thing. It is, however, often broken, and may require that
+you use the $BASH_ENV trick described below.
+
+`dtterm' claims to use $SHELL as the default program to start, so if you
+can change $SHELL in the CDE startup files, you should be able to use bash
+in your terminal windows.
+
+Setting DTSOURCEPROFILE in ~/.dtprofile will cause the `Xsession' program
+to read your login shell's startup files. You may be able to use bash for
+the rest of the CDE programs by setting SHELL to bash in ~/.dtprofile as
+well, but I have not tried this.
+
+You can use the above `exec' recipe to start bash when not logging in with
+CDE by testing the value of the DT variable:
+
+ if [ -n "$DT" ]; then
+ [ -f /usr/gnu/bin/bash ] && exec /usr/gnu/bin/bash --login
+ fi
+
+If CDE starts its shells non-interactively during login, the login shell
+startup files (~/.profile, ~/.bash_profile) will not be sourced at login.
+To get around this problem, append a line similar to the following to your
+~/.dtprofile:
+
+ BASH_ENV=${HOME}/.bash_profile ; export BASH_ENV
+
+and add the following line to the beginning of ~/.bash_profile:
+
+ unset BASH_ENV
+
+A8) I just changed my login shell to bash, and now I can't FTP into my
+ machine. Why not?
+
+You must add the full pathname to bash to the file /etc/shells. As
+noted in the answer to the previous question, many systems require
+this before you can make bash your login shell.
+
+Most versions of ftpd use this file to prohibit `special' users
+such as `uucp' and `news' from using FTP.
+
+A9) What's the `POSIX 1003.2 standard'?
+
+POSIX is a name originally coined by Richard Stallman for a
+family of open system standards based on UNIX. There are a
+number of aspects of UNIX under consideration for
+standardization, from the basic system services at the system
+call and C library level to applications and tools to system
+administration and management. Each area of standardization is
+assigned to a working group in the 1003 series.
+
+The POSIX Shell and Utilities standard has been developed by IEEE
+Working Group 1003.2 (POSIX.2). It concentrates on the command
+interpreter interface and utility programs commonly executed from
+the command line or by other programs. An initial version of the
+standard has been approved and published by the IEEE, and work is
+currently underway to update it.
+
+Bash is concerned with the aspects of the shell's behavior
+defined by POSIX.2. The shell command language has of course
+been standardized, including the basic flow control and program
+execution constructs, I/O redirection and pipelining, argument
+handling, variable expansion, and quoting.
+
+The `special' builtins, which must be implemented as part of the
+shell to provide the desired functionality, are specified as
+being part of the shell; examples of these are `eval' and
+`export'. Other utilities appear in the sections of POSIX.2 not
+devoted to the shell which are commonly (and in some cases must
+be) implemented as builtin commands, such as `read' and `test'.
+POSIX.2 also specifies aspects of the shell's interactive
+behavior as part of the UPE, including job control and command
+line editing. Only vi-style line editing commands have been
+standardized; emacs editing commands were left out due to
+objections.
+
+The Open Group has made an older version of its Single Unix
+Specification (version 2), which is very similar to POSIX.2,
+available on the web at
+
+http://www.opengroup.org/onlinepubs/007908799/
+
+The Single Unix Specification, version 3, is available on the web at
+
+http://www.opengroup.org/onlinepubs/007904975/
+
+A10) What is the bash `posix mode'?
+
+Although bash is an implementation of the POSIX.2 shell
+specification, there are areas where the bash default behavior
+differs from that spec. The bash `posix mode' changes the bash
+behavior in these areas so that it obeys the spec more closely.
+
+Posix mode is entered by starting bash with the --posix or
+'-o posix' option or executing `set -o posix' after bash is running.
+
+The specific aspects of bash which change when posix mode is
+active are listed in the file POSIX in the bash distribution.
+They are also listed in a section in the Bash Reference Manual
+(from which that file is generated).
+
+Section B: The latest version
+
+B1) What's new in version 2.05b?
+
+The raison d'etre for bash-2.05b is to make a second intermediate
+release containing the first of the new features to be available
+in bash-3.0 and get feedback on those features before proceeding.
+The major new feature is multibyte character support in both Bash
+and Readline.
+
+Bash-2.05b contains the following new features (see the manual page for
+complete descriptions and the CHANGES and NEWS files in the bash-2.05b
+distribution):
+
+o support for multibyte characters has been added to both bash and readline
+
+o the DEBUG trap is now run *before* simple commands, ((...)) commands,
+ [[...]] conditional commands, and for ((...)) loops
+
+o the shell now performs arithmetic in the largest integer size the machine
+ supports (intmax_t)
+
+o there is a new \D{...} prompt expansion; passes the `...' to strftime(3)
+ and inserts the result into the expanded prompt
+
+o there is a new `here-string' redirection operator: <<< word
+
+o when displaying variables, function attributes and definitions are shown
+ separately, allowing them to be re-used as input (attempting to re-use
+ the old output would result in syntax errors).
+
+o `read' has a new `-u fd' option to read from a specified file descriptor
+
+o the bash debugger in examples/bashdb has been modified to work with the
+ new DEBUG trap semantics, the command set has been made more gdb-like,
+ and the changes to $LINENO make debugging functions work better
+
+o the expansion of $LINENO inside a shell function is only relative to the
+ function start if the shell is interactive -- if the shell is running a
+ script, $LINENO expands to the line number in the script. This is as
+ POSIX-2001 requires
+
+
+A short feature history dating from Bash-2.0:
+
+Bash-2.05a introduced the following new features:
+
+o The `printf' builtin has undergone major work
+
+o There is a new read-only `shopt' option: login_shell, which is set by
+ login shells and unset otherwise
+
+o New `\A' prompt string escape sequence; expanding to time in 24-hour
+ HH:MM format
+
+o New `-A group/-g' option to complete and compgen; goes group name
+ completion
+
+o New [+-]O invocation option to set and unset `shopt' options at startup
+
+o ksh-like `ERR' trap
+
+o `for' loops now allow empty word lists after the `in' reserved word
+
+o new `hard' and `soft' arguments for the `ulimit' builtin
+
+o Readline can be configured to place the user at the same point on the line
+ when retrieving commands from the history list
+
+o Readline can be configured to skip `hidden' files (filenames with a leading
+ `.' on Unix) when performing completion
+
+Bash-2.05 introduced the following new features:
+
+o This version has once again reverted to using locales and strcoll(3) when
+ processing pattern matching bracket expressions, as POSIX requires.
+o Added a new `--init-file' invocation argument as a synonym for `--rcfile',
+ per the new GNU coding standards.
+o The /dev/tcp and /dev/udp redirections now accept service names as well as
+ port numbers.
+o `complete' and `compgen' now take a `-o value' option, which controls some
+ of the aspects of that compspec. Valid values are:
+
+ default - perform bash default completion if programmable
+ completion produces no matches
+ dirnames - perform directory name completion if programmable
+ completion produces no matches
+ filenames - tell readline that the compspec produces filenames,
+ so it can do things like append slashes to
+ directory names and suppress trailing spaces
+o A new loadable builtin, realpath, which canonicalizes and expands symlinks
+ in pathname arguments.
+o When `set' is called without options, it prints function defintions in a
+ way that allows them to be reused as input. This affects `declare' and
+ `declare -p' as well. This only happens when the shell is not in POSIX
+ mode, since POSIX.2 forbids this behavior.
+
+Bash-2.04 introduced the following new features:
+
+o Programmable word completion with the new `complete' and `compgen' builtins;
+ examples are provided in examples/complete/complete-examples
+o `history' has a new `-d' option to delete a history entry
+o `bind' has a new `-x' option to bind key sequences to shell commands
+o The prompt expansion code has new `\j' and `\l' escape sequences
+o The `no_empty_cmd_completion' shell option, if enabled, inhibits
+ command completion when TAB is typed on an empty line
+o `help' has a new `-s' option to print a usage synopsis
+o New arithmetic operators: var++, var--, ++var, --var, expr1,expr2 (comma)
+o New ksh93-style arithmetic for command:
+ for ((expr1 ; expr2; expr3 )); do list; done
+o `read' has new options: `-t', `-n', `-d', `-s'
+o The redirection code handles several filenames specially: /dev/fd/N,
+ /dev/stdin, /dev/stdout, /dev/stderr
+o The redirection code now recognizes /dev/tcp/HOST/PORT and
+ /dev/udp/HOST/PORT and tries to open a TCP or UDP socket, respectively,
+ to the specified port on the specified host
+o The ${!prefix*} expansion has been implemented
+o A new FUNCNAME variable, which expands to the name of a currently-executing
+ function
+o The GROUPS variable is no longer readonly
+o A new shopt `xpg_echo' variable, to control the behavior of echo with
+ respect to backslash-escape sequences at runtime
+o The NON_INTERACTIVE_LOGIN_SHELLS #define has returned
+
+The version of Readline released with Bash-2.04, Readline-4.1, had several
+new features as well:
+
+o Parentheses matching is always compiled into readline, and controllable
+ with the new `blink-matching-paren' variable
+o The history-search-forward and history-search-backward functions now leave
+ point at the end of the line when the search string is empty, like
+ reverse-search-history, and forward-search-history
+o A new function for applications: rl_on_new_line_with_prompt()
+o New variables for applications: rl_already_prompted, and rl_gnu_readline_p
+
+
+Bash-2.03 had very few new features, in keeping with the convention
+that odd-numbered releases provide mainly bug fixes. A number of new
+features were added to Readline, mostly at the request of the Cygnus
+folks.
+
+A new shopt option, `restricted_shell', so that startup files can test
+ whether or not the shell was started in restricted mode
+Filename generation is now performed on the words between ( and ) in
+ compound array assignments (this is really a bug fix)
+OLDPWD is now auto-exported, as POSIX.2 requires
+ENV and BASH_ENV are read-only variables in a restricted shell
+Bash may now be linked against an already-installed Readline library,
+ as long as the Readline library is version 4 or newer
+All shells begun with the `--login' option will source the login shell
+ startup files, even if the shell is not interactive
+
+There were lots of changes to the version of the Readline library released
+along with Bash-2.03. For a complete list of the changes, read the file
+CHANGES in the Bash-2.03 distribution.
+
+Bash-2.02 contained the following new features:
+
+a new version of malloc (based on the old GNU malloc code in previous
+ bash versions) that is more page-oriented, more conservative
+ with memory usage, does not `orphan' large blocks when they
+ are freed, is usable on 64-bit machines, and has allocation
+ checking turned on unconditionally
+POSIX.2-style globbing character classes ([:alpha:], [:alnum:], etc.)
+POSIX.2-style globbing equivalence classes
+POSIX.2-style globbing collating symbols
+the ksh [[...]] extended conditional command
+the ksh egrep-style extended pattern matching operators
+a new `printf' builtin
+the ksh-like $(<filename) command substitution, which is equivalent to
+ $(cat filename)
+new tilde prefixes that expand to directories from the directory stack
+new `**' arithmetic operator to do exponentiation
+case-insensitive globbing (filename expansion)
+menu completion a la tcsh
+`magic-space' history expansion function like tcsh
+the readline inputrc `language' has a new file inclusion directive ($include)
+
+Bash-2.01 contained only a few new features:
+
+new `GROUPS' builtin array variable containing the user's group list
+new bindable readline commands: history-and-alias-expand-line and
+ alias-expand-line
+
+Bash-2.0 contained extensive changes and new features from bash-1.14.7.
+Here's a short list:
+
+new `time' reserved word to time pipelines, shell builtins, and
+ shell functions
+one-dimensional arrays with a new compound assignment statement,
+ appropriate expansion constructs and modifications to some
+ of the builtins (read, declare, etc.) to use them
+new quoting syntaxes for ANSI-C string expansion and locale-specific
+ string translation
+new expansions to do substring extraction, pattern replacement, and
+ indirect variable expansion
+new builtins: `disown' and `shopt'
+new variables: HISTIGNORE, SHELLOPTS, PIPESTATUS, DIRSTACK, GLOBIGNORE,
+ MACHTYPE, BASH_VERSINFO
+special handling of many unused or redundant variables removed
+ (e.g., $notify, $glob_dot_filenames, $no_exit_on_failed_exec)
+dynamic loading of new builtin commands; many loadable examples provided
+new prompt expansions: \a, \e, \n, \H, \T, \@, \v, \V
+history and aliases available in shell scripts
+new readline variables: enable-keypad, mark-directories, input-meta,
+ visible-stats, disable-completion, comment-begin
+new readline commands to manipulate the mark and operate on the region
+new readline emacs mode commands and bindings for ksh-88 compatibility
+updated and extended builtins
+new DEBUG trap
+expanded (and now documented) restricted shell mode
+
+implementation stuff:
+autoconf-based configuration
+nearly all of the bugs reported since version 1.14 have been fixed
+most builtins converted to use builtin `getopt' for consistency
+most builtins use -p option to display output in a reusable form
+ (for consistency)
+grammar tighter and smaller (66 reduce-reduce conflicts gone)
+lots of code now smaller and faster
+test suite greatly expanded
+
+B2) Are there any user-visible incompatibilities between bash-2.05b and
+ bash-1.14.7?
+
+There are a few incompatibilities between version 1.14.7 and version 2.05b.
+They are detailed in the file COMPAT in the bash distribution. That file
+is not meant to be all-encompassing; send mail to bash-maintainers@gnu.org
+if if you find something that's not mentioned there.
+
+Section C: Differences from other Unix shells
+
+C1) How does bash differ from sh, the Bourne shell?
+
+This is a non-comprehensive list of features that differentiate bash
+from the SVR4.2 shell. The bash manual page explains these more
+completely.
+
+Things bash has that sh does not:
+ long invocation options
+ [+-]O invocation option
+ -l invocation option
+ `!' reserved word to invert pipeline return value
+ `time' reserved word to time pipelines and shell builtins
+ the `function' reserved word
+ the `select' compound command and reserved word
+ arithmetic for command: for ((expr1 ; expr2; expr3 )); do list; done
+ new $'...' and $"..." quoting
+ the $(...) form of command substitution
+ the $(<filename) form of command substitution, equivalent to
+ $(cat filename)
+ the ${#param} parameter value length operator
+ the ${!param} indirect parameter expansion operator
+ the ${!param*} prefix expansion operator
+ the ${param:offset[:length]} parameter substring operator
+ the ${param/pat[/string]} parameter pattern substitution operator
+ expansions to perform substring removal (${p%[%]w}, ${p#[#]w})
+ expansion of positional parameters beyond $9 with ${num}
+ variables: BASH, BASH_VERSION, BASH_VERSINFO, UID, EUID, REPLY,
+ TIMEFORMAT, PPID, PWD, OLDPWD, SHLVL, RANDOM, SECONDS,
+ LINENO, HISTCMD, HOSTTYPE, OSTYPE, MACHTYPE, HOSTNAME,
+ ENV, PS3, PS4, DIRSTACK, PIPESTATUS, HISTSIZE, HISTFILE,
+ HISTFILESIZE, HISTCONTROL, HISTIGNORE, GLOBIGNORE, GROUPS,
+ PROMPT_COMMAND, FCEDIT, FIGNORE, IGNOREEOF, INPUTRC,
+ SHELLOPTS, OPTERR, HOSTFILE, TMOUT, FUNCNAME, histchars,
+ auto_resume
+ DEBUG trap
+ ERR trap
+ variable arrays with new compound assignment syntax
+ redirections: <>, &>, >|, <<<, [n]<&word-, [n]>&word-
+ prompt string special char translation and variable expansion
+ auto-export of variables in initial environment
+ command search finds functions before builtins
+ bash return builtin will exit a file sourced with `.'
+ builtins: cd -/-L/-P, exec -l/-c/-a, echo -e/-E, hash -d/-l/-p/-t.
+ export -n/-f/-p/name=value, pwd -L/-P,
+ read -e/-p/-a/-t/-n/-d/-s/-u,
+ readonly -a/-f/name=value, trap -l, set +o,
+ set -b/-m/-o option/-h/-p/-B/-C/-H/-P,
+ unset -f/-v, ulimit -m/-p/-u,
+ type -a/-p/-t/-f/-P, suspend -f, kill -n,
+ test -o optname/s1 == s2/s1 < s2/s1 > s2/-nt/-ot/-ef/-O/-G/-S
+ bash reads ~/.bashrc for interactive shells, $ENV for non-interactive
+ bash restricted shell mode is more extensive
+ bash allows functions and variables with the same name
+ brace expansion
+ tilde expansion
+ arithmetic expansion with $((...)) and `let' builtin
+ the `[[...]]' extended conditional command
+ process substitution
+ aliases and alias/unalias builtins
+ local variables in functions and `local' builtin
+ readline and command-line editing with programmable completion
+ command history and history/fc builtins
+ csh-like history expansion
+ other new bash builtins: bind, command, compgen, complete, builtin,
+ declare/typeset, dirs, enable, fc, help,
+ history, logout, popd, pushd, disown, shopt,
+ printf
+ exported functions
+ filename generation when using output redirection (command >a*)
+ POSIX.2-style globbing character classes
+ POSIX.2-style globbing equivalence classes
+ POSIX.2-style globbing collating symbols
+ egrep-like extended pattern matching operators
+ case-insensitive pattern matching and globbing
+ variable assignments preceding commands affect only that command,
+ even for builtins and functions
+ posix mode
+ redirection to /dev/fd/N, /dev/stdin, /dev/stdout, /dev/stderr,
+ /dev/tcp/host/port, /dev/udp/host/port
+
+Things sh has that bash does not:
+ uses variable SHACCT to do shell accounting
+ includes `stop' builtin (bash can use alias stop='kill -s STOP')
+ `newgrp' builtin
+ turns on job control if called as `jsh'
+ $TIMEOUT (like bash $TMOUT)
+ `^' is a synonym for `|'
+ new SVR4.2 sh builtins: mldmode, priv
+
+Implementation differences:
+ redirection to/from compound commands causes sh to create a subshell
+ bash does not allow unbalanced quotes; sh silently inserts them at EOF
+ bash does not mess with signal 11
+ sh sets (euid, egid) to (uid, gid) if -p not supplied and uid < 100
+ bash splits only the results of expansions on IFS, using POSIX.2
+ field splitting rules; sh splits all words on IFS
+ sh does not allow MAILCHECK to be unset (?)
+ sh does not allow traps on SIGALRM or SIGCHLD
+ bash allows multiple option arguments when invoked (e.g. -x -v);
+ sh allows only a single option argument (`sh -x -v' attempts
+ to open a file named `-v', and, on SunOS 4.1.4, dumps core.
+ On Solaris 2.4 and earlier versions, sh goes into an infinite
+ loop.)
+ sh exits a script if any builtin fails; bash exits only if one of
+ the POSIX.2 `special' builtins fails
+
+C2) How does bash differ from the Korn shell, version ksh88?
+
+Things bash has or uses that ksh88 does not:
+ long invocation options
+ [-+]O invocation option
+ -l invocation option
+ `!' reserved word
+ arithmetic for command: for ((expr1 ; expr2; expr3 )); do list; done
+ arithmetic in largest machine-supported size (intmax_t)
+ posix mode and posix conformance
+ command hashing
+ tilde expansion for assignment statements that look like $PATH
+ process substitution with named pipes if /dev/fd is not available
+ the ${!param} indirect parameter expansion operator
+ the ${!param*} prefix expansion operator
+ the ${param:offset[:length]} parameter substring operator
+ the ${param/pat[/string]} parameter pattern substitution operator
+ variables: BASH, BASH_VERSION, BASH_VERSINFO, UID, EUID, SHLVL,
+ TIMEFORMAT, HISTCMD, HOSTTYPE, OSTYPE, MACHTYPE,
+ HISTFILESIZE, HISTIGNORE, HISTCONTROL, PROMPT_COMMAND,
+ IGNOREEOF, FIGNORE, INPUTRC, HOSTFILE, DIRSTACK,
+ PIPESTATUS, HOSTNAME, OPTERR, SHELLOPTS, GLOBIGNORE,
+ GROUPS, FUNCNAME, histchars, auto_resume
+ prompt expansion with backslash escapes and command substitution
+ redirection: &> (stdout and stderr), <<<, [n]<&word-, [n]>&word-
+ more extensive and extensible editing and programmable completion
+ builtins: bind, builtin, command, declare, dirs, echo -e/-E, enable,
+ exec -l/-c/-a, fc -s, export -n/-f/-p, hash, help, history,
+ jobs -x/-r/-s, kill -s/-n/-l, local, logout, popd, pushd,
+ read -e/-p/-a/-t/-n/-d/-s, readonly -a/-n/-f/-p,
+ set -o braceexpand/-o histexpand/-o interactive-comments/
+ -o notify/-o physical/-o posix/-o hashall/-o onecmd/
+ -h/-B/-C/-b/-H/-P, set +o, suspend, trap -l, type,
+ typeset -a/-F/-p, ulimit -u, umask -S, alias -p, shopt,
+ disown, printf, complete, compgen
+ `!' csh-style history expansion
+ POSIX.2-style globbing character classes
+ POSIX.2-style globbing equivalence classes
+ POSIX.2-style globbing collating symbols
+ egrep-like extended pattern matching operators
+ case-insensitive pattern matching and globbing
+ `**' arithmetic operator to do exponentiation
+ redirection to /dev/fd/N, /dev/stdin, /dev/stdout, /dev/stderr
+ arrays of unlimited size
+ TMOUT is default timeout for `read' and `select'
+
+Things ksh88 has or uses that bash does not:
+ tracked aliases (alias -t)
+ variables: ERRNO, FPATH, EDITOR, VISUAL
+ co-processes (|&, >&p, <&p)
+ weirdly-scoped functions
+ typeset +f to list all function names without definitions
+ text of command history kept in a file, not memory
+ builtins: alias -x, cd old new, fc -e -, newgrp, print,
+ read -p/-s/var?prompt, set -A/-o gmacs/
+ -o bgnice/-o markdirs/-o nolog/-o trackall/-o viraw/-s,
+ typeset -H/-L/-R/-Z/-A/-ft/-fu/-fx/-l/-u/-t, whence
+ using environment to pass attributes of exported variables
+ arithmetic evaluation done on arguments to some builtins
+ reads .profile from $PWD when invoked as login shell
+
+Implementation differences:
+ ksh runs last command of a pipeline in parent shell context
+ bash has brace expansion by default (ksh88 compile-time option)
+ bash has fixed startup file for all interactive shells; ksh reads $ENV
+ bash has exported functions
+ bash command search finds functions before builtins
+ bash waits for all commands in pipeline to exit before returning status
+ emacs-mode editing has some slightly different key bindings
+
+C3) Which new features in ksh-93 are not in bash, and which are?
+
+New things in ksh-93 not in bash-2.05b:
+ associative arrays
+ floating point arithmetic and variables
+ math library functions
+ ${!name[sub]} name of subscript for associative array
+ `.' is allowed in variable names to create a hierarchical namespace
+ more extensive compound assignment syntax
+ discipline functions
+ `sleep' and `getconf' builtins (bash has loadable versions)
+ typeset -n and `nameref' variables
+ KEYBD trap
+ variables: .sh.edchar, .sh.edmode, .sh.edcol, .sh.edtext, .sh.version,
+ .sh.name, .sh.subscript, .sh.value, .sh.match, HISTEDIT
+ backreferences in pattern matching (\N)
+ `&' operator in pattern lists for matching
+ print -f (bash uses printf)
+ `fc' has been renamed to `hist'
+ `.' can execute shell functions
+ exit statuses between 0 and 255
+ set -o pipefail
+ `+=' variable assignment operator
+ FPATH and PATH mixing
+ getopts -a
+ -I invocation option
+ DEBUG trap now executed before each simple command, instead of after
+ printf %H, %P, %T, %Z modifiers, output base for %d
+ lexical scoping for local variables in `ksh' functions
+ no scoping for local variables in `POSIX' functions
+
+New things in ksh-93 present in bash-2.05b:
+ [n]<&word- and [n]>&word- redirections (combination dup and close)
+ for (( expr1; expr2; expr3 )) ; do list; done - arithmetic for command
+ ?:, ++, --, `expr1 , expr2' arithmetic operators
+ expansions: ${!param}, ${param:offset[:len]}, ${param/pat[/str]},
+ ${!param*}
+ compound array assignment
+ the `!' reserved word
+ loadable builtins -- but ksh uses `builtin' while bash uses `enable'
+ `command', `builtin', `disown' builtins
+ new $'...' and $"..." quoting
+ FIGNORE (but bash uses GLOBIGNORE), HISTCMD
+ set -o notify/-C
+ changes to kill builtin
+ read -A (bash uses read -a)
+ read -t/-d
+ trap -p
+ exec -c/-a
+ `.' restores the positional parameters when it completes
+ POSIX.2 `test'
+ umask -S
+ unalias -a
+ command and arithmetic substitution performed on PS1, PS4, and ENV
+ command name completion
+ ENV processed only for interactive shells
+
+Section D: Why does bash do some things differently than other Unix shells?
+
+D1) Why does bash run a different version of `command' than
+ `which command' says it will?
+
+On many systems, `which' is actually a csh script that assumes
+you're running csh. In tcsh, `which' and its cousin `where'
+are builtins. On other Unix systems, `which' is a perl script
+that uses the PATH environment variable.
+
+The csh script version reads the csh startup files from your
+home directory and uses those to determine which `command' will
+be invoked. Since bash doesn't use any of those startup files,
+there's a good chance that your bash environment differs from
+your csh environment. The bash `type' builtin does everything
+`which' does, and will report correct results for the running
+shell. If you're really wedded to the name `which', try adding
+the following function definition to your .bashrc:
+
+ which()
+ {
+ builtin type "$@"
+ }
+
+If you're moving from tcsh and would like to bring `where' along
+as well, use this function:
+
+ where()
+ {
+ builtin type -a "$@"
+ }
+
+D2) Why doesn't bash treat brace expansions exactly like csh?
+
+The only difference between bash and csh brace expansion is that
+bash requires a brace expression to contain at least one unquoted
+comma if it is to be expanded. Any brace-surrounded word not
+containing an unquoted comma is left unchanged by the brace
+expansion code. This affords the greatest degree of sh
+compatibility.
+
+Bash, ksh, zsh, and pd-ksh all implement brace expansion this way.
+
+D3) Why doesn't bash have csh variable modifiers?
+
+Posix has specified a more powerful, albeit somewhat more cryptic,
+mechanism cribbed from ksh, and bash implements it.
+
+${parameter%word}
+ Remove smallest suffix pattern. The WORD is expanded to produce
+ a pattern. It then expands to the value of PARAMETER, with the
+ smallest portion of the suffix matched by the pattern deleted.
+
+ x=file.c
+ echo ${x%.c}.o
+ -->file.o
+
+${parameter%%word}
+
+ Remove largest suffix pattern. The WORD is expanded to produce
+ a pattern. It then expands to the value of PARAMETER, with the
+ largest portion of the suffix matched by the pattern deleted.
+
+ x=posix/src/std
+ echo ${x%%/*}
+ -->posix
+
+${parameter#word}
+ Remove smallest prefix pattern. The WORD is expanded to produce
+ a pattern. It then expands to the value of PARAMETER, with the
+ smallest portion of the prefix matched by the pattern deleted.
+
+ x=$HOME/src/cmd
+ echo ${x#$HOME}
+ -->/src/cmd
+
+${parameter##word}
+ Remove largest prefix pattern. The WORD is expanded to produce
+ a pattern. It then expands to the value of PARAMETER, with the
+ largest portion of the prefix matched by the pattern deleted.
+
+ x=/one/two/three
+ echo ${x##*/}
+ -->three
+
+
+Given
+ a=/a/b/c/d
+ b=b.xxx
+
+ csh bash result
+ --- ---- ------
+ $a:h ${a%/*} /a/b/c
+ $a:t ${a##*/} d
+ $b:r ${b%.*} b
+ $b:e ${b##*.} xxx
+
+
+D4) How can I make my csh aliases work when I convert to bash?
+
+Bash uses a different syntax to support aliases than csh does.
+The details can be found in the documentation. We have provided
+a shell script which does most of the work of conversion for you;
+this script can be found in ./examples/misc/aliasconv.sh. Here is
+how you use it:
+
+Start csh in the normal way for you. (e.g., `csh')
+
+Pipe the output of `alias' through `aliasconv.sh', saving the
+results into `bash_aliases':
+
+ alias | bash aliasconv.sh >bash_aliases
+
+Edit `bash_aliases', carefully reading through any created
+functions. You will need to change the names of some csh specific
+variables to the bash equivalents. The script converts $cwd to
+$PWD, $term to $TERM, $home to $HOME, $user to $USER, and $prompt
+to $PS1. You may also have to add quotes to avoid unwanted
+expansion.
+
+For example, the csh alias:
+
+ alias cd 'cd \!*; echo $cwd'
+
+is converted to the bash function:
+
+ cd () { command cd "$@"; echo $PWD ; }
+
+The only thing that needs to be done is to quote $PWD:
+
+ cd () { command cd "$@"; echo "$PWD" ; }
+
+Merge the edited file into your ~/.bashrc.
+
+There is an additional, more ambitious, script in
+examples/misc/cshtobash that attempts to convert your entire csh
+environment to its bash equivalent. This script can be run as
+simply `cshtobash' to convert your normal interactive
+environment, or as `cshtobash ~/.login' to convert your login
+environment.
+
+D5) How can I pipe standard output and standard error from one command to
+ another, like csh does with `|&'?
+
+Use
+ command 2>&1 | command2
+
+The key is to remember that piping is performed before redirection, so
+file descriptor 1 points to the pipe when it is duplicated onto file
+descriptor 2.
+
+D6) Now that I've converted from ksh to bash, are there equivalents to
+ ksh features like autoloaded functions and the `whence' command?
+
+There are features in ksh-88 and ksh-93 that do not have direct bash
+equivalents. Most, however, can be emulated with very little trouble.
+
+ksh-88 feature Bash equivalent
+-------------- ---------------
+compiled-in aliases set up aliases in .bashrc; some ksh aliases are
+ bash builtins (hash, history, type)
+coprocesses named pipe pairs (one for read, one for write)
+typeset +f declare -F
+cd, print, whence function substitutes in examples/functions/kshenv
+autoloaded functions examples/functions/autoload is the same as typeset -fu
+read var?prompt read -p prompt var
+
+ksh-93 feature Bash equivalent
+-------------- ---------------
+sleep, getconf Bash has loadable versions in examples/loadables
+${.sh.version} $BASH_VERSION
+print -f printf
+hist alias hist=fc
+$HISTEDIT $FCEDIT
+
+Section E: How can I get bash to do certain things, and why does bash do
+ things the way it does?
+
+E1) Why is the bash builtin `test' slightly different from /bin/test?
+
+The specific example used here is [ ! x -o x ], which is false.
+
+Bash's builtin `test' implements the Posix.2 spec, which can be
+summarized as follows (the wording is due to David Korn):
+
+Here is the set of rules for processing test arguments.
+
+ 0 Args: False
+ 1 Arg: True iff argument is not null.
+ 2 Args: If first arg is !, True iff second argument is null.
+ If first argument is unary, then true if unary test is true
+ Otherwise error.
+ 3 Args: If second argument is a binary operator, do binary test of $1 $3
+ If first argument is !, negate two argument test of $2 $3
+ If first argument is `(' and third argument is `)', do the
+ one-argument test of the second argument.
+ Otherwise error.
+ 4 Args: If first argument is !, negate three argument test of $2 $3 $4.
+ Otherwise unspecified
+ 5 or more Args: unspecified. (Historical shells would use their
+ current algorithm).
+
+The operators -a and -o are considered binary operators for the purpose
+of the 3 Arg case.
+
+As you can see, the test becomes (not (x or x)), which is false.
+
+E2) Why does bash sometimes say `Broken pipe'?
+
+If a sequence of commands appears in a pipeline, and one of the
+reading commands finishes before the writer has finished, the
+writer receives a SIGPIPE signal. Many other shells special-case
+SIGPIPE as an exit status in the pipeline and do not report it.
+For example, in:
+
+ ps -aux | head
+
+`head' can finish before `ps' writes all of its output, and ps
+will try to write on a pipe without a reader. In that case, bash
+will print `Broken pipe' to stderr when ps is killed by a
+SIGPIPE.
+
+You can build a version of bash that will not report SIGPIPE errors
+by uncommenting the definition of DONT_REPORT_SIGPIPE in the file
+config-top.h.
+
+E3) When I have terminal escape sequences in my prompt, why does bash
+ wrap lines at the wrong column?
+
+Readline, the line editing library that bash uses, does not know
+that the terminal escape sequences do not take up space on the
+screen. The redisplay code assumes, unless told otherwise, that
+each character in the prompt is a `printable' character that
+takes up one character position on the screen.
+
+You can use the bash prompt expansion facility (see the PROMPTING
+section in the manual page) to tell readline that sequences of
+characters in the prompt strings take up no screen space.
+
+Use the \[ escape to begin a sequence of non-printing characters,
+and the \] escape to signal the end of such a sequence.
+
+E4) If I pipe the output of a command into `read variable', why doesn't
+ the output show up in $variable when the read command finishes?
+
+This has to do with the parent-child relationship between Unix
+processes. It affects all commands run in pipelines, not just
+simple calls to `read'. For example, piping a command's output
+into a `while' loop that repeatedly calls `read' will result in
+the same behavior.
+
+Each element of a pipeline runs in a separate process, a child of
+the shell running the pipeline. A subprocess cannot affect its
+parent's environment. When the `read' command sets the variable
+to the input, that variable is set only in the subshell, not the
+parent shell. When the subshell exits, the value of the variable
+is lost.
+
+Many pipelines that end with `read variable' can be converted
+into command substitutions, which will capture the output of
+a specified command. The output can then be assigned to a
+variable:
+
+ grep ^gnu /usr/lib/news/active | wc -l | read ngroup
+
+can be converted into
+
+ ngroup=$(grep ^gnu /usr/lib/news/active | wc -l)
+
+This does not, unfortunately, work to split the text among
+multiple variables, as read does when given multiple variable
+arguments. If you need to do this, you can either use the
+command substitution above to read the output into a variable
+and chop up the variable using the bash pattern removal
+expansion operators or use some variant of the following
+approach.
+
+Say /usr/local/bin/ipaddr is the following shell script:
+
+#! /bin/sh
+host `hostname` | awk '/address/ {print $NF}'
+
+Instead of using
+
+ /usr/local/bin/ipaddr | read A B C D
+
+to break the local machine's IP address into separate octets, use
+
+ OIFS="$IFS"
+ IFS=.
+ set -- $(/usr/local/bin/ipaddr)
+ IFS="$OIFS"
+ A="$1" B="$2" C="$3" D="$4"
+
+Beware, however, that this will change the shell's positional
+parameters. If you need them, you should save them before doing
+this.
+
+This is the general approach -- in most cases you will not need to
+set $IFS to a different value.
+
+Some other user-supplied alternatives include:
+
+read A B C D << HERE
+ $(IFS=.; echo $(/usr/local/bin/ipaddr))
+HERE
+
+and, where process substitution is available,
+
+read A B C D < <(IFS=.; echo $(/usr/local/bin/ipaddr))
+
+E5) I have a bunch of shell scripts that use backslash-escaped characters
+ in arguments to `echo'. Bash doesn't interpret these characters. Why
+ not, and how can I make it understand them?
+
+This is the behavior of echo on most Unix System V machines.
+
+The bash builtin `echo' is modeled after the 9th Edition
+Research Unix version of `echo'. It does not interpret
+backslash-escaped characters in its argument strings by default;
+it requires the use of the -e option to enable the
+interpretation. The System V echo provides no way to disable the
+special characters; the bash echo has a -E option to disable
+them.
+
+There is a configuration option that will make bash behave like
+the System V echo and interpret things like `\t' by default. Run
+configure with the --enable-xpg-echo-default option to turn this
+on. Be aware that this will cause some of the tests run when you
+type `make tests' to fail.
+
+There is a shell option, `xpg_echo', settable with `shopt', that will
+change the behavior of echo at runtime. Enabling this option turns
+on expansion of backslash-escape sequences.
+
+E6) Why doesn't a while or for loop get suspended when I type ^Z?
+
+This is a consequence of how job control works on Unix. The only
+thing that can be suspended is the process group. This is a single
+command or pipeline of commands that the shell forks and executes.
+
+When you run a while or for loop, the only thing that the shell forks
+and executes are any commands in the while loop test and commands in
+the loop bodies. These, therefore, are the only things that can be
+suspended when you type ^Z.
+
+If you want to be able to stop the entire loop, you need to put it
+within parentheses, which will force the loop into a subshell that
+may be stopped (and subsequently restarted) as a single unit.
+
+E7) What about empty for loops in Makefiles?
+
+It's fairly common to see constructs like this in automatically-generated
+Makefiles:
+
+SUBDIRS = @SUBDIRS@
+
+ ...
+
+subdirs-clean:
+ for d in ${SUBDIRS}; do \
+ ( cd $$d && ${MAKE} ${MFLAGS} clean ) \
+ done
+
+When SUBDIRS is empty, this results in a command like this being passed to
+bash:
+
+ for d in ; do
+ ( cd $d && ${MAKE} ${MFLAGS} clean )
+ done
+
+In versions of bash before bash-2.05a, this was a syntax error. If the
+reserved word `in' was present, a word must follow it before the semicolon
+or newline. The language in the manual page referring to the list of words
+being empty referred to the list after it is expanded. These versions of
+bash required that there be at least one word following the `in' when the
+construct was parsed.
+
+The idiomatic Makefile solution is something like:
+
+SUBDIRS = @SUBDIRS@
+
+subdirs-clean:
+ subdirs=$SUBDIRS ; for d in $$subdirs; do \
+ ( cd $$d && ${MAKE} ${MFLAGS} clean ) \
+ done
+
+The latest drafts of the updated POSIX standard have changed this: the
+word list is no longer required. Bash versions 2.05a and later accept
+the new syntax.
+
+E8) Why does the arithmetic evaluation code complain about `08'?
+
+The bash arithmetic evaluation code (used for `let', $(()), (()), and in
+other places), interprets a leading `0' in numeric constants as denoting
+an octal number, and a leading `0x' as denoting hexadecimal. This is
+in accordance with the POSIX.2 spec, section 2.9.2.1, which states that
+arithmetic constants should be handled as signed long integers as defined
+by the ANSI/ISO C standard.
+
+The POSIX.2 interpretation committee has confirmed this:
+
+http://www.pasc.org/interps/unofficial/db/p1003.2/pasc-1003.2-173.html
+
+E9) Why does the pattern matching expression [A-Z]* match files beginning
+ with every letter except `z'?
+
+Bash-2.03, Bash-2.05 and later versions honor the current locale setting
+when processing ranges within pattern matching bracket expressions ([A-Z]).
+This is what POSIX.2 and SUSv3/XPG6 specify.
+
+The behavior of the matcher in bash-2.05 and later versions depends on the
+current LC_COLLATE setting. Setting this variable to `C' or `POSIX' will
+result in the traditional behavior ([A-Z] matches all uppercase ASCII
+characters). Many other locales, including the en_US locale (the default
+on many US versions of Linux) collate the upper and lower case letters like
+this:
+
+ AaBb...Zz
+
+which means that [A-Z] matches every letter except `z'. Others collate like
+
+ aAbBcC...zZ
+
+which means that [A-Z] matches every letter except `a'.
+
+The portable way to specify upper case letters is [:upper:] instead of
+A-Z; lower case may be specified as [:lower:] instead of a-z.
+
+Look at the manual pages for setlocale(3), strcoll(3), and, if it is
+present, locale(1). If you have locale(1), you can use it to find
+your current locale information even if you do not have any of the
+LC_ variables set.
+
+My advice is to put
+
+ export LC_COLLATE=C
+
+into /etc/profile and inspect any shell scripts run from cron for
+constructs like [A-Z]. This will prevent things like
+
+ rm [A-Z]*
+
+from removing every file in the current directory except those beginning
+with `z' and still allow individual users to change the collation order.
+Users may put the above command into their own profiles as well, of course.
+
+E10) Why does `cd //' leave $PWD as `//'?
+
+POSIX.2, in its description of `cd', says that *three* or more leading
+slashes may be replaced with a single slash when canonicalizing the
+current working directory.
+
+This is, I presume, for historical compatibility. Certain versions of
+Unix, and early network file systems, used paths of the form
+//hostname/path to access `path' on server `hostname'.
+
+E11) If I resize my xterm while another program is running, why doesn't bash
+ notice the change?
+
+This is another issue that deals with job control.
+
+The kernel maintains a notion of a current terminal process group. Members
+of this process group (processes whose process group ID is equal to the
+current terminal process group ID) receive terminal-generated signals like
+SIGWINCH. (For more details, see the JOB CONTROL section of the bash
+man page.)
+
+If a terminal is resized, the kernel sends SIGWINCH to each member of
+the terminal's current process group (the `foreground' process group).
+
+When bash is running with job control enabled, each pipeline (which may be
+a single command) is run in its own process group, different from bash's
+process group. This foreground process group receives the SIGWINCH; bash
+does not. Bash has no way of knowing that the terminal has been resized.
+
+There is a `checkwinsize' option, settable with the `shopt' builtin, that
+will cause bash to check the window size and adjust its idea of the
+terminal's dimensions each time a process stops or exits and returns control
+of the terminal to bash. Enable it with `shopt -s checkwinsize'.
+
+Section F: Things to watch out for on certain Unix versions
+
+F1) Why can't I use command line editing in my `cmdtool'?
+
+The problem is `cmdtool' and bash fighting over the input. When
+scrolling is enabled in a cmdtool window, cmdtool puts the tty in
+`raw mode' to permit command-line editing using the mouse for
+applications that cannot do it themselves. As a result, bash and
+cmdtool each try to read keyboard input immediately, with neither
+getting enough of it to be useful.
+
+This mode also causes cmdtool to not implement many of the
+terminal functions and control sequences appearing in the
+`sun-cmd' termcap entry. For a more complete explanation, see
+that file examples/suncmd.termcap in the bash distribution.
+
+`xterm' is a better choice, and gets along with bash much more
+smoothly.
+
+If you must use cmdtool, you can use the termcap description in
+examples/suncmd.termcap. Set the TERMCAP variable to the terminal
+description contained in that file, i.e.
+
+TERMCAP='Mu|sun-cmd:am:bs:km:pt:li#34:co#80:cl=^L:ce=\E[K:cd=\E[J:rs=\E[s:'
+
+Then export TERMCAP and start a new cmdtool window from that shell.
+The bash command-line editing should behave better in the new
+cmdtool. If this works, you can put the assignment to TERMCAP
+in your bashrc file.
+
+F2) I built bash on Solaris 2. Why do globbing expansions and filename
+ completion chop off the first few characters of each filename?
+
+This is the consequence of building bash on SunOS 5 and linking
+with the libraries in /usr/ucblib, but using the definitions
+and structures from files in /usr/include.
+
+The actual conflict is between the dirent structure in
+/usr/include/dirent.h and the struct returned by the version of
+`readdir' in libucb.a (a 4.3-BSD style `struct direct').
+
+Make sure you've got /usr/ccs/bin ahead of /usr/ucb in your $PATH
+when configuring and building bash. This will ensure that you
+use /usr/ccs/bin/cc or acc instead of /usr/ucb/cc and that you
+link with libc before libucb.
+
+If you have installed the Sun C compiler, you may also need to
+put /usr/ccs/bin and /opt/SUNWspro/bin into your $PATH before
+/usr/ucb.
+
+F3) Why does bash dump core after I interrupt username completion or
+ `~user' tilde expansion on a machine running NIS?
+
+This is a famous and long-standing bug in the SunOS YP (sorry, NIS)
+client library, which is part of libc.
+
+The YP library code keeps static state -- a pointer into the data
+returned from the server. When YP initializes itself (setpwent),
+it looks at this pointer and calls free on it if it's non-null.
+So far, so good.
+
+If one of the YP functions is interrupted during getpwent (the
+exact function is interpretwithsave()), and returns NULL, the
+pointer is freed without being reset to NULL, and the function
+returns. The next time getpwent is called, it sees that this
+pointer is non-null, calls free, and the bash free() blows up
+because it's being asked to free freed memory.
+
+The traditional Unix mallocs allow memory to be freed multiple
+times; that's probably why this has never been fixed. You can
+run configure with the `--without-gnu-malloc' option to use
+the C library malloc and avoid the problem.
+
+F4) I'm running SVR4.2. Why is the line erased every time I type `@'?
+
+The `@' character is the default `line kill' character in most
+versions of System V, including SVR4.2. You can change this
+character to whatever you want using `stty'. For example, to
+change the line kill character to control-u, type
+
+ stty kill ^U
+
+where the `^' and `U' can be two separate characters.
+
+F5) Why does bash report syntax errors when my C News scripts use a
+ redirection before a subshell command?
+
+The actual command in question is something like
+
+ < file ( command )
+
+According to the grammar given in the POSIX.2 standard, this construct
+is, in fact, a syntax error. Redirections may only precede `simple
+commands'. A subshell construct such as the above is one of the shell's
+`compound commands'. A redirection may only follow a compound command.
+
+This affects the mechanical transformation of commands that use `cat'
+to pipe a file into a command (a favorite Useless-Use-Of-Cat topic on
+comp.unix.shell). While most commands of the form
+
+ cat file | command
+
+can be converted to `< file command', shell control structures such as
+loops and subshells require `command < file'.
+
+The file CWRU/sh-redir-hack in the bash-2.05a distribution is an
+(unofficial) patch to parse.y that will modify the grammar to
+support this construct. It will not apply with `patch'; you must
+modify parse.y by hand. Note that if you apply this, you must
+recompile with -DREDIRECTION_HACK. This introduces a large
+number of reduce/reduce conflicts into the shell grammar.
+
+F6) Why can't I use vi-mode editing on Red Hat Linux 6.1?
+
+The short answer is that Red Hat screwed up.
+
+The long answer is that they shipped an /etc/inputrc that only works
+for emacs mode editing, and then screwed all the vi users by setting
+INPUTRC to /etc/inputrc in /etc/profile.
+
+The short fix is to do one of the following: remove or rename
+/etc/inputrc, set INPUTRC=~/.inputrc in ~/.bashrc (or .bash_profile,
+but make sure you export it if you do), remove the assignment to
+INPUTRC from /etc/profile, add
+
+ set keymap emacs
+
+to the beginning of /etc/inputrc, or bracket the key bindings in
+/etc/inputrc with these lines
+
+ $if mode=emacs
+ [...]
+ $endif
+
+F7) Why do bash-2.05a and bash-2.05b fail to compile `printf.def' on
+ HP/UX 11.x?
+
+HP/UX's support for long double is imperfect at best.
+
+GCC will support it without problems, but the HP C library functions
+like strtold(3) and printf(3) don't actually work with long doubles.
+HP implemented a `long_double' type as a 4-element array of 32-bit
+ints, and that is what the library functions use. The ANSI C
+`long double' type is a 128-bit floating point scalar.
+
+The easiest fix, until HP fixes things up, is to edit the generated
+config.h and #undef the HAVE_LONG_DOUBLE line. After doing that,
+the compilation should complete successfully.
+
+Section G: How can I get bash to do certain common things?
+
+G1) How can I get bash to read and display eight-bit characters?
+
+This is a process requiring several steps.
+
+First, you must ensure that the `physical' data path is a full eight
+bits. For xterms, for example, the `vt100' resources `eightBitInput'
+and `eightBitOutput' should be set to `true'.
+
+Once you have set up an eight-bit path, you must tell the kernel and
+tty driver to leave the eighth bit of characters alone when processing
+keyboard input. Use `stty' to do this:
+
+ stty cs8 -istrip -parenb
+
+For old BSD-style systems, you can use
+
+ stty pass8
+
+You may also need
+
+ stty even odd
+
+Finally, you need to tell readline that you will be inputting and
+displaying eight-bit characters. You use readline variables to do
+this. These variables can be set in your .inputrc or using the bash
+`bind' builtin. Here's an example using `bind':
+
+ bash$ bind 'set convert-meta off'
+ bash$ bind 'set meta-flag on'
+ bash$ bind 'set output-meta on'
+
+The `set' commands between the single quotes may also be placed
+in ~/.inputrc.
+
+G2) How do I write a function `x' to replace builtin command `x', but
+ still invoke the command from within the function?
+
+This is why the `command' and `builtin' builtins exist. The
+`command' builtin executes the command supplied as its first
+argument, skipping over any function defined with that name. The
+`builtin' builtin executes the builtin command given as its first
+argument directly.
+
+For example, to write a function to replace `cd' that writes the
+hostname and current directory to an xterm title bar, use
+something like the following:
+
+ cd()
+ {
+ builtin cd "$@" && xtitle "$HOST: $PWD"
+ }
+
+This could also be written using `command' instead of `builtin';
+the version above is marginally more efficient.
+
+G3) How can I find the value of a shell variable whose name is the value
+ of another shell variable?
+
+Versions of Bash newer than Bash-2.0 support this directly. You can use
+
+ ${!var}
+
+For example, the following sequence of commands will echo `z':
+
+ var1=var2
+ var2=z
+ echo ${!var1}
+
+For sh compatibility, use the `eval' builtin. The important
+thing to remember is that `eval' expands the arguments you give
+it again, so you need to quote the parts of the arguments that
+you want `eval' to act on.
+
+For example, this expression prints the value of the last positional
+parameter:
+
+ eval echo \"\$\{$#\}\"
+
+The expansion of the quoted portions of this expression will be
+deferred until `eval' runs, while the `$#' will be expanded
+before `eval' is executed. In versions of bash later than bash-2.0,
+
+ echo ${!#}
+
+does the same thing.
+
+This is not the same thing as ksh93 `nameref' variables, though the syntax
+is similar. I may add namerefs in a future bash version.
+
+G4) How can I make the bash `time' reserved word print timing output that
+ looks like the output from my system's /usr/bin/time?
+
+The bash command timing code looks for a variable `TIMEFORMAT' and
+uses its value as a format string to decide how to display the
+timing statistics.
+
+The value of TIMEFORMAT is a string with `%' escapes expanded in a
+fashion similar in spirit to printf(3). The manual page explains
+the meanings of the escape sequences in the format string.
+
+If TIMEFORMAT is not set, bash acts as if the following assignment had
+been performed:
+
+ TIMEFORMAT=$'\nreal\t%3lR\nuser\t%3lU\nsys\t%3lS'
+
+The POSIX.2 default time format (used by `time -p command') is
+
+ TIMEFORMAT=$'real %2R\nuser %2U\nsys %2S'
+
+The BSD /usr/bin/time format can be emulated with:
+
+ TIMEFORMAT=$'\t%1R real\t%1U user\t%1S sys'
+
+The System V /usr/bin/time format can be emulated with:
+
+ TIMEFORMAT=$'\nreal\t%1R\nuser\t%1U\nsys\t%1S'
+
+The ksh format can be emulated with:
+
+ TIMEFORMAT=$'\nreal\t%2lR\nuser\t%2lU\nsys\t%2lS'
+
+G5) How do I get the current directory into my prompt?
+
+Bash provides a number of backslash-escape sequences which are expanded
+when the prompt string (PS1 or PS2) is displayed. The full list is in
+the manual page.
+
+The \w expansion gives the full pathname of the current directory, with
+a tilde (`~') substituted for the current value of $HOME. The \W
+expansion gives the basename of the current directory. To put the full
+pathname of the current directory into the path without any tilde
+subsitution, use $PWD. Here are some examples:
+
+ PS1='\w$ ' # current directory with tilde
+ PS1='\W$ ' # basename of current directory
+ PS1='$PWD$ ' # full pathname of current directory
+
+The single quotes are important in the final example to prevent $PWD from
+being expanded when the assignment to PS1 is performed.
+
+G6) How can I rename "*.foo" to "*.bar"?
+
+Use the pattern removal functionality described in D3. The following `for'
+loop will do the trick:
+
+ for f in *.foo; do
+ mv $f ${f%foo}bar
+ done
+
+G7) How can I translate a filename from uppercase to lowercase?
+
+The script examples/functions/lowercase, originally written by John DuBois,
+will do the trick. The converse is left as an exercise.
+
+G8) How can I write a filename expansion (globbing) pattern that will match
+ all files in the current directory except "." and ".."?
+
+You must have set the `extglob' shell option using `shopt -s extglob' to use
+this:
+
+ echo .!(.|) *
+
+A solution that works without extended globbing is given in the Unix Shell
+FAQ, posted periodically to comp.unix.shell.
+
+Section H: Where do I go from here?
+
+H1) How do I report bugs in bash, and where should I look for fixes and
+ advice?
+
+Use the `bashbug' script to report bugs. It is built and
+installed at the same time as bash. It provides a standard
+template for reporting a problem and automatically includes
+information about your configuration and build environment.
+
+`bashbug' sends its reports to bug-bash@gnu.org, which
+is a large mailing list gatewayed to the usenet newsgroup gnu.bash.bug.
+
+Bug fixes, answers to questions, and announcements of new releases
+are all posted to gnu.bash.bug. Discussions concerning bash features
+and problems also take place there.
+
+To reach the bash maintainers directly, send mail to
+bash-maintainers@gnu.org.
+
+H2) What kind of bash documentation is there?
+
+First, look in the doc directory in the bash distribution. It should
+contain at least the following files:
+
+bash.1 an extensive, thorough Unix-style manual page
+builtins.1 a manual page covering just bash builtin commands
+bashref.texi a reference manual in GNU tex`info format
+bashref.info an info version of the reference manual
+FAQ this file
+article.ms text of an article written for The Linux Journal
+readline.3 a man page describing readline
+
+Postscript, HTML, and ASCII files created from the above source are
+available in the documentation distribution.
+
+There is additional documentation available for anonymous FTP from host
+ftp.cwru.edu in the `pub/bash' directory.
+
+Cameron Newham and Bill Rosenblatt have written a book on bash, published
+by O'Reilly and Associates. The book is based on Bill Rosenblatt's Korn
+Shell book. The title is ``Learning the Bash Shell'', and the ISBN number
+is 1-56592-147-X. Look for it in fine bookstores near you. This book
+covers bash-1.14, but has an appendix describing some of the new features
+in bash-2.0.
+
+A second edition of this book is available, published in January, 1998.
+The ISBN number is 1-56592-347-2. Look for it in the same fine bookstores
+or on the web.
+
+The GNU Bash Reference Manual has been published as a printed book by
+Network Theory Ltd (Paperback, ISBN: 0-9541617-7-7, Feb 2003). It covers
+bash-2.0 and is available from most online bookstores (see
+http://www.network-theory.co.uk/bash/manual/ for details). The publisher
+will donate $1 to the Free Software Foundation for each copy sold.
+
+H3) What's coming in future versions?
+
+These are features I hope to include in a future version of bash.
+
+a better bash debugger (a minimally-tested version is included with bash-2.05b)
+associative arrays
+co-processes, but with a new-style syntax that looks like function declaration
+
+H4) What's on the bash `wish list' for future versions?
+
+These are features that may or may not appear in a future version of bash.
+
+breaking some of the shell functionality into embeddable libraries
+a module system like zsh's, using dynamic loading like builtins
+better internationalization using GNU `gettext'
+date-stamped command history
+a bash programmer's guide with a chapter on creating loadable builtins
+a better loadable interface to perl with access to the shell builtins and
+ variables (contributions gratefully accepted)
+ksh93-like `nameref' variables
+ksh93-like `+=' variable assignment operator
+ksh93-like `xx.yy' variables (including some of the .sh.* variables) and
+ associated disipline functions
+Some of the new ksh93 pattern matching operators, like backreferencing
+
+H5) When will the next release appear?
+
+The next version will appear sometime in 2002. Never make predictions.
+
+
+This document is Copyright 1995-2003 by Chester Ramey.
+
+Permission is hereby granted, without written agreement and
+without license or royalty fees, to use, copy, and distribute
+this document for any purpose, provided that the above copyright
+notice appears in all copies of this document and that the
+contents of this document remain unaltered.
.\" Case Western Reserve University
.\" chet.ramey@case.edu
.\"
-.\" Last Change: Fri Nov 28 18:21:13 EST 2014
+.\" Last Change: Sat Dec 20 13:51:56 EST 2014
.\"
.\" bash_builtins, strip all but Built-Ins section
.if \n(zZ=1 .ig zZ
.if \n(zY=1 .ig zY
-.TH BASH 1 "2014 November 28" "GNU Bash 4.3"
+.TH BASH 1 "2014 December 20" "GNU Bash 4.3"
.\"
.\" There's some problem with having a `@'
.\" in a tagged paragraph with the BSD man macros.
.PD
.PP
If the first character of \fIparameter\fP is an exclamation point (\fB!\fP),
+and \fIparameter\fP is not a \fInameref\fP,
it introduces a level of variable indirection.
\fBBash\fP uses the value of the variable formed from the rest of
\fIparameter\fP as the name of the variable; this variable is then
expanded and that value is used in the rest of the substitution, rather
than the value of \fIparameter\fP itself.
This is known as \fIindirect expansion\fP.
+If \fIparameter\fP is a nameref, this expands to the name of the
+variable referenced by \fIparameter\fP instead of performing the
+complete indirect expansion.
The exceptions to this are the expansions of ${\fB!\fP\fIprefix\fP\fB*\fP} and
${\fB!\fP\fIname\fP[\fI@\fP]} described below.
The exclamation point must immediately follow the left brace in order to
--- /dev/null
+.\"
+.\" MAN PAGE COMMENTS to
+.\"
+.\" Chet Ramey
+.\" Case Western Reserve University
+.\" chet.ramey@case.edu
+.\"
+.\" Last Change: Fri Nov 28 18:21:13 EST 2014
+.\"
+.\" bash_builtins, strip all but Built-Ins section
+.if \n(zZ=1 .ig zZ
+.if \n(zY=1 .ig zY
+.TH BASH 1 "2014 November 28" "GNU Bash 4.3"
+.\"
+.\" There's some problem with having a `@'
+.\" in a tagged paragraph with the BSD man macros.
+.\" It has to do with `@' appearing in the }1 macro.
+.\" This is a problem on 4.3 BSD and Ultrix, but Sun
+.\" appears to have fixed it.
+.\" If you're seeing the characters
+.\" `@u-3p' appearing before the lines reading
+.\" `possible-hostname-completions
+.\" and `complete-hostname' down in READLINE,
+.\" then uncomment this redefinition.
+.\"
+.de }1
+.ds ]X \&\\*(]B\\
+.nr )E 0
+.if !"\\$1"" .nr )I \\$1n
+.}f
+.ll \\n(LLu
+.in \\n()Ru+\\n(INu+\\n()Iu
+.ti \\n(INu
+.ie !\\n()Iu+\\n()Ru-\w\a\\*(]X\au-3p \{\\*(]X
+.br\}
+.el \\*(]X\h\a|\\n()Iu+\\n()Ru\a\c
+.}f
+..
+.\"
+.\" File Name macro. This used to be `.PN', for Path Name,
+.\" but Sun doesn't seem to like that very much.
+.\"
+.de FN
+\fI\|\\$1\|\fP
+..
+.SH NAME
+bash \- GNU Bourne-Again SHell
+.SH SYNOPSIS
+.B bash
+[options]
+[command_string | file]
+.SH COPYRIGHT
+.if n Bash is Copyright (C) 1989-2014 by the Free Software Foundation, Inc.
+.if t Bash is Copyright \(co 1989-2014 by the Free Software Foundation, Inc.
+.SH DESCRIPTION
+.B Bash
+is an \fBsh\fR-compatible command language interpreter that
+executes commands read from the standard input or from a file.
+.B Bash
+also incorporates useful features from the \fIKorn\fP and \fIC\fP
+shells (\fBksh\fP and \fBcsh\fP).
+.PP
+.B Bash
+is intended to be a conformant implementation of the
+Shell and Utilities portion of the IEEE POSIX specification
+(IEEE Standard 1003.1).
+.B Bash
+can be configured to be POSIX-conformant by default.
+.SH OPTIONS
+All of the single-character shell options documented in the
+description of the \fBset\fR builtin command can be used as options
+when the shell is invoked.
+In addition, \fBbash\fR
+interprets the following options when it is invoked:
+.PP
+.PD 0
+.TP 10
+.B \-c
+If the
+.B \-c
+option is present, then commands are read from the first non-option argument
+.IR command_string .
+If there are arguments after the
+.IR command_string ,
+the first argument is assigned to
+.B $0
+and any remaining arguments are assigned to the positional parameters.
+The assignment to
+.B $0
+sets the name of the shell, which is used in warning and error messages.
+.TP
+.B \-i
+If the
+.B \-i
+option is present, the shell is
+.IR interactive .
+.TP
+.B \-l
+Make
+.B bash
+act as if it had been invoked as a login shell (see
+.SM
+.B INVOCATION
+below).
+.TP
+.B \-r
+If the
+.B \-r
+option is present, the shell becomes
+.I restricted
+(see
+.SM
+.B "RESTRICTED SHELL"
+below).
+.TP
+.B \-s
+If the
+.B \-s
+option is present, or if no arguments remain after option
+processing, then commands are read from the standard input.
+This option allows the positional parameters to be set
+when invoking an interactive shell.
+.TP
+.B \-D
+A list of all double-quoted strings preceded by \fB$\fP
+is printed on the standard output.
+These are the strings that
+are subject to language translation when the current locale
+is not \fBC\fP or \fBPOSIX\fP.
+This implies the \fB\-n\fP option; no commands will be executed.
+.TP
+.B [\-+]O [\fIshopt_option\fP]
+\fIshopt_option\fP is one of the shell options accepted by the
+\fBshopt\fP builtin (see
+.SM
+.B SHELL BUILTIN COMMANDS
+below).
+If \fIshopt_option\fP is present, \fB\-O\fP sets the value of that option;
+\fB+O\fP unsets it.
+If \fIshopt_option\fP is not supplied, the names and values of the shell
+options accepted by \fBshopt\fP are printed on the standard output.
+If the invocation option is \fB+O\fP, the output is displayed in a format
+that may be reused as input.
+.TP
+.B \-\-
+A
+.B \-\-
+signals the end of options and disables further option processing.
+Any arguments after the
+.B \-\-
+are treated as filenames and arguments. An argument of
+.B \-
+is equivalent to \fB\-\-\fP.
+.PD
+.PP
+.B Bash
+also interprets a number of multi-character options.
+These options must appear on the command line before the
+single-character options to be recognized.
+.PP
+.PD 0
+.TP
+.B \-\-debugger
+Arrange for the debugger profile to be executed before the shell
+starts.
+Turns on extended debugging mode (see the description of the
+.B extdebug
+option to the
+.B shopt
+builtin below).
+.TP
+.B \-\-dump\-po\-strings
+Equivalent to \fB\-D\fP, but the output is in the GNU \fIgettext\fP
+\fBpo\fP (portable object) file format.
+.TP
+.B \-\-dump\-strings
+Equivalent to \fB\-D\fP.
+.TP
+.B \-\-help
+Display a usage message on standard output and exit successfully.
+.TP
+\fB\-\-init\-file\fP \fIfile\fP
+.PD 0
+.TP
+\fB\-\-rcfile\fP \fIfile\fP
+.PD
+Execute commands from
+.I file
+instead of the standard personal initialization file
+.I ~/.bashrc
+if the shell is interactive (see
+.SM
+.B INVOCATION
+below).
+.TP
+.B \-\-login
+Equivalent to \fB\-l\fP.
+.TP
+.B \-\-noediting
+Do not use the GNU
+.B readline
+library to read command lines when the shell is interactive.
+.TP
+.B \-\-noprofile
+Do not read either the system-wide startup file
+.FN /etc/profile
+or any of the personal initialization files
+.IR ~/.bash_profile ,
+.IR ~/.bash_login ,
+or
+.IR ~/.profile .
+By default,
+.B bash
+reads these files when it is invoked as a login shell (see
+.SM
+.B INVOCATION
+below).
+.TP
+.B \-\-norc
+Do not read and execute the personal initialization file
+.I ~/.bashrc
+if the shell is interactive.
+This option is on by default if the shell is invoked as
+.BR sh .
+.TP
+.B \-\-posix
+Change the behavior of \fBbash\fP where the default operation differs
+from the POSIX standard to match the standard (\fIposix mode\fP).
+See
+.SM
+.B "SEE ALSO"
+below for a reference to a document that details how posix mode affects
+bash's behavior.
+.TP
+.B \-\-restricted
+The shell becomes restricted (see
+.SM
+.B "RESTRICTED SHELL"
+below).
+.TP
+.B \-\-verbose
+Equivalent to \fB\-v\fP.
+.TP
+.B \-\-version
+Show version information for this instance of
+.B bash
+on the standard output and exit successfully.
+.PD
+.SH ARGUMENTS
+If arguments remain after option processing, and neither the
+.B \-c
+nor the
+.B \-s
+option has been supplied, the first argument is assumed to
+be the name of a file containing shell commands.
+If
+.B bash
+is invoked in this fashion,
+.B $0
+is set to the name of the file, and the positional parameters
+are set to the remaining arguments.
+.B Bash
+reads and executes commands from this file, then exits.
+\fBBash\fP's exit status is the exit status of the last command
+executed in the script.
+If no commands are executed, the exit status is 0.
+An attempt is first made to open the file in the current directory, and,
+if no file is found, then the shell searches the directories in
+.SM
+.B PATH
+for the script.
+.SH INVOCATION
+A \fIlogin shell\fP is one whose first character of argument zero is a
+.BR \- ,
+or one started with the
+.B \-\-login
+option.
+.PP
+An \fIinteractive\fP shell is one started without non-option arguments
+and without the
+.B \-c
+option
+whose standard input and error are
+both connected to terminals (as determined by
+.IR isatty (3)),
+or one started with the
+.B \-i
+option.
+.SM
+.B PS1
+is set and
+.B $\-
+includes
+.B i
+if
+.B bash
+is interactive,
+allowing a shell script or a startup file to test this state.
+.PP
+The following paragraphs describe how
+.B bash
+executes its startup files.
+If any of the files exist but cannot be read,
+.B bash
+reports an error.
+Tildes are expanded in filenames as described below under
+.B "Tilde Expansion"
+in the
+.SM
+.B EXPANSION
+section.
+.PP
+When
+.B bash
+is invoked as an interactive login shell, or as a non-interactive shell
+with the \fB\-\-login\fP option, it first reads and
+executes commands from the file \fI/etc/profile\fP, if that
+file exists.
+After reading that file, it looks for \fI~/.bash_profile\fP,
+\fI~/.bash_login\fP, and \fI~/.profile\fP, in that order, and reads
+and executes commands from the first one that exists and is readable.
+The
+.B \-\-noprofile
+option may be used when the shell is started to inhibit this behavior.
+.PP
+When a login shell exits,
+.B bash
+reads and executes commands from the file \fI~/.bash_logout\fP, if it
+exists.
+.PP
+When an interactive shell that is not a login shell is started,
+.B bash
+reads and executes commands from \fI~/.bashrc\fP, if that file exists.
+This may be inhibited by using the
+.B \-\-norc
+option.
+The \fB\-\-rcfile\fP \fIfile\fP option will force
+.B bash
+to read and execute commands from \fIfile\fP instead of \fI~/.bashrc\fP.
+.PP
+When
+.B bash
+is started non-interactively, to run a shell script, for example, it
+looks for the variable
+.SM
+.B BASH_ENV
+in the environment, expands its value if it appears there, and uses the
+expanded value as the name of a file to read and execute.
+.B Bash
+behaves as if the following command were executed:
+.sp .5
+.RS
+.if t \f(CWif [ \-n "$BASH_ENV" ]; then . "$BASH_ENV"; fi\fP
+.if n if [ \-n "$BASH_ENV" ]; then . "$BASH_ENV"; fi
+.RE
+.sp .5
+but the value of the
+.SM
+.B PATH
+variable is not used to search for the filename.
+.PP
+If
+.B bash
+is invoked with the name
+.BR sh ,
+it tries to mimic the startup behavior of historical versions of
+.B sh
+as closely as possible,
+while conforming to the POSIX standard as well.
+When invoked as an interactive login shell, or a non-interactive
+shell with the \fB\-\-login\fP option, it first attempts to
+read and execute commands from
+.I /etc/profile
+and
+.IR ~/.profile ,
+in that order.
+The
+.B \-\-noprofile
+option may be used to inhibit this behavior.
+When invoked as an interactive shell with the name
+.BR sh ,
+.B bash
+looks for the variable
+.SM
+.BR ENV ,
+expands its value if it is defined, and uses the
+expanded value as the name of a file to read and execute.
+Since a shell invoked as
+.B sh
+does not attempt to read and execute commands from any other startup
+files, the
+.B \-\-rcfile
+option has no effect.
+A non-interactive shell invoked with the name
+.B sh
+does not attempt to read any other startup files.
+When invoked as
+.BR sh ,
+.B bash
+enters
+.I posix
+mode after the startup files are read.
+.PP
+When
+.B bash
+is started in
+.I posix
+mode, as with the
+.B \-\-posix
+command line option, it follows the POSIX standard for startup files.
+In this mode, interactive shells expand the
+.SM
+.B ENV
+variable and commands are read and executed from the file
+whose name is the expanded value.
+No other startup files are read.
+.PP
+.B Bash
+attempts to determine when it is being run with its standard input
+connected to a network connection, as when executed by the remote shell
+daemon, usually \fIrshd\fP, or the secure shell daemon \fIsshd\fP.
+If
+.B bash
+determines it is being run in this fashion, it reads and executes
+commands from \fI~/.bashrc\fP, if that file exists and is readable.
+It will not do this if invoked as \fBsh\fP.
+The
+.B \-\-norc
+option may be used to inhibit this behavior, and the
+.B \-\-rcfile
+option may be used to force another file to be read, but neither
+\fIrshd\fP nor \fIsshd\fP generally invoke the shell with those options
+or allow them to be specified.
+.PP
+If the shell is started with the effective user (group) id not equal to the
+real user (group) id, and the \fB\-p\fP option is not supplied, no startup
+files are read, shell functions are not inherited from the environment, the
+.SM
+.BR SHELLOPTS ,
+.SM
+.BR BASHOPTS ,
+.SM
+.BR CDPATH ,
+and
+.SM
+.B GLOBIGNORE
+variables, if they appear in the environment, are ignored,
+and the effective user id is set to the real user id.
+If the \fB\-p\fP option is supplied at invocation, the startup behavior is
+the same, but the effective user id is not reset.
+.SH DEFINITIONS
+.PP
+The following definitions are used throughout the rest of this
+document.
+.PD 0
+.TP
+.B blank
+A space or tab.
+.TP
+.B word
+A sequence of characters considered as a single unit by the shell.
+Also known as a
+.BR token .
+.TP
+.B name
+A
+.I word
+consisting only of alphanumeric characters and underscores, and
+beginning with an alphabetic character or an underscore. Also
+referred to as an
+.BR identifier .
+.TP
+.B metacharacter
+A character that, when unquoted, separates words. One of the following:
+.br
+.RS
+.PP
+.if t \fB| & ; ( ) < > space tab\fP
+.if n \fB| & ; ( ) < > space tab\fP
+.RE
+.PP
+.TP
+.B control operator
+A \fItoken\fP that performs a control function. It is one of the following
+symbols:
+.RS
+.PP
+.if t \fB|| & && ; ;; ( ) | |& <newline>\fP
+.if n \fB|| & && ; ;; ( ) | |& <newline>\fP
+.RE
+.PD
+.SH "RESERVED WORDS"
+\fIReserved words\fP are words that have a special meaning to the shell.
+The following words are recognized as reserved when unquoted and either
+the first word of a simple command (see
+.SM
+.B SHELL GRAMMAR
+below) or the third word of a
+.B case
+or
+.B for
+command:
+.if t .RS
+.PP
+.B
+.if n ! case coproc do done elif else esac fi for function if in select then until while { } time [[ ]]
+.if t ! case coproc do done elif else esac fi for function if in select then until while { } time [[ ]]
+.if t .RE
+.SH "SHELL GRAMMAR"
+.SS Simple Commands
+.PP
+A \fIsimple command\fP is a sequence of optional variable assignments
+followed by \fBblank\fP-separated words and redirections, and
+terminated by a \fIcontrol operator\fP. The first word
+specifies the command to be executed, and is passed as argument zero.
+The remaining words are passed as arguments to the invoked command.
+.PP
+The return value of a \fIsimple command\fP is its exit status, or
+128+\fIn\^\fP if the command is terminated by signal
+.IR n .
+.SS Pipelines
+.PP
+A \fIpipeline\fP is a sequence of one or more commands separated by
+one of the control operators
+.B |
+or \fB|&\fP.
+The format for a pipeline is:
+.RS
+.PP
+[\fBtime\fP [\fB\-p\fP]] [ ! ] \fIcommand\fP [ [\fB|\fP\(bv\fB|&\fP] \fIcommand2\fP ... ]
+.RE
+.PP
+The standard output of
+.I command
+is connected via a pipe to the standard input of
+.IR command2 .
+This connection is performed before any redirections specified by the
+command (see
+.SM
+.B REDIRECTION
+below).
+If \fB|&\fP is used, \fIcommand\fP's standard error, in addition to its
+standard output, is connected to
+\fIcommand2\fP's standard input through the pipe;
+it is shorthand for \fB2>&1 |\fP.
+This implicit redirection of the standard error to the standard output is
+performed after any redirections specified by the command.
+.PP
+The return status of a pipeline is the exit status of the last
+command, unless the \fBpipefail\fP option is enabled.
+If \fBpipefail\fP is enabled, the pipeline's return status is the
+value of the last (rightmost) command to exit with a non-zero status,
+or zero if all commands exit successfully.
+If the reserved word
+.B !
+precedes a pipeline, the exit status of that pipeline is the logical
+negation of the exit status as described above.
+The shell waits for all commands in the pipeline to
+terminate before returning a value.
+.PP
+If the
+.B time
+reserved word precedes a pipeline, the elapsed as well as user and
+system time consumed by its execution are reported when the pipeline
+terminates.
+The \fB\-p\fP option changes the output format to that specified by POSIX.
+When the shell is in \fIposix mode\fP, it does not recognize
+\fBtime\fP as a reserved word if the next token begins with a `-'.
+The
+.SM
+.B TIMEFORMAT
+variable may be set to a format string that specifies how the timing
+information should be displayed; see the description of
+.SM
+.B TIMEFORMAT
+under
+.B "Shell Variables"
+below.
+.PP
+When the shell is in \fIposix mode\fP, \fBtime\fP
+may be followed by a newline. In this case, the shell displays the
+total user and system time consumed by the shell and its children.
+The
+.SM
+.B TIMEFORMAT
+variable may be used to specify the format of
+the time information.
+.PP
+Each command in a pipeline is executed as a separate process (i.e., in a
+subshell).
+.SS Lists
+.PP
+A \fIlist\fP is a sequence of one or more pipelines separated by one
+of the operators
+.BR ; ,
+.BR & ,
+.BR && ,
+or
+.BR || ,
+and optionally terminated by one of
+.BR ; ,
+.BR & ,
+or
+.BR <newline> .
+.PP
+Of these list operators,
+.B &&
+and
+.B ||
+have equal precedence, followed by
+.B ;
+and
+.BR & ,
+which have equal precedence.
+.PP
+A sequence of one or more newlines may appear in a \fIlist\fP instead
+of a semicolon to delimit commands.
+.PP
+If a command is terminated by the control operator
+.BR & ,
+the shell executes the command in the \fIbackground\fP
+in a subshell. The shell does not wait for the command to
+finish, and the return status is 0. Commands separated by a
+.B ;
+are executed sequentially; the shell waits for each
+command to terminate in turn. The return status is the
+exit status of the last command executed.
+.PP
+AND and OR lists are sequences of one of more pipelines separated by the
+\fB&&\fP and \fB||\fP control operators, respectively.
+AND and OR lists are executed with left associativity.
+An AND list has the form
+.RS
+.PP
+\fIcommand1\fP \fB&&\fP \fIcommand2\fP
+.RE
+.PP
+.I command2
+is executed if, and only if,
+.I command1
+returns an exit status of zero.
+.PP
+An OR list has the form
+.RS
+.PP
+\fIcommand1\fP \fB||\fP \fIcommand2\fP
+.PP
+.RE
+.PP
+.I command2
+is executed if and only if
+.I command1
+returns a non-zero exit status.
+The return status of
+AND and OR lists is the exit status of the last command
+executed in the list.
+.SS Compound Commands
+.PP
+A \fIcompound command\fP is one of the following.
+In most cases a \fIlist\fP in a command's description may be separated from
+the rest of the command by one or more newlines, and may be followed by a
+newline in place of a semicolon.
+.TP
+(\fIlist\fP)
+\fIlist\fP is executed in a subshell environment (see
+.SM
+\fBCOMMAND EXECUTION ENVIRONMENT\fP
+below).
+Variable assignments and builtin
+commands that affect the shell's environment do not remain in effect
+after the command completes. The return status is the exit status of
+\fIlist\fP.
+.TP
+{ \fIlist\fP; }
+\fIlist\fP is simply executed in the current shell environment.
+\fIlist\fP must be terminated with a newline or semicolon.
+This is known as a \fIgroup command\fP.
+The return status is the exit status of
+\fIlist\fP.
+Note that unlike the metacharacters \fB(\fP and \fB)\fP, \fB{\fP and
+\fB}\fP are \fIreserved words\fP and must occur where a reserved
+word is permitted to be recognized. Since they do not cause a word
+break, they must be separated from \fIlist\fP by whitespace or another
+shell metacharacter.
+.TP
+((\fIexpression\fP))
+The \fIexpression\fP is evaluated according to the rules described
+below under
+.SM
+.BR "ARITHMETIC EVALUATION" .
+If the value of the expression is non-zero, the return status is 0;
+otherwise the return status is 1. This is exactly equivalent to
+\fBlet "\fIexpression\fP"\fR.
+.TP
+\fB[[\fP \fIexpression\fP \fB]]\fP
+Return a status of 0 or 1 depending on the evaluation of
+the conditional expression \fIexpression\fP.
+Expressions are composed of the primaries described below under
+.SM
+.BR "CONDITIONAL EXPRESSIONS" .
+Word splitting and pathname expansion are not performed on the words
+between the \fB[[\fP and \fB]]\fP; tilde expansion,
+parameter and variable expansion,
+arithmetic expansion, command substitution, process
+substitution, and quote removal are performed.
+Conditional operators such as \fB\-f\fP must be unquoted to be recognized
+as primaries.
+.if t .sp 0.5
+.if n .sp 1
+When used with \fB[[\fP, the \fB<\fP and \fB>\fP operators sort
+lexicographically using the current locale.
+.if t .sp 0.5
+.if n .sp 1
+When the \fB==\fP and \fB!=\fP operators are used, the string to the
+right of the operator is considered a pattern and matched according
+to the rules described below under \fBPattern Matching\fP,
+as if the \fBextglob\fP shell option were enabled.
+The \fB=\fP operator is equivalent to \fB==\fP.
+If the
+.B nocasematch
+shell option is enabled, the match is performed without regard to the case
+of alphabetic characters.
+The return value is 0 if the string matches (\fB==\fP) or does not match
+(\fB!=\fP) the pattern, and 1 otherwise.
+Any part of the pattern may be quoted to force the quoted portion
+to be matched as a string.
+.if t .sp 0.5
+.if n .sp 1
+An additional binary operator, \fB=~\fP, is available, with the same
+precedence as \fB==\fP and \fB!=\fP.
+When it is used, the string to the right of the operator is considered
+an extended regular expression and matched accordingly (as in \fIregex\fP(3)).
+The return value is 0 if the string matches
+the pattern, and 1 otherwise.
+If the regular expression is syntactically incorrect, the conditional
+expression's return value is 2.
+If the
+.B nocasematch
+shell option is enabled, the match is performed without regard to the case
+of alphabetic characters.
+Any part of the pattern may be quoted to force the quoted portion
+to be matched as a string.
+Bracket expressions in regular expressions must be treated carefully,
+since normal quoting characters lose their meanings between brackets.
+If the pattern is stored in a shell variable, quoting the variable
+expansion forces the entire pattern to be matched as a string.
+Substrings matched by parenthesized subexpressions within the regular
+expression are saved in the array variable
+.SM
+.BR BASH_REMATCH .
+The element of
+.SM
+.B BASH_REMATCH
+with index 0 is the portion of the string
+matching the entire regular expression.
+The element of
+.SM
+.B BASH_REMATCH
+with index \fIn\fP is the portion of the
+string matching the \fIn\fPth parenthesized subexpression.
+.if t .sp 0.5
+.if n .sp 1
+Expressions may be combined using the following operators, listed
+in decreasing order of precedence:
+.if t .sp 0.5
+.if n .sp 1
+.RS
+.PD 0
+.TP
+.B ( \fIexpression\fP )
+Returns the value of \fIexpression\fP.
+This may be used to override the normal precedence of operators.
+.TP
+.B ! \fIexpression\fP
+True if
+.I expression
+is false.
+.TP
+\fIexpression1\fP \fB&&\fP \fIexpression2\fP
+True if both
+.I expression1
+and
+.I expression2
+are true.
+.TP
+\fIexpression1\fP \fB||\fP \fIexpression2\fP
+True if either
+.I expression1
+or
+.I expression2
+is true.
+.PD
+.LP
+The \fB&&\fP and \fB||\fP
+operators do not evaluate \fIexpression2\fP if the value of
+\fIexpression1\fP is sufficient to determine the return value of
+the entire conditional expression.
+.RE
+.TP
+\fBfor\fP \fIname\fP [ [ \fBin\fP [ \fIword ...\fP ] ] ; ] \fBdo\fP \fIlist\fP ; \fBdone\fP
+The list of words following \fBin\fP is expanded, generating a list
+of items.
+The variable \fIname\fP is set to each element of this list
+in turn, and \fIlist\fP is executed each time.
+If the \fBin\fP \fIword\fP is omitted, the \fBfor\fP command executes
+\fIlist\fP once for each positional parameter that is set (see
+.SM
+.B PARAMETERS
+below).
+The return status is the exit status of the last command that executes.
+If the expansion of the items following \fBin\fP results in an empty
+list, no commands are executed, and the return status is 0.
+.TP
+\fBfor\fP (( \fIexpr1\fP ; \fIexpr2\fP ; \fIexpr3\fP )) ; \fBdo\fP \fIlist\fP ; \fBdone\fP
+First, the arithmetic expression \fIexpr1\fP is evaluated according
+to the rules described below under
+.SM
+.BR "ARITHMETIC EVALUATION" .
+The arithmetic expression \fIexpr2\fP is then evaluated repeatedly
+until it evaluates to zero.
+Each time \fIexpr2\fP evaluates to a non-zero value, \fIlist\fP is
+executed and the arithmetic expression \fIexpr3\fP is evaluated.
+If any expression is omitted, it behaves as if it evaluates to 1.
+The return value is the exit status of the last command in \fIlist\fP
+that is executed, or false if any of the expressions is invalid.
+.TP
+\fBselect\fP \fIname\fP [ \fBin\fP \fIword\fP ] ; \fBdo\fP \fIlist\fP ; \fBdone\fP
+The list of words following \fBin\fP is expanded, generating a list
+of items. The set of expanded words is printed on the standard
+error, each preceded by a number. If the \fBin\fP
+\fIword\fP is omitted, the positional parameters are printed (see
+.SM
+.B PARAMETERS
+below). The
+.SM
+.B PS3
+prompt is then displayed and a line read from the standard input.
+If the line consists of a number corresponding to one of
+the displayed words, then the value of
+.I name
+is set to that word. If the line is empty, the words and prompt
+are displayed again. If EOF is read, the command completes. Any
+other value read causes
+.I name
+to be set to null. The line read is saved in the variable
+.SM
+.BR REPLY .
+The
+.I list
+is executed after each selection until a
+.B break
+command is executed.
+The exit status of
+.B select
+is the exit status of the last command executed in
+.IR list ,
+or zero if no commands were executed.
+.TP
+\fBcase\fP \fIword\fP \fBin\fP [ [(] \fIpattern\fP [ \fB|\fP \fIpattern\fP ] \
+... ) \fIlist\fP ;; ] ... \fBesac\fP
+A \fBcase\fP command first expands \fIword\fP, and tries to match
+it against each \fIpattern\fP in turn, using the same matching rules
+as for pathname expansion (see
+.B Pathname Expansion
+below).
+The \fIword\fP is expanded using tilde
+expansion, parameter and variable expansion, arithmetic expansion,
+command substitution, process substitution and quote removal.
+Each \fIpattern\fP examined is expanded using tilde
+expansion, parameter and variable expansion, arithmetic expansion,
+command substitution, and process substitution.
+If the
+.B nocasematch
+shell option is enabled, the match is performed without regard to the case
+of alphabetic characters.
+When a match is found, the corresponding \fIlist\fP is executed.
+If the \fB;;\fP operator is used, no subsequent matches are attempted after
+the first pattern match.
+Using \fB;&\fP in place of \fB;;\fP causes execution to continue with
+the \fIlist\fP associated with the next set of patterns.
+Using \fB;;&\fP in place of \fB;;\fP causes the shell to test the next
+pattern list in the statement, if any, and execute any associated \fIlist\fP
+on a successful match.
+The exit status is zero if no
+pattern matches. Otherwise, it is the exit status of the
+last command executed in \fIlist\fP.
+.TP
+\fBif\fP \fIlist\fP; \fBthen\fP \fIlist\fP; \
+[ \fBelif\fP \fIlist\fP; \fBthen\fP \fIlist\fP; ] ... \
+[ \fBelse\fP \fIlist\fP; ] \fBfi\fP
+The
+.B if
+.I list
+is executed. If its exit status is zero, the
+\fBthen\fP \fIlist\fP is executed. Otherwise, each \fBelif\fP
+\fIlist\fP is executed in turn, and if its exit status is zero,
+the corresponding \fBthen\fP \fIlist\fP is executed and the
+command completes. Otherwise, the \fBelse\fP \fIlist\fP is
+executed, if present. The exit status is the exit status of the
+last command executed, or zero if no condition tested true.
+.TP
+\fBwhile\fP \fIlist-1\fP; \fBdo\fP \fIlist-2\fP; \fBdone\fP
+.PD 0
+.TP
+\fBuntil\fP \fIlist-1\fP; \fBdo\fP \fIlist-2\fP; \fBdone\fP
+.PD
+The \fBwhile\fP command continuously executes the list
+\fIlist-2\fP as long as the last command in the list \fIlist-1\fP returns
+an exit status of zero. The \fBuntil\fP command is identical
+to the \fBwhile\fP command, except that the test is negated;
+.I list-2
+is executed as long as the last command in
+.I list-1
+returns a non-zero exit status.
+The exit status of the \fBwhile\fP and \fBuntil\fP commands
+is the exit status
+of the last command executed in \fIlist-2\fP, or zero if
+none was executed.
+.SS Coprocesses
+.PP
+A \fIcoprocess\fP is a shell command preceded by the \fBcoproc\fP reserved
+word.
+A coprocess is executed asynchronously in a subshell, as if the command
+had been terminated with the \fB&\fP control operator, with a two-way pipe
+established between the executing shell and the coprocess.
+.PP
+The format for a coprocess is:
+.RS
+.PP
+\fBcoproc\fP [\fINAME\fP] \fIcommand\fP [\fIredirections\fP]
+.RE
+.PP
+This creates a coprocess named \fINAME\fP.
+If \fINAME\fP is not supplied, the default name is \fBCOPROC\fP.
+\fINAME\fP must not be supplied if \fIcommand\fP is a \fIsimple
+command\fP (see above); otherwise, it is interpreted as the first word
+of the simple command.
+When the coprocess is executed, the shell creates an array variable (see
+.B Arrays
+below) named \fINAME\fP in the context of the executing shell.
+The standard output of
+.I command
+is connected via a pipe to a file descriptor in the executing shell,
+and that file descriptor is assigned to \fINAME\fP[0].
+The standard input of
+.I command
+is connected via a pipe to a file descriptor in the executing shell,
+and that file descriptor is assigned to \fINAME\fP[1].
+This pipe is established before any redirections specified by the
+command (see
+.SM
+.B REDIRECTION
+below).
+The file descriptors can be utilized as arguments to shell commands
+and redirections using standard word expansions.
+The file descriptors are not available in subshells.
+The process ID of the shell spawned to execute the coprocess is
+available as the value of the variable \fINAME\fP_PID.
+The \fBwait\fP
+builtin command may be used to wait for the coprocess to terminate.
+.PP
+Since the coprocess is created as an asynchronous command,
+the \fBcoproc\fP command always returns success.
+The return status of a coprocess is the exit status of \fIcommand\fP.
+.SS Shell Function Definitions
+.PP
+A shell function is an object that is called like a simple command and
+executes a compound command with a new set of positional parameters.
+Shell functions are declared as follows:
+.TP
+\fIname\fP () \fIcompound\-command\fP [\fIredirection\fP]
+.PD 0
+.TP
+\fBfunction\fP \fIname\fP [()] \fIcompound\-command\fP [\fIredirection\fP]
+.PD
+This defines a function named \fIname\fP.
+The reserved word \fBfunction\fP is optional.
+If the \fBfunction\fP reserved word is supplied, the parentheses are optional.
+The \fIbody\fP of the function is the compound command
+.I compound\-command
+(see \fBCompound Commands\fP above).
+That command is usually a \fIlist\fP of commands between { and }, but
+may be any command listed under \fBCompound Commands\fP above,
+with one exception: If the \fBfunction\fP reserved word is used, but the
+parentheses are not supplied, the braces are required.
+\fIcompound\-command\fP is executed whenever \fIname\fP is specified as the
+name of a simple command.
+When in \fIposix mode\fP, \fIname\fP may not be the name of one of the
+POSIX \fIspecial builtins\fP.
+Any redirections (see
+.SM
+.B REDIRECTION
+below) specified when a function is defined are performed
+when the function is executed.
+The exit status of a function definition is zero unless a syntax error
+occurs or a readonly function with the same name already exists.
+When executed, the exit status of a function is the exit status of the
+last command executed in the body. (See
+.SM
+.B FUNCTIONS
+below.)
+.SH COMMENTS
+In a non-interactive shell, or an interactive shell in which the
+.B interactive_comments
+option to the
+.B shopt
+builtin is enabled (see
+.SM
+.B "SHELL BUILTIN COMMANDS"
+below), a word beginning with
+.B #
+causes that word and all remaining characters on that line to
+be ignored. An interactive shell without the
+.B interactive_comments
+option enabled does not allow comments. The
+.B interactive_comments
+option is on by default in interactive shells.
+.SH QUOTING
+\fIQuoting\fP is used to remove the special meaning of certain
+characters or words to the shell. Quoting can be used to
+disable special treatment for special characters, to prevent
+reserved words from being recognized as such, and to prevent
+parameter expansion.
+.PP
+Each of the \fImetacharacters\fP listed above under
+.SM
+.B DEFINITIONS
+has special meaning to the shell and must be quoted if it is to
+represent itself.
+.PP
+When the command history expansion facilities are being used
+(see
+.SM
+.B HISTORY EXPANSION
+below), the
+\fIhistory expansion\fP character, usually \fB!\fP, must be quoted
+to prevent history expansion.
+.PP
+There are three quoting mechanisms: the
+.IR "escape character" ,
+single quotes, and double quotes.
+.PP
+A non-quoted backslash (\fB\e\fP) is the
+.IR "escape character" .
+It preserves the literal value of the next character that follows,
+with the exception of <newline>. If a \fB\e\fP<newline> pair
+appears, and the backslash is not itself quoted, the \fB\e\fP<newline>
+is treated as a line continuation (that is, it is removed from the
+input stream and effectively ignored).
+.PP
+Enclosing characters in single quotes preserves the literal value
+of each character within the quotes. A single quote may not occur
+between single quotes, even when preceded by a backslash.
+.PP
+Enclosing characters in double quotes preserves the literal value
+of all characters within the quotes, with the exception of
+.BR $ ,
+.BR \` ,
+.BR \e ,
+and, when history expansion is enabled,
+.BR ! .
+The characters
+.B $
+and
+.B \`
+retain their special meaning within double quotes. The backslash
+retains its special meaning only when followed by one of the following
+characters:
+.BR $ ,
+.BR \` ,
+\^\fB"\fP\^,
+.BR \e ,
+or
+.BR <newline> .
+A double quote may be quoted within double quotes by preceding it with
+a backslash.
+If enabled, history expansion will be performed unless an
+.B !
+appearing in double quotes is escaped using a backslash.
+The backslash preceding the
+.B !
+is not removed.
+.PP
+The special parameters
+.B *
+and
+.B @
+have special meaning when in double
+quotes (see
+.SM
+.B PARAMETERS
+below).
+.PP
+Words of the form \fB$\fP\(aq\fIstring\fP\(aq are treated specially. The
+word expands to \fIstring\fP, with backslash-escaped characters replaced
+as specified by the ANSI C standard. Backslash escape sequences, if
+present, are decoded as follows:
+.RS
+.PD 0
+.TP
+.B \ea
+alert (bell)
+.TP
+.B \eb
+backspace
+.TP
+.B \ee
+.TP
+.B \eE
+an escape character
+.TP
+.B \ef
+form feed
+.TP
+.B \en
+new line
+.TP
+.B \er
+carriage return
+.TP
+.B \et
+horizontal tab
+.TP
+.B \ev
+vertical tab
+.TP
+.B \e\e
+backslash
+.TP
+.B \e\(aq
+single quote
+.TP
+.B \e\(dq
+double quote
+.TP
+.B \e\fInnn\fP
+the eight-bit character whose value is the octal value \fInnn\fP
+(one to three digits)
+.TP
+.B \ex\fIHH\fP
+the eight-bit character whose value is the hexadecimal value \fIHH\fP
+(one or two hex digits)
+.TP
+.B \eu\fIHHHH\fP
+the Unicode (ISO/IEC 10646) character whose value is the hexadecimal value
+\fIHHHH\fP (one to four hex digits)
+.TP
+.B \eU\fIHHHHHHHH\fP
+the Unicode (ISO/IEC 10646) character whose value is the hexadecimal value
+\fIHHHHHHHH\fP (one to eight hex digits)
+.TP
+.B \ec\fIx\fP
+a control-\fIx\fP character
+.PD
+.RE
+.LP
+The expanded result is single-quoted, as if the dollar sign had
+not been present.
+.PP
+A double-quoted string preceded by a dollar sign (\fB$\fP\(dq\fIstring\fP\(dq)
+will cause the string to be translated according to the current locale.
+If the current locale is \fBC\fP or \fBPOSIX\fP, the dollar sign
+is ignored.
+If the string is translated and replaced, the replacement is
+double-quoted.
+.SH PARAMETERS
+A
+.I parameter
+is an entity that stores values.
+It can be a
+.IR name ,
+a number, or one of the special characters listed below under
+.BR "Special Parameters" .
+A
+.I variable
+is a parameter denoted by a
+.IR name .
+A variable has a \fIvalue\fP and zero or more \fIattributes\fP.
+Attributes are assigned using the
+.B declare
+builtin command (see
+.B declare
+below in
+.SM
+.BR "SHELL BUILTIN COMMANDS" ).
+.PP
+A parameter is set if it has been assigned a value. The null string is
+a valid value. Once a variable is set, it may be unset only by using
+the
+.B unset
+builtin command (see
+.SM
+.B SHELL BUILTIN COMMANDS
+below).
+.PP
+A
+.I variable
+may be assigned to by a statement of the form
+.RS
+.PP
+\fIname\fP=[\fIvalue\fP]
+.RE
+.PP
+If
+.I value
+is not given, the variable is assigned the null string. All
+.I values
+undergo tilde expansion, parameter and variable expansion,
+command substitution, arithmetic expansion, and quote
+removal (see
+.SM
+.B EXPANSION
+below). If the variable has its
+.B integer
+attribute set, then
+.I value
+is evaluated as an arithmetic expression even if the $((...)) expansion is
+not used (see
+.B "Arithmetic Expansion"
+below).
+Word splitting is not performed, with the exception
+of \fB"$@"\fP as explained below under
+.BR "Special Parameters" .
+Pathname expansion is not performed.
+Assignment statements may also appear as arguments to the
+.BR alias ,
+.BR declare ,
+.BR typeset ,
+.BR export ,
+.BR readonly ,
+and
+.B local
+builtin commands (\fIdeclaration\fP commands).
+When in \fIposix mode\fP, these builtins may appear in a command after
+one or more instances of the \fBcommand\fP builtin and retain these
+assignment statement properties.
+.PP
+In the context where an assignment statement is assigning a value
+to a shell variable or array index, the += operator can be used to
+append to or add to the variable's previous value.
+This includes arguments to builtin commands such as \fBdeclare\fP that
+accept assignment statements (\fIdeclaration\fP commands).
+When += is applied to a variable for which the \fIinteger\fP attribute has been
+set, \fIvalue\fP is evaluated as an arithmetic expression and added to the
+variable's current value, which is also evaluated.
+When += is applied to an array variable using compound assignment (see
+.B Arrays
+below), the
+variable's value is not unset (as it is when using =), and new values are
+appended to the array beginning at one greater than the array's maximum index
+(for indexed arrays) or added as additional key\-value pairs in an
+associative array.
+When applied to a string-valued variable, \fIvalue\fP is expanded and
+appended to the variable's value.
+.PP
+A variable can be assigned the \fInameref\fP attribute using the
+\fB\-n\fP option to the \fBdeclare\fP or \fBlocal\fP builtin commands
+(see the descriptions of \fBdeclare\fP and \fBlocal\fP below)
+to create a \fInameref\fP, or a reference to another variable.
+This allows variables to be manipulated indirectly.
+Whenever the nameref variable is referenced, assigned to, unset, or has
+its attributes modified (other than the \fInameref\fP attribute itself), the
+operation is actually performed on the variable specified by the nameref
+variable's value.
+A nameref is commonly used within shell functions to refer to a variable
+whose name is passed as an argument to the function.
+For instance, if a variable name is passed to a shell function as its first
+argument, running
+.sp .5
+.RS
+.if t \f(CWdeclare -n ref=$1\fP
+.if n declare -n ref=$1
+.RE
+.sp .5
+inside the function creates a nameref variable \fBref\fP whose value is
+the variable name passed as the first argument.
+References and assignments to \fBref\fP, and changes to its attributes,
+are treated as references, assignments, and attribute modifications
+to the variable whose name was passed as \fB$1\fP.
+If the control variable in a \fBfor\fP loop has the nameref attribute,
+the list of words can be a list of shell variables, and a name reference
+will be established for each word in the list, in turn, when the loop is
+executed.
+Array variables cannot be given the \fBnameref\fP attribute.
+However, nameref variables can reference array variables and subscripted
+array variables.
+Namerefs can be unset using the \fB\-n\fP option to the \fBunset\fP builtin.
+Otherwise, if \fBunset\fP is executed with the name of a nameref variable
+as an argument, the variable referenced by the nameref variable will be unset.
+.SS Positional Parameters
+.PP
+A
+.I positional parameter
+is a parameter denoted by one or more
+digits, other than the single digit 0. Positional parameters are
+assigned from the shell's arguments when it is invoked,
+and may be reassigned using the
+.B set
+builtin command. Positional parameters may not be assigned to
+with assignment statements. The positional parameters are
+temporarily replaced when a shell function is executed (see
+.SM
+.B FUNCTIONS
+below).
+.PP
+When a positional parameter consisting of more than a single
+digit is expanded, it must be enclosed in braces (see
+.SM
+.B EXPANSION
+below).
+.SS Special Parameters
+.PP
+The shell treats several parameters specially. These parameters may
+only be referenced; assignment to them is not allowed.
+.PD 0
+.TP
+.B *
+Expands to the positional parameters, starting from one.
+When the expansion is not within double quotes, each positional parameter
+expands to a separate word.
+In contexts where it is performed, those words
+are subject to further word splitting and pathname expansion.
+When the expansion occurs within double quotes, it expands to a single word
+with the value of each parameter separated by the first character of the
+.SM
+.B IFS
+special variable. That is, "\fB$*\fP" is equivalent
+to "\fB$1\fP\fIc\fP\fB$2\fP\fIc\fP\fB...\fP", where
+.I c
+is the first character of the value of the
+.SM
+.B IFS
+variable. If
+.SM
+.B IFS
+is unset, the parameters are separated by spaces.
+If
+.SM
+.B IFS
+is null, the parameters are joined without intervening separators.
+.TP
+.B @
+Expands to the positional parameters, starting from one. When the
+expansion occurs within double quotes, each parameter expands to a
+separate word. That is, "\fB$@\fP" is equivalent to
+"\fB$1\fP" "\fB$2\fP" ...
+If the double-quoted expansion occurs within a word, the expansion of
+the first parameter is joined with the beginning part of the original
+word, and the expansion of the last parameter is joined with the last
+part of the original word.
+When there are no positional parameters, "\fB$@\fP" and
+.B $@
+expand to nothing (i.e., they are removed).
+.TP
+.B #
+Expands to the number of positional parameters in decimal.
+.TP
+.B ?
+Expands to the exit status of the most recently executed foreground
+pipeline.
+.TP
+.B \-
+Expands to the current option flags as specified upon invocation,
+by the
+.B set
+builtin command, or those set by the shell itself
+(such as the
+.B \-i
+option).
+.TP
+.B $
+Expands to the process ID of the shell. In a () subshell, it
+expands to the process ID of the current shell, not the
+subshell.
+.TP
+.B !
+Expands to the process ID of the job most recently placed into the
+background, whether executed as an asynchronous command or using
+the \fBbg\fP builtin (see
+.SM
+.B "JOB CONTROL"
+below).
+.TP
+.B 0
+Expands to the name of the shell or shell script. This is set at
+shell initialization. If
+.B bash
+is invoked with a file of commands,
+.B $0
+is set to the name of that file. If
+.B bash
+is started with the
+.B \-c
+option, then
+.B $0
+is set to the first argument after the string to be
+executed, if one is present. Otherwise, it is set
+to the filename used to invoke
+.BR bash ,
+as given by argument zero.
+.TP
+.B _
+At shell startup, set to the absolute pathname used to invoke the
+shell or shell script being executed as passed in the environment
+or argument list.
+Subsequently, expands to the last argument to the previous command,
+after expansion.
+Also set to the full pathname used to invoke each command executed
+and placed in the environment exported to that command.
+When checking mail, this parameter holds the name of the mail file
+currently being checked.
+.PD
+.SS Shell Variables
+.PP
+The following variables are set by the shell:
+.PP
+.PD 0
+.TP
+.B BASH
+Expands to the full filename used to invoke this instance of
+.BR bash .
+.TP
+.B BASHOPTS
+A colon-separated list of enabled shell options. Each word in
+the list is a valid argument for the
+.B \-s
+option to the
+.B shopt
+builtin command (see
+.SM
+.B "SHELL BUILTIN COMMANDS"
+below). The options appearing in
+.SM
+.B BASHOPTS
+are those reported as
+.I on
+by \fBshopt\fP.
+If this variable is in the environment when
+.B bash
+starts up, each shell option in the list will be enabled before
+reading any startup files.
+This variable is read-only.
+.TP
+.B BASHPID
+Expands to the process ID of the current \fBbash\fP process.
+This differs from \fB$$\fP under certain circumstances, such as subshells
+that do not require \fBbash\fP to be re-initialized.
+.TP
+.B BASH_ALIASES
+An associative array variable whose members correspond to the internal
+list of aliases as maintained by the \fBalias\fP builtin.
+Elements added to this array appear in the alias list; unsetting array
+elements cause aliases to be removed from the alias list.
+.TP
+.B BASH_ARGC
+An array variable whose values are the number of parameters in each
+frame of the current \fBbash\fP execution call stack.
+The number of
+parameters to the current subroutine (shell function or script executed
+with \fB.\fP or \fBsource\fP) is at the top of the stack.
+When a subroutine is executed, the number of parameters passed is pushed onto
+.SM
+.BR BASH_ARGC .
+The shell sets
+.SM
+.B BASH_ARGC
+only when in extended debugging mode (see the description of the
+.B extdebug
+option to the
+.B shopt
+builtin below)
+.TP
+.B BASH_ARGV
+An array variable containing all of the parameters in the current \fBbash\fP
+execution call stack. The final parameter of the last subroutine call
+is at the top of the stack; the first parameter of the initial call is
+at the bottom. When a subroutine is executed, the parameters supplied
+are pushed onto
+.SM
+.BR BASH_ARGV .
+The shell sets
+.SM
+.B BASH_ARGV
+only when in extended debugging mode
+(see the description of the
+.B extdebug
+option to the
+.B shopt
+builtin below)
+.TP
+.B BASH_CMDS
+An associative array variable whose members correspond to the internal
+hash table of commands as maintained by the \fBhash\fP builtin.
+Elements added to this array appear in the hash table; unsetting array
+elements cause commands to be removed from the hash table.
+.TP
+.B BASH_COMMAND
+The command currently being executed or about to be executed, unless the
+shell is executing a command as the result of a trap,
+in which case it is the command executing at the time of the trap.
+.TP
+.B BASH_EXECUTION_STRING
+The command argument to the \fB\-c\fP invocation option.
+.TP
+.B BASH_LINENO
+An array variable whose members are the line numbers in source files
+where each corresponding member of
+.SM
+.B FUNCNAME
+was invoked.
+\fB${BASH_LINENO[\fP\fI$i\fP\fB]}\fP is the line number in the source
+file (\fB${BASH_SOURCE[\fP\fI$i+1\fP\fB]}\fP) where
+\fB${FUNCNAME[\fP\fI$i\fP\fB]}\fP was called
+(or \fB${BASH_LINENO[\fP\fI$i-1\fP\fB]}\fP if referenced within another
+shell function).
+Use
+.SM
+.B LINENO
+to obtain the current line number.
+.TP
+.B BASH_REMATCH
+An array variable whose members are assigned by the \fB=~\fP binary
+operator to the \fB[[\fP conditional command.
+The element with index 0 is the portion of the string
+matching the entire regular expression.
+The element with index \fIn\fP is the portion of the
+string matching the \fIn\fPth parenthesized subexpression.
+This variable is read-only.
+.TP
+.B BASH_SOURCE
+An array variable whose members are the source filenames
+where the corresponding shell function names in the
+.SM
+.B FUNCNAME
+array variable are defined.
+The shell function
+\fB${FUNCNAME[\fP\fI$i\fP\fB]}\fP is defined in the file
+\fB${BASH_SOURCE[\fP\fI$i\fP\fB]}\fP and called from
+\fB${BASH_SOURCE[\fP\fI$i+1\fP\fB]}\fP.
+.TP
+.B BASH_SUBSHELL
+Incremented by one within each subshell or subshell environment when
+the shell begins executing in that environment.
+The initial value is 0.
+.TP
+.B BASH_VERSINFO
+A readonly array variable whose members hold version information for
+this instance of
+.BR bash .
+The values assigned to the array members are as follows:
+.sp .5
+.RS
+.TP 24
+.B BASH_VERSINFO[\fR0\fP]
+The major version number (the \fIrelease\fP).
+.TP
+.B BASH_VERSINFO[\fR1\fP]
+The minor version number (the \fIversion\fP).
+.TP
+.B BASH_VERSINFO[\fR2\fP]
+The patch level.
+.TP
+.B BASH_VERSINFO[\fR3\fP]
+The build version.
+.TP
+.B BASH_VERSINFO[\fR4\fP]
+The release status (e.g., \fIbeta1\fP).
+.TP
+.B BASH_VERSINFO[\fR5\fP]
+The value of
+.SM
+.BR MACHTYPE .
+.RE
+.TP
+.B BASH_VERSION
+Expands to a string describing the version of this instance of
+.BR bash .
+.TP
+.B COMP_CWORD
+An index into \fB${COMP_WORDS}\fP of the word containing the current
+cursor position.
+This variable is available only in shell functions invoked by the
+programmable completion facilities (see \fBProgrammable Completion\fP
+below).
+.TP
+.B COMP_KEY
+The key (or final key of a key sequence) used to invoke the current
+completion function.
+.TP
+.B COMP_LINE
+The current command line.
+This variable is available only in shell functions and external
+commands invoked by the
+programmable completion facilities (see \fBProgrammable Completion\fP
+below).
+.TP
+.B COMP_POINT
+The index of the current cursor position relative to the beginning of
+the current command.
+If the current cursor position is at the end of the current command,
+the value of this variable is equal to \fB${#COMP_LINE}\fP.
+This variable is available only in shell functions and external
+commands invoked by the
+programmable completion facilities (see \fBProgrammable Completion\fP
+below).
+.TP
+.B COMP_TYPE
+Set to an integer value corresponding to the type of completion attempted
+that caused a completion function to be called:
+\fITAB\fP, for normal completion,
+\fI?\fP, for listing completions after successive tabs,
+\fI!\fP, for listing alternatives on partial word completion,
+\fI@\fP, to list completions if the word is not unmodified,
+or
+\fI%\fP, for menu completion.
+This variable is available only in shell functions and external
+commands invoked by the
+programmable completion facilities (see \fBProgrammable Completion\fP
+below).
+.TP
+.B COMP_WORDBREAKS
+The set of characters that the \fBreadline\fP library treats as word
+separators when performing word completion.
+If
+.SM
+.B COMP_WORDBREAKS
+is unset, it loses its special properties, even if it is
+subsequently reset.
+.TP
+.B COMP_WORDS
+An array variable (see \fBArrays\fP below) consisting of the individual
+words in the current command line.
+The line is split into words as \fBreadline\fP would split it, using
+.SM
+.B COMP_WORDBREAKS
+as described above.
+This variable is available only in shell functions invoked by the
+programmable completion facilities (see \fBProgrammable Completion\fP
+below).
+.TP
+.B COPROC
+An array variable (see \fBArrays\fP below) created to hold the file descriptors
+for output from and input to an unnamed coprocess (see \fBCoprocesses\fP
+above).
+.TP
+.B DIRSTACK
+An array variable (see
+.B Arrays
+below) containing the current contents of the directory stack.
+Directories appear in the stack in the order they are displayed by the
+.B dirs
+builtin.
+Assigning to members of this array variable may be used to modify
+directories already in the stack, but the
+.B pushd
+and
+.B popd
+builtins must be used to add and remove directories.
+Assignment to this variable will not change the current directory.
+If
+.SM
+.B DIRSTACK
+is unset, it loses its special properties, even if it is
+subsequently reset.
+.TP
+.B EUID
+Expands to the effective user ID of the current user, initialized at
+shell startup. This variable is readonly.
+.TP
+.B FUNCNAME
+An array variable containing the names of all shell functions
+currently in the execution call stack.
+The element with index 0 is the name of any currently-executing
+shell function.
+The bottom-most element (the one with the highest index) is
+.if t \f(CW"main"\fP.
+.if n "main".
+This variable exists only when a shell function is executing.
+Assignments to
+.SM
+.B FUNCNAME
+have no effect and return an error status.
+If
+.SM
+.B FUNCNAME
+is unset, it loses its special properties, even if it is
+subsequently reset.
+.if t .sp 0.5
+.if n .sp 1
+This variable can be used with \fBBASH_LINENO\fP and \fBBASH_SOURCE\fP.
+Each element of \fBFUNCNAME\fP has corresponding elements in
+\fBBASH_LINENO\fP and \fBBASH_SOURCE\fP to describe the call stack.
+For instance, \fB${FUNCNAME[\fP\fI$i\fP\fB]}\fP was called from the file
+\fB${BASH_SOURCE[\fP\fI$i+1\fP\fB]}\fP at line number
+\fB${BASH_LINENO[\fP\fI$i\fP\fB]}\fP.
+The \fBcaller\fP builtin displays the current call stack using this
+information.
+.TP
+.B GROUPS
+An array variable containing the list of groups of which the current
+user is a member.
+Assignments to
+.SM
+.B GROUPS
+have no effect and return an error status.
+If
+.SM
+.B GROUPS
+is unset, it loses its special properties, even if it is
+subsequently reset.
+.TP
+.B HISTCMD
+The history number, or index in the history list, of the current
+command.
+If
+.SM
+.B HISTCMD
+is unset, it loses its special properties, even if it is
+subsequently reset.
+.TP
+.B HOSTNAME
+Automatically set to the name of the current host.
+.TP
+.B HOSTTYPE
+Automatically set to a string that uniquely
+describes the type of machine on which
+.B bash
+is executing.
+The default is system-dependent.
+.TP
+.B LINENO
+Each time this parameter is referenced, the shell substitutes
+a decimal number representing the current sequential line number
+(starting with 1) within a script or function. When not in a
+script or function, the value substituted is not guaranteed to
+be meaningful.
+If
+.SM
+.B LINENO
+is unset, it loses its special properties, even if it is
+subsequently reset.
+.TP
+.B MACHTYPE
+Automatically set to a string that fully describes the system
+type on which
+.B bash
+is executing, in the standard GNU \fIcpu-company-system\fP format.
+The default is system-dependent.
+.TP
+.B MAPFILE
+An array variable (see \fBArrays\fP below) created to hold the text
+read by the \fBmapfile\fP builtin when no variable name is supplied.
+.TP
+.B OLDPWD
+The previous working directory as set by the
+.B cd
+command.
+.TP
+.B OPTARG
+The value of the last option argument processed by the
+.B getopts
+builtin command (see
+.SM
+.B SHELL BUILTIN COMMANDS
+below).
+.TP
+.B OPTIND
+The index of the next argument to be processed by the
+.B getopts
+builtin command (see
+.SM
+.B SHELL BUILTIN COMMANDS
+below).
+.TP
+.B OSTYPE
+Automatically set to a string that
+describes the operating system on which
+.B bash
+is executing.
+The default is system-dependent.
+.TP
+.B PIPESTATUS
+An array variable (see
+.B Arrays
+below) containing a list of exit status values from the processes
+in the most-recently-executed foreground pipeline (which may
+contain only a single command).
+.TP
+.B PPID
+The process ID of the shell's parent. This variable is readonly.
+.TP
+.B PWD
+The current working directory as set by the
+.B cd
+command.
+.TP
+.B RANDOM
+Each time this parameter is referenced, a random integer between
+0 and 32767 is
+generated. The sequence of random numbers may be initialized by assigning
+a value to
+.SM
+.BR RANDOM .
+If
+.SM
+.B RANDOM
+is unset, it loses its special properties, even if it is
+subsequently reset.
+.TP
+.B READLINE_LINE
+The contents of the
+.B readline
+line buffer, for use with
+.if t \f(CWbind -x\fP
+.if n "bind -x"
+(see
+.SM
+.B "SHELL BUILTIN COMMANDS"
+below).
+.TP
+.B READLINE_POINT
+The position of the insertion point in the
+.B readline
+line buffer, for use with
+.if t \f(CWbind -x\fP
+.if n "bind -x"
+(see
+.SM
+.B "SHELL BUILTIN COMMANDS"
+below).
+.TP
+.B REPLY
+Set to the line of input read by the
+.B read
+builtin command when no arguments are supplied.
+.TP
+.B SECONDS
+Each time this parameter is
+referenced, the number of seconds since shell invocation is returned. If a
+value is assigned to
+.SM
+.BR SECONDS ,
+the value returned upon subsequent
+references is
+the number of seconds since the assignment plus the value assigned.
+If
+.SM
+.B SECONDS
+is unset, it loses its special properties, even if it is
+subsequently reset.
+.TP
+.B SHELLOPTS
+A colon-separated list of enabled shell options. Each word in
+the list is a valid argument for the
+.B \-o
+option to the
+.B set
+builtin command (see
+.SM
+.B "SHELL BUILTIN COMMANDS"
+below). The options appearing in
+.SM
+.B SHELLOPTS
+are those reported as
+.I on
+by \fBset \-o\fP.
+If this variable is in the environment when
+.B bash
+starts up, each shell option in the list will be enabled before
+reading any startup files.
+This variable is read-only.
+.TP
+.B SHLVL
+Incremented by one each time an instance of
+.B bash
+is started.
+.TP
+.B UID
+Expands to the user ID of the current user, initialized at shell startup.
+This variable is readonly.
+.PD
+.PP
+The following variables are used by the shell. In some cases,
+.B bash
+assigns a default value to a variable; these cases are noted
+below.
+.PP
+.PD 0
+.TP
+.B BASH_COMPAT
+The value is used to set the shell's compatibility level.
+See the description of the \fBshopt\fP builtin below under
+\fBSHELL BUILTIN COMMANDS\fP
+for a description of the various compatibility
+levels and their effects.
+The value may be a decimal number (e.g., 4.2) or an integer (e.g., 42)
+corresponding to the desired compatibility level.
+If \fBBASH_COMPAT\fP is unset or set to the empty string, the compatibility
+level is set to the default for the current version.
+If \fBBASH_COMPAT\fP is set to a value that is not one of the valid
+compatibility levels, the shell prints an error message and sets the
+compatibility level to the default for the current version.
+The valid compatibility levels correspond to the compatibility options
+accepted by the \fBshopt\fP builtin described below (for example,
+\fBcompat42\fP means that 4.2 and 42 are valid values).
+The current version is also a valid value.
+.TP
+.B BASH_ENV
+If this parameter is set when \fBbash\fP is executing a shell script,
+its value is interpreted as a filename containing commands to
+initialize the shell, as in
+.IR ~/.bashrc .
+The value of
+.SM
+.B BASH_ENV
+is subjected to parameter expansion, command substitution, and arithmetic
+expansion before being interpreted as a filename.
+.SM
+.B PATH
+is not used to search for the resultant filename.
+.TP
+.B BASH_XTRACEFD
+If set to an integer corresponding to a valid file descriptor, \fBbash\fP
+will write the trace output generated when
+.if t \f(CWset -x\fP
+.if n \fIset -x\fP
+is enabled to that file descriptor.
+The file descriptor is closed when
+.SM
+.B BASH_XTRACEFD
+is unset or assigned a new value.
+Unsetting
+.SM
+.B BASH_XTRACEFD
+or assigning it the empty string causes the
+trace output to be sent to the standard error.
+Note that setting
+.SM
+.B BASH_XTRACEFD
+to 2 (the standard error file
+descriptor) and then unsetting it will result in the standard error
+being closed.
+.TP
+.B CDPATH
+The search path for the
+.B cd
+command.
+This is a colon-separated list of directories in which the shell looks
+for destination directories specified by the
+.B cd
+command.
+A sample value is
+.if t \f(CW".:~:/usr"\fP.
+.if n ".:~:/usr".
+.TP
+.B CHILD_MAX
+Set the number of exited child status values for the shell to remember.
+Bash will not allow this value to be decreased below a POSIX-mandated
+minimum, and there is a maximum value (currently 8192) that this may
+not exceed.
+The minimum value is system-dependent.
+.TP
+.B COLUMNS
+Used by the \fBselect\fP compound command to determine the terminal width
+when printing selection lists.
+Automatically set if the
+.B checkwinsize
+option is enabled or in an interactive shell upon receipt of a
+.SM
+.BR SIGWINCH .
+.TP
+.B COMPREPLY
+An array variable from which \fBbash\fP reads the possible completions
+generated by a shell function invoked by the programmable completion
+facility (see \fBProgrammable Completion\fP below).
+Each array element contains one possible completion.
+.TP
+.B EMACS
+If \fBbash\fP finds this variable in the environment when the shell starts
+with value
+.if t \f(CWt\fP,
+.if n "t",
+it assumes that the shell is running in an Emacs shell buffer and disables
+line editing.
+.TP
+.B ENV
+Similar to
+.SM
+.BR BASH_ENV ;
+used when the shell is invoked in POSIX mode.
+.TP
+.B FCEDIT
+The default editor for the
+.B fc
+builtin command.
+.TP
+.B FIGNORE
+A colon-separated list of suffixes to ignore when performing
+filename completion (see
+.SM
+.B READLINE
+below).
+A filename whose suffix matches one of the entries in
+.SM
+.B FIGNORE
+is excluded from the list of matched filenames.
+A sample value is
+.if t \f(CW".o:~"\fP.
+.if n ".o:~".
+.TP
+.B FUNCNEST
+If set to a numeric value greater than 0, defines a maximum function
+nesting level. Function invocations that exceed this nesting level
+will cause the current command to abort.
+.TP
+.B GLOBIGNORE
+A colon-separated list of patterns defining the set of filenames to
+be ignored by pathname expansion.
+If a filename matched by a pathname expansion pattern also matches one
+of the patterns in
+.SM
+.BR GLOBIGNORE ,
+it is removed from the list of matches.
+.TP
+.B HISTCONTROL
+A colon-separated list of values controlling how commands are saved on
+the history list.
+If the list of values includes
+.IR ignorespace ,
+lines which begin with a
+.B space
+character are not saved in the history list.
+A value of
+.I ignoredups
+causes lines matching the previous history entry to not be saved.
+A value of
+.I ignoreboth
+is shorthand for \fIignorespace\fP and \fIignoredups\fP.
+A value of
+.IR erasedups
+causes all previous lines matching the current line to be removed from
+the history list before that line is saved.
+Any value not in the above list is ignored.
+If
+.SM
+.B HISTCONTROL
+is unset, or does not include a valid value,
+all lines read by the shell parser are saved on the history list,
+subject to the value of
+.SM
+.BR HISTIGNORE .
+The second and subsequent lines of a multi-line compound command are
+not tested, and are added to the history regardless of the value of
+.SM
+.BR HISTCONTROL .
+.TP
+.B HISTFILE
+The name of the file in which command history is saved (see
+.SM
+.B HISTORY
+below). The default value is \fI~/.bash_history\fP. If unset, the
+command history is not saved when a shell exits.
+.TP
+.B HISTFILESIZE
+The maximum number of lines contained in the history file. When this
+variable is assigned a value, the history file is truncated, if
+necessary,
+to contain no more than that number of lines by removing the oldest entries.
+The history file is also truncated to this size after
+writing it when a shell exits.
+If the value is 0, the history file is truncated to zero size.
+Non-numeric values and numeric values less than zero inhibit truncation.
+The shell sets the default value to the value of \fBHISTSIZE\fP
+after reading any startup files.
+.TP
+.B HISTIGNORE
+A colon-separated list of patterns used to decide which command lines
+should be saved on the history list. Each pattern is anchored at the
+beginning of the line and must match the complete line (no implicit
+`\fB*\fP' is appended). Each pattern is tested against the line
+after the checks specified by
+.SM
+.B HISTCONTROL
+are applied.
+In addition to the normal shell pattern matching characters, `\fB&\fP'
+matches the previous history line. `\fB&\fP' may be escaped using a
+backslash; the backslash is removed before attempting a match.
+The second and subsequent lines of a multi-line compound command are
+not tested, and are added to the history regardless of the value of
+.SM
+.BR HISTIGNORE .
+.TP
+.B HISTSIZE
+The number of commands to remember in the command history (see
+.SM
+.B HISTORY
+below).
+If the value is 0, commands are not saved in the history list.
+Numeric values less than zero result in every command being saved
+on the history list (there is no limit).
+The shell sets the default value to 500 after reading any startup files.
+.TP
+.B HISTTIMEFORMAT
+If this variable is set and not null, its value is used as a format string
+for \fIstrftime\fP(3) to print the time stamp associated with each history
+entry displayed by the \fBhistory\fP builtin.
+If this variable is set, time stamps are written to the history file so
+they may be preserved across shell sessions.
+This uses the history comment character to distinguish timestamps from
+other history lines.
+.TP
+.B HOME
+The home directory of the current user; the default argument for the
+\fBcd\fP builtin command.
+The value of this variable is also used when performing tilde expansion.
+.TP
+.B HOSTFILE
+Contains the name of a file in the same format as
+.FN /etc/hosts
+that should be read when the shell needs to complete a
+hostname.
+The list of possible hostname completions may be changed while the
+shell is running;
+the next time hostname completion is attempted after the
+value is changed,
+.B bash
+adds the contents of the new file to the existing list.
+If
+.SM
+.B HOSTFILE
+is set, but has no value, or does not name a readable file,
+\fBbash\fP attempts to read
+.FN /etc/hosts
+to obtain the list of possible hostname completions.
+When
+.SM
+.B HOSTFILE
+is unset, the hostname list is cleared.
+.TP
+.B IFS
+The
+.I Internal Field Separator
+that is used
+for word splitting after expansion and to
+split lines into words with the
+.B read
+builtin command. The default value is
+``<space><tab><newline>''.
+.TP
+.B IGNOREEOF
+Controls the
+action of an interactive shell on receipt of an
+.SM
+.B EOF
+character as the sole input. If set, the value is the number of
+consecutive
+.SM
+.B EOF
+characters which must be
+typed as the first characters on an input line before
+.B bash
+exits. If the variable exists but does not have a numeric value, or
+has no value, the default value is 10. If it does not exist,
+.SM
+.B EOF
+signifies the end of input to the shell.
+.TP
+.B INPUTRC
+The filename for the
+.B readline
+startup file, overriding the default of
+.FN ~/.inputrc
+(see
+.SM
+.B READLINE
+below).
+.TP
+.B LANG
+Used to determine the locale category for any category not specifically
+selected with a variable starting with \fBLC_\fP.
+.TP
+.B LC_ALL
+This variable overrides the value of
+.SM
+.B LANG
+and any other
+\fBLC_\fP variable specifying a locale category.
+.TP
+.B LC_COLLATE
+This variable determines the collation order used when sorting the
+results of pathname expansion, and determines the behavior of range
+expressions, equivalence classes, and collating sequences within
+pathname expansion and pattern matching.
+.TP
+.B LC_CTYPE
+This variable determines the interpretation of characters and the
+behavior of character classes within pathname expansion and pattern
+matching.
+.TP
+.B LC_MESSAGES
+This variable determines the locale used to translate double-quoted
+strings preceded by a \fB$\fP.
+.TP
+.B LC_NUMERIC
+This variable determines the locale category used for number formatting.
+.TP
+.B LINES
+Used by the \fBselect\fP compound command to determine the column length
+for printing selection lists.
+Automatically set if the
+.B checkwinsize
+option is enabled or in an interactive shell upon receipt of a
+.SM
+.BR SIGWINCH .
+.TP
+.B MAIL
+If this parameter is set to a file or directory name and the
+.SM
+.B MAILPATH
+variable is not set,
+.B bash
+informs the user of the arrival of mail in the specified file or
+Maildir-format directory.
+.TP
+.B MAILCHECK
+Specifies how
+often (in seconds)
+.B bash
+checks for mail. The default is 60 seconds. When it is time to check
+for mail, the shell does so before displaying the primary prompt.
+If this variable is unset, or set to a value that is not a number
+greater than or equal to zero, the shell disables mail checking.
+.TP
+.B MAILPATH
+A colon-separated list of filenames to be checked for mail.
+The message to be printed when mail arrives in a particular file
+may be specified by separating the filename from the message with a `?'.
+When used in the text of the message, \fB$_\fP expands to the name of
+the current mailfile.
+Example:
+.RS
+.PP
+\fBMAILPATH\fP=\(aq/var/mail/bfox?"You have mail":~/shell\-mail?"$_ has mail!"\(aq
+.PP
+.B Bash
+supplies a default value for this variable, but the location of the user
+mail files that it uses is system dependent (e.g., /var/mail/\fB$USER\fP).
+.RE
+.TP
+.B OPTERR
+If set to the value 1,
+.B bash
+displays error messages generated by the
+.B getopts
+builtin command (see
+.SM
+.B SHELL BUILTIN COMMANDS
+below).
+.SM
+.B OPTERR
+is initialized to 1 each time the shell is invoked or a shell
+script is executed.
+.TP
+.B PATH
+The search path for commands. It
+is a colon-separated list of directories in which
+the shell looks for commands (see
+.SM
+.B COMMAND EXECUTION
+below).
+A zero-length (null) directory name in the value of
+.SM
+.B PATH
+indicates the current directory.
+A null directory name may appear as two adjacent colons, or as an initial
+or trailing colon.
+The default path is system-dependent,
+and is set by the administrator who installs
+.BR bash .
+A common value is
+.if t \f(CW/usr/local/bin:/usr/local/sbin:/usr/bin:/usr/sbin:/bin:/sbin\fP.
+.if n ``/usr/local/bin:/usr/local/sbin:/usr/bin:/usr/sbin:/bin:/sbin''.
+.TP
+.B POSIXLY_CORRECT
+If this variable is in the environment when \fBbash\fP starts, the shell
+enters \fIposix mode\fP before reading the startup files, as if the
+.B \-\-posix
+invocation option had been supplied. If it is set while the shell is
+running, \fBbash\fP enables \fIposix mode\fP, as if the command
+.if t \f(CWset -o posix\fP
+.if n \fIset -o posix\fP
+had been executed.
+.TP
+.B PROMPT_COMMAND
+If set, the value is executed as a command prior to issuing each primary
+prompt.
+.TP
+.B PROMPT_DIRTRIM
+If set to a number greater than zero, the value is used as the number of
+trailing directory components to retain when expanding the \fB\ew\fP and
+\fB\eW\fP prompt string escapes (see
+.SM
+.B PROMPTING
+below). Characters removed are replaced with an ellipsis.
+.TP
+.B PS1
+The value of this parameter is expanded (see
+.SM
+.B PROMPTING
+below) and used as the primary prompt string. The default value is
+``\fB\es\-\ev\e$ \fP''.
+.TP
+.B PS2
+The value of this parameter is expanded as with
+.SM
+.B PS1
+and used as the secondary prompt string. The default is
+``\fB> \fP''.
+.TP
+.B PS3
+The value of this parameter is used as the prompt for the
+.B select
+command (see
+.SM
+.B SHELL GRAMMAR
+above).
+.TP
+.B PS4
+The value of this parameter is expanded as with
+.SM
+.B PS1
+and the value is printed before each command
+.B bash
+displays during an execution trace. The first character of
+.SM
+.B PS4
+is replicated multiple times, as necessary, to indicate multiple
+levels of indirection. The default is ``\fB+ \fP''.
+.TP
+.B SHELL
+The full pathname to the shell is kept in this environment variable.
+If it is not set when the shell starts,
+.B bash
+assigns to it the full pathname of the current user's login shell.
+.TP
+.B TIMEFORMAT
+The value of this parameter is used as a format string specifying
+how the timing information for pipelines prefixed with the
+.B time
+reserved word should be displayed.
+The \fB%\fP character introduces an escape sequence that is
+expanded to a time value or other information.
+The escape sequences and their meanings are as follows; the
+braces denote optional portions.
+.sp .5
+.RS
+.PD 0
+.TP 10
+.B %%
+A literal \fB%\fP.
+.TP
+.B %[\fIp\fP][l]R
+The elapsed time in seconds.
+.TP
+.B %[\fIp\fP][l]U
+The number of CPU seconds spent in user mode.
+.TP
+.B %[\fIp\fP][l]S
+The number of CPU seconds spent in system mode.
+.TP
+.B %P
+The CPU percentage, computed as (%U + %S) / %R.
+.PD
+.RE
+.IP
+The optional \fIp\fP is a digit specifying the \fIprecision\fP,
+the number of fractional digits after a decimal point.
+A value of 0 causes no decimal point or fraction to be output.
+At most three places after the decimal point may be specified;
+values of \fIp\fP greater than 3 are changed to 3.
+If \fIp\fP is not specified, the value 3 is used.
+.IP
+The optional \fBl\fP specifies a longer format, including
+minutes, of the form \fIMM\fPm\fISS\fP.\fIFF\fPs.
+The value of \fIp\fP determines whether or not the fraction is
+included.
+.IP
+If this variable is not set, \fBbash\fP acts as if it had the
+value \fB$\(aq\enreal\et%3lR\enuser\et%3lU\ensys\et%3lS\(aq\fP.
+If the value is null, no timing information is displayed.
+A trailing newline is added when the format string is displayed.
+.PD 0
+.TP
+.B TMOUT
+If set to a value greater than zero,
+.SM
+.B TMOUT
+is treated as the
+default timeout for the \fBread\fP builtin.
+The \fBselect\fP command terminates if input does not arrive
+after
+.SM
+.B TMOUT
+seconds when input is coming from a terminal.
+In an interactive shell, the value is interpreted as the
+number of seconds to wait for a line of input after issuing the
+primary prompt.
+.B Bash
+terminates after waiting for that number of seconds if a complete
+line of input does not arrive.
+.TP
+.B TMPDIR
+If set, \fBbash\fP uses its value as the name of a directory in which
+\fBbash\fP creates temporary files for the shell's use.
+.TP
+.B auto_resume
+This variable controls how the shell interacts with the user and
+job control. If this variable is set, single word simple
+commands without redirections are treated as candidates for resumption
+of an existing stopped job. There is no ambiguity allowed; if there is
+more than one job beginning with the string typed, the job most recently
+accessed is selected. The
+.I name
+of a stopped job, in this context, is the command line used to
+start it.
+If set to the value
+.IR exact ,
+the string supplied must match the name of a stopped job exactly;
+if set to
+.IR substring ,
+the string supplied needs to match a substring of the name of a
+stopped job. The
+.I substring
+value provides functionality analogous to the
+.B %?
+job identifier (see
+.SM
+.B JOB CONTROL
+below). If set to any other value, the supplied string must
+be a prefix of a stopped job's name; this provides functionality
+analogous to the \fB%\fP\fIstring\fP job identifier.
+.TP
+.B histchars
+The two or three characters which control history expansion
+and tokenization (see
+.SM
+.B HISTORY EXPANSION
+below). The first character is the \fIhistory expansion\fP character,
+the character which signals the start of a history
+expansion, normally `\fB!\fP'.
+The second character is the \fIquick substitution\fP
+character, which is used as shorthand for re-running the previous
+command entered, substituting one string for another in the command.
+The default is `\fB^\fP'.
+The optional third character is the character
+which indicates that the remainder of the line is a comment when found
+as the first character of a word, normally `\fB#\fP'. The history
+comment character causes history substitution to be skipped for the
+remaining words on the line. It does not necessarily cause the shell
+parser to treat the rest of the line as a comment.
+.PD
+.SS Arrays
+.B Bash
+provides one-dimensional indexed and associative array variables.
+Any variable may be used as an indexed array; the
+.B declare
+builtin will explicitly declare an array.
+There is no maximum
+limit on the size of an array, nor any requirement that members
+be indexed or assigned contiguously.
+Indexed arrays are referenced using integers (including arithmetic
+expressions) and are zero-based; associative arrays are referenced
+using arbitrary strings.
+Unless otherwise noted, indexed array indices must be non-negative integers.
+.PP
+An indexed array is created automatically if any variable is assigned to
+using the syntax \fIname\fP[\fIsubscript\fP]=\fIvalue\fP. The
+.I subscript
+is treated as an arithmetic expression that must evaluate to a number.
+To explicitly declare an indexed array, use
+.B declare \-a \fIname\fP
+(see
+.SM
+.B SHELL BUILTIN COMMANDS
+below).
+.B declare \-a \fIname\fP[\fIsubscript\fP]
+is also accepted; the \fIsubscript\fP is ignored.
+.PP
+Associative arrays are created using
+.BR "declare \-A \fIname\fP" .
+.PP
+Attributes may be
+specified for an array variable using the
+.B declare
+and
+.B readonly
+builtins. Each attribute applies to all members of an array.
+.PP
+Arrays are assigned to using compound assignments of the form
+\fIname\fP=\fB(\fPvalue\fI1\fP ... value\fIn\fP\fB)\fP, where each
+\fIvalue\fP is of the form [\fIsubscript\fP]=\fIstring\fP.
+Indexed array assignments do not require anything but \fIstring\fP.
+When assigning to indexed arrays, if the optional brackets and subscript
+are supplied, that index is assigned to;
+otherwise the index of the element assigned is the last index assigned
+to by the statement plus one. Indexing starts at zero.
+.PP
+When assigning to an associative array, the subscript is required.
+.PP
+This syntax is also accepted by the
+.B declare
+builtin. Individual array elements may be assigned to using the
+\fIname\fP[\fIsubscript\fP]=\fIvalue\fP syntax introduced above.
+When assigning to an indexed array, if
+.I name
+is subscripted by a negative number, that number is
+interpreted as relative to one greater than the maximum index of
+\fIname\fP, so negative indices count back from the end of the
+array, and an index of \-1 references the last element.
+.PP
+Any element of an array may be referenced using
+${\fIname\fP[\fIsubscript\fP]}. The braces are required to avoid
+conflicts with pathname expansion. If
+\fIsubscript\fP is \fB@\fP or \fB*\fP, the word expands to
+all members of \fIname\fP. These subscripts differ only when the
+word appears within double quotes. If the word is double-quoted,
+${\fIname\fP[*]} expands to a single
+word with the value of each array member separated by the first
+character of the
+.SM
+.B IFS
+special variable, and ${\fIname\fP[@]} expands each element of
+\fIname\fP to a separate word. When there are no array members,
+${\fIname\fP[@]} expands to nothing.
+If the double-quoted expansion occurs within a word, the expansion of
+the first parameter is joined with the beginning part of the original
+word, and the expansion of the last parameter is joined with the last
+part of the original word.
+This is analogous to the expansion
+of the special parameters \fB*\fP and \fB@\fP (see
+.B Special Parameters
+above). ${#\fIname\fP[\fIsubscript\fP]} expands to the length of
+${\fIname\fP[\fIsubscript\fP]}. If \fIsubscript\fP is \fB*\fP or
+\fB@\fP, the expansion is the number of elements in the array.
+If the
+.I subscript
+used to reference an element of an indexed array
+evaluates to a number less than zero, it is
+interpreted as relative to one greater than the maximum index of the array,
+so negative indices count back from the end of the
+array, and an index of \-1 references the last element.
+.PP
+Referencing an array variable without a subscript is equivalent to
+referencing the array with a subscript of 0.
+Any reference to a variable using a valid subscript is legal, and
+.B bash
+will create an array if necessary.
+.PP
+An array variable is considered set if a subscript has been assigned a
+value. The null string is a valid value.
+.PP
+It is possible to obtain the keys (indices) of an array as well as the values.
+${\fB!\fP\fIname\fP[\fI@\fP]} and ${\fB!\fP\fIname\fP[\fI*\fP]}
+expand to the indices assigned in array variable \fIname\fP.
+The treatment when in double quotes is similar to the expansion of the
+special parameters \fI@\fP and \fI*\fP within double quotes.
+.PP
+The
+.B unset
+builtin is used to destroy arrays. \fBunset\fP \fIname\fP[\fIsubscript\fP]
+destroys the array element at index \fIsubscript\fP.
+Negative subscripts to indexed arrays are interpreted as described above.
+Care must be taken to avoid unwanted side effects caused by pathname
+expansion.
+\fBunset\fP \fIname\fP, where \fIname\fP is an array, or
+\fBunset\fP \fIname\fP[\fIsubscript\fP], where
+\fIsubscript\fP is \fB*\fP or \fB@\fP, removes the entire array.
+.PP
+The
+.BR declare ,
+.BR local ,
+and
+.B readonly
+builtins each accept a
+.B \-a
+option to specify an indexed array and a
+.B \-A
+option to specify an associative array.
+If both options are supplied,
+.B \-A
+takes precedence.
+The
+.B read
+builtin accepts a
+.B \-a
+option to assign a list of words read from the standard input
+to an array. The
+.B set
+and
+.B declare
+builtins display array values in a way that allows them to be
+reused as assignments.
+.SH EXPANSION
+Expansion is performed on the command line after it has been split into
+words. There are seven kinds of expansion performed:
+.IR "brace expansion" ,
+.IR "tilde expansion" ,
+.IR "parameter and variable expansion" ,
+.IR "command substitution" ,
+.IR "arithmetic expansion" ,
+.IR "word splitting" ,
+and
+.IR "pathname expansion" .
+.PP
+The order of expansions is:
+brace expansion;
+tilde expansion, parameter and variable expansion, arithmetic expansion,
+and command substitution (done in a left-to-right fashion);
+word splitting;
+and pathname expansion.
+.PP
+On systems that can support it, there is an additional expansion
+available: \fIprocess substitution\fP.
+This is performed at the
+same time as tilde, parameter, variable, and arithmetic expansion and
+command substitution.
+.PP
+Only brace expansion, word splitting, and pathname expansion
+can change the number of words of the expansion; other expansions
+expand a single word to a single word.
+The only exceptions to this are the expansions of
+"\fB$@\fP" and "\fB${\fP\fIname\fP\fB[@]}\fP"
+as explained above (see
+.SM
+.BR PARAMETERS ).
+.SS Brace Expansion
+.PP
+.I "Brace expansion"
+is a mechanism by which arbitrary strings
+may be generated. This mechanism is similar to
+\fIpathname expansion\fP, but the filenames generated
+need not exist. Patterns to be brace expanded take
+the form of an optional
+.IR preamble ,
+followed by either a series of comma-separated strings or
+a sequence expression between a pair of braces, followed by
+an optional
+.IR postscript .
+The preamble is prefixed to each string contained
+within the braces, and the postscript is then appended
+to each resulting string, expanding left to right.
+.PP
+Brace expansions may be nested. The results of each expanded
+string are not sorted; left to right order is preserved.
+For example, a\fB{\fPd,c,b\fB}\fPe expands into `ade ace abe'.
+.PP
+A sequence expression takes the form
+\fB{\fP\fIx\fP\fB..\fP\fIy\fP\fB[..\fP\fIincr\fP\fB]}\fP,
+where \fIx\fP and \fIy\fP are either integers or single characters,
+and \fIincr\fP, an optional increment, is an integer.
+When integers are supplied, the expression expands to each number between
+\fIx\fP and \fIy\fP, inclusive.
+Supplied integers may be prefixed with \fI0\fP to force each term to have the
+same width.
+When either \fIx\fP or \fPy\fP begins with a zero, the shell
+attempts to force all generated terms to contain the same number of digits,
+zero-padding where necessary.
+When characters are supplied, the expression expands to each character
+lexicographically between \fIx\fP and \fIy\fP, inclusive,
+using the default C locale.
+Note that both \fIx\fP and \fIy\fP must be of the same type.
+When the increment is supplied, it is used as the difference between
+each term. The default increment is 1 or -1 as appropriate.
+.PP
+Brace expansion is performed before any other expansions,
+and any characters special to other expansions are preserved
+in the result. It is strictly textual.
+.B Bash
+does not apply any syntactic interpretation to the context of the
+expansion or the text between the braces.
+.PP
+A correctly-formed brace expansion must contain unquoted opening
+and closing braces, and at least one unquoted comma or a valid
+sequence expression.
+Any incorrectly formed brace expansion is left unchanged.
+A \fB{\fP or \fB,\fP may be quoted with a backslash to prevent its
+being considered part of a brace expression.
+To avoid conflicts with parameter expansion, the string \fB${\fP
+is not considered eligible for brace expansion.
+.PP
+This construct is typically used as shorthand when the common
+prefix of the strings to be generated is longer than in the
+above example:
+.RS
+.PP
+mkdir /usr/local/src/bash/{old,new,dist,bugs}
+.RE
+or
+.RS
+chown root /usr/{ucb/{ex,edit},lib/{ex?.?*,how_ex}}
+.RE
+.PP
+Brace expansion introduces a slight incompatibility with
+historical versions of
+.BR sh .
+.B sh
+does not treat opening or closing braces specially when they
+appear as part of a word, and preserves them in the output.
+.B Bash
+removes braces from words as a consequence of brace
+expansion. For example, a word entered to
+.B sh
+as \fIfile{1,2}\fP
+appears identically in the output. The same word is
+output as
+.I file1 file2
+after expansion by
+.BR bash .
+If strict compatibility with
+.B sh
+is desired, start
+.B bash
+with the
+.B +B
+option or disable brace expansion with the
+.B +B
+option to the
+.B set
+command (see
+.SM
+.B SHELL BUILTIN COMMANDS
+below).
+.SS Tilde Expansion
+.PP
+If a word begins with an unquoted tilde character (`\fB~\fP'), all of
+the characters preceding the first unquoted slash (or all characters,
+if there is no unquoted slash) are considered a \fItilde-prefix\fP.
+If none of the characters in the tilde-prefix are quoted, the
+characters in the tilde-prefix following the tilde are treated as a
+possible \fIlogin name\fP.
+If this login name is the null string, the tilde is replaced with the
+value of the shell parameter
+.SM
+.BR HOME .
+If
+.SM
+.B HOME
+is unset, the home directory of the user executing the shell is
+substituted instead.
+Otherwise, the tilde-prefix is replaced with the home directory
+associated with the specified login name.
+.PP
+If the tilde-prefix is a `~+', the value of the shell variable
+.SM
+.B PWD
+replaces the tilde-prefix.
+If the tilde-prefix is a `~\-', the value of the shell variable
+.SM
+.BR OLDPWD ,
+if it is set, is substituted.
+If the characters following the tilde in the tilde-prefix consist
+of a number \fIN\fP, optionally prefixed
+by a `+' or a `\-', the tilde-prefix is replaced with the corresponding
+element from the directory stack, as it would be displayed by the
+.B dirs
+builtin invoked with the tilde-prefix as an argument.
+If the characters following the tilde in the tilde-prefix consist of a
+number without a leading `+' or `\-', `+' is assumed.
+.PP
+If the login name is invalid, or the tilde expansion fails, the word
+is unchanged.
+.PP
+Each variable assignment is checked for unquoted tilde-prefixes immediately
+following a
+.B :
+or the first
+.BR = .
+In these cases, tilde expansion is also performed.
+Consequently, one may use filenames with tildes in assignments to
+.SM
+.BR PATH ,
+.SM
+.BR MAILPATH ,
+and
+.SM
+.BR CDPATH ,
+and the shell assigns the expanded value.
+.SS Parameter Expansion
+.PP
+The `\fB$\fP' character introduces parameter expansion,
+command substitution, or arithmetic expansion. The parameter name
+or symbol to be expanded may be enclosed in braces, which
+are optional but serve to protect the variable to be expanded from
+characters immediately following it which could be
+interpreted as part of the name.
+.PP
+When braces are used, the matching ending brace is the first `\fB}\fP'
+not escaped by a backslash or within a quoted string, and not within an
+embedded arithmetic expansion, command substitution, or parameter
+expansion.
+.PP
+.PD 0
+.TP
+${\fIparameter\fP}
+The value of \fIparameter\fP is substituted. The braces are required
+when
+.I parameter
+is a positional parameter with more than one digit,
+or when
+.I parameter
+is followed by a character which is not to be
+interpreted as part of its name.
+The \fIparameter\fP is a shell parameter as described above
+\fBPARAMETERS\fP) or an array reference (\fBArrays\fP).
+.PD
+.PP
+If the first character of \fIparameter\fP is an exclamation point (\fB!\fP),
+it introduces a level of variable indirection.
+\fBBash\fP uses the value of the variable formed from the rest of
+\fIparameter\fP as the name of the variable; this variable is then
+expanded and that value is used in the rest of the substitution, rather
+than the value of \fIparameter\fP itself.
+This is known as \fIindirect expansion\fP.
+The exceptions to this are the expansions of ${\fB!\fP\fIprefix\fP\fB*\fP} and
+${\fB!\fP\fIname\fP[\fI@\fP]} described below.
+The exclamation point must immediately follow the left brace in order to
+introduce indirection.
+.PP
+In each of the cases below, \fIword\fP is subject to tilde expansion,
+parameter expansion, command substitution, and arithmetic expansion.
+.PP
+When not performing substring expansion, using the forms documented below
+(e.g., \fB:-\fP),
+\fBbash\fP tests for a parameter that is unset or null. Omitting the colon
+results in a test only for a parameter that is unset.
+.PP
+.PD 0
+.TP
+${\fIparameter\fP\fB:\-\fP\fIword\fP}
+\fBUse Default Values\fP. If
+.I parameter
+is unset or null, the expansion of
+.I word
+is substituted. Otherwise, the value of
+.I parameter
+is substituted.
+.TP
+${\fIparameter\fP\fB:=\fP\fIword\fP}
+\fBAssign Default Values\fP.
+If
+.I parameter
+is unset or null, the expansion of
+.I word
+is assigned to
+.IR parameter .
+The value of
+.I parameter
+is then substituted. Positional parameters and special parameters may
+not be assigned to in this way.
+.TP
+${\fIparameter\fP\fB:?\fP\fIword\fP}
+\fBDisplay Error if Null or Unset\fP.
+If
+.I parameter
+is null or unset, the expansion of \fIword\fP (or a message to that effect
+if
+.I word
+is not present) is written to the standard error and the shell, if it
+is not interactive, exits. Otherwise, the value of \fIparameter\fP is
+substituted.
+.TP
+${\fIparameter\fP\fB:+\fP\fIword\fP}
+\fBUse Alternate Value\fP.
+If
+.I parameter
+is null or unset, nothing is substituted, otherwise the expansion of
+.I word
+is substituted.
+.TP
+${\fIparameter\fP\fB:\fP\fIoffset\fP}
+.PD 0
+.TP
+${\fIparameter\fP\fB:\fP\fIoffset\fP\fB:\fP\fIlength\fP}
+.PD
+\fBSubstring Expansion\fP.
+Expands to up to \fIlength\fP characters of the value of \fIparameter\fP
+starting at the character specified by \fIoffset\fP.
+If \fIparameter\fP is \fB@\fP, an indexed array subscripted by
+\fB@\fP or \fB*\fP, or an associative array name, the results differ as
+described below.
+If \fIlength\fP is omitted, expands to the substring of the value of
+\fIparameter\fP starting at the character specified by \fIoffset\fP
+and extending to the end of the value.
+\fIlength\fP and \fIoffset\fP are arithmetic expressions (see
+.SM
+.B
+ARITHMETIC EVALUATION
+below).
+.sp 1
+If \fIoffset\fP evaluates to a number less than zero, the value
+is used as an offset in characters
+from the end of the value of \fIparameter\fP.
+If \fIlength\fP evaluates to a number less than zero,
+it is interpreted as an offset in characters
+from the end of the value of \fIparameter\fP rather than
+a number of characters, and the expansion is the characters between
+\fIoffset\fP and that result.
+Note that a negative offset must be separated from the colon by at least
+one space to avoid being confused with the \fB:-\fP expansion.
+.sp 1
+If \fIparameter\fP is \fB@\fP, the result is \fIlength\fP positional
+parameters beginning at \fIoffset\fP.
+A negative \fIoffset\fP is taken relative to one greater than the greatest
+positional parameter, so an offset of -1 evaluates to the last positional
+parameter.
+It is an expansion error if \fIlength\fP evaluates to a number less than
+zero.
+.sp 1
+If \fIparameter\fP is an indexed array name subscripted by @ or *,
+the result is the \fIlength\fP
+members of the array beginning with ${\fIparameter\fP[\fIoffset\fP]}.
+A negative \fIoffset\fP is taken relative to one greater than the maximum
+index of the specified array.
+It is an expansion error if \fIlength\fP evaluates to a number less than
+zero.
+.sp 1
+Substring expansion applied to an associative array produces undefined
+results.
+.sp 1
+Substring indexing is zero-based unless the positional parameters
+are used, in which case the indexing starts at 1 by default.
+If \fIoffset\fP is 0, and the positional parameters are used, \fB$0\fP is
+prefixed to the list.
+.TP
+${\fB!\fP\fIprefix\fP\fB*\fP}
+.PD 0
+.TP
+${\fB!\fP\fIprefix\fP\fB@\fP}
+.PD
+\fBNames matching prefix\fP.
+Expands to the names of variables whose names begin with \fIprefix\fP,
+separated by the first character of the
+.SM
+.B IFS
+special variable.
+When \fI@\fP is used and the expansion appears within double quotes, each
+variable name expands to a separate word.
+.TP
+${\fB!\fP\fIname\fP[\fI@\fP]}
+.PD 0
+.TP
+${\fB!\fP\fIname\fP[\fI*\fP]}
+.PD
+\fBList of array keys\fP.
+If \fIname\fP is an array variable, expands to the list of array indices
+(keys) assigned in \fIname\fP.
+If \fIname\fP is not an array, expands to 0 if \fIname\fP is set and null
+otherwise.
+When \fI@\fP is used and the expansion appears within double quotes, each
+key expands to a separate word.
+.TP
+${\fB#\fP\fIparameter\fP}
+\fBParameter length\fP.
+The length in characters of the value of \fIparameter\fP is substituted.
+If
+.I parameter
+is
+.B *
+or
+.BR @ ,
+the value substituted is the number of positional parameters.
+If
+.I parameter
+is an array name subscripted by
+.B *
+or
+.BR @ ,
+the value substituted is the number of elements in the array.
+If
+.I parameter
+is an indexed array name subscripted by a negative number, that number is
+interpreted as relative to one greater than the maximum index of
+\fIparameter\fP, so negative indices count back from the end of the
+array, and an index of \-1 references the last element.
+.TP
+${\fIparameter\fP\fB#\fP\fIword\fP}
+.PD 0
+.TP
+${\fIparameter\fP\fB##\fP\fIword\fP}
+.PD
+\fBRemove matching prefix pattern\fP.
+The
+.I word
+is expanded to produce a pattern just as in pathname
+expansion. If the pattern matches the beginning of
+the value of
+.IR parameter ,
+then the result of the expansion is the expanded value of
+.I parameter
+with the shortest matching pattern (the ``\fB#\fP'' case) or the
+longest matching pattern (the ``\fB##\fP'' case) deleted.
+If
+.I parameter
+is
+.B @
+or
+.BR * ,
+the pattern removal operation is applied to each positional
+parameter in turn, and the expansion is the resultant list.
+If
+.I parameter
+is an array variable subscripted with
+.B @
+or
+.BR * ,
+the pattern removal operation is applied to each member of the
+array in turn, and the expansion is the resultant list.
+.TP
+${\fIparameter\fP\fB%\fP\fIword\fP}
+.PD 0
+.TP
+${\fIparameter\fP\fB%%\fP\fIword\fP}
+.PD
+\fBRemove matching suffix pattern\fP.
+The \fIword\fP is expanded to produce a pattern just as in
+pathname expansion.
+If the pattern matches a trailing portion of the expanded value of
+.IR parameter ,
+then the result of the expansion is the expanded value of
+.I parameter
+with the shortest matching pattern (the ``\fB%\fP'' case) or the
+longest matching pattern (the ``\fB%%\fP'' case) deleted.
+If
+.I parameter
+is
+.B @
+or
+.BR * ,
+the pattern removal operation is applied to each positional
+parameter in turn, and the expansion is the resultant list.
+If
+.I parameter
+is an array variable subscripted with
+.B @
+or
+.BR * ,
+the pattern removal operation is applied to each member of the
+array in turn, and the expansion is the resultant list.
+.TP
+${\fIparameter\fP\fB/\fP\fIpattern\fP\fB/\fP\fIstring\fP}
+\fBPattern substitution\fP.
+The \fIpattern\fP is expanded to produce a pattern just as in
+pathname expansion.
+\fIParameter\fP is expanded and the longest match of \fIpattern\fP
+against its value is replaced with \fIstring\fP.
+If \fIpattern\fP begins with \fB/\fP, all matches of \fIpattern\fP are
+replaced with \fIstring\fP. Normally only the first match is replaced.
+If \fIpattern\fP begins with \fB#\fP, it must match at the beginning
+of the expanded value of \fIparameter\fP.
+If \fIpattern\fP begins with \fB%\fP, it must match at the end
+of the expanded value of \fIparameter\fP.
+If \fIstring\fP is null, matches of \fIpattern\fP are deleted
+and the \fB/\fP following \fIpattern\fP may be omitted.
+If the
+.B nocasematch
+shell option is enabled, the match is performed without regard to the case
+of alphabetic characters.
+If
+.I parameter
+is
+.B @
+or
+.BR * ,
+the substitution operation is applied to each positional
+parameter in turn, and the expansion is the resultant list.
+If
+.I parameter
+is an array variable subscripted with
+.B @
+or
+.BR * ,
+the substitution operation is applied to each member of the
+array in turn, and the expansion is the resultant list.
+.TP
+${\fIparameter\fP\fB^\fP\fIpattern\fP}
+.PD 0
+.TP
+${\fIparameter\fP\fB^^\fP\fIpattern\fP}
+.TP
+${\fIparameter\fP\fB,\fP\fIpattern\fP}
+.TP
+${\fIparameter\fP\fB,,\fP\fIpattern\fP}
+.PD
+\fBCase modification\fP.
+This expansion modifies the case of alphabetic characters in \fIparameter\fP.
+The \fIpattern\fP is expanded to produce a pattern just as in
+pathname expansion.
+Each character in the expanded value of \fIparameter\fP is tested against
+\fIpattern\fP, and, if it matches the pattern, its case is converted.
+The pattern should not attempt to match more than one character.
+The \fB^\fP operator converts lowercase letters matching \fIpattern\fP
+to uppercase; the \fB,\fP operator converts matching uppercase letters
+to lowercase.
+The \fB^^\fP and \fB,,\fP expansions convert each matched character in the
+expanded value; the \fB^\fP and \fB,\fP expansions match and convert only
+the first character in the expanded value.
+If \fIpattern\fP is omitted, it is treated like a \fB?\fP, which matches
+every character.
+If
+.I parameter
+is
+.B @
+or
+.BR * ,
+the case modification operation is applied to each positional
+parameter in turn, and the expansion is the resultant list.
+If
+.I parameter
+is an array variable subscripted with
+.B @
+or
+.BR * ,
+the case modification operation is applied to each member of the
+array in turn, and the expansion is the resultant list.
+.TP
+${\fIparameter\fP\fB@\fP\fIoperator\fP}
+\fBParameter transformation\fP.
+The expansion is either a transformation of the value of \fIparameter\fP
+or information about \fIparameter\fP itself, depending on the value of
+\fIoperator\fP. Each \fIoperator\fP is a single letter:
+.sp 1
+.RS
+.PD 0
+.TP
+.B Q
+The expansion is a string that is the value of \fIparameter\fP quoted in a
+format that can be reused as input.
+.TP
+.B E
+The expansion is a string that is the value of \fIparameter\fP with backslash
+escape sequences expanded as with the \fB$'...'\fP quoting mechansim.
+.TP
+.B P
+The expansion is a string that is the result of expanding the value of
+\fIparameter\fP as if it were a prompt string (see \fBPROMPTING\fP below).
+.TP
+.B A
+The expansion is a string in the form of a \fBdeclare\fP command that, if
+evaluated, will recreate \fIparameter\fP with its attributes and value.
+.TP
+.B a
+The expansion is a string consisting of flag values representing
+\fIparameter\fP's attributes.
+.PD
+.PP
+If
+.I parameter
+is
+.B @
+or
+.BR * ,
+the operation is applied to each positional
+parameter in turn, and the expansion is the resultant list.
+If
+.I parameter
+is an array variable subscripted with
+.B @
+or
+.BR * ,
+the case modification operation is applied to each member of the
+array in turn, and the expansion is the resultant list.
+.sp 1
+The result of the expansion is subject to word splitting and pathname
+expansion as described below.
+.RE
+.SS Command Substitution
+.PP
+\fICommand substitution\fP allows the output of a command to replace
+the command name. There are two forms:
+.RS
+.PP
+\fB$(\fP\fIcommand\fP\|\fB)\fP
+.RE
+or
+.RS
+\fB\`\fP\fIcommand\fP\fB\`\fP
+.RE
+.PP
+.B Bash
+performs the expansion by executing \fIcommand\fP and
+replacing the command substitution with the standard output of the
+command, with any trailing newlines deleted.
+Embedded newlines are not deleted, but they may be removed during
+word splitting.
+The command substitution \fB$(cat \fIfile\fP)\fR can be replaced by
+the equivalent but faster \fB$(< \fIfile\fP)\fR.
+.PP
+When the old-style backquote form of substitution is used,
+backslash retains its literal meaning except when followed by
+.BR $ ,
+.BR \` ,
+or
+.BR \e .
+The first backquote not preceded by a backslash terminates the
+command substitution.
+When using the $(\^\fIcommand\fP\|) form, all characters between the
+parentheses make up the command; none are treated specially.
+.PP
+Command substitutions may be nested. To nest when using the backquoted form,
+escape the inner backquotes with backslashes.
+.PP
+If the substitution appears within double quotes, word splitting and
+pathname expansion are not performed on the results.
+.SS Arithmetic Expansion
+.PP
+Arithmetic expansion allows the evaluation of an arithmetic expression
+and the substitution of the result. The format for arithmetic expansion is:
+.RS
+.PP
+\fB$((\fP\fIexpression\fP\fB))\fP
+.RE
+.PP
+The
+.I expression
+is treated as if it were within double quotes, but a double quote
+inside the parentheses is not treated specially.
+All tokens in the expression undergo parameter and variable expansion,
+command substitution, and quote removal.
+The result is treated as the arithmetic expression to be evaluated.
+Arithmetic expansions may be nested.
+.PP
+The evaluation is performed according to the rules listed below under
+.SM
+.BR "ARITHMETIC EVALUATION" .
+If
+.I expression
+is invalid,
+.B bash
+prints a message indicating failure and no substitution occurs.
+.SS Process Substitution
+.PP
+\fIProcess substitution\fP is supported on systems that support named
+pipes (\fIFIFOs\fP) or the \fB/dev/fd\fP method of naming open files.
+It takes the form of
+\fB<(\fP\fIlist\^\fP\fB)\fP
+or
+\fB>(\fP\fIlist\^\fP\fB)\fP.
+The process \fIlist\fP is run with its input or output connected to a
+\fIFIFO\fP or some file in \fB/dev/fd\fP. The name of this file is
+passed as an argument to the current command as the result of the
+expansion. If the \fB>(\fP\fIlist\^\fP\fB)\fP form is used, writing to
+the file will provide input for \fIlist\fP. If the
+\fB<(\fP\fIlist\^\fP\fB)\fP form is used, the file passed as an
+argument should be read to obtain the output of \fIlist\fP.
+.PP
+When available, process substitution is performed
+simultaneously with parameter and variable expansion,
+command substitution,
+and arithmetic expansion.
+.SS Word Splitting
+.PP
+The shell scans the results of
+parameter expansion,
+command substitution,
+and
+arithmetic expansion
+that did not occur within double quotes for
+.IR "word splitting" .
+.PP
+The shell treats each character of
+.SM
+.B IFS
+as a delimiter, and splits the results of the other
+expansions into words using these characters as field terminators.
+If
+.SM
+.B IFS
+is unset, or its
+value is exactly
+.BR <space><tab><newline> ,
+the default, then
+sequences of
+.BR <space> ,
+.BR <tab> ,
+and
+.B <newline>
+at the beginning and end of the results of the previous
+expansions are ignored, and
+any sequence of
+.SM
+.B IFS
+characters not at the beginning or end serves to delimit words.
+If
+.SM
+.B IFS
+has a value other than the default, then sequences of
+the whitespace characters
+.B space
+and
+.B tab
+are ignored at the beginning and end of the
+word, as long as the whitespace character is in the
+value of
+.SM
+.BR IFS
+(an
+.SM
+.B IFS
+whitespace character).
+Any character in
+.SM
+.B IFS
+that is not
+.SM
+.B IFS
+whitespace, along with any adjacent
+.SM
+.B IFS
+whitespace characters, delimits a field.
+A sequence of
+.SM
+.B IFS
+whitespace characters is also treated as a delimiter.
+If the value of
+.SM
+.B IFS
+is null, no word splitting occurs.
+.PP
+Explicit null arguments (\^\f3"\^"\fP or \^\f3\(aq\^\(aq\fP\^) are retained.
+Unquoted implicit null arguments, resulting from the expansion of
+parameters that have no values, are removed.
+If a parameter with no value is expanded within double quotes, a
+null argument results and is retained.
+.PP
+Note that if no expansion occurs, no splitting
+is performed.
+.SS Pathname Expansion
+.PP
+After word splitting,
+unless the
+.B \-f
+option has been set,
+.B bash
+scans each word for the characters
+.BR * ,
+.BR ? ,
+and
+.BR [ .
+If one of these characters appears, then the word is
+regarded as a
+.IR pattern ,
+and replaced with an alphabetically sorted list of
+filenames matching the pattern
+(see
+.SM
+.B "Pattern Matching"
+below).
+If no matching filenames are found,
+and the shell option
+.B nullglob
+is not enabled, the word is left unchanged.
+If the
+.B nullglob
+option is set, and no matches are found,
+the word is removed.
+If the
+.B failglob
+shell option is set, and no matches are found, an error message
+is printed and the command is not executed.
+If the shell option
+.B nocaseglob
+is enabled, the match is performed without regard to the case
+of alphabetic characters.
+When a pattern is used for pathname expansion,
+the character
+.B ``.''
+at the start of a name or immediately following a slash
+must be matched explicitly, unless the shell option
+.B dotglob
+is set.
+When matching a pathname, the slash character must always be
+matched explicitly.
+In other cases, the
+.B ``.''
+character is not treated specially.
+See the description of
+.B shopt
+below under
+.SM
+.B SHELL BUILTIN COMMANDS
+for a description of the
+.BR nocaseglob ,
+.BR nullglob ,
+.BR failglob ,
+and
+.B dotglob
+shell options.
+.PP
+The
+.SM
+.B GLOBIGNORE
+shell variable may be used to restrict the set of filenames matching a
+.IR pattern .
+If
+.SM
+.B GLOBIGNORE
+is set, each matching filename that also matches one of the patterns in
+.SM
+.B GLOBIGNORE
+is removed from the list of matches.
+If the \fBnocaseglob\fP option is set, the matching against the patterns in
+.SM
+.B GLOBIGNORE
+is performed without regard to case.
+The filenames
+.B ``.''
+and
+.B ``..''
+are always ignored when
+.SM
+.B GLOBIGNORE
+is set and not null. However, setting
+.SM
+.B GLOBIGNORE
+to a non-null value has the effect of enabling the
+.B dotglob
+shell option, so all other filenames beginning with a
+.B ``.''
+will match.
+To get the old behavior of ignoring filenames beginning with a
+.BR ``.'' ,
+make
+.B ``.*''
+one of the patterns in
+.SM
+.BR GLOBIGNORE .
+The
+.B dotglob
+option is disabled when
+.SM
+.B GLOBIGNORE
+is unset.
+.PP
+\fBPattern Matching\fP
+.PP
+Any character that appears in a pattern, other than the special pattern
+characters described below, matches itself. The NUL character may not
+occur in a pattern. A backslash escapes the following character; the
+escaping backslash is discarded when matching.
+The special pattern characters must be quoted if
+they are to be matched literally.
+.PP
+The special pattern characters have the following meanings:
+.PP
+.PD 0
+.RS
+.TP
+.B *
+Matches any string, including the null string.
+When the \fBglobstar\fP shell option is enabled, and \fB*\fP is used in
+a pathname expansion context, two adjacent \fB*\fPs used as a single
+pattern will match all files and zero or more directories and
+subdirectories.
+If followed by a \fB/\fP, two adjacent \fB*\fPs will match only directories
+and subdirectories.
+.TP
+.B ?
+Matches any single character.
+.TP
+.B [...]
+Matches any one of the enclosed characters. A pair of characters
+separated by a hyphen denotes a
+\fIrange expression\fP;
+any character that falls between those two characters, inclusive,
+using the current locale's collating sequence and character set,
+is matched. If the first character following the
+.B [
+is a
+.B !
+or a
+.B ^
+then any character not enclosed is matched.
+The sorting order of characters in range expressions is determined by
+the current locale and the values of the
+.SM
+.B LC_COLLATE
+or
+.SM
+.B LC_ALL
+shell variables, if set.
+To obtain the traditional interpretation of range expressions, where
+.B [a\-d]
+is equivalent to
+.BR [abcd] ,
+set value of the
+.B LC_ALL
+shell variable to
+.BR C ,
+or enable the
+.B globasciiranges
+shell option.
+A
+.B \-
+may be matched by including it as the first or last character
+in the set.
+A
+.B ]
+may be matched by including it as the first character
+in the set.
+.br
+.if t .sp 0.5
+.if n .sp 1
+Within
+.B [
+and
+.BR ] ,
+\fIcharacter classes\fP can be specified using the syntax
+\fB[:\fP\fIclass\fP\fB:]\fP, where \fIclass\fP is one of the
+following classes defined in the POSIX standard:
+.PP
+.RS
+.B
+.if n alnum alpha ascii blank cntrl digit graph lower print punct space upper word xdigit
+.if t alnum alpha ascii blank cntrl digit graph lower print punct space upper word xdigit
+.br
+A character class matches any character belonging to that class.
+The \fBword\fP character class matches letters, digits, and the character _.
+.br
+.if t .sp 0.5
+.if n .sp 1
+Within
+.B [
+and
+.BR ] ,
+an \fIequivalence class\fP can be specified using the syntax
+\fB[=\fP\fIc\fP\fB=]\fP, which matches all characters with the
+same collation weight (as defined by the current locale) as
+the character \fIc\fP.
+.br
+.if t .sp 0.5
+.if n .sp 1
+Within
+.B [
+and
+.BR ] ,
+the syntax \fB[.\fP\fIsymbol\fP\fB.]\fP matches the collating symbol
+\fIsymbol\fP.
+.RE
+.RE
+.PD
+.PP
+If the \fBextglob\fP shell option is enabled using the \fBshopt\fP
+builtin, several extended pattern matching operators are recognized.
+In the following description, a \fIpattern-list\fP is a list of one
+or more patterns separated by a \fB|\fP.
+Composite patterns may be formed using one or more of the following
+sub-patterns:
+.sp 1
+.PD 0
+.RS
+.TP
+\fB?(\fP\^\fIpattern-list\^\fP\fB)\fP
+Matches zero or one occurrence of the given patterns
+.TP
+\fB*(\fP\^\fIpattern-list\^\fP\fB)\fP
+Matches zero or more occurrences of the given patterns
+.TP
+\fB+(\fP\^\fIpattern-list\^\fP\fB)\fP
+Matches one or more occurrences of the given patterns
+.TP
+\fB@(\fP\^\fIpattern-list\^\fP\fB)\fP
+Matches one of the given patterns
+.TP
+\fB!(\fP\^\fIpattern-list\^\fP\fB)\fP
+Matches anything except one of the given patterns
+.RE
+.PD
+.SS Quote Removal
+.PP
+After the preceding expansions, all unquoted occurrences of the
+characters
+.BR \e ,
+.BR \(aq ,
+and \^\f3"\fP\^ that did not result from one of the above
+expansions are removed.
+.SH REDIRECTION
+Before a command is executed, its input and output
+may be
+.I redirected
+using a special notation interpreted by the shell.
+Redirection allows commands' file handles to be
+duplicated, opened, closed,
+made to refer to different files,
+and can change the files the command reads from and writes to.
+Redirection may also be used to modify file handles in the
+current shell execution environment.
+The following redirection
+operators may precede or appear anywhere within a
+.I simple command
+or may follow a
+.IR command .
+Redirections are processed in the order they appear, from
+left to right.
+.PP
+Each redirection that may be preceded by a file descriptor number
+may instead be preceded by a word of the form {\fIvarname\fP}.
+In this case, for each redirection operator except
+>&- and <&-, the shell will allocate a file descriptor greater
+than or equal to 10 and assign it to \fIvarname\fP.
+If >&- or <&- is preceded
+by {\fIvarname\fP}, the value of \fIvarname\fP defines the file
+descriptor to close.
+.PP
+In the following descriptions, if the file descriptor number is
+omitted, and the first character of the redirection operator is
+.BR < ,
+the redirection refers to the standard input (file descriptor
+0). If the first character of the redirection operator is
+.BR > ,
+the redirection refers to the standard output (file descriptor
+1).
+.PP
+The word following the redirection operator in the following
+descriptions, unless otherwise noted, is subjected to
+brace expansion, tilde expansion, parameter and variable expansion,
+command substitution, arithmetic expansion, quote removal,
+pathname expansion, and word splitting.
+If it expands to more than one word,
+.B bash
+reports an error.
+.PP
+Note that the order of redirections is significant. For example,
+the command
+.RS
+.PP
+ls \fB>\fP dirlist 2\fB>&\fP1
+.RE
+.PP
+directs both standard output and standard error to the file
+.IR dirlist ,
+while the command
+.RS
+.PP
+ls 2\fB>&\fP1 \fB>\fP dirlist
+.RE
+.PP
+directs only the standard output to file
+.IR dirlist ,
+because the standard error was duplicated from the standard output
+before the standard output was redirected to
+.IR dirlist .
+.PP
+\fBBash\fP handles several filenames specially when they are used in
+redirections, as described in the following table:
+.RS
+.PP
+.PD 0
+.TP
+.B /dev/fd/\fIfd\fP
+If \fIfd\fP is a valid integer, file descriptor \fIfd\fP is duplicated.
+.TP
+.B /dev/stdin
+File descriptor 0 is duplicated.
+.TP
+.B /dev/stdout
+File descriptor 1 is duplicated.
+.TP
+.B /dev/stderr
+File descriptor 2 is duplicated.
+.TP
+.B /dev/tcp/\fIhost\fP/\fIport\fP
+If \fIhost\fP is a valid hostname or Internet address, and \fIport\fP
+is an integer port number or service name, \fBbash\fP attempts to open
+the corresponding TCP socket.
+.TP
+.B /dev/udp/\fIhost\fP/\fIport\fP
+If \fIhost\fP is a valid hostname or Internet address, and \fIport\fP
+is an integer port number or service name, \fBbash\fP attempts to open
+the corresponding UDP socket.
+.PD
+.RE
+.PP
+A failure to open or create a file causes the redirection to fail.
+.PP
+Redirections using file descriptors greater than 9 should be used with
+care, as they may conflict with file descriptors the shell uses
+internally.
+.SS Redirecting Input
+.PP
+Redirection of input causes the file whose name results from
+the expansion of
+.I word
+to be opened for reading on file descriptor
+.IR n ,
+or the standard input (file descriptor 0) if
+.I n
+is not specified.
+.PP
+The general format for redirecting input is:
+.RS
+.PP
+[\fIn\fP]\fB<\fP\fIword\fP
+.RE
+.SS Redirecting Output
+.PP
+Redirection of output causes the file whose name results from
+the expansion of
+.I word
+to be opened for writing on file descriptor
+.IR n ,
+or the standard output (file descriptor 1) if
+.I n
+is not specified. If the file does not exist it is created;
+if it does exist it is truncated to zero size.
+.PP
+The general format for redirecting output is:
+.RS
+.PP
+[\fIn\fP]\fB>\fP\fIword\fP
+.RE
+.PP
+If the redirection operator is
+.BR > ,
+and the
+.B noclobber
+option to the
+.B set
+builtin has been enabled, the redirection will fail if the file
+whose name results from the expansion of \fIword\fP exists and is
+a regular file.
+If the redirection operator is
+.BR >| ,
+or the redirection operator is
+.B >
+and the
+.B noclobber
+option to the
+.B set
+builtin command is not enabled, the redirection is attempted even
+if the file named by \fIword\fP exists.
+.SS Appending Redirected Output
+.PP
+Redirection of output in this fashion
+causes the file whose name results from
+the expansion of
+.I word
+to be opened for appending on file descriptor
+.IR n ,
+or the standard output (file descriptor 1) if
+.I n
+is not specified. If the file does not exist it is created.
+.PP
+The general format for appending output is:
+.RS
+.PP
+[\fIn\fP]\fB>>\fP\fIword\fP
+.RE
+.PP
+.SS Redirecting Standard Output and Standard Error
+.PP
+This construct allows both the
+standard output (file descriptor 1) and
+the standard error output (file descriptor 2)
+to be redirected to the file whose name is the
+expansion of
+.IR word .
+.PP
+There are two formats for redirecting standard output and
+standard error:
+.RS
+.PP
+\fB&>\fP\fIword\fP
+.RE
+and
+.RS
+\fB>&\fP\fIword\fP
+.RE
+.PP
+Of the two forms, the first is preferred.
+This is semantically equivalent to
+.RS
+.PP
+\fB>\fP\fIword\fP 2\fB>&\fP1
+.RE
+.PP
+When using the second form, \fIword\fP may not expand to a number or
+\fB\-\fP. If it does, other redirection operators apply
+(see \fBDuplicating File Descriptors\fP below) for compatibility
+reasons.
+.SS Appending Standard Output and Standard Error
+.PP
+This construct allows both the
+standard output (file descriptor 1) and
+the standard error output (file descriptor 2)
+to be appended to the file whose name is the
+expansion of
+.IR word .
+.PP
+The format for appending standard output and standard error is:
+.RS
+.PP
+\fB&>>\fP\fIword\fP
+.RE
+.PP
+This is semantically equivalent to
+.RS
+.PP
+\fB>>\fP\fIword\fP 2\fB>&\fP1
+.RE
+.PP
+(see \fBDuplicating File Descriptors\fP below).
+.SS Here Documents
+.PP
+This type of redirection instructs the shell to read input from the
+current source until a line containing only
+.I delimiter
+(with no trailing blanks)
+is seen. All of
+the lines read up to that point are then used as the standard
+input (or file descriptor \fIn\fP if \fIn\fP is specified) for a command.
+.PP
+The format of here-documents is:
+.RS
+.PP
+.nf
+[\fIn\fP]\fB<<\fP[\fB\-\fP]\fIword\fP
+ \fIhere-document\fP
+\fIdelimiter\fP
+.fi
+.RE
+.PP
+No parameter and variable expansion, command substitution,
+arithmetic expansion, or pathname expansion is performed on
+.IR word .
+If any characters in
+.I word
+are quoted, the
+.I delimiter
+is the result of quote removal on
+.IR word ,
+and the lines in the here-document are not expanded.
+If \fIword\fP is unquoted,
+all lines of the here-document are subjected to
+parameter expansion, command substitution, and arithmetic expansion,
+the character sequence
+.B \e<newline>
+is ignored, and
+.B \e
+must be used to quote the characters
+.BR \e ,
+.BR $ ,
+and
+.BR \` .
+.PP
+If the redirection operator is
+.BR <<\- ,
+then all leading tab characters are stripped from input lines and the
+line containing
+.IR delimiter .
+This allows
+here-documents within shell scripts to be indented in a
+natural fashion.
+.SS "Here Strings"
+A variant of here documents, the format is:
+.RS
+.PP
+.nf
+[\fIn\fP]\fB<<<\fP\fIword\fP
+.fi
+.RE
+.PP
+The \fIword\fP undergoes
+brace expansion, tilde expansion, parameter and variable expansion,
+command substitution, arithmetic expansion, and quote removal.
+Pathname expansion and word splitting are not performed.
+The result is supplied as a single string to the command on its
+standard input (or file descriptor \fIn\fP if \fIn\fP is specified).
+.SS "Duplicating File Descriptors"
+
+.PP
+The redirection operator
+.RS
+.PP
+[\fIn\fP]\fB<&\fP\fIword\fP
+.RE
+.PP
+is used to duplicate input file descriptors.
+If
+.I word
+expands to one or more digits, the file descriptor denoted by
+.I n
+is made to be a copy of that file descriptor.
+If the digits in
+.I word
+do not specify a file descriptor open for input, a redirection error occurs.
+If
+.I word
+evaluates to
+.BR \- ,
+file descriptor
+.I n
+is closed. If
+.I n
+is not specified, the standard input (file descriptor 0) is used.
+.PP
+The operator
+.RS
+.PP
+[\fIn\fP]\fB>&\fP\fIword\fP
+.RE
+.PP
+is used similarly to duplicate output file descriptors. If
+.I n
+is not specified, the standard output (file descriptor 1) is used.
+If the digits in
+.I word
+do not specify a file descriptor open for output, a redirection error occurs.
+If
+.I word
+evaluates to
+.BR \- ,
+file descriptor
+.I n
+is closed.
+As a special case, if \fIn\fP is omitted, and \fIword\fP does not
+expand to one or more digits or \fB\-\fP, the standard output and standard
+error are redirected as described previously.
+.SS "Moving File Descriptors"
+.PP
+The redirection operator
+.RS
+.PP
+[\fIn\fP]\fB<&\fP\fIdigit\fP\fB\-\fP
+.RE
+.PP
+moves the file descriptor \fIdigit\fP to file descriptor
+.IR n ,
+or the standard input (file descriptor 0) if \fIn\fP is not specified.
+\fIdigit\fP is closed after being duplicated to \fIn\fP.
+.PP
+Similarly, the redirection operator
+.RS
+.PP
+[\fIn\fP]\fB>&\fP\fIdigit\fP\fB\-\fP
+.RE
+.PP
+moves the file descriptor \fIdigit\fP to file descriptor
+.IR n ,
+or the standard output (file descriptor 1) if \fIn\fP is not specified.
+.SS "Opening File Descriptors for Reading and Writing"
+.PP
+The redirection operator
+.RS
+.PP
+[\fIn\fP]\fB<>\fP\fIword\fP
+.RE
+.PP
+causes the file whose name is the expansion of
+.I word
+to be opened for both reading and writing on file descriptor
+.IR n ,
+or on file descriptor 0 if
+.I n
+is not specified. If the file does not exist, it is created.
+.SH ALIASES
+\fIAliases\fP allow a string to be substituted for a word when it is used
+as the first word of a simple command.
+The shell maintains a list of aliases that may be set and unset with the
+.B alias
+and
+.B unalias
+builtin commands (see
+.SM
+.B SHELL BUILTIN COMMANDS
+below).
+The first word of each simple command, if unquoted,
+is checked to see if it has an
+alias. If so, that word is replaced by the text of the alias.
+The characters \fB/\fP, \fB$\fP, \fB\`\fP, and \fB=\fP and
+any of the shell \fImetacharacters\fP or quoting characters
+listed above may not appear in an alias name.
+The replacement text may contain any valid shell input,
+including shell metacharacters.
+The first word of the replacement text is tested
+for aliases, but a word that is identical to an alias being expanded
+is not expanded a second time.
+This means that one may alias
+.B ls
+to
+.BR "ls \-F" ,
+for instance, and
+.B bash
+does not try to recursively expand the replacement text.
+If the last character of the alias value is a
+.IR blank ,
+then the next command
+word following the alias is also checked for alias expansion.
+.PP
+Aliases are created and listed with the
+.B alias
+command, and removed with the
+.B unalias
+command.
+.PP
+There is no mechanism for using arguments in the replacement text.
+If arguments are needed, a shell function should be used (see
+.SM
+.B FUNCTIONS
+below).
+.PP
+Aliases are not expanded when the shell is not interactive, unless
+the
+.B expand_aliases
+shell option is set using
+.B shopt
+(see the description of
+.B shopt
+under
+.SM
+\fBSHELL BUILTIN COMMANDS\fP
+below).
+.PP
+The rules concerning the definition and use of aliases are
+somewhat confusing.
+.B Bash
+always reads at least one complete line
+of input before executing any
+of the commands on that line. Aliases are expanded when a
+command is read, not when it is executed. Therefore, an
+alias definition appearing on the same line as another
+command does not take effect until the next line of input is read.
+The commands following the alias definition
+on that line are not affected by the new alias.
+This behavior is also an issue when functions are executed.
+Aliases are expanded when a function definition is read,
+not when the function is executed, because a function definition
+is itself a command. As a consequence, aliases
+defined in a function are not available until after that
+function is executed. To be safe, always put
+alias definitions on a separate line, and do not use
+.B alias
+in compound commands.
+.PP
+For almost every purpose, aliases are superseded by
+shell functions.
+.SH FUNCTIONS
+A shell function, defined as described above under
+.SM
+.BR "SHELL GRAMMAR" ,
+stores a series of commands for later execution.
+When the name of a shell function is used as a simple command name,
+the list of commands associated with that function name is executed.
+Functions are executed in the context of the
+current shell; no new process is created to interpret
+them (contrast this with the execution of a shell script).
+When a function is executed, the arguments to the
+function become the positional parameters
+during its execution.
+The special parameter
+.B #
+is updated to reflect the change. Special parameter \fB0\fP
+is unchanged.
+The first element of the
+.SM
+.B FUNCNAME
+variable is set to the name of the function while the function
+is executing.
+.PP
+All other aspects of the shell execution
+environment are identical between a function and its caller
+with these exceptions: the
+.SM
+.B DEBUG
+and
+.B RETURN
+traps (see the description of the
+.B trap
+builtin under
+.SM
+.B SHELL BUILTIN COMMANDS
+below) are not inherited unless the function has been given the
+\fBtrace\fP attribute (see the description of the
+.SM
+.B declare
+builtin below) or the
+\fB\-o functrace\fP shell option has been enabled with
+the \fBset\fP builtin
+(in which case all functions inherit the \fBDEBUG\fP and \fBRETURN\fP traps),
+and the
+.SM
+.B ERR
+trap is not inherited unless the \fB\-o errtrace\fP shell option has
+been enabled.
+.PP
+Variables local to the function may be declared with the
+.B local
+builtin command. Ordinarily, variables and their values
+are shared between the function and its caller.
+.PP
+The \fBFUNCNEST\fP variable, if set to a numeric value greater
+than 0, defines a maximum function nesting level. Function
+invocations that exceed the limit cause the entire command to
+abort.
+.PP
+If the builtin command
+.B return
+is executed in a function, the function completes and
+execution resumes with the next command after the function
+call.
+Any command associated with the \fBRETURN\fP trap is executed
+before execution resumes.
+When a function completes, the values of the
+positional parameters and the special parameter
+.B #
+are restored to the values they had prior to the function's
+execution.
+.PP
+Function names and definitions may be listed with the
+.B \-f
+option to the
+.B declare
+or
+.B typeset
+builtin commands. The
+.B \-F
+option to
+.B declare
+or
+.B typeset
+will list the function names only
+(and optionally the source file and line number, if the \fBextdebug\fP
+shell option is enabled).
+Functions may be exported so that subshells
+automatically have them defined with the
+.B \-f
+option to the
+.B export
+builtin.
+A function definition may be deleted using the \fB\-f\fP option to
+the
+.B unset
+builtin.
+Note that shell functions and variables with the same name may result
+in multiple identically-named entries in the environment passed to the
+shell's children.
+Care should be taken in cases where this may cause a problem.
+.PP
+Functions may be recursive.
+The \fBFUNCNEST\fP variable may be used to limit the depth of the
+function call stack and restrict the number of function invocations.
+By default, no limit is imposed on the number of recursive calls.
+.SH "ARITHMETIC EVALUATION"
+The shell allows arithmetic expressions to be evaluated, under
+certain circumstances (see the \fBlet\fP and \fBdeclare\fP builtin
+commands and \fBArithmetic Expansion\fP).
+Evaluation is done in fixed-width integers with no check for overflow,
+though division by 0 is trapped and flagged as an error.
+The operators and their precedence, associativity, and values
+are the same as in the C language.
+The following list of operators is grouped into levels of
+equal-precedence operators.
+The levels are listed in order of decreasing precedence.
+.PP
+.PD 0
+.TP
+.B \fIid\fP++ \fIid\fP\-\-
+variable post-increment and post-decrement
+.TP
+.B ++\fIid\fP \-\-\fIid\fP
+variable pre-increment and pre-decrement
+.TP
+.B \- +
+unary minus and plus
+.TP
+.B ! ~
+logical and bitwise negation
+.TP
+.B **
+exponentiation
+.TP
+.B * / %
+multiplication, division, remainder
+.TP
+.B + \-
+addition, subtraction
+.TP
+.B << >>
+left and right bitwise shifts
+.TP
+.B <= >= < >
+comparison
+.TP
+.B == !=
+equality and inequality
+.TP
+.B &
+bitwise AND
+.TP
+.B ^
+bitwise exclusive OR
+.TP
+.B |
+bitwise OR
+.TP
+.B &&
+logical AND
+.TP
+.B ||
+logical OR
+.TP
+.B \fIexpr\fP?\fIexpr\fP:\fIexpr\fP
+conditional operator
+.TP
+.B = *= /= %= += \-= <<= >>= &= ^= |=
+assignment
+.TP
+.B \fIexpr1\fP , \fIexpr2\fP
+comma
+.PD
+.PP
+Shell variables are allowed as operands; parameter expansion is
+performed before the expression is evaluated.
+Within an expression, shell variables may also be referenced by name
+without using the parameter expansion syntax.
+A shell variable that is null or unset evaluates to 0 when referenced
+by name without using the parameter expansion syntax.
+The value of a variable is evaluated as an arithmetic expression
+when it is referenced, or when a variable which has been given the
+\fIinteger\fP attribute using \fBdeclare -i\fP is assigned a value.
+A null value evaluates to 0.
+A shell variable need not have its \fIinteger\fP attribute
+turned on to be used in an expression.
+.PP
+Constants with a leading 0 are interpreted as octal numbers.
+A leading 0x or 0X denotes hexadecimal.
+Otherwise, numbers take the form [\fIbase#\fP]n, where the optional \fIbase\fP
+is a decimal number between 2 and 64 representing the arithmetic
+base, and \fIn\fP is a number in that base.
+If \fIbase#\fP is omitted, then base 10 is used.
+When specifying \fIn\fP,
+the digits greater< than 9 are represented by the lowercase letters,
+the uppercase letters, @, and _, in that order.
+If \fIbase\fP is less than or equal to 36, lowercase and uppercase
+letters may be used interchangeably to represent numbers between 10
+and 35.
+.PP
+Operators are evaluated in order of precedence. Sub-expressions in
+parentheses are evaluated first and may override the precedence
+rules above.
+.SH "CONDITIONAL EXPRESSIONS"
+Conditional expressions are used by the \fB[[\fP compound command and
+the \fBtest\fP and \fB[\fP builtin commands to test file attributes
+and perform string and arithmetic comparisons.
+Expressions are formed from the following unary or binary primaries.
+If any \fIfile\fP argument to one of the primaries is of the form
+\fI/dev/fd/n\fP, then file descriptor \fIn\fP is checked.
+If the \fIfile\fP argument to one of the primaries is one of
+\fI/dev/stdin\fP, \fI/dev/stdout\fP, or \fI/dev/stderr\fP, file
+descriptor 0, 1, or 2, respectively, is checked.
+.PP
+Unless otherwise specified, primaries that operate on files follow symbolic
+links and operate on the target of the link, rather than the link itself.
+.if t .sp 0.5
+.if n .sp 1
+When used with \fB[[\fP, the \fB<\fP and \fB>\fP operators sort
+lexicographically using the current locale.
+The \fBtest\fP command sorts using ASCII ordering.
+.sp 1
+.PD 0
+.TP
+.B \-a \fIfile\fP
+True if \fIfile\fP exists.
+.TP
+.B \-b \fIfile\fP
+True if \fIfile\fP exists and is a block special file.
+.TP
+.B \-c \fIfile\fP
+True if \fIfile\fP exists and is a character special file.
+.TP
+.B \-d \fIfile\fP
+True if \fIfile\fP exists and is a directory.
+.TP
+.B \-e \fIfile\fP
+True if \fIfile\fP exists.
+.TP
+.B \-f \fIfile\fP
+True if \fIfile\fP exists and is a regular file.
+.TP
+.B \-g \fIfile\fP
+True if \fIfile\fP exists and is set-group-id.
+.TP
+.B \-h \fIfile\fP
+True if \fIfile\fP exists and is a symbolic link.
+.TP
+.B \-k \fIfile\fP
+True if \fIfile\fP exists and its ``sticky'' bit is set.
+.TP
+.B \-p \fIfile\fP
+True if \fIfile\fP exists and is a named pipe (FIFO).
+.TP
+.B \-r \fIfile\fP
+True if \fIfile\fP exists and is readable.
+.TP
+.B \-s \fIfile\fP
+True if \fIfile\fP exists and has a size greater than zero.
+.TP
+.B \-t \fIfd\fP
+True if file descriptor
+.I fd
+is open and refers to a terminal.
+.TP
+.B \-u \fIfile\fP
+True if \fIfile\fP exists and its set-user-id bit is set.
+.TP
+.B \-w \fIfile\fP
+True if \fIfile\fP exists and is writable.
+.TP
+.B \-x \fIfile\fP
+True if \fIfile\fP exists and is executable.
+.TP
+.B \-G \fIfile\fP
+True if \fIfile\fP exists and is owned by the effective group id.
+.TP
+.B \-L \fIfile\fP
+True if \fIfile\fP exists and is a symbolic link.
+.TP
+.B \-N \fIfile\fP
+True if \fIfile\fP exists and has been modified since it was last read.
+.TP
+.B \-O \fIfile\fP
+True if \fIfile\fP exists and is owned by the effective user id.
+.TP
+.B \-S \fIfile\fP
+True if \fIfile\fP exists and is a socket.
+.TP
+\fIfile1\fP \fB\-ef\fP \fIfile2\fP
+True if \fIfile1\fP and \fIfile2\fP refer to the same device and
+inode numbers.
+.TP
+\fIfile1\fP \-\fBnt\fP \fIfile2\fP
+True if \fIfile1\fP is newer (according to modification date) than \fIfile2\fP,
+or if \fIfile1\fP exists and \fPfile2\fP does not.
+.TP
+\fIfile1\fP \-\fBot\fP \fIfile2\fP
+True if \fIfile1\fP is older than \fIfile2\fP, or if \fIfile2\fP exists
+and \fIfile1\fP does not.
+.TP
+.B \-o \fIoptname\fP
+True if the shell option
+.I optname
+is enabled.
+See the list of options under the description of the
+.B \-o
+option to the
+.B set
+builtin below.
+.TP
+.B \-v \fIvarname\fP
+True if the shell variable
+.I varname
+is set (has been assigned a value).
+.TP
+.B \-R \fIvarname\fP
+True if the shell variable
+.I varname
+is set and is a name reference.
+.TP
+.B \-z \fIstring\fP
+True if the length of \fIstring\fP is zero.
+.TP
+\fIstring\fP
+.PD 0
+.TP
+.B \-n \fIstring\fP
+.PD
+True if the length of
+.I string
+is non-zero.
+.TP
+\fIstring1\fP \fB==\fP \fIstring2\fP
+.PD 0
+.TP
+\fIstring1\fP \fB=\fP \fIstring2\fP
+.PD
+True if the strings are equal. \fB=\fP should be used
+with the \fBtest\fP command for POSIX conformance.
+When used with the \fB[[\fP command, this performs pattern matching as
+described above (\fBCompound Commands\fP).
+.TP
+\fIstring1\fP \fB!=\fP \fIstring2\fP
+True if the strings are not equal.
+.TP
+\fIstring1\fP \fB<\fP \fIstring2\fP
+True if \fIstring1\fP sorts before \fIstring2\fP lexicographically.
+.TP
+\fIstring1\fP \fB>\fP \fIstring2\fP
+True if \fIstring1\fP sorts after \fIstring2\fP lexicographically.
+.TP
+.I \fIarg1\fP \fBOP\fP \fIarg2\fP
+.SM
+.B OP
+is one of
+.BR \-eq ,
+.BR \-ne ,
+.BR \-lt ,
+.BR \-le ,
+.BR \-gt ,
+or
+.BR \-ge .
+These arithmetic binary operators return true if \fIarg1\fP
+is equal to, not equal to, less than, less than or equal to,
+greater than, or greater than or equal to \fIarg2\fP, respectively.
+.I Arg1
+and
+.I arg2
+may be positive or negative integers.
+.PD
+.SH "SIMPLE COMMAND EXPANSION"
+When a simple command is executed, the shell performs the following
+expansions, assignments, and redirections, from left to right.
+.IP 1.
+The words that the parser has marked as variable assignments (those
+preceding the command name) and redirections are saved for later
+processing.
+.IP 2.
+The words that are not variable assignments or redirections are
+expanded. If any words remain after expansion, the first word
+is taken to be the name of the command and the remaining words are
+the arguments.
+.IP 3.
+Redirections are performed as described above under
+.SM
+.BR REDIRECTION .
+.IP 4.
+The text after the \fB=\fP in each variable assignment undergoes tilde
+expansion, parameter expansion, command substitution, arithmetic expansion,
+and quote removal before being assigned to the variable.
+.PP
+If no command name results, the variable assignments affect the current
+shell environment. Otherwise, the variables are added to the environment
+of the executed command and do not affect the current shell environment.
+If any of the assignments attempts to assign a value to a readonly variable,
+an error occurs, and the command exits with a non-zero status.
+.PP
+If no command name results, redirections are performed, but do not
+affect the current shell environment. A redirection error causes the
+command to exit with a non-zero status.
+.PP
+If there is a command name left after expansion, execution proceeds as
+described below. Otherwise, the command exits. If one of the expansions
+contained a command substitution, the exit status of the command is
+the exit status of the last command substitution performed. If there
+were no command substitutions, the command exits with a status of zero.
+.SH "COMMAND EXECUTION"
+After a command has been split into words, if it results in a
+simple command and an optional list of arguments, the following
+actions are taken.
+.PP
+If the command name contains no slashes, the shell attempts to
+locate it. If there exists a shell function by that name, that
+function is invoked as described above in
+.SM
+.BR FUNCTIONS .
+If the name does not match a function, the shell searches for
+it in the list of shell builtins. If a match is found, that
+builtin is invoked.
+.PP
+If the name is neither a shell function nor a builtin,
+and contains no slashes,
+.B bash
+searches each element of the
+.SM
+.B PATH
+for a directory containing an executable file by that name.
+.B Bash
+uses a hash table to remember the full pathnames of executable
+files (see
+.B hash
+under
+.SM
+.B "SHELL BUILTIN COMMANDS"
+below).
+A full search of the directories in
+.SM
+.B PATH
+is performed only if the command is not found in the hash table.
+If the search is unsuccessful, the shell searches for a defined shell
+function named \fBcommand_not_found_handle\fP.
+If that function exists, it is invoked with the original command and
+the original command's arguments as its arguments, and the function's
+exit status becomes the exit status of the shell.
+If that function is not defined, the shell prints an error
+message and returns an exit status of 127.
+.PP
+If the search is successful, or if the command name contains
+one or more slashes, the shell executes the named program in a
+separate execution environment.
+Argument 0 is set to the name given, and the remaining arguments
+to the command are set to the arguments given, if any.
+.PP
+If this execution fails because the file is not in executable
+format, and the file is not a directory, it is assumed to be
+a \fIshell script\fP, a file
+containing shell commands. A subshell is spawned to execute
+it. This subshell reinitializes itself, so
+that the effect is as if a new shell had been invoked
+to handle the script, with the exception that the locations of
+commands remembered by the parent (see
+.B hash
+below under
+.SM
+\fBSHELL BUILTIN COMMANDS\fP)
+are retained by the child.
+.PP
+If the program is a file beginning with
+.BR #! ,
+the remainder of the first line specifies an interpreter
+for the program. The shell executes the
+specified interpreter on operating systems that do not
+handle this executable format themselves. The arguments to the
+interpreter consist of a single optional argument following the
+interpreter name on the first line of the program, followed
+by the name of the program, followed by the command
+arguments, if any.
+.SH COMMAND EXECUTION ENVIRONMENT
+The shell has an \fIexecution environment\fP, which consists of the
+following:
+.IP \(bu
+open files inherited by the shell at invocation, as modified by
+redirections supplied to the \fBexec\fP builtin
+.IP \(bu
+the current working directory as set by \fBcd\fP, \fBpushd\fP, or
+\fBpopd\fP, or inherited by the shell at invocation
+.IP \(bu
+the file creation mode mask as set by \fBumask\fP or inherited from
+the shell's parent
+.IP \(bu
+current traps set by \fBtrap\fP
+.IP \(bu
+shell parameters that are set by variable assignment or with \fBset\fP
+or inherited from the shell's parent in the environment
+.IP \(bu
+shell functions defined during execution or inherited from the shell's
+parent in the environment
+.IP \(bu
+options enabled at invocation (either by default or with command-line
+arguments) or by \fBset\fP
+.IP \(bu
+options enabled by \fBshopt\fP
+.IP \(bu
+shell aliases defined with \fBalias\fP
+.IP \(bu
+various process IDs, including those of background jobs, the value
+of \fB$$\fP, and the value of
+.SM
+.B PPID
+.PP
+When a simple command other than a builtin or shell function
+is to be executed, it
+is invoked in a separate execution environment that consists of
+the following. Unless otherwise noted, the values are inherited
+from the shell.
+.if n .sp 1
+.IP \(bu
+the shell's open files, plus any modifications and additions specified
+by redirections to the command
+.IP \(bu
+the current working directory
+.IP \(bu
+the file creation mode mask
+.IP \(bu
+shell variables and functions marked for export, along with variables
+exported for the command, passed in the environment
+.IP \(bu
+traps caught by the shell are reset to the values inherited from the
+shell's parent, and traps ignored by the shell are ignored
+.PP
+A command invoked in this separate environment cannot affect the
+shell's execution environment.
+.PP
+Command substitution, commands grouped with parentheses,
+and asynchronous commands are invoked in a
+subshell environment that is a duplicate of the shell environment,
+except that traps caught by the shell are reset to the values
+that the shell inherited from its parent at invocation. Builtin
+commands that are invoked as part of a pipeline are also executed in a
+subshell environment. Changes made to the subshell environment
+cannot affect the shell's execution environment.
+.PP
+Subshells spawned to execute command substitutions inherit the value of
+the \fB\-e\fP option from the parent shell. When not in \fIposix\fP mode,
+\fBbash\fP clears the \fB\-e\fP option in such subshells.
+.PP
+If a command is followed by a \fB&\fP and job control is not active, the
+default standard input for the command is the empty file \fI/dev/null\fP.
+Otherwise, the invoked command inherits the file descriptors of the calling
+shell as modified by redirections.
+.SH ENVIRONMENT
+When a program is invoked it is given an array of strings
+called the
+.IR environment .
+This is a list of
+\fIname\fP\-\fIvalue\fP pairs, of the form
+.IR "name\fR=\fPvalue" .
+.PP
+The shell provides several ways to manipulate the environment.
+On invocation, the shell scans its own environment and
+creates a parameter for each name found, automatically marking
+it for
+.I export
+to child processes. Executed commands inherit the environment.
+The
+.B export
+and
+.B declare \-x
+commands allow parameters and functions to be added to and
+deleted from the environment. If the value of a parameter
+in the environment is modified, the new value becomes part
+of the environment, replacing the old. The environment
+inherited by any executed command consists of the shell's
+initial environment, whose values may be modified in the shell,
+less any pairs removed by the
+.B unset
+command, plus any additions via the
+.B export
+and
+.B declare \-x
+commands.
+.PP
+The environment for any
+.I simple command
+or function may be augmented temporarily by prefixing it with
+parameter assignments, as described above in
+.SM
+.BR PARAMETERS .
+These assignment statements affect only the environment seen
+by that command.
+.PP
+If the
+.B \-k
+option is set (see the
+.B set
+builtin command below), then
+.I all
+parameter assignments are placed in the environment for a command,
+not just those that precede the command name.
+.PP
+When
+.B bash
+invokes an external command, the variable
+.B _
+is set to the full filename of the command and passed to that
+command in its environment.
+.SH "EXIT STATUS"
+.PP
+The exit status of an executed command is the value returned by the
+\fIwaitpid\fP system call or equivalent function. Exit statuses
+fall between 0 and 255, though, as explained below, the shell may
+use values above 125 specially. Exit statuses from shell builtins and
+compound commands are also limited to this range. Under certain
+circumstances, the shell will use special values to indicate specific
+failure modes.
+.PP
+For the shell's purposes, a command which exits with a
+zero exit status has succeeded. An exit status of zero
+indicates success. A non-zero exit status indicates failure.
+When a command terminates on a fatal signal \fIN\fP, \fBbash\fP uses
+the value of 128+\fIN\fP as the exit status.
+.PP
+If a command is not found, the child process created to
+execute it returns a status of 127. If a command is found
+but is not executable, the return status is 126.
+.PP
+If a command fails because of an error during expansion or redirection,
+the exit status is greater than zero.
+.PP
+Shell builtin commands return a status of 0 (\fItrue\fP) if
+successful, and non-zero (\fIfalse\fP) if an error occurs
+while they execute.
+All builtins return an exit status of 2 to indicate incorrect usage,
+generally invalid options or missing arguments.
+.PP
+\fBBash\fP itself returns the exit status of the last command
+executed, unless a syntax error occurs, in which case it exits
+with a non-zero value. See also the \fBexit\fP builtin
+command below.
+.SH SIGNALS
+When \fBbash\fP is interactive, in the absence of any traps, it ignores
+.SM
+.B SIGTERM
+(so that \fBkill 0\fP does not kill an interactive shell),
+and
+.SM
+.B SIGINT
+is caught and handled (so that the \fBwait\fP builtin is interruptible).
+In all cases, \fBbash\fP ignores
+.SM
+.BR SIGQUIT .
+If job control is in effect,
+.B bash
+ignores
+.SM
+.BR SIGTTIN ,
+.SM
+.BR SIGTTOU ,
+and
+.SM
+.BR SIGTSTP .
+.PP
+Non-builtin commands run by \fBbash\fP have signal handlers
+set to the values inherited by the shell from its parent.
+When job control is not in effect, asynchronous commands
+ignore
+.SM
+.B SIGINT
+and
+.SM
+.B SIGQUIT
+in addition to these inherited handlers.
+Commands run as a result of command substitution ignore the
+keyboard-generated job control signals
+.SM
+.BR SIGTTIN ,
+.SM
+.BR SIGTTOU ,
+and
+.SM
+.BR SIGTSTP .
+.PP
+The shell exits by default upon receipt of a
+.SM
+.BR SIGHUP .
+Before exiting, an interactive shell resends the
+.SM
+.B SIGHUP
+to all jobs, running or stopped.
+Stopped jobs are sent
+.SM
+.B SIGCONT
+to ensure that they receive the
+.SM
+.BR SIGHUP .
+To prevent the shell from
+sending the signal to a particular job, it should be removed from the
+jobs table with the
+.B disown
+builtin (see
+.SM
+.B "SHELL BUILTIN COMMANDS"
+below) or marked
+to not receive
+.SM
+.B SIGHUP
+using
+.BR "disown \-h" .
+.PP
+If the
+.B huponexit
+shell option has been set with
+.BR shopt ,
+.B bash
+sends a
+.SM
+.B SIGHUP
+to all jobs when an interactive login shell exits.
+.PP
+If \fBbash\fP is waiting for a command to complete and receives a signal
+for which a trap has been set, the trap will not be executed until
+the command completes.
+When \fBbash\fP is waiting for an asynchronous command via the \fBwait\fP
+builtin, the reception of a signal for which a trap has been set will
+cause the \fBwait\fP builtin to return immediately with an exit status
+greater than 128, immediately after which the trap is executed.
+.SH "JOB CONTROL"
+.I Job control
+refers to the ability to selectively stop (\fIsuspend\fP)
+the execution of processes and continue (\fIresume\fP)
+their execution at a later point. A user typically employs
+this facility via an interactive interface supplied jointly
+by the operating system kernel's terminal driver and
+.BR bash .
+.PP
+The shell associates a
+.I job
+with each pipeline. It keeps a table of currently executing
+jobs, which may be listed with the
+.B jobs
+command. When
+.B bash
+starts a job asynchronously (in the
+.IR background ),
+it prints a line that looks like:
+.RS
+.PP
+[1] 25647
+.RE
+.PP
+indicating that this job is job number 1 and that the process ID
+of the last process in the pipeline associated with this job is 25647.
+All of the processes in a single pipeline are members of the same job.
+.B Bash
+uses the
+.I job
+abstraction as the basis for job control.
+.PP
+To facilitate the implementation of the user interface to job
+control, the operating system maintains the notion of a \fIcurrent terminal
+process group ID\fP. Members of this process group (processes whose
+process group ID is equal to the current terminal process group ID)
+receive keyboard-generated signals such as
+.SM
+.BR SIGINT .
+These processes are said to be in the
+.IR foreground .
+.I Background
+processes are those whose process group ID differs from the terminal's;
+such processes are immune to keyboard-generated signals.
+Only foreground processes are allowed to read from or, if the
+user so specifies with \f(CWstty tostop\fP, write to the
+terminal.
+Background processes which attempt to read from (write to when
+\f(CWstty tostop\fP is in effect) the
+terminal are sent a
+.SM
+.B SIGTTIN (SIGTTOU)
+signal by the kernel's terminal driver,
+which, unless caught, suspends the process.
+.PP
+If the operating system on which
+.B bash
+is running supports
+job control,
+.B bash
+contains facilities to use it.
+Typing the
+.I suspend
+character (typically
+.BR ^Z ,
+Control-Z) while a process is running
+causes that process to be stopped and returns control to
+.BR bash .
+Typing the
+.I "delayed suspend"
+character (typically
+.BR ^Y ,
+Control-Y) causes the process to be stopped when it
+attempts to read input from the terminal, and control to
+be returned to
+.BR bash .
+The user may then manipulate the state of this job, using the
+.B bg
+command to continue it in the background, the
+.B fg
+command to continue it in the foreground, or
+the
+.B kill
+command to kill it. A \fB^Z\fP takes effect immediately,
+and has the additional side effect of causing pending output
+and typeahead to be discarded.
+.PP
+There are a number of ways to refer to a job in the shell.
+The character
+.B %
+introduces a job specification (\fIjobspec\fP). Job number
+.I n
+may be referred to as
+.BR %n .
+A job may also be referred to using a prefix of the name used to
+start it, or using a substring that appears in its command line.
+For example,
+.B %ce
+refers to a stopped
+.B ce
+job. If a prefix matches more than one job,
+.B bash
+reports an error. Using
+.BR %?ce ,
+on the other hand, refers to any job containing the string
+.B ce
+in its command line. If the substring matches more than one job,
+.B bash
+reports an error. The symbols
+.B %%
+and
+.B %+
+refer to the shell's notion of the
+.IR "current job" ,
+which is the last job stopped while it was in
+the foreground or started in the background.
+The
+.I "previous job"
+may be referenced using
+.BR %\- .
+If there is only a single job, \fB%+\fP and \fB%\-\fP can both be used
+to refer to that job.
+In output pertaining to jobs (e.g., the output of the
+.B jobs
+command), the current job is always flagged with a
+.BR + ,
+and the previous job with a
+.BR \- .
+A single % (with no accompanying job specification) also refers to the
+current job.
+.PP
+Simply naming a job can be used to bring it into the
+foreground:
+.B %1
+is a synonym for
+\fB``fg %1''\fP,
+bringing job 1 from the background into the foreground.
+Similarly,
+.B ``%1 &''
+resumes job 1 in the background, equivalent to
+\fB``bg %1''\fP.
+.PP
+The shell learns immediately whenever a job changes state.
+Normally,
+.B bash
+waits until it is about to print a prompt before reporting
+changes in a job's status so as to not interrupt
+any other output. If the
+.B \-b
+option to the
+.B set
+builtin command
+is enabled,
+.B bash
+reports such changes immediately.
+Any trap on
+.SM
+.B SIGCHLD
+is executed for each child that exits.
+.PP
+If an attempt to exit
+.B bash
+is made while jobs are stopped (or, if the \fBcheckjobs\fP shell option has
+been enabled using the \fBshopt\fP builtin, running), the shell prints a
+warning message, and, if the \fBcheckjobs\fP option is enabled, lists the
+jobs and their statuses.
+The
+.B jobs
+command may then be used to inspect their status.
+If a second attempt to exit is made without an intervening command,
+the shell does not print another warning, and any stopped
+jobs are terminated.
+.SH PROMPTING
+When executing interactively,
+.B bash
+displays the primary prompt
+.SM
+.B PS1
+when it is ready to read a command, and the secondary prompt
+.SM
+.B PS2
+when it needs more input to complete a command.
+.B Bash
+allows these prompt strings to be customized by inserting a number of
+backslash-escaped special characters that are decoded as follows:
+.RS
+.PD 0
+.TP
+.B \ea
+an ASCII bell character (07)
+.TP
+.B \ed
+the date in "Weekday Month Date" format (e.g., "Tue May 26")
+.TP
+.B \eD{\fIformat\fP}
+the \fIformat\fP is passed to \fIstrftime\fP(3) and the result is inserted
+into the prompt string; an empty \fIformat\fP results in a locale-specific
+time representation. The braces are required
+.TP
+.B \ee
+an ASCII escape character (033)
+.TP
+.B \eh
+the hostname up to the first `.'
+.TP
+.B \eH
+the hostname
+.TP
+.B \ej
+the number of jobs currently managed by the shell
+.TP
+.B \el
+the basename of the shell's terminal device name
+.TP
+.B \en
+newline
+.TP
+.B \er
+carriage return
+.TP
+.B \es
+the name of the shell, the basename of
+.B $0
+(the portion following the final slash)
+.TP
+.B \et
+the current time in 24-hour HH:MM:SS format
+.TP
+.B \eT
+the current time in 12-hour HH:MM:SS format
+.TP
+.B \e@
+the current time in 12-hour am/pm format
+.TP
+.B \eA
+the current time in 24-hour HH:MM format
+.TP
+.B \eu
+the username of the current user
+.TP
+.B \ev
+the version of \fBbash\fP (e.g., 2.00)
+.TP
+.B \eV
+the release of \fBbash\fP, version + patch level (e.g., 2.00.0)
+.TP
+.B \ew
+the current working directory, with
+.SM
+.B $HOME
+abbreviated with a tilde
+(uses the value of the
+.SM
+.B PROMPT_DIRTRIM
+variable)
+.TP
+.B \eW
+the basename of the current working directory, with
+.SM
+.B $HOME
+abbreviated with a tilde
+.TP
+.B \e!
+the history number of this command
+.TP
+.B \e#
+the command number of this command
+.TP
+.B \e$
+if the effective UID is 0, a
+.BR # ,
+otherwise a
+.B $
+.TP
+.B \e\fInnn\fP
+the character corresponding to the octal number \fInnn\fP
+.TP
+.B \e\e
+a backslash
+.TP
+.B \e[
+begin a sequence of non-printing characters, which could be used to
+embed a terminal control sequence into the prompt
+.TP
+.B \e]
+end a sequence of non-printing characters
+.PD
+.RE
+.PP
+The command number and the history number are usually different:
+the history number of a command is its position in the history
+list, which may include commands restored from the history file
+(see
+.SM
+.B HISTORY
+below), while the command number is the position in the sequence
+of commands executed during the current shell session.
+After the string is decoded, it is expanded via
+parameter expansion, command substitution, arithmetic
+expansion, and quote removal, subject to the value of the
+.B promptvars
+shell option (see the description of the
+.B shopt
+command under
+.SM
+.B "SHELL BUILTIN COMMANDS"
+below).
+.SH READLINE
+This is the library that handles reading input when using an interactive
+shell, unless the
+.B \-\-noediting
+option is given at shell invocation.
+Line editing is also used when using the \fB\-e\fP option to the
+\fBread\fP builtin.
+By default, the line editing commands are similar to those of Emacs.
+A vi-style line editing interface is also available.
+Line editing can be enabled at any time using the
+.B \-o emacs
+or
+.B \-o vi
+options to the
+.B set
+builtin (see
+.SM
+.B SHELL BUILTIN COMMANDS
+below).
+To turn off line editing after the shell is running, use the
+.B +o emacs
+or
+.B +o vi
+options to the
+.B set
+builtin.
+.SS "Readline Notation"
+.PP
+In this section, the Emacs-style notation is used to denote
+keystrokes. Control keys are denoted by C\-\fIkey\fR, e.g., C\-n
+means Control\-N. Similarly,
+.I meta
+keys are denoted by M\-\fIkey\fR, so M\-x means Meta\-X. (On keyboards
+without a
+.I meta
+key, M\-\fIx\fP means ESC \fIx\fP, i.e., press the Escape key
+then the
+.I x
+key. This makes ESC the \fImeta prefix\fP.
+The combination M\-C\-\fIx\fP means ESC\-Control\-\fIx\fP,
+or press the Escape key
+then hold the Control key while pressing the
+.I x
+key.)
+.PP
+Readline commands may be given numeric
+.IR arguments ,
+which normally act as a repeat count.
+Sometimes, however, it is the sign of the argument that is significant.
+Passing a negative argument to a command that acts in the forward
+direction (e.g., \fBkill\-line\fP) causes that command to act in a
+backward direction.
+Commands whose behavior with arguments deviates from this are noted
+below.
+.PP
+When a command is described as \fIkilling\fP text, the text
+deleted is saved for possible future retrieval
+(\fIyanking\fP). The killed text is saved in a
+\fIkill ring\fP. Consecutive kills cause the text to be
+accumulated into one unit, which can be yanked all at once.
+Commands which do not kill text separate the chunks of text
+on the kill ring.
+.SS "Readline Initialization"
+.PP
+Readline is customized by putting commands in an initialization
+file (the \fIinputrc\fP file).
+The name of this file is taken from the value of the
+.SM
+.B INPUTRC
+variable. If that variable is unset, the default is
+.IR ~/.inputrc .
+When a program which uses the readline library starts up, the
+initialization file is read, and the key bindings and variables
+are set.
+There are only a few basic constructs allowed in the
+readline initialization file.
+Blank lines are ignored.
+Lines beginning with a \fB#\fP are comments.
+Lines beginning with a \fB$\fP indicate conditional constructs.
+Other lines denote key bindings and variable settings.
+.PP
+The default key-bindings may be changed with an
+.I inputrc
+file.
+Other programs that use this library may add their own commands
+and bindings.
+.PP
+For example, placing
+.RS
+.PP
+M\-Control\-u: universal\-argument
+.RE
+or
+.RS
+C\-Meta\-u: universal\-argument
+.RE
+into the
+.I inputrc
+would make M\-C\-u execute the readline command
+.IR universal\-argument .
+.PP
+The following symbolic character names are recognized:
+.IR RUBOUT ,
+.IR DEL ,
+.IR ESC ,
+.IR LFD ,
+.IR NEWLINE ,
+.IR RET ,
+.IR RETURN ,
+.IR SPC ,
+.IR SPACE ,
+and
+.IR TAB .
+.PP
+In addition to command names, readline allows keys to be bound
+to a string that is inserted when the key is pressed (a \fImacro\fP).
+.SS "Readline Key Bindings"
+.PP
+The syntax for controlling key bindings in the
+.I inputrc
+file is simple. All that is required is the name of the
+command or the text of a macro and a key sequence to which
+it should be bound. The name may be specified in one of two ways:
+as a symbolic key name, possibly with \fIMeta\-\fP or \fIControl\-\fP
+prefixes, or as a key sequence.
+.PP
+When using the form \fBkeyname\fP:\^\fIfunction\-name\fP or \fImacro\fP,
+.I keyname
+is the name of a key spelled out in English. For example:
+.sp
+.RS
+Control-u: universal\-argument
+.br
+Meta-Rubout: backward-kill-word
+.br
+Control-o: "> output"
+.RE
+.LP
+In the above example,
+.I C\-u
+is bound to the function
+.BR universal\-argument ,
+.I M\-DEL
+is bound to the function
+.BR backward\-kill\-word ,
+and
+.I C\-o
+is bound to run the macro
+expressed on the right hand side (that is, to insert the text
+.if t \f(CW> output\fP
+.if n ``> output''
+into the line).
+.PP
+In the second form, \fB"keyseq"\fP:\^\fIfunction\-name\fP or \fImacro\fP,
+.B keyseq
+differs from
+.B keyname
+above in that strings denoting
+an entire key sequence may be specified by placing the sequence
+within double quotes. Some GNU Emacs style key escapes can be
+used, as in the following example, but the symbolic character names
+are not recognized.
+.sp
+.RS
+"\eC\-u": universal\-argument
+.br
+"\eC\-x\eC\-r": re\-read\-init\-file
+.br
+"\ee[11~": "Function Key 1"
+.RE
+.PP
+In this example,
+.I C\-u
+is again bound to the function
+.BR universal\-argument .
+.I "C\-x C\-r"
+is bound to the function
+.BR re\-read\-init\-file ,
+and
+.I "ESC [ 1 1 ~"
+is bound to insert the text
+.if t \f(CWFunction Key 1\fP.
+.if n ``Function Key 1''.
+.PP
+The full set of GNU Emacs style escape sequences is
+.RS
+.PD 0
+.TP
+.B \eC\-
+control prefix
+.TP
+.B \eM\-
+meta prefix
+.TP
+.B \ee
+an escape character
+.TP
+.B \e\e
+backslash
+.TP
+.B \e"
+literal "
+.TP
+.B \e\(aq
+literal \(aq
+.RE
+.PD
+.PP
+In addition to the GNU Emacs style escape sequences, a second
+set of backslash escapes is available:
+.RS
+.PD 0
+.TP
+.B \ea
+alert (bell)
+.TP
+.B \eb
+backspace
+.TP
+.B \ed
+delete
+.TP
+.B \ef
+form feed
+.TP
+.B \en
+newline
+.TP
+.B \er
+carriage return
+.TP
+.B \et
+horizontal tab
+.TP
+.B \ev
+vertical tab
+.TP
+.B \e\fInnn\fP
+the eight-bit character whose value is the octal value \fInnn\fP
+(one to three digits)
+.TP
+.B \ex\fIHH\fP
+the eight-bit character whose value is the hexadecimal value \fIHH\fP
+(one or two hex digits)
+.RE
+.PD
+.PP
+When entering the text of a macro, single or double quotes must
+be used to indicate a macro definition.
+Unquoted text is assumed to be a function name.
+In the macro body, the backslash escapes described above are expanded.
+Backslash will quote any other character in the macro text,
+including " and \(aq.
+.PP
+.B Bash
+allows the current readline key bindings to be displayed or modified
+with the
+.B bind
+builtin command. The editing mode may be switched during interactive
+use by using the
+.B \-o
+option to the
+.B set
+builtin command (see
+.SM
+.B SHELL BUILTIN COMMANDS
+below).
+.SS "Readline Variables"
+.PP
+Readline has variables that can be used to further customize its
+behavior. A variable may be set in the
+.I inputrc
+file with a statement of the form
+.RS
+.PP
+\fBset\fP \fIvariable\-name\fP \fIvalue\fP
+.RE
+.PP
+Except where noted, readline variables can take the values
+.B On
+or
+.B Off
+(without regard to case).
+Unrecognized variable names are ignored.
+When a variable value is read, empty or null values, "on" (case-insensitive),
+and "1" are equivalent to \fBOn\fP. All other values are equivalent to
+\fBOff\fP.
+The variables and their default values are:
+.PP
+.PD 0
+.TP
+.B bell\-style (audible)
+Controls what happens when readline wants to ring the terminal bell.
+If set to \fBnone\fP, readline never rings the bell. If set to
+\fBvisible\fP, readline uses a visible bell if one is available.
+If set to \fBaudible\fP, readline attempts to ring the terminal's bell.
+.TP
+.B bind\-tty\-special\-chars (On)
+If set to \fBOn\fP, readline attempts to bind the control characters
+treated specially by the kernel's terminal driver to their readline
+equivalents.
+.TP
+.B colored\-completion\-prefix (Off)
+If set to \fBOn\fP, when listing completions, readline displays the
+common prefix of the set of possible completions using a different color.
+The color definitions are taken from the value of the \fBLS_COLORS\fP
+environment variable.
+.TP
+.B colored\-stats (Off)
+If set to \fBOn\fP, readline displays possible completions using different
+colors to indicate their file type.
+The color definitions are taken from the value of the \fBLS_COLORS\fP
+environment variable.
+.TP
+.B comment\-begin (``#'')
+The string that is inserted when the readline
+.B insert\-comment
+command is executed.
+This command is bound to
+.B M\-#
+in emacs mode and to
+.B #
+in vi command mode.
+.TP
+.B completion\-ignore\-case (Off)
+If set to \fBOn\fP, readline performs filename matching and completion
+in a case\-insensitive fashion.
+.TP
+.B completion\-prefix\-display\-length (0)
+The length in characters of the common prefix of a list of possible
+completions that is displayed without modification. When set to a
+value greater than zero, common prefixes longer than this value are
+replaced with an ellipsis when displaying possible completions.
+.TP
+.B completion\-query\-items (100)
+This determines when the user is queried about viewing
+the number of possible completions
+generated by the \fBpossible\-completions\fP command.
+It may be set to any integer value greater than or equal to
+zero. If the number of possible completions is greater than
+or equal to the value of this variable, the user is asked whether
+or not he wishes to view them; otherwise they are simply listed
+on the terminal.
+.TP
+.B convert\-meta (On)
+If set to \fBOn\fP, readline will convert characters with the
+eighth bit set to an ASCII key sequence
+by stripping the eighth bit and prefixing an
+escape character (in effect, using escape as the \fImeta prefix\fP).
+.TP
+.B disable\-completion (Off)
+If set to \fBOn\fP, readline will inhibit word completion. Completion
+characters will be inserted into the line as if they had been
+mapped to \fBself-insert\fP.
+.TP
+.B editing\-mode (emacs)
+Controls whether readline begins with a set of key bindings similar
+to \fIEmacs\fP or \fIvi\fP.
+.B editing\-mode
+can be set to either
+.B emacs
+or
+.BR vi .
+.TP
+.B echo\-control\-characters (On)
+When set to \fBOn\fP, on operating systems that indicate they support it,
+readline echoes a character corresponding to a signal generated from the
+keyboard.
+.TP
+.B enable\-bracketed\-paste (Off)
+When set to \fBOn\fP, readline will configure the terminal in a way
+that will enable it to insert each paste into the editing buffer as a
+single string of characters, instead of treating each character as if
+it had been read from the keyboard. This can prevent pasted characters
+from being interpreted as editing commands.
+.TP
+.B enable\-keypad (Off)
+When set to \fBOn\fP, readline will try to enable the application
+keypad when it is called. Some systems need this to enable the
+arrow keys.
+.TP
+.B enable\-meta\-key (On)
+When set to \fBOn\fP, readline will try to enable any meta modifier
+key the terminal claims to support when it is called. On many terminals,
+the meta key is used to send eight-bit characters.
+.TP
+.B expand\-tilde (Off)
+If set to \fBOn\fP, tilde expansion is performed when readline
+attempts word completion.
+.TP
+.B history\-preserve\-point (Off)
+If set to \fBOn\fP, the history code attempts to place point at the
+same location on each history line retrieved with \fBprevious-history\fP
+or \fBnext-history\fP.
+.TP
+.B history\-size (unset)
+Set the maximum number of history entries saved in the history list.
+If set to zero, any existing history entries are deleted and no new entries
+are saved.
+If set to a value less than zero, the number of history entries is not
+limited.
+By default, the number of history entries is not limited.
+.TP
+.B horizontal\-scroll\-mode (Off)
+When set to \fBOn\fP, makes readline use a single line for display,
+scrolling the input horizontally on a single screen line when it
+becomes longer than the screen width rather than wrapping to a new line.
+.TP
+.B input\-meta (Off)
+If set to \fBOn\fP, readline will enable eight-bit input (that is,
+it will not strip the high bit from the characters it reads),
+regardless of what the terminal claims it can support. The name
+.B meta\-flag
+is a synonym for this variable.
+.TP
+.B isearch\-terminators (``C\-[C\-J'')
+The string of characters that should terminate an incremental
+search without subsequently executing the character as a command.
+If this variable has not been given a value, the characters
+\fIESC\fP and \fIC\-J\fP will terminate an incremental search.
+.TP
+.B keymap (emacs)
+Set the current readline keymap. The set of valid keymap names is
+\fIemacs, emacs\-standard, emacs\-meta, emacs\-ctlx, vi,
+vi\-command\fP, and
+.IR vi\-insert .
+\fIvi\fP is equivalent to \fIvi\-command\fP; \fIemacs\fP is
+equivalent to \fIemacs\-standard\fP. The default value is
+.IR emacs ;
+the value of
+.B editing\-mode
+also affects the default keymap.
+.TP
+.B emacs\-mode\-string (@)
+This string is displayed immediately before the last line of the primary
+prompt when emacs editing mode is active. The value is expanded like a
+key binding, so the standard set of meta- and control prefixes and
+backslash escape sequences is available.
+Use the \e1 and \e2 escapes to begin and end sequences of
+non-printing characters, which can be used to embed a terminal control
+sequence into the mode string.
+.TP
+.B keyseq\-timeout (500)
+Specifies the duration \fIreadline\fP will wait for a character when reading an
+ambiguous key sequence (one that can form a complete key sequence using
+the input read so far, or can take additional input to complete a longer
+key sequence).
+If no input is received within the timeout, \fIreadline\fP will use the shorter
+but complete key sequence.
+The value is specified in milliseconds, so a value of 1000 means that
+\fIreadline\fP will wait one second for additional input.
+If this variable is set to a value less than or equal to zero, or to a
+non-numeric value, \fIreadline\fP will wait until another key is pressed to
+decide which key sequence to complete.
+.TP
+.B mark\-directories (On)
+If set to \fBOn\fP, completed directory names have a slash
+appended.
+.TP
+.B mark\-modified\-lines (Off)
+If set to \fBOn\fP, history lines that have been modified are displayed
+with a preceding asterisk (\fB*\fP).
+.TP
+.B mark\-symlinked\-directories (Off)
+If set to \fBOn\fP, completed names which are symbolic links to directories
+have a slash appended (subject to the value of
+\fBmark\-directories\fP).
+.TP
+.B match\-hidden\-files (On)
+This variable, when set to \fBOn\fP, causes readline to match files whose
+names begin with a `.' (hidden files) when performing filename
+completion.
+If set to \fBOff\fP, the leading `.' must be
+supplied by the user in the filename to be completed.
+.TP
+.B menu\-complete\-display\-prefix (Off)
+If set to \fBOn\fP, menu completion displays the common prefix of the
+list of possible completions (which may be empty) before cycling through
+the list.
+.TP
+.B output\-meta (Off)
+If set to \fBOn\fP, readline will display characters with the
+eighth bit set directly rather than as a meta-prefixed escape
+sequence.
+.TP
+.B page\-completions (On)
+If set to \fBOn\fP, readline uses an internal \fImore\fP-like pager
+to display a screenful of possible completions at a time.
+.TP
+.B print\-completions\-horizontally (Off)
+If set to \fBOn\fP, readline will display completions with matches
+sorted horizontally in alphabetical order, rather than down the screen.
+.TP
+.B revert\-all\-at\-newline (Off)
+If set to \fBOn\fP, readline will undo all changes to history lines
+before returning when \fBaccept\-line\fP is executed. By default,
+history lines may be modified and retain individual undo lists across
+calls to \fBreadline\fP.
+.TP
+.B show\-all\-if\-ambiguous (Off)
+This alters the default behavior of the completion functions. If
+set to
+.BR On ,
+words which have more than one possible completion cause the
+matches to be listed immediately instead of ringing the bell.
+.TP
+.B show\-all\-if\-unmodified (Off)
+This alters the default behavior of the completion functions in
+a fashion similar to \fBshow\-all\-if\-ambiguous\fP.
+If set to
+.BR On ,
+words which have more than one possible completion without any
+possible partial completion (the possible completions don't share
+a common prefix) cause the matches to be listed immediately instead
+of ringing the bell.
+.TP
+.B show\-mode\-in\-prompt (Off)
+If set to \fBOn\fP, add a character to the beginning of the prompt
+indicating the editing mode: emacs (@), vi command (:) or vi
+insertion (+).
+.TP
+.B skip\-completed\-text (Off)
+If set to \fBOn\fP, this alters the default completion behavior when
+inserting a single match into the line. It's only active when
+performing completion in the middle of a word. If enabled, readline
+does not insert characters from the completion that match characters
+after point in the word being completed, so portions of the word
+following the cursor are not duplicated.
+.TP
+.B vi\-cmd\-mode\-string ((cmd))
+This string is displayed immediately before the last line of the primary
+prompt when vi editing mode is active and in command mode.
+The value is expanded like a
+key binding, so the standard set of meta- and control prefixes and
+backslash escape sequences is available.
+Use the \e1 and \e2 escapes to begin and end sequences of
+non-printing characters, which can be used to embed a terminal control
+sequence into the mode string.
+.TP
+.B vi\-ins\-mode\-string ((ins))
+This string is displayed immediately before the last line of the primary
+prompt when vi editing mode is active and in insertion mode.
+The value is expanded like a
+key binding, so the standard set of meta- and control prefixes and
+backslash escape sequences is available.
+Use the \e1 and \e2 escapes to begin and end sequences of
+non-printing characters, which can be used to embed a terminal control
+sequence into the mode string.
+.TP
+.B visible\-stats (Off)
+If set to \fBOn\fP, a character denoting a file's type as reported
+by \fIstat\fP(2) is appended to the filename when listing possible
+completions.
+.PD
+.SS "Readline Conditional Constructs"
+.PP
+Readline implements a facility similar in spirit to the conditional
+compilation features of the C preprocessor which allows key
+bindings and variable settings to be performed as the result
+of tests. There are four parser directives used.
+.IP \fB$if\fP
+The
+.B $if
+construct allows bindings to be made based on the
+editing mode, the terminal being used, or the application using
+readline. The text of the test extends to the end of the line;
+no characters are required to isolate it.
+.RS
+.IP \fBmode\fP
+The \fBmode=\fP form of the \fB$if\fP directive is used to test
+whether readline is in emacs or vi mode.
+This may be used in conjunction
+with the \fBset keymap\fP command, for instance, to set bindings in
+the \fIemacs\-standard\fP and \fIemacs\-ctlx\fP keymaps only if
+readline is starting out in emacs mode.
+.IP \fBterm\fP
+The \fBterm=\fP form may be used to include terminal-specific
+key bindings, perhaps to bind the key sequences output by the
+terminal's function keys. The word on the right side of the
+.B =
+is tested against the both full name of the terminal and the portion
+of the terminal name before the first \fB\-\fP. This allows
+.I sun
+to match both
+.I sun
+and
+.IR sun\-cmd ,
+for instance.
+.IP \fBapplication\fP
+The \fBapplication\fP construct is used to include
+application-specific settings. Each program using the readline
+library sets the \fIapplication name\fP, and an initialization
+file can test for a particular value.
+This could be used to bind key sequences to functions useful for
+a specific program. For instance, the following command adds a
+key sequence that quotes the current or previous word in \fBbash\fP:
+.sp 1
+.RS
+.nf
+\fB$if\fP Bash
+# Quote the current or previous word
+"\eC\-xq": "\eeb\e"\eef\e""
+\fB$endif\fP
+.fi
+.RE
+.RE
+.IP \fB$endif\fP
+This command, as seen in the previous example, terminates an
+\fB$if\fP command.
+.IP \fB$else\fP
+Commands in this branch of the \fB$if\fP directive are executed if
+the test fails.
+.IP \fB$include\fP
+This directive takes a single filename as an argument and reads commands
+and bindings from that file. For example, the following directive
+would read \fI/etc/inputrc\fP:
+.sp 1
+.RS
+.nf
+\fB$include\fP \^ \fI/etc/inputrc\fP
+.fi
+.RE
+.SS Searching
+.PP
+Readline provides commands for searching through the command history
+(see
+.SM
+.B HISTORY
+below) for lines containing a specified string.
+There are two search modes:
+.I incremental
+and
+.IR non-incremental .
+.PP
+Incremental searches begin before the user has finished typing the
+search string.
+As each character of the search string is typed, readline displays
+the next entry from the history matching the string typed so far.
+An incremental search requires only as many characters as needed to
+find the desired history entry.
+The characters present in the value of the \fBisearch-terminators\fP
+variable are used to terminate an incremental search.
+If that variable has not been assigned a value the Escape and
+Control-J characters will terminate an incremental search.
+Control-G will abort an incremental search and restore the original
+line.
+When the search is terminated, the history entry containing the
+search string becomes the current line.
+.PP
+To find other matching entries in the history list, type Control-S or
+Control-R as appropriate.
+This will search backward or forward in the history for the next
+entry matching the search string typed so far.
+Any other key sequence bound to a readline command will terminate
+the search and execute that command.
+For instance, a \fInewline\fP will terminate the search and accept
+the line, thereby executing the command from the history list.
+.PP
+Readline remembers the last incremental search string. If two
+Control-Rs are typed without any intervening characters defining a
+new search string, any remembered search string is used.
+.PP
+Non-incremental searches read the entire search string before starting
+to search for matching history lines. The search string may be
+typed by the user or be part of the contents of the current line.
+.SS "Readline Command Names"
+.PP
+The following is a list of the names of the commands and the default
+key sequences to which they are bound.
+Command names without an accompanying key sequence are unbound by default.
+In the following descriptions, \fIpoint\fP refers to the current cursor
+position, and \fImark\fP refers to a cursor position saved by the
+\fBset\-mark\fP command.
+The text between the point and mark is referred to as the \fIregion\fP.
+.SS Commands for Moving
+.PP
+.PD 0
+.TP
+.B beginning\-of\-line (C\-a)
+Move to the start of the current line.
+.TP
+.B end\-of\-line (C\-e)
+Move to the end of the line.
+.TP
+.B forward\-char (C\-f)
+Move forward a character.
+.TP
+.B backward\-char (C\-b)
+Move back a character.
+.TP
+.B forward\-word (M\-f)
+Move forward to the end of the next word. Words are composed of
+alphanumeric characters (letters and digits).
+.TP
+.B backward\-word (M\-b)
+Move back to the start of the current or previous word.
+Words are composed of alphanumeric characters (letters and digits).
+.TP
+.B shell\-forward\-word
+Move forward to the end of the next word.
+Words are delimited by non-quoted shell metacharacters.
+.TP
+.B shell\-backward\-word
+Move back to the start of the current or previous word.
+Words are delimited by non-quoted shell metacharacters.
+.TP
+.B clear\-screen (C\-l)
+Clear the screen leaving the current line at the top of the screen.
+With an argument, refresh the current line without clearing the
+screen.
+.TP
+.B redraw\-current\-line
+Refresh the current line.
+.PD
+.SS Commands for Manipulating the History
+.PP
+.PD 0
+.TP
+.B accept\-line (Newline, Return)
+Accept the line regardless of where the cursor is. If this line is
+non-empty, add it to the history list according to the state of the
+.SM
+.B HISTCONTROL
+variable. If the line is a modified history
+line, then restore the history line to its original state.
+.TP
+.B previous\-history (C\-p)
+Fetch the previous command from the history list, moving back in
+the list.
+.TP
+.B next\-history (C\-n)
+Fetch the next command from the history list, moving forward in the
+list.
+.TP
+.B beginning\-of\-history (M\-<)
+Move to the first line in the history.
+.TP
+.B end\-of\-history (M\->)
+Move to the end of the input history, i.e., the line currently being
+entered.
+.TP
+.B reverse\-search\-history (C\-r)
+Search backward starting at the current line and moving `up' through
+the history as necessary. This is an incremental search.
+.TP
+.B forward\-search\-history (C\-s)
+Search forward starting at the current line and moving `down' through
+the history as necessary. This is an incremental search.
+.TP
+.B non\-incremental\-reverse\-search\-history (M\-p)
+Search backward through the history starting at the current line
+using a non-incremental search for a string supplied by the user.
+.TP
+.B non\-incremental\-forward\-search\-history (M\-n)
+Search forward through the history using a non-incremental search for
+a string supplied by the user.
+.TP
+.B history\-search\-forward
+Search forward through the history for the string of characters
+between the start of the current line and the point.
+This is a non-incremental search.
+.TP
+.B history\-search\-backward
+Search backward through the history for the string of characters
+between the start of the current line and the point.
+This is a non-incremental search.
+.TP
+.B yank\-nth\-arg (M\-C\-y)
+Insert the first argument to the previous command (usually
+the second word on the previous line) at point.
+With an argument
+.IR n ,
+insert the \fIn\fPth word from the previous command (the words
+in the previous command begin with word 0). A negative argument
+inserts the \fIn\fPth word from the end of the previous command.
+Once the argument \fIn\fP is computed, the argument is extracted
+as if the "!\fIn\fP" history expansion had been specified.
+.TP
+.B
+yank\-last\-arg (M\-.\^, M\-_\^)
+Insert the last argument to the previous command (the last word of
+the previous history entry).
+With a numeric argument, behave exactly like \fByank\-nth\-arg\fP.
+Successive calls to \fByank\-last\-arg\fP move back through the history
+list, inserting the last word (or the word specified by the argument to
+the first call) of each line in turn.
+Any numeric argument supplied to these successive calls determines
+the direction to move through the history. A negative argument switches
+the direction through the history (back or forward).
+The history expansion facilities are used to extract the last word,
+as if the "!$" history expansion had been specified.
+.TP
+.B shell\-expand\-line (M\-C\-e)
+Expand the line as the shell does. This
+performs alias and history expansion as well as all of the shell
+word expansions. See
+.SM
+.B HISTORY EXPANSION
+below for a description of history expansion.
+.TP
+.B history\-expand\-line (M\-^)
+Perform history expansion on the current line.
+See
+.SM
+.B HISTORY EXPANSION
+below for a description of history expansion.
+.TP
+.B magic\-space
+Perform history expansion on the current line and insert a space.
+See
+.SM
+.B HISTORY EXPANSION
+below for a description of history expansion.
+.TP
+.B alias\-expand\-line
+Perform alias expansion on the current line.
+See
+.SM
+.B ALIASES
+above for a description of alias expansion.
+.TP
+.B history\-and\-alias\-expand\-line
+Perform history and alias expansion on the current line.
+.TP
+.B insert\-last\-argument (M\-.\^, M\-_\^)
+A synonym for \fByank\-last\-arg\fP.
+.TP
+.B operate\-and\-get\-next (C\-o)
+Accept the current line for execution and fetch the next line
+relative to the current line from the history for editing. Any
+argument is ignored.
+.TP
+.B edit\-and\-execute\-command (C\-xC\-e)
+Invoke an editor on the current command line, and execute the result as shell
+commands.
+\fBBash\fP attempts to invoke
+.SM
+.BR $VISUAL ,
+.SM
+.BR $EDITOR ,
+and \fIemacs\fP as the editor, in that order.
+.PD
+.SS Commands for Changing Text
+.PP
+.PD 0
+.TP
+.B \fIend\-of\-file\fP (usually C\-d)
+The character indicating end-of-file as set, for example, by
+.if t \f(CWstty\fP.
+.if n ``stty''.
+If this character is read when there are no characters
+on the line, and point is at the beginning of the line, Readline
+interprets it as the end of input and returns
+.SM
+.BR EOF .
+.TP
+.B delete\-char (C\-d)
+Delete the character at point.
+If this function is bound to the
+same character as the tty \fBEOF\fP character, as \fBC\-d\fP
+commonly is, see above for the effects.
+.TP
+.B backward\-delete\-char (Rubout)
+Delete the character behind the cursor. When given a numeric argument,
+save the deleted text on the kill ring.
+.TP
+.B forward\-backward\-delete\-char
+Delete the character under the cursor, unless the cursor is at the
+end of the line, in which case the character behind the cursor is
+deleted.
+.TP
+.B quoted\-insert (C\-q, C\-v)
+Add the next character typed to the line verbatim. This is
+how to insert characters like \fBC\-q\fP, for example.
+.TP
+.B tab\-insert (C\-v TAB)
+Insert a tab character.
+.TP
+.B self\-insert (a,\ b,\ A,\ 1,\ !,\ ...)
+Insert the character typed.
+.TP
+.B transpose\-chars (C\-t)
+Drag the character before point forward over the character at point,
+moving point forward as well.
+If point is at the end of the line, then this transposes
+the two characters before point.
+Negative arguments have no effect.
+.TP
+.B transpose\-words (M\-t)
+Drag the word before point past the word after point,
+moving point over that word as well.
+If point is at the end of the line, this transposes
+the last two words on the line.
+.TP
+.B upcase\-word (M\-u)
+Uppercase the current (or following) word. With a negative argument,
+uppercase the previous word, but do not move point.
+.TP
+.B downcase\-word (M\-l)
+Lowercase the current (or following) word. With a negative argument,
+lowercase the previous word, but do not move point.
+.TP
+.B capitalize\-word (M\-c)
+Capitalize the current (or following) word. With a negative argument,
+capitalize the previous word, but do not move point.
+.TP
+.B overwrite\-mode
+Toggle overwrite mode. With an explicit positive numeric argument,
+switches to overwrite mode. With an explicit non-positive numeric
+argument, switches to insert mode. This command affects only
+\fBemacs\fP mode; \fBvi\fP mode does overwrite differently.
+Each call to \fIreadline()\fP starts in insert mode.
+In overwrite mode, characters bound to \fBself\-insert\fP replace
+the text at point rather than pushing the text to the right.
+Characters bound to \fBbackward\-delete\-char\fP replace the character
+before point with a space. By default, this command is unbound.
+.PD
+.SS Killing and Yanking
+.PP
+.PD 0
+.TP
+.B kill\-line (C\-k)
+Kill the text from point to the end of the line.
+.TP
+.B backward\-kill\-line (C\-x Rubout)
+Kill backward to the beginning of the line.
+.TP
+.B unix\-line\-discard (C\-u)
+Kill backward from point to the beginning of the line.
+The killed text is saved on the kill-ring.
+.\" There is no real difference between this and backward-kill-line
+.TP
+.B kill\-whole\-line
+Kill all characters on the current line, no matter where point is.
+.TP
+.B kill\-word (M\-d)
+Kill from point to the end of the current word, or if between
+words, to the end of the next word.
+Word boundaries are the same as those used by \fBforward\-word\fP.
+.TP
+.B backward\-kill\-word (M\-Rubout)
+Kill the word behind point.
+Word boundaries are the same as those used by \fBbackward\-word\fP.
+.TP
+.B shell\-kill\-word
+Kill from point to the end of the current word, or if between
+words, to the end of the next word.
+Word boundaries are the same as those used by \fBshell\-forward\-word\fP.
+.TP
+.B shell\-backward\-kill\-word
+Kill the word behind point.
+Word boundaries are the same as those used by \fBshell\-backward\-word\fP.
+.TP
+.B unix\-word\-rubout (C\-w)
+Kill the word behind point, using white space as a word boundary.
+The killed text is saved on the kill-ring.
+.TP
+.B unix\-filename\-rubout
+Kill the word behind point, using white space and the slash character
+as the word boundaries.
+The killed text is saved on the kill-ring.
+.TP
+.B delete\-horizontal\-space (M\-\e)
+Delete all spaces and tabs around point.
+.TP
+.B kill\-region
+Kill the text in the current region.
+.TP
+.B copy\-region\-as\-kill
+Copy the text in the region to the kill buffer.
+.TP
+.B copy\-backward\-word
+Copy the word before point to the kill buffer.
+The word boundaries are the same as \fBbackward\-word\fP.
+.TP
+.B copy\-forward\-word
+Copy the word following point to the kill buffer.
+The word boundaries are the same as \fBforward\-word\fP.
+.TP
+.B yank (C\-y)
+Yank the top of the kill ring into the buffer at point.
+.TP
+.B yank\-pop (M\-y)
+Rotate the kill ring, and yank the new top. Only works following
+.B yank
+or
+.BR yank\-pop .
+.PD
+.SS Numeric Arguments
+.PP
+.PD 0
+.TP
+.B digit\-argument (M\-0, M\-1, ..., M\-\-)
+Add this digit to the argument already accumulating, or start a new
+argument. M\-\- starts a negative argument.
+.TP
+.B universal\-argument
+This is another way to specify an argument.
+If this command is followed by one or more digits, optionally with a
+leading minus sign, those digits define the argument.
+If the command is followed by digits, executing
+.B universal\-argument
+again ends the numeric argument, but is otherwise ignored.
+As a special case, if this command is immediately followed by a
+character that is neither a digit or minus sign, the argument count
+for the next command is multiplied by four.
+The argument count is initially one, so executing this function the
+first time makes the argument count four, a second time makes the
+argument count sixteen, and so on.
+.PD
+.SS Completing
+.PP
+.PD 0
+.TP
+.B complete (TAB)
+Attempt to perform completion on the text before point.
+.B Bash
+attempts completion treating the text as a variable (if the
+text begins with \fB$\fP), username (if the text begins with
+\fB~\fP), hostname (if the text begins with \fB@\fP), or
+command (including aliases and functions) in turn. If none
+of these produces a match, filename completion is attempted.
+.TP
+.B possible\-completions (M\-?)
+List the possible completions of the text before point.
+.TP
+.B insert\-completions (M\-*)
+Insert all completions of the text before point
+that would have been generated by
+\fBpossible\-completions\fP.
+.TP
+.B menu\-complete
+Similar to \fBcomplete\fP, but replaces the word to be completed
+with a single match from the list of possible completions.
+Repeated execution of \fBmenu\-complete\fP steps through the list
+of possible completions, inserting each match in turn.
+At the end of the list of completions, the bell is rung
+(subject to the setting of \fBbell\-style\fP)
+and the original text is restored.
+An argument of \fIn\fP moves \fIn\fP positions forward in the list
+of matches; a negative argument may be used to move backward
+through the list.
+This command is intended to be bound to \fBTAB\fP, but is unbound
+by default.
+.TP
+.B menu\-complete\-backward
+Identical to \fBmenu\-complete\fP, but moves backward through the list
+of possible completions, as if \fBmenu\-complete\fP had been given a
+negative argument. This command is unbound by default.
+.TP
+.B delete\-char\-or\-list
+Deletes the character under the cursor if not at the beginning or
+end of the line (like \fBdelete\-char\fP).
+If at the end of the line, behaves identically to
+\fBpossible\-completions\fP.
+This command is unbound by default.
+.TP
+.B complete\-filename (M\-/)
+Attempt filename completion on the text before point.
+.TP
+.B possible\-filename\-completions (C\-x /)
+List the possible completions of the text before point,
+treating it as a filename.
+.TP
+.B complete\-username (M\-~)
+Attempt completion on the text before point, treating
+it as a username.
+.TP
+.B possible\-username\-completions (C\-x ~)
+List the possible completions of the text before point,
+treating it as a username.
+.TP
+.B complete\-variable (M\-$)
+Attempt completion on the text before point, treating
+it as a shell variable.
+.TP
+.B possible\-variable\-completions (C\-x $)
+List the possible completions of the text before point,
+treating it as a shell variable.
+.TP
+.B complete\-hostname (M\-@)
+Attempt completion on the text before point, treating
+it as a hostname.
+.TP
+.B possible\-hostname\-completions (C\-x @)
+List the possible completions of the text before point,
+treating it as a hostname.
+.TP
+.B complete\-command (M\-!)
+Attempt completion on the text before point, treating
+it as a command name. Command completion attempts to
+match the text against aliases, reserved words, shell
+functions, shell builtins, and finally executable filenames,
+in that order.
+.TP
+.B possible\-command\-completions (C\-x !)
+List the possible completions of the text before point,
+treating it as a command name.
+.TP
+.B dynamic\-complete\-history (M\-TAB)
+Attempt completion on the text before point, comparing
+the text against lines from the history list for possible
+completion matches.
+.TP
+.B dabbrev\-expand
+Attempt menu completion on the text before point, comparing
+the text against lines from the history list for possible
+completion matches.
+.TP
+.B complete\-into\-braces (M\-{)
+Perform filename completion and insert the list of possible completions
+enclosed within braces so the list is available to the shell (see
+.B Brace Expansion
+above).
+.PD
+.SS Keyboard Macros
+.PP
+.PD 0
+.TP
+.B start\-kbd\-macro (C\-x (\^)
+Begin saving the characters typed into the current keyboard macro.
+.TP
+.B end\-kbd\-macro (C\-x )\^)
+Stop saving the characters typed into the current keyboard macro
+and store the definition.
+.TP
+.B call\-last\-kbd\-macro (C\-x e)
+Re-execute the last keyboard macro defined, by making the characters
+in the macro appear as if typed at the keyboard.
+.TP
+.B print\-last\-kbd\-macro ()
+Print the last keyboard macro defined in a format suitable for the
+\fIinputrc\fP file.
+.PD
+.SS Miscellaneous
+.PP
+.PD 0
+.TP
+.B re\-read\-init\-file (C\-x C\-r)
+Read in the contents of the \fIinputrc\fP file, and incorporate
+any bindings or variable assignments found there.
+.TP
+.B abort (C\-g)
+Abort the current editing command and
+ring the terminal's bell (subject to the setting of
+.BR bell\-style ).
+.TP
+.B do\-uppercase\-version (M\-a, M\-b, M\-\fIx\fP, ...)
+If the metafied character \fIx\fP is lowercase, run the command
+that is bound to the corresponding uppercase character.
+.TP
+.B prefix\-meta (ESC)
+Metafy the next character typed.
+.SM
+.B ESC
+.B f
+is equivalent to
+.BR Meta\-f .
+.TP
+.B undo (C\-_, C\-x C\-u)
+Incremental undo, separately remembered for each line.
+.TP
+.B revert\-line (M\-r)
+Undo all changes made to this line. This is like executing the
+.B undo
+command enough times to return the line to its initial state.
+.TP
+.B tilde\-expand (M\-&)
+Perform tilde expansion on the current word.
+.TP
+.B set\-mark (C\-@, M\-<space>)
+Set the mark to the point. If a
+numeric argument is supplied, the mark is set to that position.
+.TP
+.B exchange\-point\-and\-mark (C\-x C\-x)
+Swap the point with the mark. The current cursor position is set to
+the saved position, and the old cursor position is saved as the mark.
+.TP
+.B character\-search (C\-])
+A character is read and point is moved to the next occurrence of that
+character. A negative count searches for previous occurrences.
+.TP
+.B character\-search\-backward (M\-C\-])
+A character is read and point is moved to the previous occurrence of that
+character. A negative count searches for subsequent occurrences.
+.TP
+.B skip\-csi\-sequence
+Read enough characters to consume a multi-key sequence such as those
+defined for keys like Home and End. Such sequences begin with a
+Control Sequence Indicator (CSI), usually ESC\-[. If this sequence is
+bound to "\e[", keys producing such sequences will have no effect
+unless explicitly bound to a readline command, instead of inserting
+stray characters into the editing buffer. This is unbound by default,
+but usually bound to ESC\-[.
+.TP
+.B insert\-comment (M\-#)
+Without a numeric argument, the value of the readline
+.B comment\-begin
+variable is inserted at the beginning of the current line.
+If a numeric argument is supplied, this command acts as a toggle: if
+the characters at the beginning of the line do not match the value
+of \fBcomment\-begin\fP, the value is inserted, otherwise
+the characters in \fBcomment\-begin\fP are deleted from the beginning of
+the line.
+In either case, the line is accepted as if a newline had been typed.
+The default value of
+\fBcomment\-begin\fP causes this command to make the current line
+a shell comment.
+If a numeric argument causes the comment character to be removed, the line
+will be executed by the shell.
+.TP
+.B glob\-complete\-word (M\-g)
+The word before point is treated as a pattern for pathname expansion,
+with an asterisk implicitly appended. This pattern is used to
+generate a list of matching filenames for possible completions.
+.TP
+.B glob\-expand\-word (C\-x *)
+The word before point is treated as a pattern for pathname expansion,
+and the list of matching filenames is inserted, replacing the word.
+If a numeric argument is supplied, an asterisk is appended before
+pathname expansion.
+.TP
+.B glob\-list\-expansions (C\-x g)
+The list of expansions that would have been generated by
+.B glob\-expand\-word
+is displayed, and the line is redrawn.
+If a numeric argument is supplied, an asterisk is appended before
+pathname expansion.
+.TP
+.B dump\-functions
+Print all of the functions and their key bindings to the
+readline output stream. If a numeric argument is supplied,
+the output is formatted in such a way that it can be made part
+of an \fIinputrc\fP file.
+.TP
+.B dump\-variables
+Print all of the settable readline variables and their values to the
+readline output stream. If a numeric argument is supplied,
+the output is formatted in such a way that it can be made part
+of an \fIinputrc\fP file.
+.TP
+.B dump\-macros
+Print all of the readline key sequences bound to macros and the
+strings they output. If a numeric argument is supplied,
+the output is formatted in such a way that it can be made part
+of an \fIinputrc\fP file.
+.TP
+.B display\-shell\-version (C\-x C\-v)
+Display version information about the current instance of
+.BR bash .
+.PD
+.SS Programmable Completion
+.PP
+When word completion is attempted for an argument to a command for
+which a completion specification (a \fIcompspec\fP) has been defined
+using the \fBcomplete\fP builtin (see
+.SM
+.B "SHELL BUILTIN COMMANDS"
+below), the programmable completion facilities are invoked.
+.PP
+First, the command name is identified.
+If the command word is the empty string (completion attempted at the
+beginning of an empty line), any compspec defined with
+the \fB\-E\fP option to \fBcomplete\fP is used.
+If a compspec has been defined for that command, the
+compspec is used to generate the list of possible completions for the word.
+If the command word is a full pathname, a compspec for the full
+pathname is searched for first.
+If no compspec is found for the full pathname, an attempt is made to
+find a compspec for the portion following the final slash.
+If those searches do not result in a compspec, any compspec defined with
+the \fB\-D\fP option to \fBcomplete\fP is used as the default.
+.PP
+Once a compspec has been found, it is used to generate the list of
+matching words.
+If a compspec is not found, the default \fBbash\fP completion as
+described above under \fBCompleting\fP is performed.
+.PP
+First, the actions specified by the compspec are used.
+Only matches which are prefixed by the word being completed are
+returned.
+When the
+.B \-f
+or
+.B \-d
+option is used for filename or directory name completion, the shell
+variable
+.SM
+.B FIGNORE
+is used to filter the matches.
+.PP
+Any completions specified by a pathname expansion pattern to the
+\fB\-G\fP option are generated next.
+The words generated by the pattern need not match the word
+being completed.
+The
+.SM
+.B GLOBIGNORE
+shell variable is not used to filter the matches, but the
+.SM
+.B FIGNORE
+variable is used.
+.PP
+Next, the string specified as the argument to the \fB\-W\fP option
+is considered.
+The string is first split using the characters in the
+.SM
+.B IFS
+special variable as delimiters.
+Shell quoting is honored.
+Each word is then expanded using
+brace expansion, tilde expansion, parameter and variable expansion,
+command substitution, and arithmetic expansion,
+as described above under
+.SM
+.BR EXPANSION .
+The results are split using the rules described above under
+\fBWord Splitting\fP.
+The results of the expansion are prefix-matched against the word being
+completed, and the matching words become the possible completions.
+.PP
+After these matches have been generated, any shell function or command
+specified with the \fB\-F\fP and \fB\-C\fP options is invoked.
+When the command or function is invoked, the
+.SM
+.BR COMP_LINE ,
+.SM
+.BR COMP_POINT ,
+.SM
+.BR COMP_KEY ,
+and
+.SM
+.B COMP_TYPE
+variables are assigned values as described above under
+\fBShell Variables\fP.
+If a shell function is being invoked, the
+.SM
+.B COMP_WORDS
+and
+.SM
+.B COMP_CWORD
+variables are also set.
+When the function or command is invoked,
+the first argument (\fB$1\fP) is the name of the command whose arguments are
+being completed,
+the second argument (\fB$2\fP) is the word being completed,
+and the third argument (\fB$3\fP) is the word preceding the word being
+completed on the current command line.
+No filtering of the generated completions against the word being completed
+is performed; the function or command has complete freedom in generating
+the matches.
+.PP
+Any function specified with \fB\-F\fP is invoked first.
+The function may use any of the shell facilities, including the
+\fBcompgen\fP builtin described below, to generate the matches.
+It must put the possible completions in the
+.SM
+.B COMPREPLY
+array variable, one per array element.
+.PP
+Next, any command specified with the \fB\-C\fP option is invoked
+in an environment equivalent to command substitution.
+It should print a list of completions, one per line, to the
+standard output.
+Backslash may be used to escape a newline, if necessary.
+.PP
+After all of the possible completions are generated, any filter
+specified with the \fB\-X\fP option is applied to the list.
+The filter is a pattern as used for pathname expansion; a \fB&\fP
+in the pattern is replaced with the text of the word being completed.
+A literal \fB&\fP may be escaped with a backslash; the backslash
+is removed before attempting a match.
+Any completion that matches the pattern will be removed from the list.
+A leading \fB!\fP negates the pattern; in this case any completion
+not matching the pattern will be removed.
+If the
+.B nocasematch
+shell option is enabled, the match is performed without regard to the case
+of alphabetic characters.
+.PP
+Finally, any prefix and suffix specified with the \fB\-P\fP and \fB\-S\fP
+options are added to each member of the completion list, and the result is
+returned to the readline completion code as the list of possible
+completions.
+.PP
+If the previously-applied actions do not generate any matches, and the
+\fB\-o dirnames\fP option was supplied to \fBcomplete\fP when the
+compspec was defined, directory name completion is attempted.
+.PP
+If the \fB\-o plusdirs\fP option was supplied to \fBcomplete\fP when the
+compspec was defined, directory name completion is attempted and any
+matches are added to the results of the other actions.
+.PP
+By default, if a compspec is found, whatever it generates is returned
+to the completion code as the full set of possible completions.
+The default \fBbash\fP completions are not attempted, and the readline
+default of filename completion is disabled.
+If the \fB\-o bashdefault\fP option was supplied to \fBcomplete\fP when
+the compspec was defined, the \fBbash\fP default completions are attempted
+if the compspec generates no matches.
+If the \fB\-o default\fP option was supplied to \fBcomplete\fP when the
+compspec was defined, readline's default completion will be performed
+if the compspec (and, if attempted, the default \fBbash\fP completions)
+generate no matches.
+.PP
+When a compspec indicates that directory name completion is desired,
+the programmable completion functions force readline to append a slash
+to completed names which are symbolic links to directories, subject to
+the value of the \fBmark\-directories\fP readline variable, regardless
+of the setting of the \fBmark-symlinked\-directories\fP readline variable.
+.PP
+There is some support for dynamically modifying completions. This is
+most useful when used in combination with a default completion specified
+with \fBcomplete -D\fP.
+It's possible for shell functions executed as completion
+handlers to indicate that completion should be retried by returning an
+exit status of 124. If a shell function returns 124, and changes
+the compspec associated with the command on which completion is being
+attempted (supplied as the first argument when the function is executed),
+programmable completion restarts from the beginning, with an
+attempt to find a new compspec for that command. This allows a set of
+completions to be built dynamically as completion is attempted, rather than
+being loaded all at once.
+.PP
+For instance, assuming that there is a library of compspecs, each kept in a
+file corresponding to the name of the command, the following default
+completion function would load completions dynamically:
+.PP
+\f(CW_completion_loader()
+.br
+{
+.br
+ . "/etc/bash_completion.d/$1.sh" >/dev/null 2>&1 && return 124
+.br
+}
+.br
+complete -D -F _completion_loader -o bashdefault -o default
+.br
+\fP
+.SH HISTORY
+When the
+.B \-o history
+option to the
+.B set
+builtin is enabled, the shell provides access to the
+\fIcommand history\fP,
+the list of commands previously typed.
+The value of the
+.SM
+.B HISTSIZE
+variable is used as the
+number of commands to save in a history list.
+The text of the last
+.SM
+.B HISTSIZE
+commands (default 500) is saved. The shell
+stores each command in the history list prior to parameter and
+variable expansion (see
+.SM
+.B EXPANSION
+above) but after history expansion is performed, subject to the
+values of the shell variables
+.SM
+.B HISTIGNORE
+and
+.SM
+.BR HISTCONTROL .
+.PP
+On startup, the history is initialized from the file named by
+the variable
+.SM
+.B HISTFILE
+(default \fI~/.bash_history\fP).
+The file named by the value of
+.SM
+.B HISTFILE
+is truncated, if necessary, to contain no more than
+the number of lines specified by the value of
+.SM
+.BR HISTFILESIZE .
+If \fBHISTFILESIZE\fP is unset, or set to null, a non-numeric value,
+or a numeric value less than zero, the history file is not truncated.
+When the history file is read,
+lines beginning with the history comment character followed immediately
+by a digit are interpreted as timestamps for the preceding history line.
+These timestamps are optionally displayed depending on the value of the
+.SM
+.B HISTTIMEFORMAT
+variable.
+When a shell with history enabled exits, the last
+.SM
+.B $HISTSIZE
+lines are copied from the history list to
+.SM
+.BR $HISTFILE .
+If the
+.B histappend
+shell option is enabled
+(see the description of
+.B shopt
+under
+.SM
+.B "SHELL BUILTIN COMMANDS"
+below), the lines are appended to the history file,
+otherwise the history file is overwritten.
+If
+.SM
+.B HISTFILE
+is unset, or if the history file is unwritable, the history is
+not saved.
+If the
+.SM
+.B HISTTIMEFORMAT
+variable is set, time stamps are written to the history file, marked
+with the history comment character, so
+they may be preserved across shell sessions.
+This uses the history comment character to distinguish timestamps from
+other history lines.
+After saving the history, the history file is truncated
+to contain no more than
+.SM
+.B HISTFILESIZE
+lines. If
+.SM
+.B HISTFILESIZE
+is unset, or set to null, a non-numeric value,
+or a numeric value less than zero, the history file is not truncated.
+.PP
+The builtin command
+.B fc
+(see
+.SM
+.B SHELL BUILTIN COMMANDS
+below) may be used to list or edit and re-execute a portion of
+the history list.
+The
+.B history
+builtin may be used to display or modify the history list and
+manipulate the history file.
+When using command-line editing, search commands
+are available in each editing mode that provide access to the
+history list.
+.PP
+The shell allows control over which commands are saved on the history
+list. The
+.SM
+.B HISTCONTROL
+and
+.SM
+.B HISTIGNORE
+variables may be set to cause the shell to save only a subset of the
+commands entered.
+The
+.B cmdhist
+shell option, if enabled, causes the shell to attempt to save each
+line of a multi-line command in the same history entry, adding
+semicolons where necessary to preserve syntactic correctness.
+The
+.B lithist
+shell option causes the shell to save the command with embedded newlines
+instead of semicolons. See the description of the
+.B shopt
+builtin below under
+.SM
+.B "SHELL BUILTIN COMMANDS"
+for information on setting and unsetting shell options.
+.SH "HISTORY EXPANSION"
+.PP
+The shell supports a history expansion feature that
+is similar to the history expansion in
+.BR csh.
+This section describes what syntax features are available. This
+feature is enabled by default for interactive shells, and can be
+disabled using the
+.B +H
+option to the
+.B set
+builtin command (see
+.SM
+.B SHELL BUILTIN COMMANDS
+below). Non-interactive shells do not perform history expansion
+by default.
+.PP
+History expansions introduce words from the history list into
+the input stream, making it easy to repeat commands, insert the
+arguments to a previous command into the current input line, or
+fix errors in previous commands quickly.
+.PP
+History expansion is performed immediately after a complete line
+is read, before the shell breaks it into words.
+It takes place in two parts.
+The first is to determine which line from the history list
+to use during substitution.
+The second is to select portions of that line for inclusion into
+the current one.
+The line selected from the history is the \fIevent\fP,
+and the portions of that line that are acted upon are \fIwords\fP.
+Various \fImodifiers\fP are available to manipulate the selected words.
+The line is broken into words in the same fashion as when reading input,
+so that several \fImetacharacter\fP-separated words surrounded by
+quotes are considered one word.
+History expansions are introduced by the appearance of the
+history expansion character, which is \^\fB!\fP\^ by default.
+Only backslash (\^\fB\e\fP\^) and single quotes can quote
+the history expansion character.
+.PP
+Several characters inhibit history expansion if found immediately
+following the history expansion character, even if it is unquoted:
+space, tab, newline, carriage return, and \fB=\fP.
+If the \fBextglob\fP shell option is enabled, \fB(\fP will also
+inhibit expansion.
+.PP
+Several shell options settable with the
+.B shopt
+builtin may be used to tailor the behavior of history expansion.
+If the
+.B histverify
+shell option is enabled (see the description of the
+.B shopt
+builtin below), and
+.B readline
+is being used, history substitutions are not immediately passed to
+the shell parser.
+Instead, the expanded line is reloaded into the
+.B readline
+editing buffer for further modification.
+If
+.B readline
+is being used, and the
+.B histreedit
+shell option is enabled, a failed history substitution will be reloaded
+into the
+.B readline
+editing buffer for correction.
+The
+.B \-p
+option to the
+.B history
+builtin command may be used to see what a history expansion will
+do before using it.
+The
+.B \-s
+option to the
+.B history
+builtin may be used to add commands to the end of the history list
+without actually executing them, so that they are available for
+subsequent recall.
+.PP
+The shell allows control of the various characters used by the
+history expansion mechanism (see the description of
+.B histchars
+above under
+.BR "Shell Variables" ).
+The shell uses
+the history comment character to mark history timestamps when
+writing the history file.
+.SS Event Designators
+.PP
+An event designator is a reference to a command line entry in the
+history list.
+Unless the reference is absolute, events are relative to the current
+position in the history list.
+.PP
+.PD 0
+.TP
+.B !
+Start a history substitution, except when followed by a
+.BR blank ,
+newline, carriage return, =
+or ( (when the \fBextglob\fP shell option is enabled using
+the \fBshopt\fP builtin).
+.TP
+.B !\fIn\fR
+Refer to command line
+.IR n .
+.TP
+.B !\-\fIn\fR
+Refer to the current command minus
+.IR n .
+.TP
+.B !!
+Refer to the previous command. This is a synonym for `!\-1'.
+.TP
+.B !\fIstring\fR
+Refer to the most recent command preceding the current position in the
+history list starting with
+.IR string .
+.TP
+.B !?\fIstring\fR\fB[?]\fR
+Refer to the most recent command preceding the current position in the
+history list containing
+.IR string .
+The trailing \fB?\fP may be omitted if
+.I string
+is followed immediately by a newline.
+.TP
+.B \d\s+2^\s-2\u\fIstring1\fP\d\s+2^\s-2\u\fIstring2\fP\d\s+2^\s-2\u
+Quick substitution. Repeat the previous command, replacing
+.I string1
+with
+.IR string2 .
+Equivalent to
+``!!:s/\fIstring1\fP/\fIstring2\fP/''
+(see \fBModifiers\fP below).
+.TP
+.B !#
+The entire command line typed so far.
+.PD
+.SS Word Designators
+.PP
+Word designators are used to select desired words from the event.
+A
+.B :
+separates the event specification from the word designator.
+It may be omitted if the word designator begins with a
+.BR ^ ,
+.BR $ ,
+.BR * ,
+.BR \- ,
+or
+.BR % .
+Words are numbered from the beginning of the line,
+with the first word being denoted by 0 (zero).
+Words are inserted into the current line separated by single spaces.
+.PP
+.PD 0
+.TP
+.B 0 (zero)
+The zeroth word. For the shell, this is the command
+word.
+.TP
+.I n
+The \fIn\fRth word.
+.TP
+.B ^
+The first argument. That is, word 1.
+.TP
+.B $
+The last word. This is usually the last argument, but will expand to the
+zeroth word if there is only one word in the line.
+.TP
+.B %
+The word matched by the most recent `?\fIstring\fR?' search.
+.TP
+.I x\fB\-\fPy
+A range of words; `\-\fIy\fR' abbreviates `0\-\fIy\fR'.
+.TP
+.B *
+All of the words but the zeroth. This is a synonym
+for `\fI1\-$\fP'. It is not an error to use
+.B *
+if there is just one
+word in the event; the empty string is returned in that case.
+.TP
+.B x*
+Abbreviates \fIx\-$\fP.
+.TP
+.B x\-
+Abbreviates \fIx\-$\fP like \fBx*\fP, but omits the last word.
+.PD
+.PP
+If a word designator is supplied without an event specification, the
+previous command is used as the event.
+.SS Modifiers
+.PP
+After the optional word designator, there may appear a sequence of
+one or more of the following modifiers, each preceded by a `:'.
+.PP
+.PD 0
+.PP
+.TP
+.B h
+Remove a trailing filename component, leaving only the head.
+.TP
+.B t
+Remove all leading filename components, leaving the tail.
+.TP
+.B r
+Remove a trailing suffix of the form \fI.xxx\fP, leaving the
+basename.
+.TP
+.B e
+Remove all but the trailing suffix.
+.TP
+.B p
+Print the new command but do not execute it.
+.TP
+.B q
+Quote the substituted words, escaping further substitutions.
+.TP
+.B x
+Quote the substituted words as with
+.BR q ,
+but break into words at
+.B blanks
+and newlines.
+.TP
+.B s/\fIold\fP/\fInew\fP/
+Substitute
+.I new
+for the first occurrence of
+.I old
+in the event line. Any delimiter can be used in place of /. The
+final delimiter is optional if it is the last character of the
+event line. The delimiter may be quoted in
+.I old
+and
+.I new
+with a single backslash. If & appears in
+.IR new ,
+it is replaced by
+.IR old .
+A single backslash will quote the &. If
+.I old
+is null, it is set to the last
+.I old
+substituted, or, if no previous history substitutions took place,
+the last
+.I string
+in a
+.B !?\fIstring\fR\fB[?]\fR
+search.
+.TP
+.B &
+Repeat the previous substitution.
+.TP
+.B g
+Cause changes to be applied over the entire event line. This is
+used in conjunction with `\fB:s\fP' (e.g., `\fB:gs/\fIold\fP/\fInew\fP/\fR')
+or `\fB:&\fP'. If used with
+`\fB:s\fP', any delimiter can be used
+in place of /, and the final delimiter is optional
+if it is the last character of the event line.
+An \fBa\fP may be used as a synonym for \fBg\fP.
+.TP
+.B G
+Apply the following `\fBs\fP' modifier once to each word in the event line.
+.PD
+.SH "SHELL BUILTIN COMMANDS"
+.\" start of bash_builtins
+.zZ
+.PP
+Unless otherwise noted, each builtin command documented in this
+section as accepting options preceded by
+.B \-
+accepts
+.B \-\-
+to signify the end of the options.
+The \fB:\fP, \fBtrue\fP, \fBfalse\fP, and \fBtest\fP builtins
+do not accept options and do not treat \fB\-\-\fP specially.
+The \fBexit\fP, \fBlogout\fP, \fBbreak\fP, \fBcontinue\fP, \fBlet\fP,
+and \fBshift\fP builtins accept and process arguments beginning with
+\fB\-\fP without requiring \fB\-\-\fP.
+Other builtins that accept arguments but are not specified as accepting
+options interpret arguments beginning with \fB\-\fP as invalid options and
+require \fB\-\-\fP to prevent this interpretation.
+.sp .5
+.PD 0
+.TP
+\fB:\fP [\fIarguments\fP]
+.PD
+No effect; the command does nothing beyond expanding
+.I arguments
+and performing any specified
+redirections. A zero exit code is returned.
+.TP
+\fB .\| \fP \fIfilename\fP [\fIarguments\fP]
+.PD 0
+.TP
+\fBsource\fP \fIfilename\fP [\fIarguments\fP]
+.PD
+Read and execute commands from
+.I filename
+in the current
+shell environment and return the exit status of the last command
+executed from
+.IR filename .
+If
+.I filename
+does not contain a slash, filenames in
+.SM
+.B PATH
+are used to find the directory containing
+.IR filename .
+The file searched for in
+.SM
+.B PATH
+need not be executable.
+When \fBbash\fP is not in \fIposix mode\fP, the current directory is
+searched if no file is found in
+.SM
+.BR PATH .
+If the
+.B sourcepath
+option to the
+.B shopt
+builtin command is turned off, the
+.SM
+.B PATH
+is not searched.
+If any \fIarguments\fP are supplied, they become the positional
+parameters when \fIfilename\fP is executed. Otherwise the positional
+parameters are unchanged.
+The return status is the status of the last command exited within
+the script (0 if no commands are executed), and false if
+.I filename
+is not found or cannot be read.
+.TP
+\fBalias\fP [\fB\-p\fP] [\fIname\fP[=\fIvalue\fP] ...]
+\fBAlias\fP with no arguments or with the
+.B \-p
+option prints the list of aliases in the form
+\fBalias\fP \fIname\fP=\fIvalue\fP on standard output.
+When arguments are supplied, an alias is defined for
+each \fIname\fP whose \fIvalue\fP is given.
+A trailing space in \fIvalue\fP causes the next word to be
+checked for alias substitution when the alias is expanded.
+For each \fIname\fP in the argument list for which no \fIvalue\fP
+is supplied, the name and value of the alias is printed.
+\fBAlias\fP returns true unless a \fIname\fP is given for which
+no alias has been defined.
+.TP
+\fBbg\fP [\fIjobspec\fP ...]
+Resume each suspended job \fIjobspec\fP in the background, as if it
+had been started with
+.BR & .
+If
+.I jobspec
+is not present, the shell's notion of the \fIcurrent job\fP is used.
+.B bg
+.I jobspec
+returns 0 unless run when job control is disabled or, when run with
+job control enabled, any specified \fIjobspec\fP was not found
+or was started without job control.
+.TP
+\fBbind\fP [\fB\-m\fP \fIkeymap\fP] [\fB\-lpsvPSVX\fP]
+.PD 0
+.TP
+\fBbind\fP [\fB\-m\fP \fIkeymap\fP] [\fB\-q\fP \fIfunction\fP] [\fB\-u\fP \fIfunction\fP] [\fB\-r\fP \fIkeyseq\fP]
+.TP
+\fBbind\fP [\fB\-m\fP \fIkeymap\fP] \fB\-f\fP \fIfilename\fP
+.TP
+\fBbind\fP [\fB\-m\fP \fIkeymap\fP] \fB\-x\fP \fIkeyseq\fP:\fIshell\-command\fP
+.TP
+\fBbind\fP [\fB\-m\fP \fIkeymap\fP] \fIkeyseq\fP:\fIfunction\-name\fP
+.TP
+\fBbind\fP [\fB\-m\fP \fIkeymap\fP] \fIkeyseq\fP:\fIreadline\-command\fP
+.PD
+Display current
+.B readline
+key and function bindings, bind a key sequence to a
+.B readline
+function or macro, or set a
+.B readline
+variable.
+Each non-option argument is a command as it would appear in
+.IR .inputrc ,
+but each binding or command must be passed as a separate argument;
+e.g., '"\eC\-x\eC\-r": re\-read\-init\-file'.
+Options, if supplied, have the following meanings:
+.RS
+.PD 0
+.TP
+.B \-m \fIkeymap\fP
+Use
+.I keymap
+as the keymap to be affected by the subsequent bindings.
+Acceptable
+.I keymap
+names are
+\fIemacs, emacs\-standard, emacs\-meta, emacs\-ctlx, vi,
+vi\-move, vi\-command\fP, and
+.IR vi\-insert .
+\fIvi\fP is equivalent to \fIvi\-command\fP; \fIemacs\fP is
+equivalent to \fIemacs\-standard\fP.
+.TP
+.B \-l
+List the names of all \fBreadline\fP functions.
+.TP
+.B \-p
+Display \fBreadline\fP function names and bindings in such a way
+that they can be re-read.
+.TP
+.B \-P
+List current \fBreadline\fP function names and bindings.
+.TP
+.B \-s
+Display \fBreadline\fP key sequences bound to macros and the strings
+they output in such a way that they can be re-read.
+.TP
+.B \-S
+Display \fBreadline\fP key sequences bound to macros and the strings
+they output.
+.TP
+.B \-v
+Display \fBreadline\fP variable names and values in such a way that they
+can be re-read.
+.TP
+.B \-V
+List current \fBreadline\fP variable names and values.
+.TP
+.B \-f \fIfilename\fP
+Read key bindings from \fIfilename\fP.
+.TP
+.B \-q \fIfunction\fP
+Query about which keys invoke the named \fIfunction\fP.
+.TP
+.B \-u \fIfunction\fP
+Unbind all keys bound to the named \fIfunction\fP.
+.TP
+.B \-r \fIkeyseq\fP
+Remove any current binding for \fIkeyseq\fP.
+.TP
+.B \-x \fIkeyseq\fP:\fIshell\-command\fP
+Cause \fIshell\-command\fP to be executed whenever \fIkeyseq\fP is
+entered.
+When \fIshell\-command\fP is executed, the shell sets the
+.SM
+.B READLINE_LINE
+variable to the contents of the \fBreadline\fP line buffer and the
+.SM
+.B READLINE_POINT
+variable to the current location of the insertion point.
+If the executed command changes the value of
+.SM
+.B READLINE_LINE
+or
+.SM
+.BR READLINE_POINT ,
+those new values will be reflected in the editing state.
+.TP
+.B \-X
+List all key sequences bound to shell commands and the associated commands
+in a format that can be reused as input.
+.PD
+.PP
+The return value is 0 unless an unrecognized option is given or an
+error occurred.
+.RE
+.TP
+\fBbreak\fP [\fIn\fP]
+Exit from within a
+.BR for ,
+.BR while ,
+.BR until ,
+or
+.B select
+loop. If \fIn\fP is specified, break \fIn\fP levels.
+.I n
+must be \(>= 1. If
+.I n
+is greater than the number of enclosing loops, all enclosing loops
+are exited.
+The return value is 0 unless \fIn\fP is not greater than or equal to 1.
+.TP
+\fBbuiltin\fP \fIshell\-builtin\fP [\fIarguments\fP]
+Execute the specified shell builtin, passing it
+.IR arguments ,
+and return its exit status.
+This is useful when defining a
+function whose name is the same as a shell builtin,
+retaining the functionality of the builtin within the function.
+The \fBcd\fP builtin is commonly redefined this way.
+The return status is false if
+.I shell\-builtin
+is not a shell builtin command.
+.TP
+\fBcaller\fP [\fIexpr\fP]
+Returns the context of any active subroutine call (a shell function or
+a script executed with the \fB.\fP or \fBsource\fP builtins).
+Without \fIexpr\fP, \fBcaller\fP displays the line number and source
+filename of the current subroutine call.
+If a non-negative integer is supplied as \fIexpr\fP, \fBcaller\fP
+displays the line number, subroutine name, and source file corresponding
+to that position in the current execution call stack. This extra
+information may be used, for example, to print a stack trace. The
+current frame is frame 0.
+The return value is 0 unless the shell is not executing a subroutine
+call or \fIexpr\fP does not correspond to a valid position in the
+call stack.
+.TP
+\fBcd\fP [\fB\-L\fP|[\fB\-P\fP [\fB\-e\fP]] [\-@]] [\fIdir\fP]
+Change the current directory to \fIdir\fP.
+if \fIdir\fP is not supplied, the value of the
+.SM
+.B HOME
+shell variable is the default.
+Any additional arguments following \fIdir\fP are ignored.
+The variable
+.SM
+.B CDPATH
+defines the search path for the directory containing
+.IR dir :
+each directory name in
+.SM
+.B CDPATH
+is searched for \fIdir\fP.
+Alternative directory names in
+.SM
+.B CDPATH
+are separated by a colon (:). A null directory name in
+.SM
+.B CDPATH
+is the same as the current directory, i.e., ``\fB.\fP''. If
+.I dir
+begins with a slash (/),
+then
+.SM
+.B CDPATH
+is not used. The
+.B \-P
+option causes \fBcd\fP to use the physical directory structure
+by resolving symbolic links while traversing \fIdir\fP and
+before processing instances of \fI..\fP in \fIdir\fP (see also the
+.B \-P
+option to the
+.B set
+builtin command); the
+.B \-L
+option forces symbolic links to be followed by resolving the link
+after processing instances of \fI..\fP in \fIdir\fP.
+If \fI..\fP appears in \fIdir\fP, it is processed by removing the
+immediately previous pathname component from \fIdir\fP, back to a slash
+or the beginning of \fIdir\fP.
+If the
+.B \-e
+option is supplied with
+.BR \-P ,
+and the current working directory cannot be successfully determined
+after a successful directory change, \fBcd\fP will return an unsuccessful
+status.
+On systems that support it, the \fB\-@\fP option presents the extended
+attributes associated with a file as a directory.
+An argument of
+.B \-
+is converted to
+.SM
+.B $OLDPWD
+before the directory change is attempted.
+If a non-empty directory name from
+.SM
+.B CDPATH
+is used, or if
+\fB\-\fP is the first argument, and the directory change is
+successful, the absolute pathname of the new working directory is
+written to the standard output.
+The return value is true if the directory was successfully changed;
+false otherwise.
+.TP
+\fBcommand\fP [\fB\-pVv\fP] \fIcommand\fP [\fIarg\fP ...]
+Run
+.I command
+with
+.I args
+suppressing the normal shell function lookup.
+Only builtin commands or commands found in the
+.SM
+.B PATH
+are executed. If the
+.B \-p
+option is given, the search for
+.I command
+is performed using a default value for
+.SM
+.B PATH
+that is guaranteed to find all of the standard utilities.
+If either the
+.B \-V
+or
+.B \-v
+option is supplied, a description of
+.I command
+is printed. The
+.B \-v
+option causes a single word indicating the command or filename
+used to invoke
+.I command
+to be displayed; the
+.B \-V
+option produces a more verbose description.
+If the
+.B \-V
+or
+.B \-v
+option is supplied, the exit status is 0 if
+.I command
+was found, and 1 if not. If neither option is supplied and
+an error occurred or
+.I command
+cannot be found, the exit status is 127. Otherwise, the exit status of the
+.B command
+builtin is the exit status of
+.IR command .
+.TP
+\fBcompgen\fP [\fIoption\fP] [\fIword\fP]
+Generate possible completion matches for \fIword\fP according to
+the \fIoption\fPs, which may be any option accepted by the
+.B complete
+builtin with the exception of \fB\-p\fP and \fB\-r\fP, and write
+the matches to the standard output.
+When using the \fB\-F\fP or \fB\-C\fP options, the various shell variables
+set by the programmable completion facilities, while available, will not
+have useful values.
+.sp 1
+The matches will be generated in the same way as if the programmable
+completion code had generated them directly from a completion specification
+with the same flags.
+If \fIword\fP is specified, only those completions matching \fIword\fP
+will be displayed.
+.sp 1
+The return value is true unless an invalid option is supplied, or no
+matches were generated.
+.TP
+\fBcomplete\fP [\fB\-abcdefgjksuv\fP] [\fB\-o\fP \fIcomp-option\fP] [\fB\-DE\fP] [\fB\-A\fP \fIaction\fP] [\fB\-G\fP \fIglobpat\fP] [\fB\-W\fP \fIwordlist\fP] [\fB\-F\fP \fIfunction\fP] [\fB\-C\fP \fIcommand\fP]
+.br
+[\fB\-X\fP \fIfilterpat\fP] [\fB\-P\fP \fIprefix\fP] [\fB\-S\fP \fIsuffix\fP] \fIname\fP [\fIname ...\fP]
+.PD 0
+.TP
+\fBcomplete\fP \fB\-pr\fP [\fB\-DE\fP] [\fIname\fP ...]
+.PD
+Specify how arguments to each \fIname\fP should be completed.
+If the \fB\-p\fP option is supplied, or if no options are supplied,
+existing completion specifications are printed in a way that allows
+them to be reused as input.
+The \fB\-r\fP option removes a completion specification for
+each \fIname\fP, or, if no \fIname\fPs are supplied, all
+completion specifications.
+The \fB\-D\fP option indicates that the remaining options and actions should
+apply to the ``default'' command completion; that is, completion attempted
+on a command for which no completion has previously been defined.
+The \fB\-E\fP option indicates that the remaining options and actions should
+apply to ``empty'' command completion; that is, completion attempted on a
+blank line.
+.sp 1
+The process of applying these completion specifications when word completion
+is attempted is described above under \fBProgrammable Completion\fP.
+.sp 1
+Other options, if specified, have the following meanings.
+The arguments to the \fB\-G\fP, \fB\-W\fP, and \fB\-X\fP options
+(and, if necessary, the \fB\-P\fP and \fB\-S\fP options)
+should be quoted to protect them from expansion before the
+.B complete
+builtin is invoked.
+.RS
+.PD 0
+.TP 8
+\fB\-o\fP \fIcomp-option\fP
+The \fIcomp-option\fP controls several aspects of the compspec's behavior
+beyond the simple generation of completions.
+\fIcomp-option\fP may be one of:
+.RS
+.TP 8
+.B bashdefault
+Perform the rest of the default \fBbash\fP completions if the compspec
+generates no matches.
+.TP 8
+.B default
+Use readline's default filename completion if the compspec generates
+no matches.
+.TP 8
+.B dirnames
+Perform directory name completion if the compspec generates no matches.
+.TP 8
+.B filenames
+Tell readline that the compspec generates filenames, so it can perform any
+filename\-specific processing (like adding a slash to directory names,
+quoting special characters, or suppressing trailing spaces).
+Intended to be used with shell functions.
+.TP 8
+.B noquote
+Tell readline not to quote the completed words if they are filenames
+(quoting filenames is the default).
+.TP 8
+.B nospace
+Tell readline not to append a space (the default) to words completed at
+the end of the line.
+.TP 8
+.B plusdirs
+After any matches defined by the compspec are generated,
+directory name completion is attempted and any
+matches are added to the results of the other actions.
+.RE
+.TP 8
+\fB\-A\fP \fIaction\fP
+The \fIaction\fP may be one of the following to generate a list of possible
+completions:
+.RS
+.TP 8
+.B alias
+Alias names. May also be specified as \fB\-a\fP.
+.TP 8
+.B arrayvar
+Array variable names.
+.TP 8
+.B binding
+\fBReadline\fP key binding names.
+.TP 8
+.B builtin
+Names of shell builtin commands. May also be specified as \fB\-b\fP.
+.TP 8
+.B command
+Command names. May also be specified as \fB\-c\fP.
+.TP 8
+.B directory
+Directory names. May also be specified as \fB\-d\fP.
+.TP 8
+.B disabled
+Names of disabled shell builtins.
+.TP 8
+.B enabled
+Names of enabled shell builtins.
+.TP 8
+.B export
+Names of exported shell variables. May also be specified as \fB\-e\fP.
+.TP 8
+.B file
+File names. May also be specified as \fB\-f\fP.
+.TP 8
+.B function
+Names of shell functions.
+.TP 8
+.B group
+Group names. May also be specified as \fB\-g\fP.
+.TP 8
+.B helptopic
+Help topics as accepted by the \fBhelp\fP builtin.
+.TP 8
+.B hostname
+Hostnames, as taken from the file specified by the
+.SM
+.B HOSTFILE
+shell variable.
+.TP 8
+.B job
+Job names, if job control is active. May also be specified as \fB\-j\fP.
+.TP 8
+.B keyword
+Shell reserved words. May also be specified as \fB\-k\fP.
+.TP 8
+.B running
+Names of running jobs, if job control is active.
+.TP 8
+.B service
+Service names. May also be specified as \fB\-s\fP.
+.TP 8
+.B setopt
+Valid arguments for the \fB\-o\fP option to the \fBset\fP builtin.
+.TP 8
+.B shopt
+Shell option names as accepted by the \fBshopt\fP builtin.
+.TP 8
+.B signal
+Signal names.
+.TP 8
+.B stopped
+Names of stopped jobs, if job control is active.
+.TP 8
+.B user
+User names. May also be specified as \fB\-u\fP.
+.TP 8
+.B variable
+Names of all shell variables. May also be specified as \fB\-v\fP.
+.RE
+.TP 8
+\fB\-C\fP \fIcommand\fP
+\fIcommand\fP is executed in a subshell environment, and its output is
+used as the possible completions.
+.TP 8
+\fB\-F\fP \fIfunction\fP
+The shell function \fIfunction\fP is executed in the current shell
+environment.
+When the function is executed,
+the first argument (\fB$1\fP) is the name of the command whose arguments are
+being completed,
+the second argument (\fB$2\fP) is the word being completed,
+and the third argument (\fB$3\fP) is the word preceding the word being
+completed on the current command line.
+When it finishes, the possible completions are retrieved from the value
+of the
+.SM
+.B COMPREPLY
+array variable.
+.TP 8
+\fB\-G\fP \fIglobpat\fP
+The pathname expansion pattern \fIglobpat\fP is expanded to generate
+the possible completions.
+.TP 8
+\fB\-P\fP \fIprefix\fP
+\fIprefix\fP is added at the beginning of each possible completion
+after all other options have been applied.
+.TP 8
+\fB\-S\fP \fIsuffix\fP
+\fIsuffix\fP is appended to each possible completion
+after all other options have been applied.
+.TP 8
+\fB\-W\fP \fIwordlist\fP
+The \fIwordlist\fP is split using the characters in the
+.SM
+.B IFS
+special variable as delimiters, and each resultant word is expanded.
+The possible completions are the members of the resultant list which
+match the word being completed.
+.TP 8
+\fB\-X\fP \fIfilterpat\fP
+\fIfilterpat\fP is a pattern as used for pathname expansion.
+It is applied to the list of possible completions generated by the
+preceding options and arguments, and each completion matching
+\fIfilterpat\fP is removed from the list.
+A leading \fB!\fP in \fIfilterpat\fP negates the pattern; in this
+case, any completion not matching \fIfilterpat\fP is removed.
+.PD
+.PP
+The return value is true unless an invalid option is supplied, an option
+other than \fB\-p\fP or \fB\-r\fP is supplied without a \fIname\fP
+argument, an attempt is made to remove a completion specification for
+a \fIname\fP for which no specification exists, or
+an error occurs adding a completion specification.
+.RE
+.TP
+\fBcompopt\fP [\fB\-o\fP \fIoption\fP] [\fB\-DE\fP] [\fB+o\fP \fIoption\fP] [\fIname\fP]
+Modify completion options for each \fIname\fP according to the
+\fIoption\fPs, or for the
+currently-executing completion if no \fIname\fPs are supplied.
+If no \fIoption\fPs are given, display the completion options for each
+\fIname\fP or the current completion.
+The possible values of \fIoption\fP are those valid for the \fBcomplete\fP
+builtin described above.
+The \fB\-D\fP option indicates that the remaining options should
+apply to the ``default'' command completion; that is, completion attempted
+on a command for which no completion has previously been defined.
+The \fB\-E\fP option indicates that the remaining options should
+apply to ``empty'' command completion; that is, completion attempted on a
+blank line.
+.sp 1
+The return value is true unless an invalid option is supplied, an attempt
+is made to modify the options for a \fIname\fP for which no completion
+specification exists, or an output error occurs.
+.TP
+\fBcontinue\fP [\fIn\fP]
+Resume the next iteration of the enclosing
+.BR for ,
+.BR while ,
+.BR until ,
+or
+.B select
+loop.
+If
+.I n
+is specified, resume at the \fIn\fPth enclosing loop.
+.I n
+must be \(>= 1. If
+.I n
+is greater than the number of enclosing loops, the last enclosing loop
+(the ``top-level'' loop) is resumed.
+The return value is 0 unless \fIn\fP is not greater than or equal to 1.
+.TP
+\fBdeclare\fP [\fB\-aAfFgilnrtux\fP] [\fB\-p\fP] [\fIname\fP[=\fIvalue\fP] ...]
+.PD 0
+.TP
+\fBtypeset\fP [\fB\-aAfFgilnrtux\fP] [\fB\-p\fP] [\fIname\fP[=\fIvalue\fP] ...]
+.PD
+Declare variables and/or give them attributes.
+If no \fIname\fPs are given then display the values of variables.
+The
+.B \-p
+option will display the attributes and values of each
+.IR name .
+When
+.B \-p
+is used with \fIname\fP arguments, additional options,
+other than \fB\-f\fP and \fB\-F\fP, are ignored.
+When
+.B \-p
+is supplied without \fIname\fP arguments, it will display the attributes
+and values of all variables having the attributes specified by the
+additional options.
+If no other options are supplied with \fB\-p\fP, \fBdeclare\fP will display
+the attributes and values of all shell variables. The \fB\-f\fP option
+will restrict the display to shell functions.
+The
+.B \-F
+option inhibits the display of function definitions; only the
+function name and attributes are printed.
+If the \fBextdebug\fP shell option is enabled using \fBshopt\fP,
+the source file name and line number where the function is defined
+are displayed as well. The
+.B \-F
+option implies
+.BR \-f .
+The
+.B \-g
+option forces variables to be created or modified at the global scope,
+even when \fBdeclare\fP is executed in a shell function.
+It is ignored in all other cases.
+The following options can
+be used to restrict output to variables with the specified attribute or
+to give variables attributes:
+.RS
+.PD 0
+.TP
+.B \-a
+Each \fIname\fP is an indexed array variable (see
+.B Arrays
+above).
+.TP
+.B \-A
+Each \fIname\fP is an associative array variable (see
+.B Arrays
+above).
+.TP
+.B \-f
+Use function names only.
+.TP
+.B \-i
+The variable is treated as an integer; arithmetic evaluation (see
+.SM
+.B "ARITHMETIC EVALUATION"
+above) is performed when the variable is assigned a value.
+.TP
+.B \-l
+When the variable is assigned a value, all upper-case characters are
+converted to lower-case.
+The upper-case attribute is disabled.
+.TP
+.B \-n
+Give each \fIname\fP the \fInameref\fP attribute, making
+it a name reference to another variable.
+That other variable is defined by the value of \fIname\fP.
+All references, assignments, and attribute modifications
+to \fIname\fP, except for changing the
+\fB\-n\fP attribute itself, are performed on the variable referenced by
+\fIname\fP's value.
+The nameref attribute cannot be applied to array variables.
+.TP
+.B \-r
+Make \fIname\fPs readonly. These names cannot then be assigned values
+by subsequent assignment statements or unset.
+.TP
+.B \-t
+Give each \fIname\fP the \fItrace\fP attribute.
+Traced functions inherit the \fBDEBUG\fP and \fBRETURN\fP traps from
+the calling shell.
+The trace attribute has no special meaning for variables.
+.TP
+.B \-u
+When the variable is assigned a value, all lower-case characters are
+converted to upper-case.
+The lower-case attribute is disabled.
+.TP
+.B \-x
+Mark \fIname\fPs for export to subsequent commands via the environment.
+.PD
+.PP
+Using `+' instead of `\-'
+turns off the attribute instead,
+with the exceptions that \fB+a\fP
+may not be used to destroy an array variable and \fB+r\fP will not
+remove the readonly attribute.
+When used in a function,
+.B declare
+and
+.B typeset
+make each
+\fIname\fP local, as with the
+.B local
+command,
+unless the \fB\-g\fP option is supplied.
+If a variable name is followed by =\fIvalue\fP, the value of
+the variable is set to \fIvalue\fP.
+When using \fB\-a\fP or \fB\-A\fP and the compound assignment syntax to
+create array variables, additional attributes do not take effect until
+subsequent assignments.
+The return value is 0 unless an invalid option is encountered,
+an attempt is made to define a function using
+.if n ``\-f foo=bar'',
+.if t \f(CW\-f foo=bar\fP,
+an attempt is made to assign a value to a readonly variable,
+an attempt is made to assign a value to an array variable without
+using the compound assignment syntax (see
+.B Arrays
+above), one of the \fInames\fP is not a valid shell variable name,
+an attempt is made to turn off readonly status for a readonly variable,
+an attempt is made to turn off array status for an array variable,
+or an attempt is made to display a non-existent function with \fB\-f\fP.
+.RE
+.TP
+.B dirs [\fB\-clpv\fP] [+\fIn\fP] [\-\fIn\fP]
+Without options, displays the list of currently remembered directories.
+The default display is on a single line with directory names separated
+by spaces.
+Directories are added to the list with the
+.B pushd
+command; the
+.B popd
+command removes entries from the list.
+.RS
+.PD 0
+.TP
+.B \-c
+Clears the directory stack by deleting all of the entries.
+.TP
+.B \-l
+Produces a listing using full pathnames;
+the default listing format uses a tilde to denote the home directory.
+.TP
+.B \-p
+Print the directory stack with one entry per line.
+.TP
+.B \-v
+Print the directory stack with one entry per line,
+prefixing each entry with its index in the stack.
+.TP
+\fB+\fP\fIn\fP
+Displays the \fIn\fPth entry counting from the left of the list
+shown by
+.B dirs
+when invoked without options, starting with zero.
+.TP
+\fB\-\fP\fIn\fP
+Displays the \fIn\fPth entry counting from the right of the list
+shown by
+.B dirs
+when invoked without options, starting with zero.
+.PD
+.PP
+The return value is 0 unless an
+invalid option is supplied or \fIn\fP indexes beyond the end
+of the directory stack.
+.RE
+.TP
+\fBdisown\fP [\fB\-ar\fP] [\fB\-h\fP] [\fIjobspec\fP ...]
+Without options, remove each
+.I jobspec
+from the table of active jobs.
+If
+.I jobspec
+is not present, and neither the \fB\-a\fP nor the \fB\-r\fP option
+is supplied, the \fIcurrent job\fP is used.
+If the \fB\-h\fP option is given, each
+.I jobspec
+is not removed from the table, but is marked so that
+.SM
+.B SIGHUP
+is not sent to the job if the shell receives a
+.SM
+.BR SIGHUP .
+If no
+.I jobspec
+is supplied, the
+.B \-a
+option means to remove or mark all jobs; the
+.B \-r
+option without a
+.I jobspec
+argument restricts operation to running jobs.
+The return value is 0 unless a
+.I jobspec
+does not specify a valid job.
+.TP
+\fBecho\fP [\fB\-neE\fP] [\fIarg\fP ...]
+Output the \fIarg\fPs, separated by spaces, followed by a newline.
+The return status is 0 unless a write error occurs.
+If \fB\-n\fP is specified, the trailing newline is
+suppressed. If the \fB\-e\fP option is given, interpretation of
+the following backslash-escaped characters is enabled. The
+.B \-E
+option disables the interpretation of these escape characters,
+even on systems where they are interpreted by default.
+The \fBxpg_echo\fP shell option may be used to
+dynamically determine whether or not \fBecho\fP expands these
+escape characters by default.
+.B echo
+does not interpret \fB\-\-\fP to mean the end of options.
+.B echo
+interprets the following escape sequences:
+.RS
+.PD 0
+.TP
+.B \ea
+alert (bell)
+.TP
+.B \eb
+backspace
+.TP
+.B \ec
+suppress further output
+.TP
+.B \ee
+.TP
+.B \eE
+an escape character
+.TP
+.B \ef
+form feed
+.TP
+.B \en
+new line
+.TP
+.B \er
+carriage return
+.TP
+.B \et
+horizontal tab
+.TP
+.B \ev
+vertical tab
+.TP
+.B \e\e
+backslash
+.TP
+.B \e0\fInnn\fP
+the eight-bit character whose value is the octal value \fInnn\fP
+(zero to three octal digits)
+.TP
+.B \ex\fIHH\fP
+the eight-bit character whose value is the hexadecimal value \fIHH\fP
+(one or two hex digits)
+.TP
+.B \eu\fIHHHH\fP
+the Unicode (ISO/IEC 10646) character whose value is the hexadecimal value
+\fIHHHH\fP (one to four hex digits)
+.TP
+.B \eU\fIHHHHHHHH\fP
+the Unicode (ISO/IEC 10646) character whose value is the hexadecimal value
+\fIHHHHHHHH\fP (one to eight hex digits)
+.PD
+.RE
+.TP
+\fBenable\fP [\fB\-a\fP] [\fB\-dnps\fP] [\fB\-f\fP \fIfilename\fP] [\fIname\fP ...]
+Enable and disable builtin shell commands.
+Disabling a builtin allows a disk command which has the same name
+as a shell builtin to be executed without specifying a full pathname,
+even though the shell normally searches for builtins before disk commands.
+If \fB\-n\fP is used, each \fIname\fP
+is disabled; otherwise,
+\fInames\fP are enabled. For example, to use the
+.B test
+binary found via the
+.SM
+.B PATH
+instead of the shell builtin version, run
+.if t \f(CWenable -n test\fP.
+.if n ``enable -n test''.
+The
+.B \-f
+option means to load the new builtin command
+.I name
+from shared object
+.IR filename ,
+on systems that support dynamic loading. The
+.B \-d
+option will delete a builtin previously loaded with
+.BR \-f .
+If no \fIname\fP arguments are given, or if the
+.B \-p
+option is supplied, a list of shell builtins is printed.
+With no other option arguments, the list consists of all enabled
+shell builtins.
+If \fB\-n\fP is supplied, only disabled builtins are printed.
+If \fB\-a\fP is supplied, the list printed includes all builtins, with an
+indication of whether or not each is enabled.
+If \fB\-s\fP is supplied, the output is restricted to the POSIX
+\fIspecial\fP builtins.
+The return value is 0 unless a
+.I name
+is not a shell builtin or there is an error loading a new builtin
+from a shared object.
+.TP
+\fBeval\fP [\fIarg\fP ...]
+The \fIarg\fPs are read and concatenated together into a single
+command. This command is then read and executed by the shell, and
+its exit status is returned as the value of
+.BR eval .
+If there are no
+.IR args ,
+or only null arguments,
+.B eval
+returns 0.
+.TP
+\fBexec\fP [\fB\-cl\fP] [\fB\-a\fP \fIname\fP] [\fIcommand\fP [\fIarguments\fP]]
+If
+.I command
+is specified, it replaces the shell.
+No new process is created. The
+.I arguments
+become the arguments to \fIcommand\fP.
+If the
+.B \-l
+option is supplied,
+the shell places a dash at the beginning of the zeroth argument passed to
+.IR command .
+This is what
+.IR login (1)
+does. The
+.B \-c
+option causes
+.I command
+to be executed with an empty environment. If
+.B \-a
+is supplied, the shell passes
+.I name
+as the zeroth argument to the executed command.
+If
+.I command
+cannot be executed for some reason, a non-interactive shell exits,
+unless the
+.B execfail
+shell option
+is enabled. In that case, it returns failure.
+An interactive shell returns failure if the file cannot be executed.
+If
+.I command
+is not specified, any redirections take effect in the current shell,
+and the return status is 0. If there is a redirection error, the
+return status is 1.
+.TP
+\fBexit\fP [\fIn\fP]
+Cause the shell to exit
+with a status of \fIn\fP. If
+.I n
+is omitted, the exit status
+is that of the last command executed.
+A trap on
+.SM
+.B EXIT
+is executed before the shell terminates.
+.TP
+\fBexport\fP [\fB\-fn\fP\^] [\fIname\fP[=\fIword\fP]] ...
+.PD 0
+.TP
+.B export \-p
+.PD
+The supplied
+.I names
+are marked for automatic export to the environment of
+subsequently executed commands. If the
+.B \-f
+option is given, the
+.I names
+refer to functions.
+If no
+.I names
+are given, or if the
+.B \-p
+option is supplied, a list
+of names of all exported variables is printed.
+The
+.B \-n
+option causes the export property to be removed from each
+\fIname\fP.
+If a variable name is followed by =\fIword\fP, the value of
+the variable is set to \fIword\fP.
+.B export
+returns an exit status of 0 unless an invalid option is
+encountered,
+one of the \fInames\fP is not a valid shell variable name, or
+.B \-f
+is supplied with a
+.I name
+that is not a function.
+.TP
+\fBfc\fP [\fB\-e\fP \fIename\fP] [\fB\-lnr\fP] [\fIfirst\fP] [\fIlast\fP]
+.PD 0
+.TP
+\fBfc\fP \fB\-s\fP [\fIpat\fP=\fIrep\fP] [\fIcmd\fP]
+.PD
+The first form selects a range of commands from
+.I first
+to
+.I last
+from the history list and displays or edits and re-executes them.
+.I First
+and
+.I last
+may be specified as a string (to locate the last command beginning
+with that string) or as a number (an index into the history list,
+where a negative number is used as an offset from the current
+command number). If
+.I last
+is not specified it is set to
+the current command for listing (so that
+.if n ``fc \-l \-10''
+.if t \f(CWfc \-l \-10\fP
+prints the last 10 commands) and to
+.I first
+otherwise.
+If
+.I first
+is not specified it is set to the previous
+command for editing and \-16 for listing.
+.sp 1
+The
+.B \-n
+option suppresses
+the command numbers when listing. The
+.B \-r
+option reverses the order of
+the commands. If the
+.B \-l
+option is given,
+the commands are listed on
+standard output. Otherwise, the editor given by
+.I ename
+is invoked
+on a file containing those commands. If
+.I ename
+is not given, the
+value of the
+.SM
+.B FCEDIT
+variable is used, and
+the value of
+.SM
+.B EDITOR
+if
+.SM
+.B FCEDIT
+is not set. If neither variable is set,
+.FN vi
+is used. When editing is complete, the edited commands are
+echoed and executed.
+.sp 1
+In the second form, \fIcommand\fP is re-executed after each instance
+of \fIpat\fP is replaced by \fIrep\fP.
+\fICommand\fP is intepreted the same as \fIfirst\fP above.
+A useful alias to use with this is
+.if n ``r="fc -s"'',
+.if t \f(CWr='fc \-s'\fP,
+so that typing
+.if n ``r cc''
+.if t \f(CWr cc\fP
+runs the last command beginning with
+.if n ``cc''
+.if t \f(CWcc\fP
+and typing
+.if n ``r''
+.if t \f(CWr\fP
+re-executes the last command.
+.sp 1
+If the first form is used, the return value is 0 unless an invalid
+option is encountered or
+.I first
+or
+.I last
+specify history lines out of range.
+If the
+.B \-e
+option is supplied, the return value is the value of the last
+command executed or failure if an error occurs with the temporary
+file of commands. If the second form is used, the return status
+is that of the command re-executed, unless
+.I cmd
+does not specify a valid history line, in which case
+.B fc
+returns failure.
+.TP
+\fBfg\fP [\fIjobspec\fP]
+Resume
+.I jobspec
+in the foreground, and make it the current job.
+If
+.I jobspec
+is not present, the shell's notion of the \fIcurrent job\fP is used.
+The return value is that of the command placed into the foreground,
+or failure if run when job control is disabled or, when run with
+job control enabled, if
+.I jobspec
+does not specify a valid job or
+.I jobspec
+specifies a job that was started without job control.
+.TP
+\fBgetopts\fP \fIoptstring\fP \fIname\fP [\fIargs\fP]
+.B getopts
+is used by shell procedures to parse positional parameters.
+.I optstring
+contains the option characters to be recognized; if a character
+is followed by a colon, the option is expected to have an
+argument, which should be separated from it by white space.
+The colon and question mark characters may not be used as
+option characters.
+Each time it is invoked,
+.B getopts
+places the next option in the shell variable
+.IR name ,
+initializing
+.I name
+if it does not exist,
+and the index of the next argument to be processed into the
+variable
+.SM
+.BR OPTIND .
+.SM
+.B OPTIND
+is initialized to 1 each time the shell or a shell script
+is invoked. When an option requires an argument,
+.B getopts
+places that argument into the variable
+.SM
+.BR OPTARG .
+The shell does not reset
+.SM
+.B OPTIND
+automatically; it must be manually reset between multiple
+calls to
+.B getopts
+within the same shell invocation if a new set of parameters
+is to be used.
+.sp 1
+When the end of options is encountered, \fBgetopts\fP exits with a
+return value greater than zero.
+.SM
+.B OPTIND
+is set to the index of the first non-option argument,
+and \fIname\fP is set to ?.
+.sp 1
+.B getopts
+normally parses the positional parameters, but if more arguments are
+given in
+.IR args ,
+.B getopts
+parses those instead.
+.sp 1
+.B getopts
+can report errors in two ways. If the first character of
+.I optstring
+is a colon,
+.I silent
+error reporting is used. In normal operation, diagnostic messages
+are printed when invalid options or missing option arguments are
+encountered.
+If the variable
+.SM
+.B OPTERR
+is set to 0, no error messages will be displayed, even if the first
+character of
+.I optstring
+is not a colon.
+.sp 1
+If an invalid option is seen,
+.B getopts
+places ? into
+.I name
+and, if not silent,
+prints an error message and unsets
+.SM
+.BR OPTARG .
+If
+.B getopts
+is silent,
+the option character found is placed in
+.SM
+.B OPTARG
+and no diagnostic message is printed.
+.sp 1
+If a required argument is not found, and
+.B getopts
+is not silent,
+a question mark (\^\fB?\fP\^) is placed in
+.IR name ,
+.SM
+.B OPTARG
+is unset, and a diagnostic message is printed.
+If
+.B getopts
+is silent, then a colon (\^\fB:\fP\^) is placed in
+.I name
+and
+.SM
+.B OPTARG
+is set to the option character found.
+.sp 1
+.B getopts
+returns true if an option, specified or unspecified, is found.
+It returns false if the end of options is encountered or an
+error occurs.
+.TP
+\fBhash\fP [\fB\-lr\fP] [\fB\-p\fP \fIfilename\fP] [\fB\-dt\fP] [\fIname\fP]
+Each time \fBhash\fP is invoked,
+the full pathname of the command
+.I name
+is determined by searching
+the directories in
+.B $PATH
+and remembered. Any previously-remembered pathname is discarded.
+If the
+.B \-p
+option is supplied, no path search is performed, and
+.I filename
+is used as the full filename of the command.
+The
+.B \-r
+option causes the shell to forget all
+remembered locations.
+The
+.B \-d
+option causes the shell to forget the remembered location of each \fIname\fP.
+If the
+.B \-t
+option is supplied, the full pathname to which each \fIname\fP corresponds
+is printed. If multiple \fIname\fP arguments are supplied with \fB\-t\fP,
+the \fIname\fP is printed before the hashed full pathname.
+The
+.B \-l
+option causes output to be displayed in a format that may be reused as input.
+If no arguments are given, or if only \fB\-l\fP is supplied,
+information about remembered commands is printed.
+The return status is true unless a
+.I name
+is not found or an invalid option is supplied.
+.TP
+\fBhelp\fP [\fB\-dms\fP] [\fIpattern\fP]
+Display helpful information about builtin commands. If
+.I pattern
+is specified,
+.B help
+gives detailed help on all commands matching
+.IR pattern ;
+otherwise help for all the builtins and shell control structures
+is printed.
+.RS
+.PD 0
+.TP
+.B \-d
+Display a short description of each \fIpattern\fP
+.TP
+.B \-m
+Display the description of each \fIpattern\fP in a manpage-like format
+.TP
+.B \-s
+Display only a short usage synopsis for each \fIpattern\fP
+.PD
+.PP
+The return status is 0 unless no command matches
+.IR pattern .
+.RE
+.TP
+\fBhistory [\fIn\fP]
+.PD 0
+.TP
+\fBhistory\fP \fB\-c\fP
+.TP
+\fBhistory \-d\fP \fIoffset\fP
+.TP
+\fBhistory\fP \fB\-anrw\fP [\fIfilename\fP]
+.TP
+\fBhistory\fP \fB\-p\fP \fIarg\fP [\fIarg ...\fP]
+.TP
+\fBhistory\fP \fB\-s\fP \fIarg\fP [\fIarg ...\fP]
+.PD
+With no options, display the command
+history list with line numbers. Lines listed
+with a
+.B *
+have been modified. An argument of
+.I n
+lists only the last
+.I n
+lines.
+If the shell variable
+.SM
+.B HISTTIMEFORMAT
+is set and not null,
+it is used as a format string for \fIstrftime\fP(3) to display
+the time stamp associated with each displayed history entry.
+No intervening blank is printed between the formatted time stamp
+and the history line.
+If \fIfilename\fP is supplied, it is used as the
+name of the history file; if not, the value of
+.SM
+.B HISTFILE
+is used. Options, if supplied, have the following meanings:
+.RS
+.PD 0
+.TP
+.B \-c
+Clear the history list by deleting all the entries.
+.TP
+\fB\-d\fP \fIoffset\fP
+Delete the history entry at position \fIoffset\fP.
+.TP
+.B \-a
+Append the ``new'' history lines (history lines entered since the
+beginning of the current \fBbash\fP session) to the history file.
+.TP
+.B \-n
+Read the history lines not already read from the history
+file into the current history list. These are lines
+appended to the history file since the beginning of the
+current \fBbash\fP session.
+.TP
+.B \-r
+Read the contents of the history file
+and append them to the current history list.
+.TP
+.B \-w
+Write the current history list to the history file, overwriting the
+history file's contents.
+.TP
+.B \-p
+Perform history substitution on the following \fIargs\fP and display
+the result on the standard output.
+Does not store the results in the history list.
+Each \fIarg\fP must be quoted to disable normal history expansion.
+.TP
+.B \-s
+Store the
+.I args
+in the history list as a single entry. The last command in the
+history list is removed before the
+.I args
+are added.
+.PD
+.PP
+If the
+.SM
+.B HISTTIMEFORMAT
+variable is set, the time stamp information
+associated with each history entry is written to the history file,
+marked with the history comment character.
+When the history file is read, lines beginning with the history
+comment character followed immediately by a digit are interpreted
+as timestamps for the previous history line.
+The return value is 0 unless an invalid option is encountered, an
+error occurs while reading or writing the history file, an invalid
+\fIoffset\fP is supplied as an argument to \fB\-d\fP, or the
+history expansion supplied as an argument to \fB\-p\fP fails.
+.RE
+.TP
+\fBjobs\fP [\fB\-lnprs\fP] [ \fIjobspec\fP ... ]
+.PD 0
+.TP
+\fBjobs\fP \fB\-x\fP \fIcommand\fP [ \fIargs\fP ... ]
+.PD
+The first form lists the active jobs. The options have the following
+meanings:
+.RS
+.PD 0
+.TP
+.B \-l
+List process IDs
+in addition to the normal information.
+.TP
+.B \-n
+Display information only about jobs that have changed status since
+the user was last notified of their status.
+.TP
+.B \-p
+List only the process ID of the job's process group
+leader.
+.TP
+.B \-r
+Display only running jobs.
+.TP
+.B \-s
+Display only stopped jobs.
+.PD
+.PP
+If
+.I jobspec
+is given, output is restricted to information about that job.
+The return status is 0 unless an invalid option is encountered
+or an invalid
+.I jobspec
+is supplied.
+.PP
+If the
+.B \-x
+option is supplied,
+.B jobs
+replaces any
+.I jobspec
+found in
+.I command
+or
+.I args
+with the corresponding process group ID, and executes
+.I command
+passing it
+.IR args ,
+returning its exit status.
+.RE
+.TP
+\fBkill\fP [\fB\-s\fP \fIsigspec\fP | \fB\-n\fP \fIsignum\fP | \fB\-\fP\fIsigspec\fP] [\fIpid\fP | \fIjobspec\fP] ...
+.PD 0
+.TP
+\fBkill\fP \fB\-l\fP [\fIsigspec\fP | \fIexit_status\fP]
+.PD
+Send the signal named by
+.I sigspec
+or
+.I signum
+to the processes named by
+.I pid
+or
+.IR jobspec .
+.I sigspec
+is either a case-insensitive signal name such as
+.SM
+.B SIGKILL
+(with or without the
+.SM
+.B SIG
+prefix) or a signal number;
+.I signum
+is a signal number.
+If
+.I sigspec
+is not present, then
+.SM
+.B SIGTERM
+is assumed.
+An argument of
+.B \-l
+lists the signal names.
+If any arguments are supplied when
+.B \-l
+is given, the names of the signals corresponding to the arguments are
+listed, and the return status is 0.
+The \fIexit_status\fP argument to
+.B \-l
+is a number specifying either a signal number or the exit status of
+a process terminated by a signal.
+.B kill
+returns true if at least one signal was successfully sent, or false
+if an error occurs or an invalid option is encountered.
+.TP
+\fBlet\fP \fIarg\fP [\fIarg\fP ...]
+Each
+.I arg
+is an arithmetic expression to be evaluated (see
+.SM
+.B "ARITHMETIC EVALUATION"
+above).
+If the last
+.I arg
+evaluates to 0,
+.B let
+returns 1; 0 is returned otherwise.
+.TP
+\fBlocal\fP [\fIoption\fP] [\fIname\fP[=\fIvalue\fP] ...]
+For each argument, a local variable named
+.I name
+is created, and assigned
+.IR value .
+The \fIoption\fP can be any of the options accepted by \fBdeclare\fP.
+When
+.B local
+is used within a function, it causes the variable
+.I name
+to have a visible scope restricted to that function and its children.
+With no operands,
+.B local
+writes a list of local variables to the standard output. It is
+an error to use
+.B local
+when not within a function. The return status is 0 unless
+.B local
+is used outside a function, an invalid
+.I name
+is supplied, or
+\fIname\fP is a readonly variable.
+.TP
+.B logout
+Exit a login shell.
+.TP
+\fBmapfile\fP [\fB\-d\fP \fIdelim\fP] [\fB\-n\fP \fIcount\fP] [\fB\-O\fP \fIorigin\fP] [\fB\-s\fP \fIcount\fP] [\fB\-t\fP] [\fB\-u\fP \fIfd\fP] [\fB\-C\fP \fIcallback\fP] [\fB\-c\fP \fIquantum\fP] [\fIarray\fP]
+.PD 0
+.TP
+\fBreadarray\fP [\fB\-d\fP \fIdelim\fP] [\fB\-n\fP \fIcount\fP] [\fB\-O\fP \fIorigin\fP] [\fB\-s\fP \fIcount\fP] [\fB\-t\fP] [\fB\-u\fP \fIfd\fP] [\fB\-C\fP \fIcallback\fP] [\fB\-c\fP \fIquantum\fP] [\fIarray\fP]
+.PD
+Read lines from the standard input into the indexed array variable
+.IR array ,
+or from file descriptor
+.IR fd
+if the
+.B \-u
+option is supplied.
+The variable
+.SM
+.B MAPFILE
+is the default \fIarray\fP.
+Options, if supplied, have the following meanings:
+.RS
+.PD 0
+.TP
+.B \-d
+The first character of \fIdelim\fP is used to terminate each input line,
+rather than newline.
+.TP
+.B \-n
+Copy at most
+.I count
+lines. If \fIcount\fP is 0, all lines are copied.
+.TP
+.B \-O
+Begin assigning to
+.I array
+at index
+.IR origin .
+The default index is 0.
+.TP
+.B \-s
+Discard the first \fIcount\fP lines read.
+.TP
+.B \-t
+Remove a trailing newline from each line read.
+.TP
+.B \-u
+Read lines from file descriptor \fIfd\fP instead of the standard input.
+.TP
+.B \-C
+Evaluate
+.I callback
+each time \fIquantum\fP lines are read. The \fB\-c\fP option specifies
+.IR quantum .
+.TP
+.B \-c
+Specify the number of lines read between each call to
+.IR callback .
+.PD
+.PP
+If
+.B \-C
+is specified without
+.BR \-c ,
+the default quantum is 5000.
+When \fIcallback\fP is evaluated, it is supplied the index of the next
+array element to be assigned and the line to be assigned to that element
+as additional arguments.
+\fIcallback\fP is evaluated after the line is read but before the
+array element is assigned.
+.PP
+If not supplied with an explicit origin, \fBmapfile\fP will clear \fIarray\fP
+before assigning to it.
+.PP
+\fBmapfile\fP returns successfully unless an invalid option or option
+argument is supplied, \fIarray\fP is invalid or unassignable, or if
+\fIarray\fP is not an indexed array.
+.RE
+.TP
+\fBpopd\fP [\-\fBn\fP] [+\fIn\fP] [\-\fIn\fP]
+Removes entries from the directory stack. With no arguments,
+removes the top directory from the stack, and performs a
+.B cd
+to the new top directory.
+Arguments, if supplied, have the following meanings:
+.RS
+.PD 0
+.TP
+.B \-n
+Suppresses the normal change of directory when removing directories
+from the stack, so that only the stack is manipulated.
+.TP
+\fB+\fP\fIn\fP
+Removes the \fIn\fPth entry counting from the left of the list
+shown by
+.BR dirs ,
+starting with zero. For example:
+.if n ``popd +0''
+.if t \f(CWpopd +0\fP
+removes the first directory,
+.if n ``popd +1''
+.if t \f(CWpopd +1\fP
+the second.
+.TP
+\fB\-\fP\fIn\fP
+Removes the \fIn\fPth entry counting from the right of the list
+shown by
+.BR dirs ,
+starting with zero. For example:
+.if n ``popd -0''
+.if t \f(CWpopd -0\fP
+removes the last directory,
+.if n ``popd -1''
+.if t \f(CWpopd -1\fP
+the next to last.
+.PD
+.PP
+If the
+.B popd
+command is successful, a
+.B dirs
+is performed as well, and the return status is 0.
+.B popd
+returns false if an invalid option is encountered, the directory stack
+is empty, a non-existent directory stack entry is specified, or the
+directory change fails.
+.RE
+.TP
+\fBprintf\fP [\fB\-v\fP \fIvar\fP] \fIformat\fP [\fIarguments\fP]
+Write the formatted \fIarguments\fP to the standard output under the
+control of the \fIformat\fP.
+The \fB\-v\fP option causes the output to be assigned to the variable
+\fIvar\fP rather than being printed to the standard output.
+.sp 1
+The \fIformat\fP is a character string which contains three types of objects:
+plain characters, which are simply copied to standard output, character
+escape sequences, which are converted and copied to the standard output, and
+format specifications, each of which causes printing of the next successive
+\fIargument\fP.
+In addition to the standard \fIprintf\fP(1) format specifications,
+\fBprintf\fP interprets the following extensions:
+.RS
+.PD 0
+.TP
+.B %b
+causes
+\fBprintf\fP to expand backslash escape sequences in the corresponding
+\fIargument\fP (except that \fB\ec\fP terminates output, backslashes in
+\fB\e\(aq\fP, \fB\e"\fP, and \fB\e?\fP are not removed, and octal escapes
+beginning with \fB\e0\fP may contain up to four digits).
+.TP
+.B %q
+causes \fBprintf\fP to output the corresponding
+\fIargument\fP in a format that can be reused as shell input.
+.TP
+.B %(\fIdatefmt\fP)T
+causes \fBprintf\fP to output the date-time string resulting from using
+\fIdatefmt\fP as a format string for \fIstrftime\fP(3).
+The corresponding \fIargument\fP is an integer representing the number of
+seconds since the epoch.
+Two special argument values may be used: -1 represents the current
+time, and -2 represents the time the shell was invoked.
+If no argument is specified, conversion behaves as if -1 had been given.
+This is an exception to the usual \fBprintf\fP behavior.
+.PD
+.PP
+Arguments to non-string format specifiers are treated as C constants,
+except that a leading plus or minus sign is allowed, and if the leading
+character is a single or double quote, the value is the ASCII value of
+the following character.
+.PP
+The \fIformat\fP is reused as necessary to consume all of the \fIarguments\fP.
+If the \fIformat\fP requires more \fIarguments\fP than are supplied, the
+extra format specifications behave as if a zero value or null string, as
+appropriate, had been supplied.
+The return value is zero on success, non-zero on failure.
+.RE
+.TP
+\fBpushd\fP [\fB\-n\fP] [+\fIn\fP] [\-\fIn\fP]
+.PD 0
+.TP
+\fBpushd\fP [\fB\-n\fP] [\fIdir\fP]
+.PD
+Adds a directory to the top of the directory stack, or rotates
+the stack, making the new top of the stack the current working
+directory. With no arguments, exchanges the top two directories
+and returns 0, unless the directory stack is empty.
+Arguments, if supplied, have the following meanings:
+.RS
+.PD 0
+.TP
+.B \-n
+Suppresses the normal change of directory when adding directories
+to the stack, so that only the stack is manipulated.
+.TP
+\fB+\fP\fIn\fP
+Rotates the stack so that the \fIn\fPth directory
+(counting from the left of the list shown by
+.BR dirs ,
+starting with zero)
+is at the top.
+.TP
+\fB\-\fP\fIn\fP
+Rotates the stack so that the \fIn\fPth directory
+(counting from the right of the list shown by
+.BR dirs ,
+starting with zero) is at the top.
+.TP
+.I dir
+Adds
+.I dir
+to the directory stack at the top, making it the
+new current working directory as if it had been supplied as the argument
+to the \fBcd\fP builtin.
+.PD
+.PP
+If the
+.B pushd
+command is successful, a
+.B dirs
+is performed as well.
+If the first form is used,
+.B pushd
+returns 0 unless the cd to
+.I dir
+fails. With the second form,
+.B pushd
+returns 0 unless the directory stack is empty,
+a non-existent directory stack element is specified,
+or the directory change to the specified new current directory
+fails.
+.RE
+.TP
+\fBpwd\fP [\fB\-LP\fP]
+Print the absolute pathname of the current working directory.
+The pathname printed contains no symbolic links if the
+.B \-P
+option is supplied or the
+.B \-o physical
+option to the
+.B set
+builtin command is enabled.
+If the
+.B \-L
+option is used, the pathname printed may contain symbolic links.
+The return status is 0 unless an error occurs while
+reading the name of the current directory or an
+invalid option is supplied.
+.TP
+\fBread\fP [\fB\-ers\fP] [\fB\-a\fP \fIaname\fP] [\fB\-d\fP \fIdelim\fP] [\fB\-i\fP \fItext\fP] [\fB\-n\fP \fInchars\fP] [\fB\-N\fP \fInchars\fP] [\fB\-p\fP \fIprompt\fP] [\fB\-t\fP \fItimeout\fP] [\fB\-u\fP \fIfd\fP] [\fIname\fP ...]
+One line is read from the standard input, or from the file descriptor
+\fIfd\fP supplied as an argument to the \fB\-u\fP option, and the first word
+is assigned to the first
+.IR name ,
+the second word to the second
+.IR name ,
+and so on, with leftover words and their intervening separators assigned
+to the last
+.IR name .
+If there are fewer words read from the input stream than names,
+the remaining names are assigned empty values.
+The characters in
+.SM
+.B IFS
+are used to split the line into words using the same rules the shell
+uses for expansion (described above under \fBWord Splitting\fP).
+The backslash character (\fB\e\fP) may be used to remove any special
+meaning for the next character read and for line continuation.
+Options, if supplied, have the following meanings:
+.RS
+.PD 0
+.TP
+.B \-a \fIaname\fP
+The words are assigned to sequential indices
+of the array variable
+.IR aname ,
+starting at 0.
+.I aname
+is unset before any new values are assigned.
+Other \fIname\fP arguments are ignored.
+.TP
+.B \-d \fIdelim\fP
+The first character of \fIdelim\fP is used to terminate the input line,
+rather than newline.
+.TP
+.B \-e
+If the standard input
+is coming from a terminal,
+.B readline
+(see
+.SM
+.B READLINE
+above) is used to obtain the line.
+Readline uses the current (or default, if line editing was not previously
+active) editing settings.
+.TP
+.B \-i \fItext\fP
+If
+.B readline
+is being used to read the line, \fItext\fP is placed into the editing
+buffer before editing begins.
+.TP
+.B \-n \fInchars\fP
+\fBread\fP returns after reading \fInchars\fP characters rather than
+waiting for a complete line of input, but honor a delimiter if fewer
+than \fInchars\fP characters are read before the delimiter.
+.TP
+.B \-N \fInchars\fP
+\fBread\fP returns after reading exactly \fInchars\fP characters rather
+than waiting for a complete line of input, unless EOF is encountered or
+\fBread\fP times out.
+Delimiter characters encountered in the input are
+not treated specially and do not cause \fBread\fP to return until
+\fInchars\fP characters are read.
+.TP
+.B \-p \fIprompt\fP
+Display \fIprompt\fP on standard error, without a
+trailing newline, before attempting to read any input. The prompt
+is displayed only if input is coming from a terminal.
+.TP
+.B \-r
+Backslash does not act as an escape character.
+The backslash is considered to be part of the line.
+In particular, a backslash-newline pair may not be used as a line
+continuation.
+.TP
+.B \-s
+Silent mode. If input is coming from a terminal, characters are
+not echoed.
+.TP
+.B \-t \fItimeout\fP
+Cause \fBread\fP to time out and return failure if a complete line of
+input (or a specified number of characters)
+is not read within \fItimeout\fP seconds.
+\fItimeout\fP may be a decimal number with a fractional portion following
+the decimal point.
+This option is only effective if \fBread\fP is reading input from a
+terminal, pipe, or other special file; it has no effect when reading
+from regular files.
+If \fBread\fP times out, \fBread\fP saves any partial input read into
+the specified variable \fIname\fP.
+If \fItimeout\fP is 0, \fBread\fP returns immediately, without trying to
+read any data. The exit status is 0 if input is available on
+the specified file descriptor, non-zero otherwise.
+The exit status is greater than 128 if the timeout is exceeded.
+.TP
+.B \-u \fIfd\fP
+Read input from file descriptor \fIfd\fP.
+.PD
+.PP
+If no
+.I names
+are supplied, the line read is assigned to the variable
+.SM
+.BR REPLY .
+The return code is zero, unless end-of-file is encountered, \fBread\fP
+times out (in which case the return code is greater than 128),
+a variable assignment error (such as assigning to a readonly variable) occurs,
+or an invalid file descriptor is supplied as the argument to \fB\-u\fP.
+.RE
+.TP
+\fBreadonly\fP [\fB\-aAf\fP] [\fB\-p\fP] [\fIname\fP[=\fIword\fP] ...]
+.PD
+The given
+\fInames\fP are marked readonly; the values of these
+.I names
+may not be changed by subsequent assignment.
+If the
+.B \-f
+option is supplied, the functions corresponding to the
+\fInames\fP are so
+marked.
+The
+.B \-a
+option restricts the variables to indexed arrays; the
+.B \-A
+option restricts the variables to associative arrays.
+If both options are supplied,
+.B \-A
+takes precedence.
+If no
+.I name
+arguments are given, or if the
+.B \-p
+option is supplied, a list of all readonly names is printed.
+The other options may be used to restrict the output to a subset of
+the set of readonly names.
+The
+.B \-p
+option causes output to be displayed in a format that
+may be reused as input.
+If a variable name is followed by =\fIword\fP, the value of
+the variable is set to \fIword\fP.
+The return status is 0 unless an invalid option is encountered,
+one of the
+.I names
+is not a valid shell variable name, or
+.B \-f
+is supplied with a
+.I name
+that is not a function.
+.TP
+\fBreturn\fP [\fIn\fP]
+Causes a function to stop executing and return the value specified by
+.I n
+to its caller.
+If
+.I n
+is omitted, the return status is that of the last command
+executed in the function body.
+If \fBreturn\fP is executed by a trap handler, the last command used to
+determine the status is the last command executed before the trap handler.
+if \fBreturn\fP is executed during a \fBDEBUG\fP trap, the last command
+used to determine the status is the last command executed by the trap
+handler before \fBreturn\fP was invoked.
+If
+.B return
+is used outside a function,
+but during execution of a script by the
+.B .
+(\fBsource\fP) command, it causes the shell to stop executing
+that script and return either
+.I n
+or the exit status of the last command executed within the
+script as the exit status of the script.
+If \fIn\fP is supplied, the return value is its least significant
+8 bits.
+The return status is non-zero if
+.B return
+is supplied a non-numeric argument, or
+is used outside a
+function and not during execution of a script by \fB.\fP\^ or \fBsource\fP.
+Any command associated with the \fBRETURN\fP trap is executed
+before execution resumes after the function or script.
+.TP
+\fBset\fP [\fB\-\-abefhkmnptuvxBCEHPT\fP] [\fB\-o\fP \fIoption\-name\fP] [\fIarg\fP ...]
+.PD 0
+.TP
+\fBset\fP [\fB+abefhkmnptuvxBCEHPT\fP] [\fB+o\fP \fIoption\-name\fP] [\fIarg\fP ...]
+.PD
+Without options, the name and value of each shell variable are displayed
+in a format that can be reused as input
+for setting or resetting the currently-set variables.
+Read-only variables cannot be reset.
+In \fIposix\fP mode, only shell variables are listed.
+The output is sorted according to the current locale.
+When options are specified, they set or unset shell attributes.
+Any arguments remaining after option processing are treated
+as values for the positional parameters and are assigned, in order, to
+.BR $1 ,
+.BR $2 ,
+.B ...
+.BR $\fIn\fP .
+Options, if specified, have the following meanings:
+.RS
+.PD 0
+.TP 8
+.B \-a
+Automatically mark variables and functions which are modified or
+created for export to the environment of subsequent commands.
+.TP 8
+.B \-b
+Report the status of terminated background jobs
+immediately, rather than before the next primary prompt. This is
+effective only when job control is enabled.
+.TP 8
+.B \-e
+Exit immediately if a
+\fIpipeline\fP (which may consist of a single \fIsimple command\fP),
+a \fIlist\fP,
+or a \fIcompound command\fP
+(see
+.SM
+.B SHELL GRAMMAR
+above), exits with a non-zero status.
+The shell does not exit if the
+command that fails is part of the command list immediately following a
+.B while
+or
+.B until
+keyword,
+part of the test following the
+.B if
+or
+.B elif
+reserved words, part of any command executed in a
+.B &&
+or
+.B ||
+list except the command following the final \fB&&\fP or \fB||\fP,
+any command in a pipeline but the last,
+or if the command's return value is
+being inverted with
+.BR ! .
+If a compound command other than a subshell
+returns a non-zero status because a command failed
+while \fB\-e\fP was being ignored, the shell does not exit.
+A trap on \fBERR\fP, if set, is executed before the shell exits.
+This option applies to the shell environment and each subshell environment
+separately (see
+.SM
+.B "COMMAND EXECUTION ENVIRONMENT"
+above), and may cause
+subshells to exit before executing all the commands in the subshell.
+.if t .sp 0.5
+.if n .sp 1
+If a compound command or shell function executes in a context
+where \fB\-e\fP is being ignored,
+none of the commands executed within the compound command or function body
+will be affected by the \fB\-e\fP setting, even if \fB\-e\fP is set
+and a command returns a failure status.
+If a compound command or shell function sets \fB\-e\fP while executing in
+a context where \fB\-e\fP is ignored, that setting will not have any
+effect until the compound command or the command containing the function
+call completes.
+.TP 8
+.B \-f
+Disable pathname expansion.
+.TP 8
+.B \-h
+Remember the location of commands as they are looked up for execution.
+This is enabled by default.
+.TP 8
+.B \-k
+All arguments in the form of assignment statements
+are placed in the environment for a command, not just
+those that precede the command name.
+.TP 8
+.B \-m
+Monitor mode. Job control is enabled. This option is on
+by default for interactive shells on systems that support
+it (see
+.SM
+.B JOB CONTROL
+above).
+All processes run in a separate process group.
+When a background job completes, the shell prints a line
+containing its exit status.
+.TP 8
+.B \-n
+Read commands but do not execute them.
+This may be used to check a shell script for syntax errors.
+This is ignored by interactive shells.
+.TP 8
+.B \-o \fIoption\-name\fP
+The \fIoption\-name\fP can be one of the following:
+.RS
+.TP 8
+.B allexport
+Same as
+.BR \-a .
+.TP 8
+.B braceexpand
+Same as
+.BR \-B .
+.TP 8
+.B emacs
+Use an emacs-style command line editing interface. This is enabled
+by default when the shell is interactive, unless the shell is started
+with the
+.B \-\-noediting
+option.
+This also affects the editing interface used for \fBread \-e\fP.
+.TP 8
+.B errexit
+Same as
+.BR \-e .
+.TP 8
+.B errtrace
+Same as
+.BR \-E .
+.TP 8
+.B functrace
+Same as
+.BR \-T .
+.TP 8
+.B hashall
+Same as
+.BR \-h .
+.TP 8
+.B histexpand
+Same as
+.BR \-H .
+.TP 8
+.B history
+Enable command history, as described above under
+.SM
+.BR HISTORY .
+This option is on by default in interactive shells.
+.TP 8
+.B ignoreeof
+The effect is as if the shell command
+.if t \f(CWIGNOREEOF=10\fP
+.if n ``IGNOREEOF=10''
+had been executed
+(see
+.B Shell Variables
+above).
+.TP 8
+.B keyword
+Same as
+.BR \-k .
+.TP 8
+.B monitor
+Same as
+.BR \-m .
+.TP 8
+.B noclobber
+Same as
+.BR \-C .
+.TP 8
+.B noexec
+Same as
+.BR \-n .
+.TP 8
+.B noglob
+Same as
+.BR \-f .
+.TP 8
+.B nolog
+Currently ignored.
+.TP 8
+.B notify
+Same as
+.BR \-b .
+.TP 8
+.B nounset
+Same as
+.BR \-u .
+.TP 8
+.B onecmd
+Same as
+.BR \-t .
+.TP 8
+.B physical
+Same as
+.BR \-P .
+.TP 8
+.B pipefail
+If set, the return value of a pipeline is the value of the last
+(rightmost) command to exit with a non-zero status, or zero if all
+commands in the pipeline exit successfully.
+This option is disabled by default.
+.TP 8
+.B posix
+Change the behavior of
+.B bash
+where the default operation differs
+from the POSIX standard to match the standard (\fIposix mode\fP).
+See
+.SM
+.B "SEE ALSO"
+below for a reference to a document that details how posix mode affects
+bash's behavior.
+.TP 8
+.B privileged
+Same as
+.BR \-p .
+.TP 8
+.B verbose
+Same as
+.BR \-v .
+.TP 8
+.B vi
+Use a vi-style command line editing interface.
+This also affects the editing interface used for \fBread \-e\fP.
+.TP 8
+.B xtrace
+Same as
+.BR \-x .
+.sp .5
+.PP
+If
+.B \-o
+is supplied with no \fIoption\-name\fP, the values of the current options are
+printed.
+If
+.B +o
+is supplied with no \fIoption\-name\fP, a series of
+.B set
+commands to recreate the current option settings is displayed on
+the standard output.
+.RE
+.TP 8
+.B \-p
+Turn on
+.I privileged
+mode. In this mode, the
+.SM
+.B $ENV
+and
+.SM
+.B $BASH_ENV
+files are not processed, shell functions are not inherited from the
+environment, and the
+.SM
+.BR SHELLOPTS ,
+.SM
+.BR BASHOPTS ,
+.SM
+.BR CDPATH ,
+and
+.SM
+.B GLOBIGNORE
+variables, if they appear in the environment, are ignored.
+If the shell is started with the effective user (group) id not equal to the
+real user (group) id, and the \fB\-p\fP option is not supplied, these actions
+are taken and the effective user id is set to the real user id.
+If the \fB\-p\fP option is supplied at startup, the effective user id is
+not reset.
+Turning this option off causes the effective user
+and group ids to be set to the real user and group ids.
+.TP 8
+.B \-t
+Exit after reading and executing one command.
+.TP 8
+.B \-u
+Treat unset variables and parameters other than the special
+parameters "@" and "*" as an error when performing
+parameter expansion. If expansion is attempted on an
+unset variable or parameter, the shell prints an error message, and,
+if not interactive, exits with a non-zero status.
+.TP 8
+.B \-v
+Print shell input lines as they are read.
+.TP 8
+.B \-x
+After expanding each \fIsimple command\fP,
+\fBfor\fP command, \fBcase\fP command, \fBselect\fP command, or
+arithmetic \fBfor\fP command, display the expanded value of
+.SM
+.BR PS4 ,
+followed by the command and its expanded arguments
+or associated word list.
+.TP 8
+.B \-B
+The shell performs brace expansion (see
+.B Brace Expansion
+above). This is on by default.
+.TP 8
+.B \-C
+If set,
+.B bash
+does not overwrite an existing file with the
+.BR > ,
+.BR >& ,
+and
+.B <>
+redirection operators. This may be overridden when
+creating output files by using the redirection operator
+.B >|
+instead of
+.BR > .
+.TP 8
+.B \-E
+If set, any trap on \fBERR\fP is inherited by shell functions, command
+substitutions, and commands executed in a subshell environment.
+The \fBERR\fP trap is normally not inherited in such cases.
+.TP 8
+.B \-H
+Enable
+.B !
+style history substitution. This option is on by
+default when the shell is interactive.
+.TP 8
+.B \-P
+If set, the shell does not resolve symbolic links when executing
+commands such as
+.B cd
+that change the current working directory. It uses the
+physical directory structure instead. By default,
+.B bash
+follows the logical chain of directories when performing commands
+which change the current directory.
+.TP 8
+.B \-T
+If set, any traps on \fBDEBUG\fP and \fBRETURN\fP are inherited by shell
+functions, command substitutions, and commands executed in a
+subshell environment.
+The \fBDEBUG\fP and \fBRETURN\fP traps are normally not inherited
+in such cases.
+.TP 8
+.B \-\-
+If no arguments follow this option, then the positional parameters are
+unset. Otherwise, the positional parameters are set to the
+\fIarg\fPs, even if some of them begin with a
+.BR \- .
+.TP 8
+.B \-
+Signal the end of options, cause all remaining \fIarg\fPs to be
+assigned to the positional parameters. The
+.B \-x
+and
+.B \-v
+options are turned off.
+If there are no \fIarg\fPs,
+the positional parameters remain unchanged.
+.PD
+.PP
+The options are off by default unless otherwise noted.
+Using + rather than \- causes these options to be turned off.
+The options can also be specified as arguments to an invocation of
+the shell.
+The current set of options may be found in
+.BR $\- .
+The return status is always true unless an invalid option is encountered.
+.RE
+.TP
+\fBshift\fP [\fIn\fP]
+The positional parameters from \fIn\fP+1 ... are renamed to
+.B $1
+.B ....
+Parameters represented by the numbers \fB$#\fP
+down to \fB$#\fP\-\fIn\fP+1 are unset.
+.I n
+must be a non-negative number less than or equal to \fB$#\fP.
+If
+.I n
+is 0, no parameters are changed.
+If
+.I n
+is not given, it is assumed to be 1.
+If
+.I n
+is greater than \fB$#\fP, the positional parameters are not changed.
+The return status is greater than zero if
+.I n
+is greater than
+.B $#
+or less than zero; otherwise 0.
+.TP
+\fBshopt\fP [\fB\-pqsu\fP] [\fB\-o\fP] [\fIoptname\fP ...]
+Toggle the values of settings controlling optional shell behavior.
+The settings can be either those listed below, or, if the
+.B \-o
+option is used, those available with the
+.B \-o
+option to the \fBset\fP builtin command.
+With no options, or with the
+.B \-p
+option, a list of all settable options is displayed, with
+an indication of whether or not each is set.
+The \fB\-p\fP option causes output to be displayed in a form that
+may be reused as input.
+Other options have the following meanings:
+.RS
+.PD 0
+.TP
+.B \-s
+Enable (set) each \fIoptname\fP.
+.TP
+.B \-u
+Disable (unset) each \fIoptname\fP.
+.TP
+.B \-q
+Suppresses normal output (quiet mode); the return status indicates
+whether the \fIoptname\fP is set or unset.
+If multiple \fIoptname\fP arguments are given with
+.BR \-q ,
+the return status is zero if all \fIoptnames\fP are enabled; non-zero
+otherwise.
+.TP
+.B \-o
+Restricts the values of \fIoptname\fP to be those defined for the
+.B \-o
+option to the
+.B set
+builtin.
+.PD
+.PP
+If either
+.B \-s
+or
+.B \-u
+is used with no \fIoptname\fP arguments,
+.B shopt
+shows only those options which are set or unset, respectively.
+Unless otherwise noted, the \fBshopt\fP options are disabled (unset)
+by default.
+.PP
+The return status when listing options is zero if all \fIoptnames\fP
+are enabled, non-zero otherwise. When setting or unsetting options,
+the return status is zero unless an \fIoptname\fP is not a valid shell
+option.
+.PP
+The list of \fBshopt\fP options is:
+.if t .sp .5v
+.if n .sp 1v
+.PD 0
+.TP 8
+.B autocd
+If set, a command name that is the name of a directory is executed as if
+it were the argument to the \fBcd\fP command.
+This option is only used by interactive shells.
+.TP 8
+.B cdable_vars
+If set, an argument to the
+.B cd
+builtin command that
+is not a directory is assumed to be the name of a variable whose
+value is the directory to change to.
+.TP 8
+.B cdspell
+If set, minor errors in the spelling of a directory component in a
+.B cd
+command will be corrected.
+The errors checked for are transposed characters,
+a missing character, and one character too many.
+If a correction is found, the corrected filename is printed,
+and the command proceeds.
+This option is only used by interactive shells.
+.TP 8
+.B checkhash
+If set, \fBbash\fP checks that a command found in the hash
+table exists before trying to execute it. If a hashed command no
+longer exists, a normal path search is performed.
+.TP 8
+.B checkjobs
+If set, \fBbash\fP lists the status of any stopped and running jobs before
+exiting an interactive shell. If any jobs are running, this causes
+the exit to be deferred until a second exit is attempted without an
+intervening command (see
+.SM
+.B "JOB CONTROL"
+above). The shell always
+postpones exiting if any jobs are stopped.
+.TP 8
+.B checkwinsize
+If set, \fBbash\fP checks the window size after each command
+and, if necessary, updates the values of
+.SM
+.B LINES
+and
+.SM
+.BR COLUMNS .
+.TP 8
+.B cmdhist
+If set,
+.B bash
+attempts to save all lines of a multiple-line
+command in the same history entry. This allows
+easy re-editing of multi-line commands.
+.TP 8
+.B compat31
+If set,
+.B bash
+changes its behavior to that of version 3.1 with respect to quoted
+arguments to the \fB[[\fP conditional command's \fB=~\fP operator
+and locale-specific string comparison when using the \fB[[\fP
+conditional command's \fB<\fP and \fB>\fP operators.
+Bash versions prior to bash-4.1 use ASCII collation and
+.IR strcmp (3);
+bash-4.1 and later use the current locale's collation sequence and
+.IR strcoll (3).
+.TP 8
+.B compat32
+If set,
+.B bash
+changes its behavior to that of version 3.2 with respect to
+locale-specific string comparison when using the \fB[[\fP
+conditional command's \fB<\fP and \fB>\fP operators (see previous item).
+.TP 8
+.B compat40
+If set,
+.B bash
+changes its behavior to that of version 4.0 with respect to locale-specific
+string comparison when using the \fB[[\fP
+conditional command's \fB<\fP and \fB>\fP operators (see description of
+\fBcompat31\fP)
+and the effect of interrupting a command list.
+Bash versions 4.0 and later interrupt the list as if the shell received the
+interrupt; previous versions continue with the next command in the list.
+.TP 8
+.B compat41
+If set,
+.BR bash ,
+when in \fIposix\fP mode, treats a single quote in a double-quoted
+parameter expansion as a special character. The single quotes must match
+(an even number) and the characters between the single quotes are considered
+quoted. This is the behavior of posix mode through version 4.1.
+The default bash behavior remains as in previous versions.
+.TP 8
+.B compat42
+If set,
+.B bash
+does not process the replacement string in the pattern substitution word
+expansion using quote removal.
+.TP 8
+.B complete_fullquote
+If set,
+.B bash
+quotes all shell metacharacters in filenames and directory names when
+performing completion.
+If not set,
+.B bash
+removes metacharacters such as the dollar sign from the set of
+characters that will be quoted in completed filenames
+when these metacharacters appear in shell variable references in words to be
+completed.
+This means that dollar signs in variable names that expand to directories
+will not be quoted;
+however, any dollar signs appearing in filenames will not be quoted, either.
+This is active only when bash is using backslashes to quote completed
+filenames.
+This variable is set by default, which is the default bash behavior in
+versions through 4.2.
+.TP 8
+.B direxpand
+If set,
+.B bash
+replaces directory names with the results of word expansion when performing
+filename completion. This changes the contents of the readline editing
+buffer.
+If not set,
+.B bash
+attempts to preserve what the user typed.
+.TP 8
+.B dirspell
+If set,
+.B bash
+attempts spelling correction on directory names during word completion
+if the directory name initially supplied does not exist.
+.TP 8
+.B dotglob
+If set,
+.B bash
+includes filenames beginning with a `.' in the results of pathname
+expansion.
+.TP 8
+.B execfail
+If set, a non-interactive shell will not exit if
+it cannot execute the file specified as an argument to the
+.B exec
+builtin command. An interactive shell does not exit if
+.B exec
+fails.
+.TP 8
+.B expand_aliases
+If set, aliases are expanded as described above under
+.SM
+.BR ALIASES .
+This option is enabled by default for interactive shells.
+.TP 8
+.B extdebug
+If set, behavior intended for use by debuggers is enabled:
+.RS
+.TP
+.B 1.
+The \fB\-F\fP option to the \fBdeclare\fP builtin displays the source
+file name and line number corresponding to each function name supplied
+as an argument.
+.TP
+.B 2.
+If the command run by the \fBDEBUG\fP trap returns a non-zero value, the
+next command is skipped and not executed.
+.TP
+.B 3.
+If the command run by the \fBDEBUG\fP trap returns a value of 2, and the
+shell is executing in a subroutine (a shell function or a shell script
+executed by the \fB.\fP or \fBsource\fP builtins), the shell simulates
+a call to \fBreturn\fP.
+.TP
+.B 4.
+.SM
+.B BASH_ARGC
+and
+.SM
+.B BASH_ARGV
+are updated as described in their descriptions above.
+.TP
+.B 5.
+Function tracing is enabled: command substitution, shell functions, and
+subshells invoked with \fB(\fP \fIcommand\fP \fB)\fP inherit the
+\fBDEBUG\fP and \fBRETURN\fP traps.
+.TP
+.B 6.
+Error tracing is enabled: command substitution, shell functions, and
+subshells invoked with \fB(\fP \fIcommand\fP \fB)\fP inherit the
+\fBERR\fP trap.
+.RE
+.TP 8
+.B extglob
+If set, the extended pattern matching features described above under
+\fBPathname Expansion\fP are enabled.
+.TP 8
+.B extquote
+If set, \fB$\fP\(aq\fIstring\fP\(aq and \fB$\fP"\fIstring\fP" quoting is
+performed within \fB${\fP\fIparameter\fP\fB}\fP expansions
+enclosed in double quotes. This option is enabled by default.
+.TP 8
+.B failglob
+If set, patterns which fail to match filenames during pathname expansion
+result in an expansion error.
+.TP 8
+.B force_fignore
+If set, the suffixes specified by the
+.SM
+.B FIGNORE
+shell variable
+cause words to be ignored when performing word completion even if
+the ignored words are the only possible completions.
+See
+.SM
+\fBSHELL VARIABLES\fP
+above for a description of
+.SM
+.BR FIGNORE .
+This option is enabled by default.
+.TP 8
+.B globasciiranges
+If set, range expressions used in pattern matching bracket expressions (see
+.SM
+.B Pattern Matching
+above) behave as if in the traditional C locale when performing
+comparisons. That is, the current locale's collating sequence
+is not taken into account, so
+.B b
+will not collate between
+.B A
+and
+.BR B ,
+and upper-case and lower-case ASCII characters will collate together.
+.TP 8
+.B globstar
+If set, the pattern \fB**\fP used in a pathname expansion context will
+match all files and zero or more directories and subdirectories.
+If the pattern is followed by a \fB/\fP, only directories and
+subdirectories match.
+.TP 8
+.B gnu_errfmt
+If set, shell error messages are written in the standard GNU error
+message format.
+.TP 8
+.B histappend
+If set, the history list is appended to the file named by the value
+of the
+.SM
+.B HISTFILE
+variable when the shell exits, rather than overwriting the file.
+.TP 8
+.B histreedit
+If set, and
+.B readline
+is being used, a user is given the opportunity to re-edit a
+failed history substitution.
+.TP 8
+.B histverify
+If set, and
+.B readline
+is being used, the results of history substitution are not immediately
+passed to the shell parser. Instead, the resulting line is loaded into
+the \fBreadline\fP editing buffer, allowing further modification.
+.TP 8
+.B hostcomplete
+If set, and
+.B readline
+is being used, \fBbash\fP will attempt to perform hostname completion when a
+word containing a \fB@\fP is being completed (see
+.B Completing
+under
+.SM
+.B READLINE
+above).
+This is enabled by default.
+.TP 8
+.B huponexit
+If set, \fBbash\fP will send
+.SM
+.B SIGHUP
+to all jobs when an interactive login shell exits.
+.TP 8
+.B interactive_comments
+If set, allow a word beginning with
+.B #
+to cause that word and all remaining characters on that
+line to be ignored in an interactive shell (see
+.SM
+.B COMMENTS
+above). This option is enabled by default.
+.TP 8
+.B lastpipe
+If set, and job control is not active, the shell runs the last command of
+a pipeline not executed in the background in the current shell environment.
+.TP 8
+.B lithist
+If set, and the
+.B cmdhist
+option is enabled, multi-line commands are saved to the history with
+embedded newlines rather than using semicolon separators where possible.
+.TP 8
+.B login_shell
+The shell sets this option if it is started as a login shell (see
+.SM
+.B "INVOCATION"
+above).
+The value may not be changed.
+.TP 8
+.B mailwarn
+If set, and a file that \fBbash\fP is checking for mail has been
+accessed since the last time it was checked, the message ``The mail in
+\fImailfile\fP has been read'' is displayed.
+.TP 8
+.B no_empty_cmd_completion
+If set, and
+.B readline
+is being used,
+.B bash
+will not attempt to search the
+.SM
+.B PATH
+for possible completions when
+completion is attempted on an empty line.
+.TP 8
+.B nocaseglob
+If set,
+.B bash
+matches filenames in a case\-insensitive fashion when performing pathname
+expansion (see
+.B Pathname Expansion
+above).
+.TP 8
+.B nocasematch
+If set,
+.B bash
+matches patterns in a case\-insensitive fashion when performing matching
+while executing \fBcase\fP or \fB[[\fP conditional commands,
+when performing pattern substitution word expansions,
+or when filtering possible completions as part of programmable completion.
+.TP 8
+.B nullglob
+If set,
+.B bash
+allows patterns which match no
+files (see
+.B Pathname Expansion
+above)
+to expand to a null string, rather than themselves.
+.TP 8
+.B progcomp
+If set, the programmable completion facilities (see
+\fBProgrammable Completion\fP above) are enabled.
+This option is enabled by default.
+.TP 8
+.B promptvars
+If set, prompt strings undergo
+parameter expansion, command substitution, arithmetic
+expansion, and quote removal after being expanded as described in
+.SM
+.B PROMPTING
+above. This option is enabled by default.
+.TP 8
+.B restricted_shell
+The shell sets this option if it is started in restricted mode (see
+.SM
+.B "RESTRICTED SHELL"
+below).
+The value may not be changed.
+This is not reset when the startup files are executed, allowing
+the startup files to discover whether or not a shell is restricted.
+.TP 8
+.B shift_verbose
+If set, the
+.B shift
+builtin prints an error message when the shift count exceeds the
+number of positional parameters.
+.TP 8
+.B sourcepath
+If set, the
+\fBsource\fP (\fB.\fP) builtin uses the value of
+.SM
+.B PATH
+to find the directory containing the file supplied as an argument.
+This option is enabled by default.
+.TP 8
+.B xpg_echo
+If set, the \fBecho\fP builtin expands backslash-escape sequences
+by default.
+.RE
+.PD
+.TP
+\fBsuspend\fP [\fB\-f\fP]
+Suspend the execution of this shell until it receives a
+.SM
+.B SIGCONT
+signal. A login shell cannot be suspended; the
+.B \-f
+option can be used to override this and force the suspension.
+The return status is 0 unless the shell is a login shell and
+.B \-f
+is not supplied, or if job control is not enabled.
+.TP
+\fBtest\fP \fIexpr\fP
+.PD 0
+.TP
+\fB[\fP \fIexpr\fP \fB]\fP
+Return a status of 0 (true) or 1 (false) depending on
+the evaluation of the conditional expression
+.IR expr .
+Each operator and operand must be a separate argument.
+Expressions are composed of the primaries described above under
+.SM
+.BR "CONDITIONAL EXPRESSIONS" .
+\fBtest\fP does not accept any options, nor does it accept and ignore
+an argument of \fB\-\-\fP as signifying the end of options.
+.if t .sp 0.5
+.if n .sp 1
+Expressions may be combined using the following operators, listed
+in decreasing order of precedence.
+The evaluation depends on the number of arguments; see below.
+Operator precedence is used when there are five or more arguments.
+.RS
+.PD 0
+.TP
+.B ! \fIexpr\fP
+True if
+.I expr
+is false.
+.TP
+.B ( \fIexpr\fP )
+Returns the value of \fIexpr\fP.
+This may be used to override the normal precedence of operators.
+.TP
+\fIexpr1\fP \-\fBa\fP \fIexpr2\fP
+True if both
+.I expr1
+and
+.I expr2
+are true.
+.TP
+\fIexpr1\fP \-\fBo\fP \fIexpr2\fP
+True if either
+.I expr1
+or
+.I expr2
+is true.
+.PD
+.PP
+\fBtest\fP and \fB[\fP evaluate conditional
+expressions using a set of rules based on the number of arguments.
+.if t .sp 0.5
+.if n .sp 1
+.PD 0
+.TP
+0 arguments
+The expression is false.
+.TP
+1 argument
+The expression is true if and only if the argument is not null.
+.TP
+2 arguments
+If the first argument is \fB!\fP, the expression is true if and
+only if the second argument is null.
+If the first argument is one of the unary conditional operators listed above
+under
+.SM
+.BR "CONDITIONAL EXPRESSIONS" ,
+the expression is true if the unary test is true.
+If the first argument is not a valid unary conditional operator, the expression
+is false.
+.TP
+3 arguments
+The following conditions are applied in the order listed.
+If the second argument is one of the binary conditional operators listed above
+under
+.SM
+.BR "CONDITIONAL EXPRESSIONS" ,
+the result of the expression is the result of the binary test using
+the first and third arguments as operands.
+The \fB\-a\fP and \fB\-o\fP operators are considered binary operators
+when there are three arguments.
+If the first argument is \fB!\fP, the value is the negation of
+the two-argument test using the second and third arguments.
+If the first argument is exactly \fB(\fP and the third argument is
+exactly \fB)\fP, the result is the one-argument test of the second
+argument.
+Otherwise, the expression is false.
+.TP
+4 arguments
+If the first argument is \fB!\fP, the result is the negation of
+the three-argument expression composed of the remaining arguments.
+Otherwise, the expression is parsed and evaluated according to
+precedence using the rules listed above.
+.TP
+5 or more arguments
+The expression is parsed and evaluated according to precedence
+using the rules listed above.
+.if t .sp 0.5
+.if n .sp 1
+.LP
+When used with \fBtest\fP or \fB[\fP, the \fB<\fP and \fB>\fP operators
+sort lexicographically using ASCII ordering.
+.RE
+.PD
+.TP
+.B times
+Print the accumulated user and system times for the shell and
+for processes run from the shell. The return status is 0.
+.TP
+\fBtrap\fP [\fB\-lp\fP] [[\fIarg\fP] \fIsigspec\fP ...]
+The command
+.I arg
+is to be read and executed when the shell receives
+signal(s)
+.IR sigspec .
+If
+.I arg
+is absent (and there is a single \fIsigspec\fP) or
+.BR \- ,
+each specified signal is
+reset to its original disposition (the value it had
+upon entrance to the shell).
+If
+.I arg
+is the null string the signal specified by each
+.I sigspec
+is ignored by the shell and by the commands it invokes.
+If
+.I arg
+is not present and
+.B \-p
+has been supplied, then the trap commands associated with each
+.I sigspec
+are displayed.
+If no arguments are supplied or if only
+.B \-p
+is given,
+.B trap
+prints the list of commands associated with each signal.
+The
+.B \-l
+option causes the shell to print a list of signal names and
+their corresponding numbers.
+Each
+.I sigspec
+is either
+a signal name defined in <\fIsignal.h\fP>, or a signal number.
+Signal names are case insensitive and the
+.SM
+.B SIG
+prefix is optional.
+.if t .sp 0.5
+.if n .sp 1
+If a
+.I sigspec
+is
+.SM
+.B EXIT
+(0) the command
+.I arg
+is executed on exit from the shell.
+If a
+.I sigspec
+is
+.SM
+.BR DEBUG ,
+the command
+.I arg
+is executed before every \fIsimple command\fP, \fIfor\fP command,
+\fIcase\fP command, \fIselect\fP command, every arithmetic \fIfor\fP
+command, and before the first command executes in a shell function (see
+.SM
+.B SHELL GRAMMAR
+above).
+Refer to the description of the \fBextdebug\fP option to the
+\fBshopt\fP builtin for details of its effect on the \fBDEBUG\fP trap.
+If a
+.I sigspec
+is
+.SM
+.BR RETURN ,
+the command
+.I arg
+is executed each time a shell function or a script executed with
+the \fB.\fP or \fBsource\fP builtins finishes executing.
+.if t .sp 0.5
+.if n .sp 1
+If a
+.I sigspec
+is
+.SM
+.BR ERR ,
+the command
+.I arg
+is executed whenever a
+a pipeline (which may consist of a single simple
+command), a list, or a compound command returns a
+non\-zero exit status,
+subject to the following conditions.
+The
+.SM
+.B ERR
+trap is not executed if the failed
+command is part of the command list immediately following a
+.B while
+or
+.B until
+keyword,
+part of the test in an
+.I if
+statement, part of a command executed in a
+.B &&
+or
+.B ||
+list except the command following the final \fB&&\fP or \fB||\fP,
+any command in a pipeline but the last,
+or if the command's return value is
+being inverted using
+.BR ! .
+These are the same conditions obeyed by the \fBerrexit\fP (\fB\-e\fP) option.
+.if t .sp 0.5
+.if n .sp 1
+Signals ignored upon entry to the shell cannot be trapped or reset.
+Trapped signals that are not being ignored are reset to their original
+values in a subshell or subshell environment when one is created.
+The return status is false if any
+.I sigspec
+is invalid; otherwise
+.B trap
+returns true.
+.TP
+\fBtype\fP [\fB\-aftpP\fP] \fIname\fP [\fIname\fP ...]
+With no options,
+indicate how each
+.I name
+would be interpreted if used as a command name.
+If the
+.B \-t
+option is used,
+.B type
+prints a string which is one of
+.IR alias ,
+.IR keyword ,
+.IR function ,
+.IR builtin ,
+or
+.I file
+if
+.I name
+is an alias, shell reserved word, function, builtin, or disk file,
+respectively.
+If the
+.I name
+is not found, then nothing is printed, and an exit status of false
+is returned.
+If the
+.B \-p
+option is used,
+.B type
+either returns the name of the disk file
+that would be executed if
+.I name
+were specified as a command name,
+or nothing if
+.if t \f(CWtype -t name\fP
+.if n ``type -t name''
+would not return
+.IR file .
+The
+.B \-P
+option forces a
+.SM
+.B PATH
+search for each \fIname\fP, even if
+.if t \f(CWtype -t name\fP
+.if n ``type -t name''
+would not return
+.IR file .
+If a command is hashed,
+.B \-p
+and
+.B \-P
+print the hashed value, which is not necessarily the file that appears
+first in
+.SM
+.BR PATH .
+If the
+.B \-a
+option is used,
+.B type
+prints all of the places that contain
+an executable named
+.IR name .
+This includes aliases and functions,
+if and only if the
+.B \-p
+option is not also used.
+The table of hashed commands is not consulted
+when using
+.BR \-a .
+The
+.B \-f
+option suppresses shell function lookup, as with the \fBcommand\fP builtin.
+.B type
+returns true if all of the arguments are found, false if
+any are not found.
+.TP
+\fBulimit\fP [\fB\-HSabcdefiklmnpqrstuvxPT\fP [\fIlimit\fP]]
+Provides control over the resources available to the shell and to
+processes started by it, on systems that allow such control.
+The \fB\-H\fP and \fB\-S\fP options specify that the hard or soft limit is
+set for the given resource.
+A hard limit cannot be increased by a non-root user once it is set;
+a soft limit may be increased up to the value of the hard limit.
+If neither \fB\-H\fP nor \fB\-S\fP is specified, both the soft and hard
+limits are set.
+The value of
+.I limit
+can be a number in the unit specified for the resource
+or one of the special values
+.BR hard ,
+.BR soft ,
+or
+.BR unlimited ,
+which stand for the current hard limit, the current soft limit, and
+no limit, respectively.
+If
+.I limit
+is omitted, the current value of the soft limit of the resource is
+printed, unless the \fB\-H\fP option is given. When more than one
+resource is specified, the limit name and unit are printed before the value.
+Other options are interpreted as follows:
+.RS
+.PD 0
+.TP
+.B \-a
+All current limits are reported
+.TP
+.B \-b
+The maximum socket buffer size
+.TP
+.B \-c
+The maximum size of core files created
+.TP
+.B \-d
+The maximum size of a process's data segment
+.TP
+.B \-e
+The maximum scheduling priority ("nice")
+.TP
+.B \-f
+The maximum size of files written by the shell and its children
+.TP
+.B \-i
+The maximum number of pending signals
+.TP
+.B \-k
+The maximum number of kqueues that may be allocated
+.TP
+.B \-l
+The maximum size that may be locked into memory
+.TP
+.B \-m
+The maximum resident set size (many systems do not honor this limit)
+.TP
+.B \-n
+The maximum number of open file descriptors (most systems do not
+allow this value to be set)
+.TP
+.B \-p
+The pipe size in 512-byte blocks (this may not be set)
+.TP
+.B \-q
+The maximum number of bytes in POSIX message queues
+.TP
+.B \-r
+The maximum real-time scheduling priority
+.TP
+.B \-s
+The maximum stack size
+.TP
+.B \-t
+The maximum amount of cpu time in seconds
+.TP
+.B \-u
+The maximum number of processes available to a single user
+.TP
+.B \-v
+The maximum amount of virtual memory available to the shell and, on
+some systems, to its children
+.TP
+.B \-x
+The maximum number of file locks
+.TP
+.B \-P
+The maximum number of pseudoterminals
+.TP
+.B \-T
+The maximum number of threads
+.PD
+.PP
+If
+.I limit
+is given, and the
+.B \-a
+option is not used,
+\fIlimit\fP is the new value of the specified resource.
+If no option is given, then
+.B \-f
+is assumed. Values are in 1024-byte increments, except for
+.BR \-t ,
+which is in seconds;
+.BR \-p ,
+which is in units of 512-byte blocks;
+and
+.BR \-P ,
+.BR \-T ,
+.BR \-b ,
+.BR \-k ,
+.BR \-n ,
+and
+.BR \-u ,
+which are unscaled values.
+The return status is 0 unless an invalid option or argument is supplied,
+or an error occurs while setting a new limit.
+.RE
+.TP
+\fBumask\fP [\fB\-p\fP] [\fB\-S\fP] [\fImode\fP]
+The user file-creation mask is set to
+.IR mode .
+If
+.I mode
+begins with a digit, it
+is interpreted as an octal number; otherwise
+it is interpreted as a symbolic mode mask similar
+to that accepted by
+.IR chmod (1).
+If
+.I mode
+is omitted, the current value of the mask is printed.
+The
+.B \-S
+option causes the mask to be printed in symbolic form; the
+default output is an octal number.
+If the
+.B \-p
+option is supplied, and
+.I mode
+is omitted, the output is in a form that may be reused as input.
+The return status is 0 if the mode was successfully changed or if
+no \fImode\fP argument was supplied, and false otherwise.
+.TP
+\fBunalias\fP [\-\fBa\fP] [\fIname\fP ...]
+Remove each \fIname\fP from the list of defined aliases. If
+.B \-a
+is supplied, all alias definitions are removed. The return
+value is true unless a supplied
+.I name
+is not a defined alias.
+.TP
+\fBunset\fP [\-\fBfv\fP] [\-\fBn\fP] [\fIname\fP ...]
+For each
+.IR name ,
+remove the corresponding variable or function.
+If the
+.B \-v
+option is given, each
+.I name
+refers to a shell variable, and that variable is removed.
+Read-only variables may not be unset.
+If
+.B \-f
+is specified, each
+.I name
+refers to a shell function, and the function definition
+is removed.
+If the
+.B \-n
+option is supplied, and \fIname\fP is a variable with the \fInameref\fP
+attribute, \fIname\fP will be unset rather than the variable it
+references.
+\fB\-n\fP has no effect if the \fB\-f\fP option is supplied.
+If no options are supplied, each \fIname\fP refers to a variable; if
+there is no variable by that name, any function with that name is
+unset.
+Each unset variable or function is removed from the environment
+passed to subsequent commands.
+If any of
+.SM
+.BR COMP_WORDBREAKS ,
+.SM
+.BR RANDOM ,
+.SM
+.BR SECONDS ,
+.SM
+.BR LINENO ,
+.SM
+.BR HISTCMD ,
+.SM
+.BR FUNCNAME ,
+.SM
+.BR GROUPS ,
+or
+.SM
+.B DIRSTACK
+are unset, they lose their special properties, even if they are
+subsequently reset. The exit status is true unless a
+.I name
+is readonly.
+.TP
+\fBwait\fP [\fB\-n\fP] [\fIn ...\fP]
+Wait for each specified child process and return its termination status.
+Each
+.I n
+may be a process
+ID or a job specification; if a job spec is given, all processes
+in that job's pipeline are waited for. If
+.I n
+is not given, all currently active child processes
+are waited for, and the return status is zero.
+If the \fB\-n\fP option is supplied, \fBwait\fP waits for any job to
+terminate and returns its exit status.
+If
+.I n
+specifies a non-existent process or job, the return status is
+127. Otherwise, the return status is the exit status of the last
+process or job waited for.
+.\" bash_builtins
+.if \n(zZ=1 .ig zZ
+.SH "RESTRICTED SHELL"
+.\" rbash.1
+.zY
+.PP
+If
+.B bash
+is started with the name
+.BR rbash ,
+or the
+.B \-r
+option is supplied at invocation,
+the shell becomes restricted.
+A restricted shell is used to
+set up an environment more controlled than the standard shell.
+It behaves identically to
+.B bash
+with the exception that the following are disallowed or not performed:
+.IP \(bu
+changing directories with \fBcd\fP
+.IP \(bu
+setting or unsetting the values of
+.SM
+.BR SHELL ,
+.SM
+.BR PATH ,
+.SM
+.BR ENV ,
+or
+.SM
+.B BASH_ENV
+.IP \(bu
+specifying command names containing
+.B /
+.IP \(bu
+specifying a filename containing a
+.B /
+as an argument to the
+.B .
+builtin command
+.IP \(bu
+specifying a filename containing a slash as an argument to the
+.B \-p
+option to the
+.B hash
+builtin command
+.IP \(bu
+importing function definitions from the shell environment at startup
+.IP \(bu
+parsing the value of
+.SM
+.B SHELLOPTS
+from the shell environment at startup
+.IP \(bu
+redirecting output using the >, >|, <>, >&, &>, and >> redirection operators
+.IP \(bu
+using the
+.B exec
+builtin command to replace the shell with another command
+.IP \(bu
+adding or deleting builtin commands with the
+.B \-f
+and
+.B \-d
+options to the
+.B enable
+builtin command
+.IP \(bu
+using the \fBenable\fP builtin command to enable disabled shell builtins
+.IP \(bu
+specifying the
+.B \-p
+option to the
+.B command
+builtin command
+.IP \(bu
+turning off restricted mode with
+\fBset +r\fP or \fBset +o restricted\fP.
+.PP
+These restrictions are enforced after any startup files are read.
+.PP
+.ie \n(zY=1 When a command that is found to be a shell script is executed,
+.el \{ When a command that is found to be a shell script is executed
+(see
+.SM
+.B "COMMAND EXECUTION"
+above),
+\}
+.B rbash
+turns off any restrictions in the shell spawned to execute the
+script.
+.\" end of rbash.1
+.if \n(zY=1 .ig zY
+.SH "SEE ALSO"
+.PD 0
+.TP
+\fIBash Reference Manual\fP, Brian Fox and Chet Ramey
+.TP
+\fIThe Gnu Readline Library\fP, Brian Fox and Chet Ramey
+.TP
+\fIThe Gnu History Library\fP, Brian Fox and Chet Ramey
+.TP
+\fIPortable Operating System Interface (POSIX) Part 2: Shell and Utilities\fP, IEEE --
+http://pubs.opengroup.org/onlinepubs/9699919799/
+.TP
+http://tiswww.case.edu/~chet/bash/POSIX -- a description of posix mode
+.TP
+\fIsh\fP(1), \fIksh\fP(1), \fIcsh\fP(1)
+.TP
+\fIemacs\fP(1), \fIvi\fP(1)
+.TP
+\fIreadline\fP(3)
+.PD
+.SH FILES
+.PD 0
+.TP
+.FN /bin/bash
+The \fBbash\fP executable
+.TP
+.FN /etc/profile
+The systemwide initialization file, executed for login shells
+.TP
+.FN ~/.bash_profile
+The personal initialization file, executed for login shells
+.TP
+.FN ~/.bashrc
+The individual per-interactive-shell startup file
+.TP
+.FN ~/.bash_logout
+The individual login shell cleanup file, executed when a login shell exits
+.TP
+.FN ~/.inputrc
+Individual \fIreadline\fP initialization file
+.PD
+.SH AUTHORS
+Brian Fox, Free Software Foundation
+.br
+bfox@gnu.org
+.PP
+Chet Ramey, Case Western Reserve University
+.br
+chet.ramey@case.edu
+.SH BUG REPORTS
+If you find a bug in
+.B bash,
+you should report it. But first, you should
+make sure that it really is a bug, and that it appears in the latest
+version of
+.BR bash .
+The latest version is always available from
+\fIftp://ftp.gnu.org/pub/gnu/bash/\fP.
+.PP
+Once you have determined that a bug actually exists, use the
+.I bashbug
+command to submit a bug report.
+If you have a fix, you are encouraged to mail that as well!
+Suggestions and `philosophical' bug reports may be mailed
+to \fIbug-bash@gnu.org\fP or posted to the Usenet
+newsgroup
+.BR gnu.bash.bug .
+.PP
+ALL bug reports should include:
+.PP
+.PD 0
+.TP 20
+The version number of \fBbash\fR
+.TP
+The hardware and operating system
+.TP
+The compiler used to compile
+.TP
+A description of the bug behaviour
+.TP
+A short script or `recipe' which exercises the bug
+.PD
+.PP
+.I bashbug
+inserts the first three items automatically into the template
+it provides for filing a bug report.
+.PP
+Comments and bug reports concerning
+this manual page should be directed to
+.IR chet.ramey@case.edu .
+.SH BUGS
+.PP
+It's too big and too slow.
+.PP
+There are some subtle differences between
+.B bash
+and traditional versions of
+.BR sh ,
+mostly because of the
+.SM
+.B POSIX
+specification.
+.PP
+Aliases are confusing in some uses.
+.PP
+Shell builtin commands and functions are not stoppable/restartable.
+.PP
+Compound commands and command sequences of the form `a ; b ; c'
+are not handled gracefully when process suspension is attempted.
+When a process is stopped, the shell immediately executes the next
+command in the sequence.
+It suffices to place the sequence of commands between
+parentheses to force it into a subshell, which may be stopped as
+a unit.
+.PP
+Array variables may not (yet) be exported.
+.PP
+There may be only one active coprocess at a time.
+.zZ
+.zY
interpreted as part of its name.
If the first character of @var{parameter} is an exclamation point (!),
+and @var{parameter} is not a @var{nameref},
it introduces a level of variable indirection.
Bash uses the value of the variable formed from the rest of
@var{parameter} as the name of the variable; this variable is then
expanded and that value is used in the rest of the substitution, rather
than the value of @var{parameter} itself.
This is known as @code{indirect expansion}.
+If @var{parameter} is a nameref, this expands to the name of the
+variable referenced by @var{parameter} instead of performing the
+complete indirect expansion.
The exceptions to this are the expansions of $@{!@var{prefix}*@}
and $@{!@var{name}[@@]@}
described below.
--- /dev/null
+\input texinfo.tex @c -*- texinfo -*-
+@c %**start of header
+@setfilename bashref.info
+@settitle Bash Reference Manual
+
+@include version.texi
+@c %**end of header
+
+@copying
+This text is a brief description of the features that are present in
+the Bash shell (version @value{VERSION}, @value{UPDATED}).
+
+This is Edition @value{EDITION}, last updated @value{UPDATED},
+of @cite{The GNU Bash Reference Manual},
+for @code{Bash}, Version @value{VERSION}.
+
+Copyright @copyright{} 1988--2014 Free Software Foundation, Inc.
+
+@quotation
+Permission is granted to copy, distribute and/or modify this document
+under the terms of the GNU Free Documentation License, Version 1.3 or
+any later version published by the Free Software Foundation; with no
+Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts.
+A copy of the license is included in the section entitled
+``GNU Free Documentation License''.
+@end quotation
+@end copying
+
+@defcodeindex bt
+@defcodeindex rw
+@set BashFeatures
+
+@dircategory Basics
+@direntry
+* Bash: (bash). The GNU Bourne-Again SHell.
+@end direntry
+
+@finalout
+
+@titlepage
+@title Bash Reference Manual
+@subtitle Reference Documentation for Bash
+@subtitle Edition @value{EDITION}, for @code{Bash} Version @value{VERSION}.
+@subtitle @value{UPDATED-MONTH}
+@author Chet Ramey, Case Western Reserve University
+@author Brian Fox, Free Software Foundation
+
+@page
+@vskip 0pt plus 1filll
+@insertcopying
+
+@end titlepage
+
+@contents
+
+@ifnottex
+@node Top, Introduction, (dir), (dir)
+@top Bash Features
+
+This text is a brief description of the features that are present in
+the Bash shell (version @value{VERSION}, @value{UPDATED}).
+The Bash home page is @url{http://www.gnu.org/software/bash/}.
+
+This is Edition @value{EDITION}, last updated @value{UPDATED},
+of @cite{The GNU Bash Reference Manual},
+for @code{Bash}, Version @value{VERSION}.
+
+Bash contains features that appear in other popular shells, and some
+features that only appear in Bash. Some of the shells that Bash has
+borrowed concepts from are the Bourne Shell (@file{sh}), the Korn Shell
+(@file{ksh}), and the C-shell (@file{csh} and its successor,
+@file{tcsh}). The following menu breaks the features up into
+categories, noting which features were inspired by other shells and
+which are specific to Bash.
+
+This manual is meant as a brief introduction to features found in
+Bash. The Bash manual page should be used as the definitive
+reference on shell behavior.
+
+@menu
+* Introduction:: An introduction to the shell.
+* Definitions:: Some definitions used in the rest of this
+ manual.
+* Basic Shell Features:: The shell "building blocks".
+* Shell Builtin Commands:: Commands that are a part of the shell.
+* Shell Variables:: Variables used or set by Bash.
+* Bash Features:: Features found only in Bash.
+* Job Control:: What job control is and how Bash allows you
+ to use it.
+* Command Line Editing:: Chapter describing the command line
+ editing features.
+* Using History Interactively:: Command History Expansion
+* Installing Bash:: How to build and install Bash on your system.
+* Reporting Bugs:: How to report bugs in Bash.
+* Major Differences From The Bourne Shell:: A terse list of the differences
+ between Bash and historical
+ versions of /bin/sh.
+* GNU Free Documentation License:: Copying and sharing this documentation.
+* Indexes:: Various indexes for this manual.
+@end menu
+@end ifnottex
+
+@node Introduction
+@chapter Introduction
+@menu
+* What is Bash?:: A short description of Bash.
+* What is a shell?:: A brief introduction to shells.
+@end menu
+
+@node What is Bash?
+@section What is Bash?
+
+Bash is the shell, or command language interpreter,
+for the @sc{gnu} operating system.
+The name is an acronym for the @samp{Bourne-Again SHell},
+a pun on Stephen Bourne, the author of the direct ancestor of
+the current Unix shell @code{sh},
+which appeared in the Seventh Edition Bell Labs Research version
+of Unix.
+
+Bash is largely compatible with @code{sh} and incorporates useful
+features from the Korn shell @code{ksh} and the C shell @code{csh}.
+It is intended to be a conformant implementation of the @sc{ieee}
+@sc{posix} Shell and Tools portion of the @sc{ieee} @sc{posix}
+specification (@sc{ieee} Standard 1003.1).
+It offers functional improvements over @code{sh} for both interactive and
+programming use.
+
+While the @sc{gnu} operating system provides other shells, including
+a version of @code{csh}, Bash is the default shell.
+Like other @sc{gnu} software, Bash is quite portable. It currently runs
+on nearly every version of Unix and a few other operating systems @minus{}
+independently-supported ports exist for @sc{ms-dos}, @sc{os/2},
+and Windows platforms.
+
+@node What is a shell?
+@section What is a shell?
+
+At its base, a shell is simply a macro processor that executes
+commands. The term macro processor means functionality where text
+and symbols are expanded to create larger expressions.
+
+A Unix shell is both a command interpreter and a programming
+language. As a command interpreter, the shell provides the user
+interface to the rich set of @sc{gnu} utilities. The programming
+language features allow these utilities to be combined.
+Files containing commands can be created, and become
+commands themselves. These new commands have the same status as
+system commands in directories such as @file{/bin}, allowing users
+or groups to establish custom environments to automate their common
+tasks.
+
+Shells may be used interactively or non-interactively. In
+interactive mode, they accept input typed from the keyboard.
+When executing non-interactively, shells execute commands read
+from a file.
+
+A shell allows execution of @sc{gnu} commands, both synchronously and
+asynchronously.
+The shell waits for synchronous commands to complete before accepting
+more input; asynchronous commands continue to execute in parallel
+with the shell while it reads and executes additional commands.
+The @dfn{redirection} constructs permit
+fine-grained control of the input and output of those commands.
+Moreover, the shell allows control over the contents of commands'
+environments.
+
+Shells also provide a small set of built-in
+commands (@dfn{builtins}) implementing functionality impossible
+or inconvenient to obtain via separate utilities.
+For example, @code{cd}, @code{break}, @code{continue}, and
+@code{exec} cannot be implemented outside of the shell because
+they directly manipulate the shell itself.
+The @code{history}, @code{getopts}, @code{kill}, or @code{pwd}
+builtins, among others, could be implemented in separate utilities,
+but they are more convenient to use as builtin commands.
+All of the shell builtins are described in
+subsequent sections.
+
+While executing commands is essential, most of the power (and
+complexity) of shells is due to their embedded programming
+languages. Like any high-level language, the shell provides
+variables, flow control constructs, quoting, and functions.
+
+Shells offer features geared specifically for
+interactive use rather than to augment the programming language.
+These interactive features include job control, command line
+editing, command history and aliases. Each of these features is
+described in this manual.
+
+@node Definitions
+@chapter Definitions
+These definitions are used throughout the remainder of this manual.
+
+@table @code
+
+@item POSIX
+@cindex POSIX
+A family of open system standards based on Unix. Bash
+is primarily concerned with the Shell and Utilities portion of the
+@sc{posix} 1003.1 standard.
+
+@item blank
+A space or tab character.
+
+@item builtin
+@cindex builtin
+A command that is implemented internally by the shell itself, rather
+than by an executable program somewhere in the file system.
+
+@item control operator
+@cindex control operator
+A @code{token} that performs a control function. It is a @code{newline}
+or one of the following:
+@samp{||}, @samp{&&}, @samp{&}, @samp{;}, @samp{;;},
+@samp{|}, @samp{|&}, @samp{(}, or @samp{)}.
+
+@item exit status
+@cindex exit status
+The value returned by a command to its caller. The value is restricted
+to eight bits, so the maximum value is 255.
+
+@item field
+@cindex field
+A unit of text that is the result of one of the shell expansions. After
+expansion, when executing a command, the resulting fields are used as
+the command name and arguments.
+
+@item filename
+@cindex filename
+A string of characters used to identify a file.
+
+@item job
+@cindex job
+A set of processes comprising a pipeline, and any processes descended
+from it, that are all in the same process group.
+
+@item job control
+@cindex job control
+A mechanism by which users can selectively stop (suspend) and restart
+(resume) execution of processes.
+
+@item metacharacter
+@cindex metacharacter
+A character that, when unquoted, separates words. A metacharacter is
+a @code{blank} or one of the following characters:
+@samp{|}, @samp{&}, @samp{;}, @samp{(}, @samp{)}, @samp{<}, or
+@samp{>}.
+
+@item name
+@cindex name
+@cindex identifier
+A @code{word} consisting solely of letters, numbers, and underscores,
+and beginning with a letter or underscore. @code{Name}s are used as
+shell variable and function names.
+Also referred to as an @code{identifier}.
+
+@item operator
+@cindex operator, shell
+A @code{control operator} or a @code{redirection operator}.
+@xref{Redirections}, for a list of redirection operators.
+Operators contain at least one unquoted @code{metacharacter}.
+
+@item process group
+@cindex process group
+A collection of related processes each having the same process
+group @sc{id}.
+
+@item process group ID
+@cindex process group ID
+A unique identifier that represents a @code{process group}
+during its lifetime.
+
+@item reserved word
+@cindex reserved word
+A @code{word} that has a special meaning to the shell. Most reserved
+words introduce shell flow control constructs, such as @code{for} and
+@code{while}.
+
+@item return status
+@cindex return status
+A synonym for @code{exit status}.
+
+@item signal
+@cindex signal
+A mechanism by which a process may be notified by the kernel
+of an event occurring in the system.
+
+@item special builtin
+@cindex special builtin
+A shell builtin command that has been classified as special by the
+@sc{posix} standard.
+
+@item token
+@cindex token
+A sequence of characters considered a single unit by the shell.
+It is either a @code{word} or an @code{operator}.
+
+@item word
+@cindex word
+A sequence of characters treated as a unit by the shell.
+Words may not include unquoted @code{metacharacters}.
+@end table
+
+@node Basic Shell Features
+@chapter Basic Shell Features
+@cindex Bourne shell
+
+Bash is an acronym for @samp{Bourne-Again SHell}.
+The Bourne shell is
+the traditional Unix shell originally written by Stephen Bourne.
+All of the Bourne shell builtin commands are available in Bash,
+The rules for evaluation and quoting are taken from the @sc{posix}
+specification for the `standard' Unix shell.
+
+This chapter briefly summarizes the shell's `building blocks':
+commands, control structures, shell functions, shell @i{parameters},
+shell expansions,
+@i{redirections}, which are a way to direct input and output from
+and to named files, and how the shell executes commands.
+
+@menu
+* Shell Syntax:: What your input means to the shell.
+* Shell Commands:: The types of commands you can use.
+* Shell Functions:: Grouping commands by name.
+* Shell Parameters:: How the shell stores values.
+* Shell Expansions:: How Bash expands parameters and the various
+ expansions available.
+* Redirections:: A way to control where input and output go.
+* Executing Commands:: What happens when you run a command.
+* Shell Scripts:: Executing files of shell commands.
+@end menu
+
+@node Shell Syntax
+@section Shell Syntax
+@menu
+* Shell Operation:: The basic operation of the shell.
+* Quoting:: How to remove the special meaning from characters.
+* Comments:: How to specify comments.
+@end menu
+
+When the shell reads input, it proceeds through a
+sequence of operations. If the input indicates the beginning of a
+comment, the shell ignores the comment symbol (@samp{#}), and the rest
+of that line.
+
+Otherwise, roughly speaking, the shell reads its input and
+divides the input into words and operators, employing the quoting rules
+to select which meanings to assign various words and characters.
+
+The shell then parses these tokens into commands and other constructs,
+removes the special meaning of certain words or characters, expands
+others, redirects input and output as needed, executes the specified
+command, waits for the command's exit status, and makes that exit status
+available for further inspection or processing.
+
+@node Shell Operation
+@subsection Shell Operation
+
+The following is a brief description of the shell's operation when it
+reads and executes a command. Basically, the shell does the
+following:
+
+@enumerate
+@item
+Reads its input from a file (@pxref{Shell Scripts}), from a string
+supplied as an argument to the @option{-c} invocation option
+(@pxref{Invoking Bash}), or from the user's terminal.
+
+@item
+Breaks the input into words and operators, obeying the quoting rules
+described in @ref{Quoting}. These tokens are separated by
+@code{metacharacters}. Alias expansion is performed by this step
+(@pxref{Aliases}).
+
+@item
+Parses the tokens into simple and compound commands
+(@pxref{Shell Commands}).
+
+@item
+Performs the various shell expansions (@pxref{Shell Expansions}), breaking
+the expanded tokens into lists of filenames (@pxref{Filename Expansion})
+and commands and arguments.
+
+@item
+Performs any necessary redirections (@pxref{Redirections}) and removes
+the redirection operators and their operands from the argument list.
+
+@item
+Executes the command (@pxref{Executing Commands}).
+
+@item
+Optionally waits for the command to complete and collects its exit
+status (@pxref{Exit Status}).
+
+@end enumerate
+
+@node Quoting
+@subsection Quoting
+@cindex quoting
+@menu
+* Escape Character:: How to remove the special meaning from a single
+ character.
+* Single Quotes:: How to inhibit all interpretation of a sequence
+ of characters.
+* Double Quotes:: How to suppress most of the interpretation of a
+ sequence of characters.
+* ANSI-C Quoting:: How to expand ANSI-C sequences in quoted strings.
+* Locale Translation:: How to translate strings into different languages.
+@end menu
+
+Quoting is used to remove the special meaning of certain
+characters or words to the shell. Quoting can be used to
+disable special treatment for special characters, to prevent
+reserved words from being recognized as such, and to prevent
+parameter expansion.
+
+Each of the shell metacharacters (@pxref{Definitions})
+has special meaning to the shell and must be quoted if it is to
+represent itself.
+When the command history expansion facilities are being used
+(@pxref{History Interaction}), the
+@var{history expansion} character, usually @samp{!}, must be quoted
+to prevent history expansion. @xref{Bash History Facilities}, for
+more details concerning history expansion.
+
+There are three quoting mechanisms: the
+@var{escape character}, single quotes, and double quotes.
+
+@node Escape Character
+@subsubsection Escape Character
+A non-quoted backslash @samp{\} is the Bash escape character.
+It preserves the literal value of the next character that follows,
+with the exception of @code{newline}. If a @code{\newline} pair
+appears, and the backslash itself is not quoted, the @code{\newline}
+is treated as a line continuation (that is, it is removed from
+the input stream and effectively ignored).
+
+@node Single Quotes
+@subsubsection Single Quotes
+
+Enclosing characters in single quotes (@samp{'}) preserves the literal value
+of each character within the quotes. A single quote may not occur
+between single quotes, even when preceded by a backslash.
+
+@node Double Quotes
+@subsubsection Double Quotes
+
+Enclosing characters in double quotes (@samp{"}) preserves the literal value
+of all characters within the quotes, with the exception of
+@samp{$}, @samp{`}, @samp{\},
+and, when history expansion is enabled, @samp{!}.
+The characters @samp{$} and @samp{`}
+retain their special meaning within double quotes (@pxref{Shell Expansions}).
+The backslash retains its special meaning only when followed by one of
+the following characters:
+@samp{$}, @samp{`}, @samp{"}, @samp{\}, or @code{newline}.
+Within double quotes, backslashes that are followed by one of these
+characters are removed. Backslashes preceding characters without a
+special meaning are left unmodified.
+A double quote may be quoted within double quotes by preceding it with
+a backslash.
+If enabled, history expansion will be performed unless an @samp{!}
+appearing in double quotes is escaped using a backslash.
+The backslash preceding the @samp{!} is not removed.
+
+The special parameters @samp{*} and @samp{@@} have special meaning
+when in double quotes (@pxref{Shell Parameter Expansion}).
+
+@node ANSI-C Quoting
+@subsubsection ANSI-C Quoting
+@cindex quoting, ANSI
+
+Words of the form @code{$'@var{string}'} are treated specially. The
+word expands to @var{string}, with backslash-escaped characters replaced
+as specified by the ANSI C standard. Backslash escape sequences, if
+present, are decoded as follows:
+
+@table @code
+@item \a
+alert (bell)
+@item \b
+backspace
+@item \e
+@itemx \E
+an escape character (not ANSI C)
+@item \f
+form feed
+@item \n
+newline
+@item \r
+carriage return
+@item \t
+horizontal tab
+@item \v
+vertical tab
+@item \\
+backslash
+@item \'
+single quote
+@item \"
+double quote
+@item \@var{nnn}
+the eight-bit character whose value is the octal value @var{nnn}
+(one to three digits)
+@item \x@var{HH}
+the eight-bit character whose value is the hexadecimal value @var{HH}
+(one or two hex digits)
+@item \u@var{HHHH}
+the Unicode (ISO/IEC 10646) character whose value is the hexadecimal value
+@var{HHHH} (one to four hex digits)
+@item \U@var{HHHHHHHH}
+the Unicode (ISO/IEC 10646) character whose value is the hexadecimal value
+@var{HHHHHHHH} (one to eight hex digits)
+@item \c@var{x}
+a control-@var{x} character
+@end table
+
+@noindent
+The expanded result is single-quoted, as if the dollar sign had not
+been present.
+
+@node Locale Translation
+@subsubsection Locale-Specific Translation
+@cindex localization
+@cindex internationalization
+@cindex native languages
+@cindex translation, native languages
+
+A double-quoted string preceded by a dollar sign (@samp{$}) will cause
+the string to be translated according to the current locale.
+If the current locale is @code{C} or @code{POSIX}, the dollar sign
+is ignored.
+If the string is translated and replaced, the replacement is
+double-quoted.
+
+@vindex LC_MESSAGES
+@vindex TEXTDOMAIN
+@vindex TEXTDOMAINDIR
+Some systems use the message catalog selected by the @env{LC_MESSAGES}
+shell variable. Others create the name of the message catalog from the
+value of the @env{TEXTDOMAIN} shell variable, possibly adding a
+suffix of @samp{.mo}. If you use the @env{TEXTDOMAIN} variable, you
+may need to set the @env{TEXTDOMAINDIR} variable to the location of
+the message catalog files. Still others use both variables in this
+fashion:
+@env{TEXTDOMAINDIR}/@env{LC_MESSAGES}/LC_MESSAGES/@env{TEXTDOMAIN}.mo.
+
+@node Comments
+@subsection Comments
+@cindex comments, shell
+
+In a non-interactive shell, or an interactive shell in which the
+@code{interactive_comments} option to the @code{shopt}
+builtin is enabled (@pxref{The Shopt Builtin}),
+a word beginning with @samp{#}
+causes that word and all remaining characters on that line to
+be ignored. An interactive shell without the @code{interactive_comments}
+option enabled does not allow comments. The @code{interactive_comments}
+option is on by default in interactive shells.
+@xref{Interactive Shells}, for a description of what makes
+a shell interactive.
+
+@node Shell Commands
+@section Shell Commands
+@cindex commands, shell
+
+A simple shell command such as @code{echo a b c} consists of the command
+itself followed by arguments, separated by spaces.
+
+More complex shell commands are composed of simple commands arranged together
+in a variety of ways: in a pipeline in which the output of one command
+becomes the input of a second, in a loop or conditional construct, or in
+some other grouping.
+
+@menu
+* Simple Commands:: The most common type of command.
+* Pipelines:: Connecting the input and output of several
+ commands.
+* Lists:: How to execute commands sequentially.
+* Compound Commands:: Shell commands for control flow.
+* Coprocesses:: Two-way communication between commands.
+* GNU Parallel:: Running commands in parallel.
+@end menu
+
+@node Simple Commands
+@subsection Simple Commands
+@cindex commands, simple
+
+A simple command is the kind of command encountered most often.
+It's just a sequence of words separated by @code{blank}s, terminated
+by one of the shell's control operators (@pxref{Definitions}). The
+first word generally specifies a command to be executed, with the
+rest of the words being that command's arguments.
+
+The return status (@pxref{Exit Status}) of a simple command is
+its exit status as provided
+by the @sc{posix} 1003.1 @code{waitpid} function, or 128+@var{n} if
+the command was terminated by signal @var{n}.
+
+@node Pipelines
+@subsection Pipelines
+@cindex pipeline
+@cindex commands, pipelines
+
+A @code{pipeline} is a sequence of one or more commands separated by
+one of the control operators @samp{|} or @samp{|&}.
+
+@rwindex time
+@rwindex !
+@cindex command timing
+The format for a pipeline is
+@example
+[time [-p]] [!] @var{command1} [ | or |& @var{command2} ] @dots{}
+@end example
+
+@noindent
+The output of each command in the pipeline is connected via a pipe
+to the input of the next command.
+That is, each command reads the previous command's output. This
+connection is performed before any redirections specified by the
+command.
+
+If @samp{|&} is used, @var{command1}'s standard error, in addition to
+its standard output, is connected to
+@var{command2}'s standard input through the pipe;
+it is shorthand for @code{2>&1 |}.
+This implicit redirection of the standard error to the standard output is
+performed after any redirections specified by the command.
+
+The reserved word @code{time} causes timing statistics
+to be printed for the pipeline once it finishes.
+The statistics currently consist of elapsed (wall-clock) time and
+user and system time consumed by the command's execution.
+The @option{-p} option changes the output format to that specified
+by @sc{posix}.
+When the shell is in @sc{posix} mode (@pxref{Bash POSIX Mode}),
+it does not recognize @code{time} as a reserved word if the next
+token begins with a @samp{-}.
+The @env{TIMEFORMAT} variable may be set to a format string that
+specifies how the timing information should be displayed.
+@xref{Bash Variables}, for a description of the available formats.
+The use of @code{time} as a reserved word permits the timing of
+shell builtins, shell functions, and pipelines. An external
+@code{time} command cannot time these easily.
+
+When the shell is in @sc{posix} mode (@pxref{Bash POSIX Mode}), @code{time}
+may be followed by a newline. In this case, the shell displays the
+total user and system time consumed by the shell and its children.
+The @env{TIMEFORMAT} variable may be used to specify the format of
+the time information.
+
+If the pipeline is not executed asynchronously (@pxref{Lists}), the
+shell waits for all commands in the pipeline to complete.
+
+Each command in a pipeline is executed in its own subshell
+(@pxref{Command Execution Environment}). The exit
+status of a pipeline is the exit status of the last command in the
+pipeline, unless the @code{pipefail} option is enabled
+(@pxref{The Set Builtin}).
+If @code{pipefail} is enabled, the pipeline's return status is the
+value of the last (rightmost) command to exit with a non-zero status,
+or zero if all commands exit successfully.
+If the reserved word @samp{!} precedes the pipeline, the
+exit status is the logical negation of the exit status as described
+above.
+The shell waits for all commands in the pipeline to terminate before
+returning a value.
+
+@node Lists
+@subsection Lists of Commands
+@cindex commands, lists
+
+A @code{list} is a sequence of one or more pipelines separated by one
+of the operators @samp{;}, @samp{&}, @samp{&&}, or @samp{||},
+and optionally terminated by one of @samp{;}, @samp{&}, or a
+@code{newline}.
+
+Of these list operators, @samp{&&} and @samp{||}
+have equal precedence, followed by @samp{;} and @samp{&},
+which have equal precedence.
+
+A sequence of one or more newlines may appear in a @code{list}
+to delimit commands, equivalent to a semicolon.
+
+If a command is terminated by the control operator @samp{&},
+the shell executes the command asynchronously in a subshell.
+This is known as executing the command in the @var{background}.
+The shell does not wait for the command to finish, and the return
+status is 0 (true).
+When job control is not active (@pxref{Job Control}),
+the standard input for asynchronous commands, in the absence of any
+explicit redirections, is redirected from @code{/dev/null}.
+
+Commands separated by a @samp{;} are executed sequentially; the shell
+waits for each command to terminate in turn. The return status is the
+exit status of the last command executed.
+
+@sc{and} and @sc{or} lists are sequences of one or more pipelines
+separated by the control operators @samp{&&} and @samp{||},
+respectively. @sc{and} and @sc{or} lists are executed with left
+associativity.
+
+An @sc{and} list has the form
+@example
+@var{command1} && @var{command2}
+@end example
+
+@noindent
+@var{command2} is executed if, and only if, @var{command1}
+returns an exit status of zero.
+
+An @sc{or} list has the form
+@example
+@var{command1} || @var{command2}
+@end example
+
+@noindent
+@var{command2} is executed if, and only if, @var{command1}
+returns a non-zero exit status.
+
+The return status of
+@sc{and} and @sc{or} lists is the exit status of the last command
+executed in the list.
+
+@node Compound Commands
+@subsection Compound Commands
+@cindex commands, compound
+
+@menu
+* Looping Constructs:: Shell commands for iterative action.
+* Conditional Constructs:: Shell commands for conditional execution.
+* Command Grouping:: Ways to group commands.
+@end menu
+
+Compound commands are the shell programming constructs.
+Each construct begins with a reserved word or control operator and is
+terminated by a corresponding reserved word or operator.
+Any redirections (@pxref{Redirections}) associated with a compound command
+apply to all commands within that compound command unless explicitly overridden.
+
+In most cases a list of commands in a compound command's description may be
+separated from the rest of the command by one or more newlines, and may be
+followed by a newline in place of a semicolon.
+
+Bash provides looping constructs, conditional commands, and mechanisms
+to group commands and execute them as a unit.
+
+@node Looping Constructs
+@subsubsection Looping Constructs
+@cindex commands, looping
+
+Bash supports the following looping constructs.
+
+Note that wherever a @samp{;} appears in the description of a
+command's syntax, it may be replaced with one or more newlines.
+
+@table @code
+@item until
+@rwindex until
+@rwindex do
+@rwindex done
+The syntax of the @code{until} command is:
+
+@example
+until @var{test-commands}; do @var{consequent-commands}; done
+@end example
+
+Execute @var{consequent-commands} as long as
+@var{test-commands} has an exit status which is not zero.
+The return status is the exit status of the last command executed
+in @var{consequent-commands}, or zero if none was executed.
+
+@item while
+@rwindex while
+The syntax of the @code{while} command is:
+
+@example
+while @var{test-commands}; do @var{consequent-commands}; done
+@end example
+
+Execute @var{consequent-commands} as long as
+@var{test-commands} has an exit status of zero.
+The return status is the exit status of the last command executed
+in @var{consequent-commands}, or zero if none was executed.
+
+@item for
+@rwindex for
+The syntax of the @code{for} command is:
+
+@example
+for @var{name} [ [in [@var{words} @dots{}] ] ; ] do @var{commands}; done
+@end example
+
+Expand @var{words}, and execute @var{commands} once for each member
+in the resultant list, with @var{name} bound to the current member.
+If @samp{in @var{words}} is not present, the @code{for} command
+executes the @var{commands} once for each positional parameter that is
+set, as if @samp{in "$@@"} had been specified
+(@pxref{Special Parameters}).
+The return status is the exit status of the last command that executes.
+If there are no items in the expansion of @var{words}, no commands are
+executed, and the return status is zero.
+
+An alternate form of the @code{for} command is also supported:
+
+@example
+for (( @var{expr1} ; @var{expr2} ; @var{expr3} )) ; do @var{commands} ; done
+@end example
+
+First, the arithmetic expression @var{expr1} is evaluated according
+to the rules described below (@pxref{Shell Arithmetic}).
+The arithmetic expression @var{expr2} is then evaluated repeatedly
+until it evaluates to zero.
+Each time @var{expr2} evaluates to a non-zero value, @var{commands} are
+executed and the arithmetic expression @var{expr3} is evaluated.
+If any expression is omitted, it behaves as if it evaluates to 1.
+The return value is the exit status of the last command in @var{commands}
+that is executed, or false if any of the expressions is invalid.
+@end table
+
+The @code{break} and @code{continue} builtins (@pxref{Bourne Shell Builtins})
+may be used to control loop execution.
+
+@node Conditional Constructs
+@subsubsection Conditional Constructs
+@cindex commands, conditional
+
+@table @code
+@item if
+@rwindex if
+@rwindex then
+@rwindex else
+@rwindex elif
+@rwindex fi
+The syntax of the @code{if} command is:
+
+@example
+if @var{test-commands}; then
+ @var{consequent-commands};
+[elif @var{more-test-commands}; then
+ @var{more-consequents};]
+[else @var{alternate-consequents};]
+fi
+@end example
+
+The @var{test-commands} list is executed, and if its return status is zero,
+the @var{consequent-commands} list is executed.
+If @var{test-commands} returns a non-zero status, each @code{elif} list
+is executed in turn, and if its exit status is zero,
+the corresponding @var{more-consequents} is executed and the
+command completes.
+If @samp{else @var{alternate-consequents}} is present, and
+the final command in the final @code{if} or @code{elif} clause
+has a non-zero exit status, then @var{alternate-consequents} is executed.
+The return status is the exit status of the last command executed, or
+zero if no condition tested true.
+
+@item case
+@rwindex case
+@rwindex in
+@rwindex esac
+The syntax of the @code{case} command is:
+
+@example
+case @var{word} in [ [(] @var{pattern} [| @var{pattern}]@dots{}) @var{command-list} ;;]@dots{} esac
+@end example
+
+@code{case} will selectively execute the @var{command-list} corresponding to
+the first @var{pattern} that matches @var{word}.
+If the @code{nocasematch} shell option
+(see the description of @code{shopt} in @ref{The Shopt Builtin})
+is enabled, the match is performed without regard to the case
+of alphabetic characters.
+The @samp{|} is used to separate multiple patterns, and the @samp{)}
+operator terminates a pattern list.
+A list of patterns and an associated command-list is known
+as a @var{clause}.
+
+Each clause must be terminated with @samp{;;}, @samp{;&}, or @samp{;;&}.
+The @var{word} undergoes tilde expansion, parameter expansion, command
+substitution, arithmetic expansion, and quote removal before matching is
+attempted. Each @var{pattern} undergoes tilde expansion, parameter
+expansion, command substitution, and arithmetic expansion.
+
+There may be an arbitrary number of @code{case} clauses, each terminated
+by a @samp{;;}, @samp{;&}, or @samp{;;&}.
+The first pattern that matches determines the
+command-list that is executed.
+It's a common idiom to use @samp{*} as the final pattern to define the
+default case, since that pattern will always match.
+
+Here is an example using @code{case} in a script that could be used to
+describe one interesting feature of an animal:
+
+@example
+echo -n "Enter the name of an animal: "
+read ANIMAL
+echo -n "The $ANIMAL has "
+case $ANIMAL in
+ horse | dog | cat) echo -n "four";;
+ man | kangaroo ) echo -n "two";;
+ *) echo -n "an unknown number of";;
+esac
+echo " legs."
+@end example
+
+@noindent
+
+If the @samp{;;} operator is used, no subsequent matches are attempted after
+the first pattern match.
+Using @samp{;&} in place of @samp{;;} causes execution to continue with
+the @var{command-list} associated with the next clause, if any.
+Using @samp{;;&} in place of @samp{;;} causes the shell to test the patterns
+in the next clause, if any, and execute any associated @var{command-list}
+on a successful match.
+
+The return status is zero if no @var{pattern} is matched. Otherwise, the
+return status is the exit status of the @var{command-list} executed.
+
+@item select
+@rwindex select
+
+The @code{select} construct allows the easy generation of menus.
+It has almost the same syntax as the @code{for} command:
+
+@example
+select @var{name} [in @var{words} @dots{}]; do @var{commands}; done
+@end example
+
+The list of words following @code{in} is expanded, generating a list
+of items. The set of expanded words is printed on the standard
+error output stream, each preceded by a number. If the
+@samp{in @var{words}} is omitted, the positional parameters are printed,
+as if @samp{in "$@@"} had been specified.
+The @env{PS3} prompt is then displayed and a line is read from the
+standard input.
+If the line consists of a number corresponding to one of the displayed
+words, then the value of @var{name} is set to that word.
+If the line is empty, the words and prompt are displayed again.
+If @code{EOF} is read, the @code{select} command completes.
+Any other value read causes @var{name} to be set to null.
+The line read is saved in the variable @env{REPLY}.
+
+The @var{commands} are executed after each selection until a
+@code{break} command is executed, at which
+point the @code{select} command completes.
+
+Here is an example that allows the user to pick a filename from the
+current directory, and displays the name and index of the file
+selected.
+
+@example
+select fname in *;
+do
+ echo you picked $fname \($REPLY\)
+ break;
+done
+@end example
+
+@item ((@dots{}))
+@example
+(( @var{expression} ))
+@end example
+
+The arithmetic @var{expression} is evaluated according to the rules
+described below (@pxref{Shell Arithmetic}).
+If the value of the expression is non-zero, the return status is 0;
+otherwise the return status is 1. This is exactly equivalent to
+@example
+let "@var{expression}"
+@end example
+@noindent
+@xref{Bash Builtins}, for a full description of the @code{let} builtin.
+
+@item [[@dots{}]]
+@rwindex [[
+@rwindex ]]
+@example
+[[ @var{expression} ]]
+@end example
+
+Return a status of 0 or 1 depending on the evaluation of
+the conditional expression @var{expression}.
+Expressions are composed of the primaries described below in
+@ref{Bash Conditional Expressions}.
+Word splitting and filename expansion are not performed on the words
+between the @code{[[} and @code{]]}; tilde expansion, parameter and
+variable expansion, arithmetic expansion, command substitution, process
+substitution, and quote removal are performed.
+Conditional operators such as @samp{-f} must be unquoted to be recognized
+as primaries.
+
+When used with @code{[[}, the @samp{<} and @samp{>} operators sort
+lexicographically using the current locale.
+
+When the @samp{==} and @samp{!=} operators are used, the string to the
+right of the operator is considered a pattern and matched according
+to the rules described below in @ref{Pattern Matching},
+as if the @code{extglob} shell option were enabled.
+The @samp{=} operator is identical to @samp{==}.
+If the @code{nocasematch} shell option
+(see the description of @code{shopt} in @ref{The Shopt Builtin})
+is enabled, the match is performed without regard to the case
+of alphabetic characters.
+The return value is 0 if the string matches (@samp{==}) or does not
+match (@samp{!=})the pattern, and 1 otherwise.
+Any part of the pattern may be quoted to force the quoted portion
+to be matched as a string.
+
+An additional binary operator, @samp{=~}, is available, with the same
+precedence as @samp{==} and @samp{!=}.
+When it is used, the string to the right of the operator is considered
+an extended regular expression and matched accordingly (as in @i{regex}3)).
+The return value is 0 if the string matches
+the pattern, and 1 otherwise.
+If the regular expression is syntactically incorrect, the conditional
+expression's return value is 2.
+If the @code{nocasematch} shell option
+(see the description of @code{shopt} in @ref{The Shopt Builtin})
+is enabled, the match is performed without regard to the case
+of alphabetic characters.
+Any part of the pattern may be quoted to force the quoted portion
+to be matched as a string.
+Bracket expressions in regular expressions must be treated carefully,
+since normal quoting characters lose their meanings between brackets.
+If the pattern is stored in a shell variable, quoting the variable
+expansion forces the entire pattern to be matched as a string.
+Substrings matched by parenthesized subexpressions within the regular
+expression are saved in the array variable @code{BASH_REMATCH}.
+The element of @code{BASH_REMATCH} with index 0 is the portion of the string
+matching the entire regular expression.
+The element of @code{BASH_REMATCH} with index @var{n} is the portion of the
+string matching the @var{n}th parenthesized subexpression.
+
+For example, the following will match a line
+(stored in the shell variable @var{line})
+if there is a sequence of characters in the value consisting of
+any number, including zero, of
+space characters, zero or one instances of @samp{a}, then a @samp{b}:
+@example
+[[ $line =~ [[:space:]]*(a)?b ]]
+@end example
+
+@noindent
+That means values like @samp{aab} and @samp{ aaaaaab} will match, as
+will a line containing a @samp{b} anywhere in its value.
+
+Storing the regular expression in a shell variable is often a useful
+way to avoid problems with quoting characters that are special to the
+shell.
+It is sometimes difficult to specify a regular expression literally
+without using quotes, or to keep track of the quoting used by regular
+expressions while paying attention to the shell's quote removal.
+Using a shell variable to store the pattern decreases these problems.
+For example, the following is equivalent to the above:
+@example
+pattern='[[:space:]]*(a)?b'
+[[ $line =~ $pattern ]]
+@end example
+
+@noindent
+If you want to match a character that's special to the regular expression
+grammar, it has to be quoted to remove its special meaning.
+This means that in the pattern @samp{xxx.txt}, the @samp{.} matches any
+character in the string (its usual regular expression meaning), but in the
+pattern @samp{"xxx.txt"} it can only match a literal @samp{.}.
+Shell programmers should take special care with backslashes, since backslashes
+are used both by the shell and regular expressions to remove the special
+meaning from the following character.
+The following two sets of commands are @emph{not} equivalent:
+@example
+pattern='\.'
+
+[[ . =~ $pattern ]]
+[[ . =~ \. ]]
+
+[[ . =~ "$pattern" ]]
+[[ . =~ '\.' ]]
+@end example
+
+@noindent
+The first two matches will succeed, but the second two will not, because
+in the second two the backslash will be part of the pattern to be matched.
+In the first two examples, the backslash removes the special meaning from
+@samp{.}, so the literal @samp{.} matches.
+If the string in the first examples were anything other than @samp{.}, say
+@samp{a}, the pattern would not match, because the quoted @samp{.} in the
+pattern loses its special meaning of matching any single character.
+
+Expressions may be combined using the following operators, listed
+in decreasing order of precedence:
+
+@table @code
+@item ( @var{expression} )
+Returns the value of @var{expression}.
+This may be used to override the normal precedence of operators.
+
+@item ! @var{expression}
+True if @var{expression} is false.
+
+@item @var{expression1} && @var{expression2}
+True if both @var{expression1} and @var{expression2} are true.
+
+@item @var{expression1} || @var{expression2}
+True if either @var{expression1} or @var{expression2} is true.
+@end table
+
+@noindent
+The @code{&&} and @code{||} operators do not evaluate @var{expression2} if the
+value of @var{expression1} is sufficient to determine the return
+value of the entire conditional expression.
+@end table
+
+@node Command Grouping
+@subsubsection Grouping Commands
+@cindex commands, grouping
+
+Bash provides two ways to group a list of commands to be executed
+as a unit. When commands are grouped, redirections may be applied
+to the entire command list. For example, the output of all the
+commands in the list may be redirected to a single stream.
+
+@table @code
+@item ()
+@example
+( @var{list} )
+@end example
+
+Placing a list of commands between parentheses causes a subshell
+environment to be created (@pxref{Command Execution Environment}), and each
+of the commands in @var{list} to be executed in that subshell. Since the
+@var{list} is executed in a subshell, variable assignments do not remain in
+effect after the subshell completes.
+
+@item @{@}
+@rwindex @{
+@rwindex @}
+@example
+@{ @var{list}; @}
+@end example
+
+Placing a list of commands between curly braces causes the list to
+be executed in the current shell context. No subshell is created.
+The semicolon (or newline) following @var{list} is required.
+@end table
+
+In addition to the creation of a subshell, there is a subtle difference
+between these two constructs due to historical reasons. The braces
+are @code{reserved words}, so they must be separated from the @var{list}
+by @code{blank}s or other shell metacharacters.
+The parentheses are @code{operators}, and are
+recognized as separate tokens by the shell even if they are not separated
+from the @var{list} by whitespace.
+
+The exit status of both of these constructs is the exit status of
+@var{list}.
+
+@node Coprocesses
+@subsection Coprocesses
+@cindex coprocess
+
+A @code{coprocess} is a shell command preceded by the @code{coproc}
+reserved word.
+A coprocess is executed asynchronously in a subshell, as if the command
+had been terminated with the @samp{&} control operator, with a two-way pipe
+established between the executing shell and the coprocess.
+
+The format for a coprocess is:
+@example
+coproc [@var{NAME}] @var{command} [@var{redirections}]
+@end example
+
+@noindent
+This creates a coprocess named @var{NAME}.
+If @var{NAME} is not supplied, the default name is @var{COPROC}.
+@var{NAME} must not be supplied if @var{command} is a simple
+command (@pxref{Simple Commands}); otherwise, it is interpreted as
+the first word of the simple command.
+
+When the coprocess is executed, the shell creates an array variable
+(@pxref{Arrays})
+named @env{NAME} in the context of the executing shell.
+The standard output of @var{command}
+is connected via a pipe to a file descriptor in the executing shell,
+and that file descriptor is assigned to @env{NAME}[0].
+The standard input of @var{command}
+is connected via a pipe to a file descriptor in the executing shell,
+and that file descriptor is assigned to @env{NAME}[1].
+This pipe is established before any redirections specified by the
+command (@pxref{Redirections}).
+The file descriptors can be utilized as arguments to shell commands
+and redirections using standard word expansions.
+The file descriptors are not available in subshells.
+
+The process ID of the shell spawned to execute the coprocess is
+available as the value of the variable @env{NAME}_PID.
+The @code{wait}
+builtin command may be used to wait for the coprocess to terminate.
+
+Since the coprocess is created as an asynchronous command,
+the @code{coproc} command always returns success.
+The return status of a coprocess is the exit status of @var{command}.
+
+@node GNU Parallel
+@subsection GNU Parallel
+
+There are ways to run commands in parallel that are not built into Bash.
+GNU Parallel is a tool to do just that.
+
+GNU Parallel, as its name suggests, can be used to build and run commands
+in parallel. You may run the same command with different arguments, whether
+they are filenames, usernames, hostnames, or lines read from files. GNU
+Parallel provides shorthand references to many of the most common operations
+(input lines, various portions of the input line, different ways to specify
+the input source, and so on). Parallel can replace @code{xargs} or feed
+commands from its input sources to several different instances of Bash.
+
+For a complete description, refer to the GNU Parallel documentation. A few
+examples should provide a brief introduction to its use.
+
+For example, it is easy to replace @code{xargs} to gzip all html files in the
+current directory and its subdirectories:
+@example
+find . -type f -name '*.html' -print | parallel gzip
+@end example
+@noindent
+If you need to protect special characters such as newlines in file names,
+use find's @option{-print0} option and parallel's @option{-0} option.
+
+You can use Parallel to move files from the current directory when the
+number of files is too large to process with one @code{mv} invocation:
+@example
+ls | parallel mv @{@} destdir
+@end example
+
+As you can see, the @{@} is replaced with each line read from standard input.
+While using @code{ls} will work in most instances, it is not sufficient to
+deal with all filenames.
+If you need to accommodate special characters in filenames, you can use
+
+@example
+find . -depth 1 \! -name '.*' -print0 | parallel -0 mv @{@} destdir
+@end example
+
+@noindent
+as alluded to above.
+
+This will run as many @code{mv} commands as there are files in the current
+directory.
+You can emulate a parallel @code{xargs} by adding the @option{-X} option:
+@example
+find . -depth 1 \! -name '.*' -print0 | parallel -0 -X mv @{@} destdir
+@end example
+
+GNU Parallel can replace certain common idioms that operate on lines read
+from a file (in this case, filenames listed one per line):
+@example
+ while IFS= read -r x; do
+ do-something1 "$x" "config-$x"
+ do-something2 < "$x"
+ done < file | process-output
+@end example
+
+@noindent
+with a more compact syntax reminiscent of lambdas:
+@example
+cat list | parallel "do-something1 @{@} config-@{@} ; do-something2 < @{@}" | process-output
+@end example
+
+Parallel provides a built-in mechanism to remove filename extensions, which
+lends itself to batch file transformations or renaming:
+@example
+ls *.gz | parallel -j+0 "zcat @{@} | bzip2 >@{.@}.bz2 && rm @{@}"
+@end example
+@noindent
+This will recompress all files in the current directory with names ending
+in .gz using bzip2, running one job per CPU (-j+0) in parallel.
+(We use @code{ls} for brevity here; using @code{find} as above is more
+robust in the face of filenames containing unexpected characters.)
+Parallel can take arguments from the command line; the above can also be
+written as
+
+@example
+parallel "zcat @{@} | bzip2 >@{.@}.bz2 && rm @{@}" ::: *.gz
+@end example
+
+If a command generates output, you may want to preserve the input order in
+the output. For instance, the following command
+@example
+@{ echo foss.org.my ; echo debian.org; echo freenetproject.org; @} | parallel traceroute
+@end example
+@noindent
+will display as output the traceroute invocation that finishes first.
+Adding the @option{-k} option
+@example
+@{ echo foss.org.my ; echo debian.org; echo freenetproject.org; @} | parallel -k traceroute
+@end example
+@noindent
+will ensure that the output of @code{traceroute foss.org.my} is displayed first.
+
+Finally, Parallel can be used to run a sequence of shell commands in parallel,
+similar to @samp{cat file | bash}.
+It is not uncommon to take a list of filenames, create a series of shell
+commands to operate on them, and feed that list of commnds to a shell.
+Parallel can speed this up. Assuming that @file{file} contains a list of
+shell commands, one per line,
+
+@example
+parallel -j 10 < file
+@end example
+
+@noindent
+will evaluate the commands using the shell (since no explicit command is
+supplied as an argument), in blocks of ten shell jobs at a time.
+
+@node Shell Functions
+@section Shell Functions
+@cindex shell function
+@cindex functions, shell
+
+Shell functions are a way to group commands for later execution
+using a single name for the group. They are executed just like
+a "regular" command.
+When the name of a shell function is used as a simple command name,
+the list of commands associated with that function name is executed.
+Shell functions are executed in the current
+shell context; no new process is created to interpret them.
+
+Functions are declared using this syntax:
+@rwindex function
+@example
+@var{name} () @var{compound-command} [ @var{redirections} ]
+@end example
+
+or
+
+@example
+function @var{name} [()] @var{compound-command} [ @var{redirections} ]
+@end example
+
+This defines a shell function named @var{name}. The reserved
+word @code{function} is optional.
+If the @code{function} reserved
+word is supplied, the parentheses are optional.
+The @var{body} of the function is the compound command
+@var{compound-command} (@pxref{Compound Commands}).
+That command is usually a @var{list} enclosed between @{ and @}, but
+may be any compound command listed above,
+with one exception: If the @code{function} reserved word is used, but the
+parentheses are not supplied, the braces are required.
+@var{compound-command} is executed whenever @var{name} is specified as the
+name of a command.
+When the shell is in @sc{posix} mode (@pxref{Bash POSIX Mode}),
+@var{name} may not be the same as one of the special builtins
+(@pxref{Special Builtins}).
+Any redirections (@pxref{Redirections}) associated with the shell function
+are performed when the function is executed.
+
+A function definition may be deleted using the @option{-f} option to the
+@code{unset} builtin (@pxref{Bourne Shell Builtins}).
+
+The exit status of a function definition is zero unless a syntax error
+occurs or a readonly function with the same name already exists.
+When executed, the exit status of a function is the exit status of the
+last command executed in the body.
+
+Note that for historical reasons, in the most common usage the curly braces
+that surround the body of the function must be separated from the body by
+@code{blank}s or newlines.
+This is because the braces are reserved words and are only recognized
+as such when they are separated from the command list
+by whitespace or another shell metacharacter.
+Also, when using the braces, the @var{list} must be terminated by a semicolon,
+a @samp{&}, or a newline.
+
+When a function is executed, the arguments to the
+function become the positional parameters
+during its execution (@pxref{Positional Parameters}).
+The special parameter @samp{#} that expands to the number of
+positional parameters is updated to reflect the change.
+Special parameter @code{0} is unchanged.
+The first element of the @env{FUNCNAME} variable is set to the
+name of the function while the function is executing.
+
+All other aspects of the shell execution
+environment are identical between a function and its caller
+with these exceptions:
+the @env{DEBUG} and @env{RETURN} traps
+are not inherited unless the function has been given the
+@code{trace} attribute using the @code{declare} builtin or
+the @code{-o functrace} option has been enabled with
+the @code{set} builtin,
+(in which case all functions inherit the @env{DEBUG} and @env{RETURN} traps),
+and the @env{ERR} trap is not inherited unless the @code{-o errtrace}
+shell option has been enabled.
+@xref{Bourne Shell Builtins}, for the description of the
+@code{trap} builtin.
+
+The @env{FUNCNEST} variable, if set to a numeric value greater
+than 0, defines a maximum function nesting level. Function
+invocations that exceed the limit cause the entire command to
+abort.
+
+If the builtin command @code{return}
+is executed in a function, the function completes and
+execution resumes with the next command after the function
+call.
+Any command associated with the @code{RETURN} trap is executed
+before execution resumes.
+When a function completes, the values of the
+positional parameters and the special parameter @samp{#}
+are restored to the values they had prior to the function's
+execution. If a numeric argument is given to @code{return},
+that is the function's return status; otherwise the function's
+return status is the exit status of the last command executed
+before the @code{return}.
+
+Variables local to the function may be declared with the
+@code{local} builtin. These variables are visible only to
+the function and the commands it invokes.
+
+Function names and definitions may be listed with the
+@option{-f} option to the @code{declare} (@code{typeset})
+builtin command (@pxref{Bash Builtins}).
+The @option{-F} option to @code{declare} or @code{typeset}
+will list the function names only
+(and optionally the source file and line number, if the @code{extdebug}
+shell option is enabled).
+Functions may be exported so that subshells
+automatically have them defined with the
+@option{-f} option to the @code{export} builtin
+(@pxref{Bourne Shell Builtins}).
+Note that shell functions and variables with the same name may result
+in multiple identically-named entries in the environment passed to the
+shell's children.
+Care should be taken in cases where this may cause a problem.
+
+Functions may be recursive.
+The @code{FUNCNEST} variable may be used to limit the depth of the
+function call stack and restrict the number of function invocations.
+By default, no limit is placed on the number of recursive calls.
+
+@node Shell Parameters
+@section Shell Parameters
+@cindex parameters
+@cindex variable, shell
+@cindex shell variable
+
+@menu
+* Positional Parameters:: The shell's command-line arguments.
+* Special Parameters:: Parameters denoted by special characters.
+@end menu
+
+A @var{parameter} is an entity that stores values.
+It can be a @code{name}, a number, or one of the special characters
+listed below.
+A @var{variable} is a parameter denoted by a @code{name}.
+A variable has a @var{value} and zero or more @var{attributes}.
+Attributes are assigned using the @code{declare} builtin command
+(see the description of the @code{declare} builtin in @ref{Bash Builtins}).
+
+A parameter is set if it has been assigned a value. The null string is
+a valid value. Once a variable is set, it may be unset only by using
+the @code{unset} builtin command.
+
+A variable may be assigned to by a statement of the form
+@example
+@var{name}=[@var{value}]
+@end example
+@noindent
+If @var{value}
+is not given, the variable is assigned the null string. All
+@var{value}s undergo tilde expansion, parameter and variable expansion,
+command substitution, arithmetic expansion, and quote
+removal (detailed below). If the variable has its @code{integer}
+attribute set, then @var{value}
+is evaluated as an arithmetic expression even if the @code{$((@dots{}))}
+expansion is not used (@pxref{Arithmetic Expansion}).
+Word splitting is not performed, with the exception
+of @code{"$@@"} as explained below.
+Filename expansion is not performed.
+Assignment statements may also appear as arguments to the
+@code{alias},
+@code{declare}, @code{typeset}, @code{export}, @code{readonly},
+and @code{local} builtin commands (@var{declaration} commands).
+When in @sc{posix} mode (@pxref{Bash POSIX Mode}), these builtins may appear
+in a command after one or more instances of the @code{command} builtin
+and retain these assignment statement properties.
+
+In the context where an assignment statement is assigning a value
+to a shell variable or array index (@pxref{Arrays}), the @samp{+=}
+operator can be used to
+append to or add to the variable's previous value.
+This includes arguments to builtin commands such as @code{declare} that
+accept assignment statements (@var{declaration} commands).
+When @samp{+=} is applied to a variable for which the @var{integer} attribute
+has been set, @var{value} is evaluated as an arithmetic expression and
+added to the variable's current value, which is also evaluated.
+When @samp{+=} is applied to an array variable using compound assignment
+(@pxref{Arrays}), the
+variable's value is not unset (as it is when using @samp{=}), and new
+values are appended to the array beginning at one greater than the array's
+maximum index (for indexed arrays), or added as additional key-value pairs
+in an associative array.
+When applied to a string-valued variable, @var{value} is expanded and
+appended to the variable's value.
+
+A variable can be assigned the @var{nameref} attribute using the
+@option{-n} option to the \fBdeclare\fP or \fBlocal\fP builtin commands
+(@pxref{Bash Builtins})
+to create a @var{nameref}, or a reference to another variable.
+This allows variables to be manipulated indirectly.
+Whenever the nameref variable is referenced, assigned to, unset, or has
+its attributes modified (other than the nameref attribute itself), the
+operation is actually performed on the variable specified by the nameref
+variable's value.
+A nameref is commonly used within shell functions to refer to a variable
+whose name is passed as an argument to the function.
+For instance, if a variable name is passed to a shell function as its first
+argument, running
+@example
+declare -n ref=$1
+@end example
+@noindent
+inside the function creates a nameref variable @var{ref} whose value is
+the variable name passed as the first argument.
+References and assignments to @var{ref}, and changes to its attributes,
+are treated as references, assignments, and attribute modifications
+to the variable whose name was passed as @code{$1}.
+
+If the control variable in a @code{for} loop has the nameref attribute,
+the list of words can be a list of shell variables, and a name reference
+will be established for each word in the list, in turn, when the loop is
+executed.
+Array variables cannot be given the nameref attribute.
+However, nameref variables can reference array variables and subscripted
+array variables.
+Namerefs can be unset using the @option{-n} option to the @code{unset} builtin
+(@pxref{Bourne Shell Builtins}).
+Otherwise, if @code{unset} is executed with the name of a nameref variable
+as an argument, the variable referenced by the nameref variable will be unset.
+
+@node Positional Parameters
+@subsection Positional Parameters
+@cindex parameters, positional
+
+A @var{positional parameter} is a parameter denoted by one or more
+digits, other than the single digit @code{0}. Positional parameters are
+assigned from the shell's arguments when it is invoked,
+and may be reassigned using the @code{set} builtin command.
+Positional parameter @code{N} may be referenced as @code{$@{N@}}, or
+as @code{$N} when @code{N} consists of a single digit.
+Positional parameters may not be assigned to with assignment statements.
+The @code{set} and @code{shift} builtins are used to set and
+unset them (@pxref{Shell Builtin Commands}).
+The positional parameters are
+temporarily replaced when a shell function is executed
+(@pxref{Shell Functions}).
+
+When a positional parameter consisting of more than a single
+digit is expanded, it must be enclosed in braces.
+
+@node Special Parameters
+@subsection Special Parameters
+@cindex parameters, special
+
+The shell treats several parameters specially. These parameters may
+only be referenced; assignment to them is not allowed.
+
+@vtable @code
+
+@item *
+@vindex $*
+($*) Expands to the positional parameters, starting from one.
+When the expansion is not within double quotes, each positional parameter
+expands to a separate word.
+In contexts where it is performed, those words
+are subject to further word splitting and pathname expansion.
+When the expansion occurs within double quotes, it expands to a single word
+with the value of each parameter separated by the first character of the
+@env{IFS} special variable. That is, @code{"$*"} is equivalent
+to @code{"$1@var{c}$2@var{c}@dots{}"}, where @var{c}
+is the first character of the value of the @code{IFS}
+variable.
+If @env{IFS} is unset, the parameters are separated by spaces.
+If @env{IFS} is null, the parameters are joined without intervening
+separators.
+
+@item @@
+@vindex $@@
+($@@) Expands to the positional parameters, starting from one. When the
+expansion occurs within double quotes, each parameter expands to a
+separate word. That is, @code{"$@@"} is equivalent to
+@code{"$1" "$2" @dots{}}.
+If the double-quoted expansion occurs within a word, the expansion of
+the first parameter is joined with the beginning part of the original
+word, and the expansion of the last parameter is joined with the last
+part of the original word.
+When there are no positional parameters, @code{"$@@"} and
+@code{$@@}
+expand to nothing (i.e., they are removed).
+
+@item #
+@vindex $#
+($#) Expands to the number of positional parameters in decimal.
+
+@item ?
+@vindex $?
+($?) Expands to the exit status of the most recently executed foreground
+pipeline.
+
+@item -
+@vindex $-
+($-, a hyphen.) Expands to the current option flags as specified upon
+invocation, by the @code{set}
+builtin command, or those set by the shell itself
+(such as the @option{-i} option).
+
+@item $
+@vindex $$
+($$) Expands to the process @sc{id} of the shell. In a @code{()} subshell, it
+expands to the process @sc{id} of the invoking shell, not the subshell.
+
+@item !
+@vindex $!
+($!) Expands to the process @sc{id} of the job most recently placed into the
+background, whether executed as an asynchronous command or using
+the @code{bg} builtin (@pxref{Job Control Builtins}).
+
+@item 0
+@vindex $0
+($0) Expands to the name of the shell or shell script. This is set at
+shell initialization. If Bash is invoked with a file of commands
+(@pxref{Shell Scripts}), @code{$0} is set to the name of that file.
+If Bash is started with the @option{-c} option (@pxref{Invoking Bash}),
+then @code{$0} is set to the first argument after the string to be
+executed, if one is present. Otherwise, it is set
+to the filename used to invoke Bash, as given by argument zero.
+
+@item _
+@vindex $_
+($_, an underscore.)
+At shell startup, set to the absolute pathname used to invoke the
+shell or shell script being executed as passed in the environment
+or argument list.
+Subsequently, expands to the last argument to the previous command,
+after expansion.
+Also set to the full pathname used to invoke each command executed
+and placed in the environment exported to that command.
+When checking mail, this parameter holds the name of the mail file.
+@end vtable
+
+@node Shell Expansions
+@section Shell Expansions
+@cindex expansion
+
+Expansion is performed on the command line after it has been split into
+@code{token}s. There are seven kinds of expansion performed:
+
+@itemize @bullet
+@item brace expansion
+@item tilde expansion
+@item parameter and variable expansion
+@item command substitution
+@item arithmetic expansion
+@item word splitting
+@item filename expansion
+@end itemize
+
+@menu
+* Brace Expansion:: Expansion of expressions within braces.
+* Tilde Expansion:: Expansion of the ~ character.
+* Shell Parameter Expansion:: How Bash expands variables to their values.
+* Command Substitution:: Using the output of a command as an argument.
+* Arithmetic Expansion:: How to use arithmetic in shell expansions.
+* Process Substitution:: A way to write and read to and from a
+ command.
+* Word Splitting:: How the results of expansion are split into separate
+ arguments.
+* Filename Expansion:: A shorthand for specifying filenames matching patterns.
+* Quote Removal:: How and when quote characters are removed from
+ words.
+@end menu
+
+The order of expansions is:
+brace expansion;
+tilde expansion, parameter and variable expansion, arithmetic expansion,
+and command substitution (done in a left-to-right fashion);
+word splitting;
+and filename expansion.
+
+On systems that can support it, there is an additional expansion
+available: @var{process substitution}.
+This is performed at the
+same time as tilde, parameter, variable, and arithmetic expansion and
+command substitution.
+
+Only brace expansion, word splitting, and filename expansion
+can change the number of words of the expansion; other expansions
+expand a single word to a single word.
+The only exceptions to this are the expansions of
+@code{"$@@"} (@pxref{Special Parameters}) and @code{"$@{@var{name}[@@]@}"}
+(@pxref{Arrays}).
+
+After all expansions, @code{quote removal} (@pxref{Quote Removal})
+is performed.
+
+@node Brace Expansion
+@subsection Brace Expansion
+@cindex brace expansion
+@cindex expansion, brace
+
+Brace expansion is a mechanism by which arbitrary strings may be generated.
+This mechanism is similar to
+@var{filename expansion} (@pxref{Filename Expansion}),
+but the filenames generated need not exist.
+Patterns to be brace expanded take the form of an optional @var{preamble},
+followed by either a series of comma-separated strings or a sequence expression
+between a pair of braces,
+followed by an optional @var{postscript}.
+The preamble is prefixed to each string contained within the braces, and
+the postscript is then appended to each resulting string, expanding left
+to right.
+
+Brace expansions may be nested.
+The results of each expanded string are not sorted; left to right order
+is preserved.
+For example,
+@example
+bash$ echo a@{d,c,b@}e
+ade ace abe
+@end example
+
+A sequence expression takes the form @code{@{@var{x}..@var{y}[..@var{incr}]@}},
+where @var{x} and @var{y} are either integers or single characters,
+and @var{incr}, an optional increment, is an integer.
+When integers are supplied, the expression expands to each number between
+@var{x} and @var{y}, inclusive.
+Supplied integers may be prefixed with @samp{0} to force each term to have the
+same width.
+When either @var{x} or @var{y} begins with a zero, the shell
+attempts to force all generated terms to contain the same number of digits,
+zero-padding where necessary.
+When characters are supplied, the expression expands to each character
+lexicographically between @var{x} and @var{y}, inclusive,
+using the default C locale.
+Note that both @var{x} and @var{y} must be of the same type.
+When the increment is supplied, it is used as the difference between
+each term. The default increment is 1 or -1 as appropriate.
+
+Brace expansion is performed before any other expansions,
+and any characters special to other expansions are preserved
+in the result. It is strictly textual. Bash
+does not apply any syntactic interpretation to the context of the
+expansion or the text between the braces.
+To avoid conflicts with parameter expansion, the string @samp{$@{}
+is not considered eligible for brace expansion.
+
+A correctly-formed brace expansion must contain unquoted opening
+and closing braces, and at least one unquoted comma or a valid
+sequence expression.
+Any incorrectly formed brace expansion is left unchanged.
+
+A @{ or @samp{,} may be quoted with a backslash to prevent its
+being considered part of a brace expression.
+To avoid conflicts with parameter expansion, the string @samp{$@{}
+is not considered eligible for brace expansion.
+
+This construct is typically used as shorthand when the common
+prefix of the strings to be generated is longer than in the
+above example:
+@example
+mkdir /usr/local/src/bash/@{old,new,dist,bugs@}
+@end example
+or
+@example
+chown root /usr/@{ucb/@{ex,edit@},lib/@{ex?.?*,how_ex@}@}
+@end example
+
+@node Tilde Expansion
+@subsection Tilde Expansion
+@cindex tilde expansion
+@cindex expansion, tilde
+
+If a word begins with an unquoted tilde character (@samp{~}), all of the
+characters up to the first unquoted slash (or all characters,
+if there is no unquoted slash) are considered a @var{tilde-prefix}.
+If none of the characters in the tilde-prefix are quoted, the
+characters in the tilde-prefix following the tilde are treated as a
+possible @var{login name}.
+If this login name is the null string, the tilde is replaced with the
+value of the @env{HOME} shell variable.
+If @env{HOME} is unset, the home directory of the user executing the
+shell is substituted instead.
+Otherwise, the tilde-prefix is replaced with the home directory
+associated with the specified login name.
+
+If the tilde-prefix is @samp{~+}, the value of
+the shell variable @env{PWD} replaces the tilde-prefix.
+If the tilde-prefix is @samp{~-}, the value of the shell variable
+@env{OLDPWD}, if it is set, is substituted.
+
+If the characters following the tilde in the tilde-prefix consist of a
+number @var{N}, optionally prefixed by a @samp{+} or a @samp{-},
+the tilde-prefix is replaced with the
+corresponding element from the directory stack, as it would be displayed
+by the @code{dirs} builtin invoked with the characters following tilde
+in the tilde-prefix as an argument (@pxref{The Directory Stack}).
+If the tilde-prefix, sans the tilde, consists of a number without a
+leading @samp{+} or @samp{-}, @samp{+} is assumed.
+
+If the login name is invalid, or the tilde expansion fails, the word is
+left unchanged.
+
+Each variable assignment is checked for unquoted tilde-prefixes immediately
+following a @samp{:} or the first @samp{=}.
+In these cases, tilde expansion is also performed.
+Consequently, one may use filenames with tildes in assignments to
+@env{PATH}, @env{MAILPATH}, and @env{CDPATH},
+and the shell assigns the expanded value.
+
+The following table shows how Bash treats unquoted tilde-prefixes:
+
+@table @code
+@item ~
+The value of @code{$HOME}
+@item ~/foo
+@file{$HOME/foo}
+
+@item ~fred/foo
+The subdirectory @code{foo} of the home directory of the user
+@code{fred}
+
+@item ~+/foo
+@file{$PWD/foo}
+
+@item ~-/foo
+@file{$@{OLDPWD-'~-'@}/foo}
+
+@item ~@var{N}
+The string that would be displayed by @samp{dirs +@var{N}}
+
+@item ~+@var{N}
+The string that would be displayed by @samp{dirs +@var{N}}
+
+@item ~-@var{N}
+The string that would be displayed by @samp{dirs -@var{N}}
+@end table
+
+@node Shell Parameter Expansion
+@subsection Shell Parameter Expansion
+@cindex parameter expansion
+@cindex expansion, parameter
+
+The @samp{$} character introduces parameter expansion,
+command substitution, or arithmetic expansion. The parameter name
+or symbol to be expanded may be enclosed in braces, which
+are optional but serve to protect the variable to be expanded from
+characters immediately following it which could be
+interpreted as part of the name.
+
+When braces are used, the matching ending brace is the first @samp{@}}
+not escaped by a backslash or within a quoted string, and not within an
+embedded arithmetic expansion, command substitution, or parameter
+expansion.
+
+The basic form of parameter expansion is $@{@var{parameter}@}.
+The value of @var{parameter} is substituted.
+The @var{parameter} is a shell parameter as described above
+(@pxref{Shell Parameters}) or an array reference (@pxref{Arrays}).
+The braces are required when @var{parameter}
+is a positional parameter with more than one digit,
+or when @var{parameter} is followed by a character that is not to be
+interpreted as part of its name.
+
+If the first character of @var{parameter} is an exclamation point (!),
+it introduces a level of variable indirection.
+Bash uses the value of the variable formed from the rest of
+@var{parameter} as the name of the variable; this variable is then
+expanded and that value is used in the rest of the substitution, rather
+than the value of @var{parameter} itself.
+This is known as @code{indirect expansion}.
+The exceptions to this are the expansions of $@{!@var{prefix}*@}
+and $@{!@var{name}[@@]@}
+described below.
+The exclamation point must immediately follow the left brace in order to
+introduce indirection.
+
+In each of the cases below, @var{word} is subject to tilde expansion,
+parameter expansion, command substitution, and arithmetic expansion.
+
+When not performing substring expansion, using the form described
+below (e.g., @samp{:-}), Bash tests for a parameter that is unset or null.
+Omitting the colon results in a test only for a parameter that is unset.
+Put another way, if the colon is included,
+the operator tests for both @var{parameter}'s existence and that its value
+is not null; if the colon is omitted, the operator tests only for existence.
+
+@table @code
+
+@item $@{@var{parameter}:@minus{}@var{word}@}
+If @var{parameter} is unset or null, the expansion of
+@var{word} is substituted. Otherwise, the value of
+@var{parameter} is substituted.
+
+@item $@{@var{parameter}:=@var{word}@}
+If @var{parameter}
+is unset or null, the expansion of @var{word}
+is assigned to @var{parameter}.
+The value of @var{parameter} is then substituted.
+Positional parameters and special parameters may not be assigned to
+in this way.
+
+@item $@{@var{parameter}:?@var{word}@}
+If @var{parameter}
+is null or unset, the expansion of @var{word} (or a message
+to that effect if @var{word}
+is not present) is written to the standard error and the shell, if it
+is not interactive, exits. Otherwise, the value of @var{parameter} is
+substituted.
+
+@item $@{@var{parameter}:+@var{word}@}
+If @var{parameter}
+is null or unset, nothing is substituted, otherwise the expansion of
+@var{word} is substituted.
+
+@item $@{@var{parameter}:@var{offset}@}
+@itemx $@{@var{parameter}:@var{offset}:@var{length}@}
+This is referred to as Substring Expansion.
+It expands to up to @var{length} characters of the value of @var{parameter}
+starting at the character specified by @var{offset}.
+If @var{parameter} is @samp{@@}, an indexed array subscripted by
+@samp{@@} or @samp{*}, or an associative array name, the results differ as
+described below.
+If @var{length} is omitted, it expands to the substring of the value of
+@var{parameter} starting at the character specified by @var{offset}
+and extending to the end of the value.
+@var{length} and @var{offset} are arithmetic expressions
+(@pxref{Shell Arithmetic}).
+
+If @var{offset} evaluates to a number less than zero, the value
+is used as an offset in characters
+from the end of the value of @var{parameter}.
+If @var{length} evaluates to a number less than zero,
+it is interpreted as an offset in characters
+from the end of the value of @var{parameter} rather than
+a number of characters, and the expansion is the characters between
+@var{offset} and that result.
+Note that a negative offset must be separated from the colon by at least
+one space to avoid being confused with the @samp{:-} expansion.
+
+Here are some examples illustrating substring expansion on parameters and
+subscripted arrays:
+
+@verbatim
+$ string=01234567890abcdefgh
+$ echo ${string:7}
+7890abcdefgh
+$ echo ${string:7:0}
+
+$ echo ${string:7:2}
+78
+$ echo ${string:7:-2}
+7890abcdef
+$ echo ${string: -7}
+bcdefgh
+$ echo ${string: -7:0}
+
+$ echo ${string: -7:2}
+bc
+$ echo ${string: -7:-2}
+bcdef
+$ set -- 01234567890abcdefgh
+$ echo ${1:7}
+7890abcdefgh
+$ echo ${1:7:0}
+
+$ echo ${1:7:2}
+78
+$ echo ${1:7:-2}
+7890abcdef
+$ echo ${1: -7}
+bcdefgh
+$ echo ${1: -7:0}
+
+$ echo ${1: -7:2}
+bc
+$ echo ${1: -7:-2}
+bcdef
+$ array[0]=01234567890abcdefgh
+$ echo ${array[0]:7}
+7890abcdefgh
+$ echo ${array[0]:7:0}
+
+$ echo ${array[0]:7:2}
+78
+$ echo ${array[0]:7:-2}
+7890abcdef
+$ echo ${array[0]: -7}
+bcdefgh
+$ echo ${array[0]: -7:0}
+
+$ echo ${array[0]: -7:2}
+bc
+$ echo ${array[0]: -7:-2}
+bcdef
+@end verbatim
+
+If @var{parameter} is @samp{@@}, the result is @var{length} positional
+parameters beginning at @var{offset}.
+A negative @var{offset} is taken relative to one greater than the greatest
+positional parameter, so an offset of -1 evaluates to the last positional
+parameter.
+It is an expansion error if @var{length} evaluates to a number less than zero.
+
+The following examples illustrate substring expansion using positional
+parameters:
+
+@verbatim
+$ set -- 1 2 3 4 5 6 7 8 9 0 a b c d e f g h
+$ echo ${@:7}
+7 8 9 0 a b c d e f g h
+$ echo ${@:7:0}
+
+$ echo ${@:7:2}
+7 8
+$ echo ${@:7:-2}
+bash: -2: substring expression < 0
+$ echo ${@: -7:2}
+b c
+$ echo ${@:0}
+./bash 1 2 3 4 5 6 7 8 9 0 a b c d e f g h
+$ echo ${@:0:2}
+./bash 1
+$ echo ${@: -7:0}
+
+@end verbatim
+
+If @var{parameter} is an indexed array name subscripted
+by @samp{@@} or @samp{*}, the result is the @var{length}
+members of the array beginning with @code{$@{@var{parameter}[@var{offset}]@}}.
+A negative @var{offset} is taken relative to one greater than the maximum
+index of the specified array.
+It is an expansion error if @var{length} evaluates to a number less than zero.
+
+These examples show how you can use substring expansion with indexed
+arrays:
+
+@verbatim
+$ array=(0 1 2 3 4 5 6 7 8 9 0 a b c d e f g h)
+$ echo ${array[@]:7}
+7 8 9 0 a b c d e f g h
+$ echo ${array[@]:7:2}
+7 8
+$ echo ${array[@]: -7:2}
+b c
+$ echo ${array[@]: -7:-2}
+bash: -2: substring expression < 0
+$ echo ${array[@]:0}
+0 1 2 3 4 5 6 7 8 9 0 a b c d e f g h
+$ echo ${array[@]:0:2}
+0 1
+$ echo ${array[@]: -7:0}
+
+@end verbatim
+
+Substring expansion applied to an associative array produces undefined
+results.
+
+Substring indexing is zero-based unless the positional parameters
+are used, in which case the indexing starts at 1 by default.
+If @var{offset} is 0, and the positional parameters are used, @code{$@@} is
+prefixed to the list.
+
+@item $@{!@var{prefix}*@}
+@itemx $@{!@var{prefix}@@@}
+Expands to the names of variables whose names begin with @var{prefix},
+separated by the first character of the @env{IFS} special variable.
+When @samp{@@} is used and the expansion appears within double quotes, each
+variable name expands to a separate word.
+
+@item $@{!@var{name}[@@]@}
+@itemx $@{!@var{name}[*]@}
+If @var{name} is an array variable, expands to the list of array indices
+(keys) assigned in @var{name}.
+If @var{name} is not an array, expands to 0 if @var{name} is set and null
+otherwise.
+When @samp{@@} is used and the expansion appears within double quotes, each
+key expands to a separate word.
+
+@item $@{#@var{parameter}@}
+The length in characters of the expanded value of @var{parameter} is
+substituted.
+If @var{parameter} is @samp{*} or @samp{@@}, the value substituted
+is the number of positional parameters.
+If @var{parameter} is an array name subscripted by @samp{*} or @samp{@@},
+the value substituted is the number of elements in the array.
+If @var{parameter}
+is an indexed array name subscripted by a negative number, that number is
+interpreted as relative to one greater than the maximum index of
+@var{parameter}, so negative indices count back from the end of the
+array, and an index of -1 references the last element.
+
+@item $@{@var{parameter}#@var{word}@}
+@itemx $@{@var{parameter}##@var{word}@}
+The @var{word}
+is expanded to produce a pattern just as in filename
+expansion (@pxref{Filename Expansion}). If the pattern matches
+the beginning of the expanded value of @var{parameter},
+then the result of the expansion is the expanded value of @var{parameter}
+with the shortest matching pattern (the @samp{#} case) or the
+longest matching pattern (the @samp{##} case) deleted.
+If @var{parameter} is @samp{@@} or @samp{*},
+the pattern removal operation is applied to each positional
+parameter in turn, and the expansion is the resultant list.
+If @var{parameter} is an array variable subscripted with
+@samp{@@} or @samp{*},
+the pattern removal operation is applied to each member of the
+array in turn, and the expansion is the resultant list.
+
+@item $@{@var{parameter}%@var{word}@}
+@itemx $@{@var{parameter}%%@var{word}@}
+The @var{word} is expanded to produce a pattern just as in
+filename expansion.
+If the pattern matches a trailing portion of the expanded value of
+@var{parameter}, then the result of the expansion is the value of
+@var{parameter} with the shortest matching pattern (the @samp{%} case)
+or the longest matching pattern (the @samp{%%} case) deleted.
+If @var{parameter} is @samp{@@} or @samp{*},
+the pattern removal operation is applied to each positional
+parameter in turn, and the expansion is the resultant list.
+If @var{parameter}
+is an array variable subscripted with @samp{@@} or @samp{*},
+the pattern removal operation is applied to each member of the
+array in turn, and the expansion is the resultant list.
+
+@item $@{@var{parameter}/@var{pattern}/@var{string}@}
+
+The @var{pattern} is expanded to produce a pattern just as in
+filename expansion.
+@var{Parameter} is expanded and the longest match of @var{pattern}
+against its value is replaced with @var{string}.
+If @var{pattern} begins with @samp{/}, all matches of @var{pattern} are
+replaced with @var{string}. Normally only the first match is replaced.
+If @var{pattern} begins with @samp{#}, it must match at the beginning
+of the expanded value of @var{parameter}.
+If @var{pattern} begins with @samp{%}, it must match at the end
+of the expanded value of @var{parameter}.
+If @var{string} is null, matches of @var{pattern} are deleted
+and the @code{/} following @var{pattern} may be omitted.
+If the @code{nocasematch} shell option
+(see the description of @code{shopt} in @ref{The Shopt Builtin})
+is enabled, the match is performed without regard to the case
+of alphabetic characters.
+If @var{parameter} is @samp{@@} or @samp{*},
+the substitution operation is applied to each positional
+parameter in turn, and the expansion is the resultant list.
+If @var{parameter}
+is an array variable subscripted with @samp{@@} or @samp{*},
+the substitution operation is applied to each member of the
+array in turn, and the expansion is the resultant list.
+
+@item $@{@var{parameter}^@var{pattern}@}
+@itemx $@{@var{parameter}^^@var{pattern}@}
+@itemx $@{@var{parameter},@var{pattern}@}
+@itemx $@{@var{parameter},,@var{pattern}@}
+This expansion modifies the case of alphabetic characters in @var{parameter}.
+The @var{pattern} is expanded to produce a pattern just as in
+filename expansion.
+Each character in the expanded value of @var{parameter} is tested against
+@var{pattern}, and, if it matches the pattern, its case is converted.
+The pattern should not attempt to match more than one character.
+The @samp{^} operator converts lowercase letters matching @var{pattern}
+to uppercase; the @samp{,} operator converts matching uppercase letters
+to lowercase.
+The @samp{^^} and @samp{,,} expansions convert each matched character in the
+expanded value; the @samp{^} and @samp{,} expansions match and convert only
+the first character in the expanded value.
+If @var{pattern} is omitted, it is treated like a @samp{?}, which matches
+every character.
+If @var{parameter} is @samp{@@} or @samp{*},
+the case modification operation is applied to each positional
+parameter in turn, and the expansion is the resultant list.
+If @var{parameter}
+is an array variable subscripted with @samp{@@} or @samp{*},
+the case modification operation is applied to each member of the
+array in turn, and the expansion is the resultant list.
+
+@item $@{@var{parameter}@@@var{operator}@}
+The expansion is either a transformation of the value of @var{parameter}
+or information about @var{parameter} itself, depending on the value of
+@var{operator}. Each @var{operator} is a single letter:
+
+@table @code
+@item Q
+The expansion is a string that is the value of @var{parameter} quoted in a
+format that can be reused as input.
+@item E
+The expansion is a string that is the value of @var{parameter} with backslash
+escape sequences expanded as with the @code{$'@dots{}'} quoting mechansim.
+@item P
+The expansion is a string that is the result of expanding the value of
+@var{parameter} as if it were a prompt string (@pxref{Controlling the Prompt}).
+@item A
+The expansion is a string in the form of a @code{declare} command that, if
+evaluated, will recreate @var{parameter} with its attributes and value.
+@item a
+The expansion is a string consisting of flag values representing
+@var{parameter}'s attributes.
+@end table
+
+If @var{parameter} is @samp{@@} or @samp{*},
+the operation is applied to each positional
+parameter in turn, and the expansion is the resultant list.
+If @var{parameter}
+is an array variable subscripted with @samp{@@} or @samp{*},
+the operation is applied to each member of the
+array in turn, and the expansion is the resultant list.
+
+The result of the expansion is subject to word splitting and pathname
+expansion as described below.
+@end table
+
+@node Command Substitution
+@subsection Command Substitution
+@cindex command substitution
+
+Command substitution allows the output of a command to replace
+the command itself.
+Command substitution occurs when a command is enclosed as follows:
+@example
+$(@var{command})
+@end example
+@noindent
+or
+@example
+`@var{command}`
+@end example
+
+@noindent
+Bash performs the expansion by executing @var{command} and
+replacing the command substitution with the standard output of the
+command, with any trailing newlines deleted.
+Embedded newlines are not deleted, but they may be removed during
+word splitting.
+The command substitution @code{$(cat @var{file})} can be
+replaced by the equivalent but faster @code{$(< @var{file})}.
+
+When the old-style backquote form of substitution is used,
+backslash retains its literal meaning except when followed by
+@samp{$}, @samp{`}, or @samp{\}.
+The first backquote not preceded by a backslash terminates the
+command substitution.
+When using the @code{$(@var{command})} form, all characters between
+the parentheses make up the command; none are treated specially.
+
+Command substitutions may be nested. To nest when using the backquoted
+form, escape the inner backquotes with backslashes.
+
+If the substitution appears within double quotes, word splitting and
+filename expansion are not performed on the results.
+
+@node Arithmetic Expansion
+@subsection Arithmetic Expansion
+@cindex expansion, arithmetic
+@cindex arithmetic expansion
+
+Arithmetic expansion allows the evaluation of an arithmetic expression
+and the substitution of the result. The format for arithmetic expansion is:
+
+@example
+$(( @var{expression} ))
+@end example
+
+The expression is treated as if it were within double quotes, but
+a double quote inside the parentheses is not treated specially.
+All tokens in the expression undergo parameter and variable expansion,
+command substitution, and quote removal.
+The result is treated as the arithmetic expression to be evaluated.
+Arithmetic expansions may be nested.
+
+The evaluation is performed according to the rules listed below
+(@pxref{Shell Arithmetic}).
+If the expression is invalid, Bash prints a message indicating
+failure to the standard error and no substitution occurs.
+
+@node Process Substitution
+@subsection Process Substitution
+@cindex process substitution
+
+Process substitution is supported on systems that support named
+pipes (@sc{fifo}s) or the @file{/dev/fd} method of naming open files.
+It takes the form of
+@example
+<(@var{list})
+@end example
+@noindent
+or
+@example
+>(@var{list})
+@end example
+@noindent
+The process @var{list} is run with its input or output connected to a
+@sc{fifo} or some file in @file{/dev/fd}. The name of this file is
+passed as an argument to the current command as the result of the
+expansion. If the @code{>(@var{list})} form is used, writing to
+the file will provide input for @var{list}. If the
+@code{<(@var{list})} form is used, the file passed as an
+argument should be read to obtain the output of @var{list}.
+Note that no space may appear between the @code{<} or @code{>}
+and the left parenthesis, otherwise the construct would be interpreted
+as a redirection.
+
+When available, process substitution is performed simultaneously with
+parameter and variable expansion, command substitution, and arithmetic
+expansion.
+
+@node Word Splitting
+@subsection Word Splitting
+@cindex word splitting
+
+The shell scans the results of parameter expansion, command substitution,
+and arithmetic expansion that did not occur within double quotes for
+word splitting.
+
+The shell treats each character of @env{$IFS} as a delimiter, and splits
+the results of the other expansions into words using these characters
+as field terminators.
+If @env{IFS} is unset, or its value is exactly @code{<space><tab><newline>},
+the default, then sequences of
+@code{ <space>}, @code{<tab>}, and @code{<newline>}
+at the beginning and end of the results of the previous
+expansions are ignored, and any sequence of @env{IFS}
+characters not at the beginning or end serves to delimit words.
+If @env{IFS} has a value other than the default, then sequences of
+the whitespace characters @code{space} and @code{tab}
+are ignored at the beginning and end of the
+word, as long as the whitespace character is in the
+value of @env{IFS} (an @env{IFS} whitespace character).
+Any character in @env{IFS} that is not @env{IFS}
+whitespace, along with any adjacent @env{IFS}
+whitespace characters, delimits a field. A sequence of @env{IFS}
+whitespace characters is also treated as a delimiter.
+If the value of @env{IFS} is null, no word splitting occurs.
+
+Explicit null arguments (@code{""} or @code{''}) are retained.
+Unquoted implicit null arguments, resulting from the expansion of
+parameters that have no values, are removed.
+If a parameter with no value is expanded within double quotes, a
+null argument results and is retained.
+
+Note that if no expansion occurs, no splitting
+is performed.
+
+@node Filename Expansion
+@subsection Filename Expansion
+@menu
+* Pattern Matching:: How the shell matches patterns.
+@end menu
+@cindex expansion, filename
+@cindex expansion, pathname
+@cindex filename expansion
+@cindex pathname expansion
+
+After word splitting, unless the @option{-f} option has been set
+(@pxref{The Set Builtin}), Bash scans each word for the characters
+@samp{*}, @samp{?}, and @samp{[}.
+If one of these characters appears, then the word is
+regarded as a @var{pattern},
+and replaced with an alphabetically sorted list of
+filenames matching the pattern (@pxref{Pattern Matching}).
+If no matching filenames are found,
+and the shell option @code{nullglob} is disabled, the word is left
+unchanged.
+If the @code{nullglob} option is set, and no matches are found, the word
+is removed.
+If the @code{failglob} shell option is set, and no matches are found,
+an error message is printed and the command is not executed.
+If the shell option @code{nocaseglob} is enabled, the match is performed
+without regard to the case of alphabetic characters.
+
+When a pattern is used for filename expansion, the character @samp{.}
+at the start of a filename or immediately following a slash
+must be matched explicitly, unless the shell option @code{dotglob} is set.
+When matching a filename, the slash character must always be
+matched explicitly.
+In other cases, the @samp{.} character is not treated specially.
+
+See the description of @code{shopt} in @ref{The Shopt Builtin},
+for a description of the @code{nocaseglob}, @code{nullglob},
+@code{failglob}, and @code{dotglob} options.
+
+The @env{GLOBIGNORE}
+shell variable may be used to restrict the set of filenames matching a
+pattern. If @env{GLOBIGNORE}
+is set, each matching filename that also matches one of the patterns in
+@env{GLOBIGNORE} is removed from the list of matches.
+If the @code{nocaseglob} option is set, the matching against the patterns in
+@env{GLOBIGNORE} is performed without regard to case.
+The filenames
+@file{.} and @file{..}
+are always ignored when @env{GLOBIGNORE}
+is set and not null.
+However, setting @env{GLOBIGNORE} to a non-null value has the effect of
+enabling the @code{dotglob}
+shell option, so all other filenames beginning with a
+@samp{.} will match.
+To get the old behavior of ignoring filenames beginning with a
+@samp{.}, make @samp{.*} one of the patterns in @env{GLOBIGNORE}.
+The @code{dotglob} option is disabled when @env{GLOBIGNORE}
+is unset.
+
+@node Pattern Matching
+@subsubsection Pattern Matching
+@cindex pattern matching
+@cindex matching, pattern
+
+Any character that appears in a pattern, other than the special pattern
+characters described below, matches itself.
+The @sc{nul} character may not occur in a pattern.
+A backslash escapes the following character; the
+escaping backslash is discarded when matching.
+The special pattern characters must be quoted if they are to be matched
+literally.
+
+The special pattern characters have the following meanings:
+@table @code
+@item *
+Matches any string, including the null string.
+When the @code{globstar} shell option is enabled, and @samp{*} is used in
+a filename expansion context, two adjacent @samp{*}s used as a single
+pattern will match all files and zero or more directories and
+subdirectories.
+If followed by a @samp{/}, two adjacent @samp{*}s will match only
+directories and subdirectories.
+@item ?
+Matches any single character.
+@item [@dots{}]
+Matches any one of the enclosed characters. A pair of characters
+separated by a hyphen denotes a @var{range expression};
+any character that falls between those two characters, inclusive,
+using the current locale's collating sequence and character set,
+is matched. If the first character following the
+@samp{[} is a @samp{!} or a @samp{^}
+then any character not enclosed is matched. A @samp{@minus{}}
+may be matched by including it as the first or last character
+in the set. A @samp{]} may be matched by including it as the first
+character in the set.
+The sorting order of characters in range expressions is determined by
+the current locale and the values of the
+@env{LC_COLLATE} and @env{LC_ALL} shell variables, if set.
+
+For example, in the default C locale, @samp{[a-dx-z]} is equivalent to
+@samp{[abcdxyz]}. Many locales sort characters in dictionary order, and in
+these locales @samp{[a-dx-z]} is typically not equivalent to @samp{[abcdxyz]};
+it might be equivalent to @samp{[aBbCcDdxXyYz]}, for example. To obtain
+the traditional interpretation of ranges in bracket expressions, you can
+force the use of the C locale by setting the @env{LC_COLLATE} or
+@env{LC_ALL} environment variable to the value @samp{C}, or enable the
+@code{globasciiranges} shell option.
+
+Within @samp{[} and @samp{]}, @var{character classes} can be specified
+using the syntax
+@code{[:}@var{class}@code{:]}, where @var{class} is one of the
+following classes defined in the @sc{posix} standard:
+@example
+alnum alpha ascii blank cntrl digit graph lower
+print punct space upper word xdigit
+@end example
+@noindent
+A character class matches any character belonging to that class.
+The @code{word} character class matches letters, digits, and the character
+@samp{_}.
+
+Within @samp{[} and @samp{]}, an @var{equivalence class} can be
+specified using the syntax @code{[=}@var{c}@code{=]}, which
+matches all characters with the same collation weight (as defined
+by the current locale) as the character @var{c}.
+
+Within @samp{[} and @samp{]}, the syntax @code{[.}@var{symbol}@code{.]}
+matches the collating symbol @var{symbol}.
+@end table
+
+If the @code{extglob} shell option is enabled using the @code{shopt}
+builtin, several extended pattern matching operators are recognized.
+In the following description, a @var{pattern-list} is a list of one
+or more patterns separated by a @samp{|}.
+Composite patterns may be formed using one or more of the following
+sub-patterns:
+
+@table @code
+@item ?(@var{pattern-list})
+Matches zero or one occurrence of the given patterns.
+
+@item *(@var{pattern-list})
+Matches zero or more occurrences of the given patterns.
+
+@item +(@var{pattern-list})
+Matches one or more occurrences of the given patterns.
+
+@item @@(@var{pattern-list})
+Matches one of the given patterns.
+
+@item !(@var{pattern-list})
+Matches anything except one of the given patterns.
+@end table
+
+@node Quote Removal
+@subsection Quote Removal
+
+After the preceding expansions, all unquoted occurrences of the
+characters @samp{\}, @samp{'}, and @samp{"} that did not
+result from one of the above expansions are removed.
+
+@node Redirections
+@section Redirections
+@cindex redirection
+
+Before a command is executed, its input and output
+may be @var{redirected}
+using a special notation interpreted by the shell.
+Redirection allows commands' file handles to be
+duplicated, opened, closed,
+made to refer to different files,
+and can change the files the command reads from and writes to.
+Redirection may also be used to modify file handles in the
+current shell execution environment. The following redirection
+operators may precede or appear anywhere within a
+simple command or may follow a command.
+Redirections are processed in the order they appear, from
+left to right.
+
+Each redirection that may be preceded by a file descriptor number
+may instead be preceded by a word of the form @{@var{varname}@}.
+In this case, for each redirection operator except
+>&- and <&-, the shell will allocate a file descriptor greater
+than 10 and assign it to @{@var{varname}@}. If >&- or <&- is preceded
+by @{@var{varname}@}, the value of @var{varname} defines the file
+descriptor to close.
+
+In the following descriptions, if the file descriptor number is
+omitted, and the first character of the redirection operator is
+@samp{<}, the redirection refers to the standard input (file
+descriptor 0). If the first character of the redirection operator
+is @samp{>}, the redirection refers to the standard output (file
+descriptor 1).
+
+The word following the redirection operator in the following
+descriptions, unless otherwise noted, is subjected to brace expansion,
+tilde expansion, parameter expansion, command substitution, arithmetic
+expansion, quote removal, filename expansion, and word splitting.
+If it expands to more than one word, Bash reports an error.
+
+Note that the order of redirections is significant. For example,
+the command
+@example
+ls > @var{dirlist} 2>&1
+@end example
+@noindent
+directs both standard output (file descriptor 1) and standard error
+(file descriptor 2) to the file @var{dirlist}, while the command
+@example
+ls 2>&1 > @var{dirlist}
+@end example
+@noindent
+directs only the standard output to file @var{dirlist},
+because the standard error was made a copy of the standard output
+before the standard output was redirected to @var{dirlist}.
+
+Bash handles several filenames specially when they are used in
+redirections, as described in the following table:
+
+@table @code
+@item /dev/fd/@var{fd}
+If @var{fd} is a valid integer, file descriptor @var{fd} is duplicated.
+
+@item /dev/stdin
+File descriptor 0 is duplicated.
+
+@item /dev/stdout
+File descriptor 1 is duplicated.
+
+@item /dev/stderr
+File descriptor 2 is duplicated.
+
+@item /dev/tcp/@var{host}/@var{port}
+If @var{host} is a valid hostname or Internet address, and @var{port}
+is an integer port number or service name, Bash attempts to open
+the corresponding TCP socket.
+
+@item /dev/udp/@var{host}/@var{port}
+If @var{host} is a valid hostname or Internet address, and @var{port}
+is an integer port number or service name, Bash attempts to open
+the corresponding UDP socket.
+@end table
+
+A failure to open or create a file causes the redirection to fail.
+
+Redirections using file descriptors greater than 9 should be used with
+care, as they may conflict with file descriptors the shell uses
+internally.
+
+@subsection Redirecting Input
+Redirection of input causes the file whose name results from
+the expansion of @var{word}
+to be opened for reading on file descriptor @code{n},
+or the standard input (file descriptor 0) if @code{n}
+is not specified.
+
+The general format for redirecting input is:
+@example
+[@var{n}]<@var{word}
+@end example
+
+@subsection Redirecting Output
+Redirection of output causes the file whose name results from
+the expansion of @var{word}
+to be opened for writing on file descriptor @var{n},
+or the standard output (file descriptor 1) if @var{n}
+is not specified. If the file does not exist it is created;
+if it does exist it is truncated to zero size.
+
+The general format for redirecting output is:
+@example
+[@var{n}]>[|]@var{word}
+@end example
+
+If the redirection operator is @samp{>}, and the @code{noclobber}
+option to the @code{set} builtin has been enabled, the redirection
+will fail if the file whose name results from the expansion of
+@var{word} exists and is a regular file.
+If the redirection operator is @samp{>|}, or the redirection operator is
+@samp{>} and the @code{noclobber} option is not enabled, the redirection
+is attempted even if the file named by @var{word} exists.
+
+@subsection Appending Redirected Output
+Redirection of output in this fashion
+causes the file whose name results from
+the expansion of @var{word}
+to be opened for appending on file descriptor @var{n},
+or the standard output (file descriptor 1) if @var{n}
+is not specified. If the file does not exist it is created.
+
+The general format for appending output is:
+@example
+[@var{n}]>>@var{word}
+@end example
+
+@subsection Redirecting Standard Output and Standard Error
+This construct allows both the
+standard output (file descriptor 1) and
+the standard error output (file descriptor 2)
+to be redirected to the file whose name is the
+expansion of @var{word}.
+
+There are two formats for redirecting standard output and
+standard error:
+@example
+&>@var{word}
+@end example
+@noindent
+and
+@example
+>&@var{word}
+@end example
+@noindent
+Of the two forms, the first is preferred.
+This is semantically equivalent to
+@example
+>@var{word} 2>&1
+@end example
+When using the second form, @var{word} may not expand to a number or
+@samp{-}. If it does, other redirection operators apply
+(see Duplicating File Descriptors below) for compatibility reasons.
+
+@subsection Appending Standard Output and Standard Error
+This construct allows both the
+standard output (file descriptor 1) and
+the standard error output (file descriptor 2)
+to be appended to the file whose name is the
+expansion of @var{word}.
+
+The format for appending standard output and standard error is:
+@example
+&>>@var{word}
+@end example
+@noindent
+This is semantically equivalent to
+@example
+>>@var{word} 2>&1
+@end example
+(see Duplicating File Descriptors below).
+
+@subsection Here Documents
+This type of redirection instructs the shell to read input from the
+current source until a line containing only @var{word}
+(with no trailing blanks) is seen. All of
+the lines read up to that point are then used as the standard
+input (or file descriptor @var{n} if @var{n} is specified) for a command.
+
+The format of here-documents is:
+@example
+[@var{n}]<<[@minus{}]@var{word}
+ @var{here-document}
+@var{delimiter}
+@end example
+
+No parameter and variable expansion, command substitution,
+arithmetic expansion, or filename expansion is performed on
+@var{word}. If any characters in @var{word} are quoted, the
+@var{delimiter} is the result of quote removal on @var{word},
+and the lines in the here-document are not expanded.
+If @var{word} is unquoted,
+all lines of the here-document are subjected to
+parameter expansion, command substitution, and arithmetic expansion,
+the character sequence @code{\newline} is ignored, and @samp{\}
+must be used to quote the characters
+@samp{\}, @samp{$}, and @samp{`}.
+
+If the redirection operator is @samp{<<-},
+then all leading tab characters are stripped from input lines and the
+line containing @var{delimiter}.
+This allows here-documents within shell scripts to be indented in a
+natural fashion.
+
+@subsection Here Strings
+A variant of here documents, the format is:
+@example
+[@var{n}]<<< @var{word}
+@end example
+
+The @var{word} undergoes
+brace expansion, tilde expansion, parameter and variable expansion,
+command substitution, arithmetic expansion, and quote removal.
+Pathname expansion and word splitting are not performed.
+The result is supplied as a single string to the command on its
+standard input (or file descriptor @var{n} if @var{n} is specified).
+
+@subsection Duplicating File Descriptors
+The redirection operator
+@example
+[@var{n}]<&@var{word}
+@end example
+@noindent
+is used to duplicate input file descriptors.
+If @var{word}
+expands to one or more digits, the file descriptor denoted by @var{n}
+is made to be a copy of that file descriptor.
+If the digits in @var{word} do not specify a file descriptor open for
+input, a redirection error occurs.
+If @var{word}
+evaluates to @samp{-}, file descriptor @var{n} is closed.
+If @var{n} is not specified, the standard input (file descriptor 0) is used.
+
+The operator
+@example
+[@var{n}]>&@var{word}
+@end example
+@noindent
+is used similarly to duplicate output file descriptors. If
+@var{n} is not specified, the standard output (file descriptor 1) is used.
+If the digits in @var{word} do not specify a file descriptor open for
+output, a redirection error occurs.
+If @var{word}
+evaluates to @samp{-}, file descriptor @var{n} is closed.
+As a special case, if @var{n} is omitted, and @var{word} does not
+expand to one or more digits or @samp{-}, the standard output and standard
+error are redirected as described previously.
+
+@subsection Moving File Descriptors
+The redirection operator
+@example
+[@var{n}]<&@var{digit}-
+@end example
+@noindent
+moves the file descriptor @var{digit} to file descriptor @var{n},
+or the standard input (file descriptor 0) if @var{n} is not specified.
+@var{digit} is closed after being duplicated to @var{n}.
+
+Similarly, the redirection operator
+@example
+[@var{n}]>&@var{digit}-
+@end example
+@noindent
+moves the file descriptor @var{digit} to file descriptor @var{n},
+or the standard output (file descriptor 1) if @var{n} is not specified.
+
+@subsection Opening File Descriptors for Reading and Writing
+The redirection operator
+@example
+[@var{n}]<>@var{word}
+@end example
+@noindent
+causes the file whose name is the expansion of @var{word}
+to be opened for both reading and writing on file descriptor
+@var{n}, or on file descriptor 0 if @var{n}
+is not specified. If the file does not exist, it is created.
+
+@node Executing Commands
+@section Executing Commands
+
+@menu
+* Simple Command Expansion:: How Bash expands simple commands before
+ executing them.
+* Command Search and Execution:: How Bash finds commands and runs them.
+* Command Execution Environment:: The environment in which Bash
+ executes commands that are not
+ shell builtins.
+* Environment:: The environment given to a command.
+* Exit Status:: The status returned by commands and how Bash
+ interprets it.
+* Signals:: What happens when Bash or a command it runs
+ receives a signal.
+@end menu
+
+@node Simple Command Expansion
+@subsection Simple Command Expansion
+@cindex command expansion
+
+When a simple command is executed, the shell performs the following
+expansions, assignments, and redirections, from left to right.
+
+@enumerate
+@item
+The words that the parser has marked as variable assignments (those
+preceding the command name) and redirections are saved for later
+processing.
+
+@item
+The words that are not variable assignments or redirections are
+expanded (@pxref{Shell Expansions}).
+If any words remain after expansion, the first word
+is taken to be the name of the command and the remaining words are
+the arguments.
+
+@item
+Redirections are performed as described above (@pxref{Redirections}).
+
+@item
+The text after the @samp{=} in each variable assignment undergoes tilde
+expansion, parameter expansion, command substitution, arithmetic expansion,
+and quote removal before being assigned to the variable.
+@end enumerate
+
+If no command name results, the variable assignments affect the current
+shell environment. Otherwise, the variables are added to the environment
+of the executed command and do not affect the current shell environment.
+If any of the assignments attempts to assign a value to a readonly variable,
+an error occurs, and the command exits with a non-zero status.
+
+If no command name results, redirections are performed, but do not
+affect the current shell environment. A redirection error causes the
+command to exit with a non-zero status.
+
+If there is a command name left after expansion, execution proceeds as
+described below. Otherwise, the command exits. If one of the expansions
+contained a command substitution, the exit status of the command is
+the exit status of the last command substitution performed. If there
+were no command substitutions, the command exits with a status of zero.
+
+@node Command Search and Execution
+@subsection Command Search and Execution
+@cindex command execution
+@cindex command search
+
+After a command has been split into words, if it results in a
+simple command and an optional list of arguments, the following
+actions are taken.
+
+@enumerate
+@item
+If the command name contains no slashes, the shell attempts to
+locate it. If there exists a shell function by that name, that
+function is invoked as described in @ref{Shell Functions}.
+
+@item
+If the name does not match a function, the shell searches for
+it in the list of shell builtins. If a match is found, that
+builtin is invoked.
+
+@item
+If the name is neither a shell function nor a builtin,
+and contains no slashes, Bash searches each element of
+@env{$PATH} for a directory containing an executable file
+by that name. Bash uses a hash table to remember the full
+pathnames of executable files to avoid multiple @env{PATH} searches
+(see the description of @code{hash} in @ref{Bourne Shell Builtins}).
+A full search of the directories in @env{$PATH}
+is performed only if the command is not found in the hash table.
+If the search is unsuccessful, the shell searches for a defined shell
+function named @code{command_not_found_handle}.
+If that function exists, it is invoked with the original command and
+the original command's arguments as its arguments, and the function's
+exit status becomes the exit status of the shell.
+If that function is not defined, the shell prints an error
+message and returns an exit status of 127.
+
+@item
+If the search is successful, or if the command name contains
+one or more slashes, the shell executes the named program in
+a separate execution environment.
+Argument 0 is set to the name given, and the remaining arguments
+to the command are set to the arguments supplied, if any.
+
+@item
+If this execution fails because the file is not in executable
+format, and the file is not a directory, it is assumed to be a
+@var{shell script} and the shell executes it as described in
+@ref{Shell Scripts}.
+
+@item
+If the command was not begun asynchronously, the shell waits for
+the command to complete and collects its exit status.
+
+@end enumerate
+
+@node Command Execution Environment
+@subsection Command Execution Environment
+@cindex execution environment
+
+The shell has an @var{execution environment}, which consists of the
+following:
+
+@itemize @bullet
+@item
+open files inherited by the shell at invocation, as modified by
+redirections supplied to the @code{exec} builtin
+
+@item
+the current working directory as set by @code{cd}, @code{pushd}, or
+@code{popd}, or inherited by the shell at invocation
+
+@item
+the file creation mode mask as set by @code{umask} or inherited from
+the shell's parent
+
+@item
+current traps set by @code{trap}
+
+@item
+shell parameters that are set by variable assignment or with @code{set}
+or inherited from the shell's parent in the environment
+
+@item
+shell functions defined during execution or inherited from the shell's
+parent in the environment
+
+@item
+options enabled at invocation (either by default or with command-line
+arguments) or by @code{set}
+
+@item
+options enabled by @code{shopt} (@pxref{The Shopt Builtin})
+
+@item
+shell aliases defined with @code{alias} (@pxref{Aliases})
+
+@item
+various process @sc{id}s, including those of background jobs
+(@pxref{Lists}), the value of @code{$$}, and the value of
+@env{$PPID}
+
+@end itemize
+
+When a simple command other than a builtin or shell function
+is to be executed, it
+is invoked in a separate execution environment that consists of
+the following. Unless otherwise noted, the values are inherited
+from the shell.
+
+@itemize @bullet
+@item
+the shell's open files, plus any modifications and additions specified
+by redirections to the command
+
+@item
+the current working directory
+
+@item
+the file creation mode mask
+
+@item
+shell variables and functions marked for export, along with variables
+exported for the command, passed in the environment (@pxref{Environment})
+
+@item
+traps caught by the shell are reset to the values inherited from the
+shell's parent, and traps ignored by the shell are ignored
+
+@end itemize
+
+A command invoked in this separate environment cannot affect the
+shell's execution environment.
+
+Command substitution, commands grouped with parentheses,
+and asynchronous commands are invoked in a
+subshell environment that is a duplicate of the shell environment,
+except that traps caught by the shell are reset to the values
+that the shell inherited from its parent at invocation. Builtin
+commands that are invoked as part of a pipeline are also executed
+in a subshell environment. Changes made to the subshell environment
+cannot affect the shell's execution environment.
+
+Subshells spawned to execute command substitutions inherit the value of
+the @option{-e} option from the parent shell. When not in @sc{posix} mode,
+Bash clears the @option{-e} option in such subshells.
+
+If a command is followed by a @samp{&} and job control is not active, the
+default standard input for the command is the empty file @file{/dev/null}.
+Otherwise, the invoked command inherits the file descriptors of the calling
+shell as modified by redirections.
+
+@node Environment
+@subsection Environment
+@cindex environment
+
+When a program is invoked it is given an array of strings
+called the @var{environment}.
+This is a list of name-value pairs, of the form @code{name=value}.
+
+Bash provides several ways to manipulate the environment.
+On invocation, the shell scans its own environment and
+creates a parameter for each name found, automatically marking
+it for @var{export}
+to child processes. Executed commands inherit the environment.
+The @code{export} and @samp{declare -x}
+commands allow parameters and functions to be added to and
+deleted from the environment. If the value of a parameter
+in the environment is modified, the new value becomes part
+of the environment, replacing the old. The environment
+inherited by any executed command consists of the shell's
+initial environment, whose values may be modified in the shell,
+less any pairs removed by the @code{unset} and @samp{export -n}
+commands, plus any additions via the @code{export} and
+@samp{declare -x} commands.
+
+The environment for any simple command
+or function may be augmented temporarily by prefixing it with
+parameter assignments, as described in @ref{Shell Parameters}.
+These assignment statements affect only the environment seen
+by that command.
+
+If the @option{-k} option is set (@pxref{The Set Builtin}), then all
+parameter assignments are placed in the environment for a command,
+not just those that precede the command name.
+
+When Bash invokes an external command, the variable @samp{$_}
+is set to the full pathname of the command and passed to that
+command in its environment.
+
+@node Exit Status
+@subsection Exit Status
+@cindex exit status
+
+The exit status of an executed command is the value returned by the
+@var{waitpid} system call or equivalent function. Exit statuses
+fall between 0 and 255, though, as explained below, the shell may
+use values above 125 specially. Exit statuses from shell builtins and
+compound commands are also limited to this range. Under certain
+circumstances, the shell will use special values to indicate specific
+failure modes.
+
+For the shell's purposes, a command which exits with a
+zero exit status has succeeded.
+A non-zero exit status indicates failure.
+This seemingly counter-intuitive scheme is used so there
+is one well-defined way to indicate success and a variety of
+ways to indicate various failure modes.
+When a command terminates on a fatal signal whose number is @var{N},
+Bash uses the value 128+@var{N} as the exit status.
+
+If a command is not found, the child process created to
+execute it returns a status of 127. If a command is found
+but is not executable, the return status is 126.
+
+If a command fails because of an error during expansion or redirection,
+the exit status is greater than zero.
+
+The exit status is used by the Bash conditional commands
+(@pxref{Conditional Constructs}) and some of the list
+constructs (@pxref{Lists}).
+
+All of the Bash builtins return an exit status of zero if they succeed
+and a non-zero status on failure, so they may be used by the
+conditional and list constructs.
+All builtins return an exit status of 2 to indicate incorrect usage,
+generally invalid options or missing arguments.
+
+@node Signals
+@subsection Signals
+@cindex signal handling
+
+When Bash is interactive, in the absence of any traps, it ignores
+@code{SIGTERM} (so that @samp{kill 0} does not kill an interactive shell),
+and @code{SIGINT}
+is caught and handled (so that the @code{wait} builtin is interruptible).
+When Bash receives a @code{SIGINT}, it breaks out of any executing loops.
+In all cases, Bash ignores @code{SIGQUIT}.
+If job control is in effect (@pxref{Job Control}), Bash
+ignores @code{SIGTTIN}, @code{SIGTTOU}, and @code{SIGTSTP}.
+
+Non-builtin commands started by Bash have signal handlers set to the
+values inherited by the shell from its parent.
+When job control is not in effect, asynchronous commands
+ignore @code{SIGINT} and @code{SIGQUIT} in addition to these inherited
+handlers.
+Commands run as a result of
+command substitution ignore the keyboard-generated job control signals
+@code{SIGTTIN}, @code{SIGTTOU}, and @code{SIGTSTP}.
+
+The shell exits by default upon receipt of a @code{SIGHUP}.
+Before exiting, an interactive shell resends the @code{SIGHUP} to
+all jobs, running or stopped.
+Stopped jobs are sent @code{SIGCONT} to ensure that they receive
+the @code{SIGHUP}.
+To prevent the shell from sending the @code{SIGHUP} signal to a
+particular job, it should be removed
+from the jobs table with the @code{disown}
+builtin (@pxref{Job Control Builtins}) or marked
+to not receive @code{SIGHUP} using @code{disown -h}.
+
+If the @code{huponexit} shell option has been set with @code{shopt}
+(@pxref{The Shopt Builtin}), Bash sends a @code{SIGHUP} to all jobs when
+an interactive login shell exits.
+
+If Bash is waiting for a command to complete and receives a signal
+for which a trap has been set, the trap will not be executed until
+the command completes.
+When Bash is waiting for an asynchronous
+command via the @code{wait} builtin, the reception of a signal for
+which a trap has been set will cause the @code{wait} builtin to return
+immediately with an exit status greater than 128, immediately after
+which the trap is executed.
+
+@node Shell Scripts
+@section Shell Scripts
+@cindex shell script
+
+A shell script is a text file containing shell commands. When such
+a file is used as the first non-option argument when invoking Bash,
+and neither the @option{-c} nor @option{-s} option is supplied
+(@pxref{Invoking Bash}),
+Bash reads and executes commands from the file, then exits. This
+mode of operation creates a non-interactive shell. The shell first
+searches for the file in the current directory, and looks in the
+directories in @env{$PATH} if not found there.
+
+When Bash runs
+a shell script, it sets the special parameter @code{0} to the name
+of the file, rather than the name of the shell, and the positional
+parameters are set to the remaining arguments, if any are given.
+If no additional arguments are supplied, the positional parameters
+are unset.
+
+A shell script may be made executable by using the @code{chmod} command
+to turn on the execute bit. When Bash finds such a file while
+searching the @env{$PATH} for a command, it spawns a subshell to
+execute it. In other words, executing
+@example
+filename @var{arguments}
+@end example
+@noindent
+is equivalent to executing
+@example
+bash filename @var{arguments}
+@end example
+
+@noindent
+if @code{filename} is an executable shell script.
+This subshell reinitializes itself, so that the effect is as if a
+new shell had been invoked to interpret the script, with the
+exception that the locations of commands remembered by the parent
+(see the description of @code{hash} in @ref{Bourne Shell Builtins})
+are retained by the child.
+
+Most versions of Unix make this a part of the operating system's command
+execution mechanism. If the first line of a script begins with
+the two characters @samp{#!}, the remainder of the line specifies
+an interpreter for the program.
+Thus, you can specify Bash, @code{awk}, Perl, or some other
+interpreter and write the rest of the script file in that language.
+
+The arguments to the interpreter
+consist of a single optional argument following the interpreter
+name on the first line of the script file, followed by the name of
+the script file, followed by the rest of the arguments. Bash
+will perform this action on operating systems that do not handle it
+themselves. Note that some older versions of Unix limit the interpreter
+name and argument to a maximum of 32 characters.
+
+Bash scripts often begin with @code{#! /bin/bash} (assuming that
+Bash has been installed in @file{/bin}), since this ensures that
+Bash will be used to interpret the script, even if it is executed
+under another shell.
+
+@node Shell Builtin Commands
+@chapter Shell Builtin Commands
+
+@menu
+* Bourne Shell Builtins:: Builtin commands inherited from the Bourne
+ Shell.
+* Bash Builtins:: Table of builtins specific to Bash.
+* Modifying Shell Behavior:: Builtins to modify shell attributes and
+ optional behavior.
+* Special Builtins:: Builtin commands classified specially by
+ POSIX.
+@end menu
+
+Builtin commands are contained within the shell itself.
+When the name of a builtin command is used as the first word of
+a simple command (@pxref{Simple Commands}), the shell executes
+the command directly, without invoking another program.
+Builtin commands are necessary to implement functionality impossible
+or inconvenient to obtain with separate utilities.
+
+This section briefly describes the builtins which Bash inherits from
+the Bourne Shell, as well as the builtin commands which are unique
+to or have been extended in Bash.
+
+Several builtin commands are described in other chapters: builtin
+commands which provide the Bash interface to the job control
+facilities (@pxref{Job Control Builtins}), the directory stack
+(@pxref{Directory Stack Builtins}), the command history
+(@pxref{Bash History Builtins}), and the programmable completion
+facilities (@pxref{Programmable Completion Builtins}).
+
+Many of the builtins have been extended by @sc{posix} or Bash.
+
+Unless otherwise noted, each builtin command documented as accepting
+options preceded by @samp{-} accepts @samp{--}
+to signify the end of the options.
+The @code{:}, @code{true}, @code{false}, and @code{test}
+builtins do not accept options and do not treat @samp{--} specially.
+The @code{exit}, @code{logout}, @code{break}, @code{continue}, @code{let},
+and @code{shift} builtins accept and process arguments beginning
+with @samp{-} without requiring @samp{--}.
+Other builtins that accept arguments but are not specified as accepting
+options interpret arguments beginning with @samp{-} as invalid options and
+require @samp{--} to prevent this interpretation.
+
+@node Bourne Shell Builtins
+@section Bourne Shell Builtins
+
+The following shell builtin commands are inherited from the Bourne Shell.
+These commands are implemented as specified by the @sc{posix} standard.
+
+@table @code
+@item : @r{(a colon)}
+@btindex :
+@example
+: [@var{arguments}]
+@end example
+
+Do nothing beyond expanding @var{arguments} and performing redirections.
+The return status is zero.
+
+@item . @r{(a period)}
+@btindex .
+@example
+. @var{filename} [@var{arguments}]
+@end example
+
+Read and execute commands from the @var{filename} argument in the
+current shell context. If @var{filename} does not contain a slash,
+the @env{PATH} variable is used to find @var{filename}.
+When Bash is not in @sc{posix} mode, the current directory is searched
+if @var{filename} is not found in @env{$PATH}.
+If any @var{arguments} are supplied, they become the positional
+parameters when @var{filename} is executed. Otherwise the positional
+parameters are unchanged.
+The return status is the exit status of the last command executed, or
+zero if no commands are executed. If @var{filename} is not found, or
+cannot be read, the return status is non-zero.
+This builtin is equivalent to @code{source}.
+
+@item break
+@btindex break
+@example
+break [@var{n}]
+@end example
+
+Exit from a @code{for}, @code{while}, @code{until}, or @code{select} loop.
+If @var{n} is supplied, the @var{n}th enclosing loop is exited.
+@var{n} must be greater than or equal to 1.
+The return status is zero unless @var{n} is not greater than or equal to 1.
+
+@item cd
+@btindex cd
+@example
+cd [-L|[-P [-e]] [-@@] [@var{directory}]
+@end example
+
+Change the current working directory to @var{directory}.
+If @var{directory} is not supplied, the value of the @env{HOME}
+shell variable is used.
+Any additional arguments following @var{directory} are ignored.
+If the shell variable
+@env{CDPATH} exists, it is used as a search path:
+each directory name in @env{CDPATH} is searched for
+@var{directory}, with alternative directory names in @env{CDPATH}
+separated by a colon (@samp{:}).
+If @var{directory} begins with a slash, @env{CDPATH} is not used.
+
+The @option{-P} option means to not follow symbolic links: symbolic links
+are resolved while @code{cd} is traversing @var{directory} and before
+processing an instance of @samp{..} in @var{directory}.
+
+By default, or when the @option{-L} option is supplied, symbolic links
+in @var{directory} are resolved after @code{cd} processes an instance
+of @samp{..} in @var{directory}.
+
+If @samp{..} appears in @var{directory}, it is processed by removing the
+immediately preceding pathname component, back to a slash or the beginning
+of @var{directory}.
+
+If the @option{-e} option is supplied with @option{-P}
+and the current working directory cannot be successfully determined
+after a successful directory change, @code{cd} will return an unsuccessful
+status.
+
+On systems that support it, the @option{-@@} option presents the extended
+attributes associated with a file as a directory.
+
+If @var{directory} is @samp{-}, it is converted to @env{$OLDPWD}
+before the directory change is attempted.
+
+If a non-empty directory name from @env{CDPATH} is used, or if
+@samp{-} is the first argument, and the directory change is
+successful, the absolute pathname of the new working directory is
+written to the standard output.
+
+The return status is zero if the directory is successfully changed,
+non-zero otherwise.
+
+@item continue
+@btindex continue
+@example
+continue [@var{n}]
+@end example
+
+Resume the next iteration of an enclosing @code{for}, @code{while},
+@code{until}, or @code{select} loop.
+If @var{n} is supplied, the execution of the @var{n}th enclosing loop
+is resumed.
+@var{n} must be greater than or equal to 1.
+The return status is zero unless @var{n} is not greater than or equal to 1.
+
+@item eval
+@btindex eval
+@example
+eval [@var{arguments}]
+@end example
+
+The arguments are concatenated together into a single command, which is
+then read and executed, and its exit status returned as the exit status
+of @code{eval}.
+If there are no arguments or only empty arguments, the return status is
+zero.
+
+@item exec
+@btindex exec
+@example
+exec [-cl] [-a @var{name}] [@var{command} [@var{arguments}]]
+@end example
+
+If @var{command}
+is supplied, it replaces the shell without creating a new process.
+If the @option{-l} option is supplied, the shell places a dash at the
+beginning of the zeroth argument passed to @var{command}.
+This is what the @code{login} program does.
+The @option{-c} option causes @var{command} to be executed with an empty
+environment.
+If @option{-a} is supplied, the shell passes @var{name} as the zeroth
+argument to @var{command}.
+If @var{command}
+cannot be executed for some reason, a non-interactive shell exits,
+unless the @code{execfail} shell option
+is enabled. In that case, it returns failure.
+An interactive shell returns failure if the file cannot be executed.
+If no @var{command} is specified, redirections may be used to affect
+the current shell environment. If there are no redirection errors, the
+return status is zero; otherwise the return status is non-zero.
+
+@item exit
+@btindex exit
+@example
+exit [@var{n}]
+@end example
+
+Exit the shell, returning a status of @var{n} to the shell's parent.
+If @var{n} is omitted, the exit status is that of the last command executed.
+Any trap on @code{EXIT} is executed before the shell terminates.
+
+@item export
+@btindex export
+@example
+export [-fn] [-p] [@var{name}[=@var{value}]]
+@end example
+
+Mark each @var{name} to be passed to child processes
+in the environment. If the @option{-f} option is supplied, the @var{name}s
+refer to shell functions; otherwise the names refer to shell variables.
+The @option{-n} option means to no longer mark each @var{name} for export.
+If no @var{names} are supplied, or if the @option{-p} option is given, a
+list of names of all exported variables is displayed.
+The @option{-p} option displays output in a form that may be reused as input.
+If a variable name is followed by =@var{value}, the value of
+the variable is set to @var{value}.
+
+The return status is zero unless an invalid option is supplied, one of
+the names is not a valid shell variable name, or @option{-f} is supplied
+with a name that is not a shell function.
+
+@item getopts
+@btindex getopts
+@example
+getopts @var{optstring} @var{name} [@var{args}]
+@end example
+
+@code{getopts} is used by shell scripts to parse positional parameters.
+@var{optstring} contains the option characters to be recognized; if a
+character is followed by a colon, the option is expected to have an
+argument, which should be separated from it by whitespace.
+The colon (@samp{:}) and question mark (@samp{?}) may not be
+used as option characters.
+Each time it is invoked, @code{getopts}
+places the next option in the shell variable @var{name}, initializing
+@var{name} if it does not exist,
+and the index of the next argument to be processed into the
+variable @env{OPTIND}.
+@env{OPTIND} is initialized to 1 each time the shell or a shell script
+is invoked.
+When an option requires an argument,
+@code{getopts} places that argument into the variable @env{OPTARG}.
+The shell does not reset @env{OPTIND} automatically; it must be manually
+reset between multiple calls to @code{getopts} within the same shell
+invocation if a new set of parameters is to be used.
+
+When the end of options is encountered, @code{getopts} exits with a
+return value greater than zero.
+@env{OPTIND} is set to the index of the first non-option argument,
+and @var{name} is set to @samp{?}.
+
+@code{getopts}
+normally parses the positional parameters, but if more arguments are
+given in @var{args}, @code{getopts} parses those instead.
+
+@code{getopts} can report errors in two ways. If the first character of
+@var{optstring} is a colon, @var{silent}
+error reporting is used. In normal operation, diagnostic messages
+are printed when invalid options or missing option arguments are
+encountered.
+If the variable @env{OPTERR}
+is set to 0, no error messages will be displayed, even if the first
+character of @code{optstring} is not a colon.
+
+If an invalid option is seen,
+@code{getopts} places @samp{?} into @var{name} and, if not silent,
+prints an error message and unsets @env{OPTARG}.
+If @code{getopts} is silent, the option character found is placed in
+@env{OPTARG} and no diagnostic message is printed.
+
+If a required argument is not found, and @code{getopts}
+is not silent, a question mark (@samp{?}) is placed in @var{name},
+@code{OPTARG} is unset, and a diagnostic message is printed.
+If @code{getopts} is silent, then a colon (@samp{:}) is placed in
+@var{name} and @env{OPTARG} is set to the option character found.
+
+@item hash
+@btindex hash
+@example
+hash [-r] [-p @var{filename}] [-dt] [@var{name}]
+@end example
+
+Each time @code{hash} is invoked, it remembers the full pathnames of the
+commands specified as @var{name} arguments,
+so they need not be searched for on subsequent invocations.
+The commands are found by searching through the directories listed in
+@env{$PATH}.
+Any previously-remembered pathname is discarded.
+The @option{-p} option inhibits the path search, and @var{filename} is
+used as the location of @var{name}.
+The @option{-r} option causes the shell to forget all remembered locations.
+The @option{-d} option causes the shell to forget the remembered location
+of each @var{name}.
+If the @option{-t} option is supplied, the full pathname to which each
+@var{name} corresponds is printed. If multiple @var{name} arguments are
+supplied with @option{-t} the @var{name} is printed before the hashed
+full pathname.
+The @option{-l} option causes output to be displayed in a format
+that may be reused as input.
+If no arguments are given, or if only @option{-l} is supplied,
+information about remembered commands is printed.
+The return status is zero unless a @var{name} is not found or an invalid
+option is supplied.
+
+@item pwd
+@btindex pwd
+@example
+pwd [-LP]
+@end example
+
+Print the absolute pathname of the current working directory.
+If the @option{-P} option is supplied, the pathname printed will not
+contain symbolic links.
+If the @option{-L} option is supplied, the pathname printed may contain
+symbolic links.
+The return status is zero unless an error is encountered while
+determining the name of the current directory or an invalid option
+is supplied.
+
+@item readonly
+@btindex readonly
+@example
+readonly [-aAf] [-p] [@var{name}[=@var{value}]] @dots{}
+@end example
+
+Mark each @var{name} as readonly.
+The values of these names may not be changed by subsequent assignment.
+If the @option{-f} option is supplied, each @var{name} refers to a shell
+function.
+The @option{-a} option means each @var{name} refers to an indexed
+array variable; the @option{-A} option means each @var{name} refers
+to an associative array variable.
+If both options are supplied, @option{-A} takes precedence.
+If no @var{name} arguments are given, or if the @option{-p}
+option is supplied, a list of all readonly names is printed.
+The other options may be used to restrict the output to a subset of
+the set of readonly names.
+The @option{-p} option causes output to be displayed in a format that
+may be reused as input.
+If a variable name is followed by =@var{value}, the value of
+the variable is set to @var{value}.
+The return status is zero unless an invalid option is supplied, one of
+the @var{name} arguments is not a valid shell variable or function name,
+or the @option{-f} option is supplied with a name that is not a shell function.
+
+@item return
+@btindex return
+@example
+return [@var{n}]
+@end example
+
+Cause a shell function to stop executing and return the value @var{n}
+to its caller.
+If @var{n} is not supplied, the return value is the exit status of the
+last command executed in the function.
+If @code{return} is executed by a trap handler, the last command used to
+determine the status is the last command executed before the trap handler.
+if @code{return} is executed during a @code{DEBUG} trap, the last command
+used to determine the status is the last command executed by the trap
+handler before @code{return} was invoked.
+@code{return} may also be used to terminate execution of a script
+being executed with the @code{.} (@code{source}) builtin,
+returning either @var{n} or
+the exit status of the last command executed within the script as the exit
+status of the script.
+If @var{n} is supplied, the return value is its least significant
+8 bits.
+Any command associated with the @code{RETURN} trap is executed
+before execution resumes after the function or script.
+The return status is non-zero if @code{return} is supplied a non-numeric
+argument or is used outside a function
+and not during the execution of a script by @code{.} or @code{source}.
+
+@item shift
+@btindex shift
+@example
+shift [@var{n}]
+@end example
+
+Shift the positional parameters to the left by @var{n}.
+The positional parameters from @var{n}+1 @dots{} @code{$#} are
+renamed to @code{$1} @dots{} @code{$#}-@var{n}.
+Parameters represented by the numbers @code{$#} to @code{$#}-@var{n}+1
+are unset.
+@var{n} must be a non-negative number less than or equal to @code{$#}.
+If @var{n} is zero or greater than @code{$#}, the positional parameters
+are not changed.
+If @var{n} is not supplied, it is assumed to be 1.
+The return status is zero unless @var{n} is greater than @code{$#} or
+less than zero, non-zero otherwise.
+
+@item test
+@itemx [
+@btindex test
+@btindex [
+@example
+test @var{expr}
+@end example
+
+Evaluate a conditional express
+ion @var{expr} and return a status of 0
+(true) or 1 (false).
+Each operator and operand must be a separate argument.
+Expressions are composed of the primaries described below in
+@ref{Bash Conditional Expressions}.
+@code{test} does not accept any options, nor does it accept and ignore
+an argument of @option{--} as signifying the end of options.
+
+When the @code{[} form is used, the last argument to the command must
+be a @code{]}.
+
+Expressions may be combined using the following operators, listed in
+decreasing order of precedence.
+The evaluation depends on the number of arguments; see below.
+Operator precedence is used when there are five or more arguments.
+
+@table @code
+@item ! @var{expr}
+True if @var{expr} is false.
+
+@item ( @var{expr} )
+Returns the value of @var{expr}.
+This may be used to override the normal precedence of operators.
+
+@item @var{expr1} -a @var{expr2}
+True if both @var{expr1} and @var{expr2} are true.
+
+@item @var{expr1} -o @var{expr2}
+True if either @var{expr1} or @var{expr2} is true.
+@end table
+
+The @code{test} and @code{[} builtins evaluate conditional
+expressions using a set of rules based on the number of arguments.
+
+@table @asis
+@item 0 arguments
+The expression is false.
+
+@item 1 argument
+The expression is true if and only if the argument is not null.
+
+@item 2 arguments
+If the first argument is @samp{!}, the expression is true if and
+only if the second argument is null.
+If the first argument is one of the unary conditional operators
+(@pxref{Bash Conditional Expressions}), the expression
+is true if the unary test is true.
+If the first argument is not a valid unary operator, the expression is
+false.
+
+@item 3 arguments
+The following conditions are applied in the order listed.
+If the second argument is one of the binary conditional
+operators (@pxref{Bash Conditional Expressions}), the
+result of the expression is the result of the binary test using the
+first and third arguments as operands.
+The @samp{-a} and @samp{-o} operators are considered binary operators
+when there are three arguments.
+If the first argument is @samp{!}, the value is the negation of
+the two-argument test using the second and third arguments.
+If the first argument is exactly @samp{(} and the third argument is
+exactly @samp{)}, the result is the one-argument test of the second
+argument.
+Otherwise, the expression is false.
+
+@item 4 arguments
+If the first argument is @samp{!}, the result is the negation of
+the three-argument expression composed of the remaining arguments.
+Otherwise, the expression is parsed and evaluated according to
+precedence using the rules listed above.
+
+@item 5 or more arguments
+The expression is parsed and evaluated according to precedence
+using the rules listed above.
+@end table
+
+When used with @code{test} or @samp{[}, the @samp{<} and @samp{>}
+operators sort lexicographically using ASCII ordering.
+
+@item times
+@btindex times
+@example
+times
+@end example
+
+Print out the user and system times used by the shell and its children.
+The return status is zero.
+
+@item trap
+@btindex trap
+@example
+trap [-lp] [@var{arg}] [@var{sigspec} @dots{}]
+@end example
+
+The commands in @var{arg} are to be read and executed when the
+shell receives signal @var{sigspec}. If @var{arg} is absent (and
+there is a single @var{sigspec}) or
+equal to @samp{-}, each specified signal's disposition is reset
+to the value it had when the shell was started.
+If @var{arg} is the null string, then the signal specified by
+each @var{sigspec} is ignored by the shell and commands it invokes.
+If @var{arg} is not present and @option{-p} has been supplied,
+the shell displays the trap commands associated with each @var{sigspec}.
+If no arguments are supplied, or
+only @option{-p} is given, @code{trap} prints the list of commands
+associated with each signal number in a form that may be reused as
+shell input.
+The @option{-l} option causes the shell to print a list of signal names
+and their corresponding numbers.
+Each @var{sigspec} is either a signal name or a signal number.
+Signal names are case insensitive and the @code{SIG} prefix is optional.
+
+If a @var{sigspec}
+is @code{0} or @code{EXIT}, @var{arg} is executed when the shell exits.
+If a @var{sigspec} is @code{DEBUG}, the command @var{arg} is executed
+before every simple command, @code{for} command, @code{case} command,
+@code{select} command, every arithmetic @code{for} command, and before
+the first command executes in a shell function.
+Refer to the description of the @code{extdebug} option to the
+@code{shopt} builtin (@pxref{The Shopt Builtin}) for details of its
+effect on the @code{DEBUG} trap.
+If a @var{sigspec} is @code{RETURN}, the command @var{arg} is executed
+each time a shell function or a script executed with the @code{.} or
+@code{source} builtins finishes executing.
+
+If a @var{sigspec} is @code{ERR}, the command @var{arg}
+is executed whenever
+a pipeline (which may consist of a single simple
+command), a list, or a compound command returns a
+non-zero exit status,
+subject to the following conditions.
+The @code{ERR} trap is not executed if the failed command is part of the
+command list immediately following an @code{until} or @code{while} keyword,
+part of the test following the @code{if} or @code{elif} reserved words,
+part of a command executed in a @code{&&} or @code{||} list
+except the command following the final @code{&&} or @code{||},
+any command in a pipeline but the last,
+or if the command's return
+status is being inverted using @code{!}.
+These are the same conditions obeyed by the @code{errexit} (@option{-e})
+option.
+
+Signals ignored upon entry to the shell cannot be trapped or reset.
+Trapped signals that are not being ignored are reset to their original
+values in a subshell or subshell environment when one is created.
+
+The return status is zero unless a @var{sigspec} does not specify a
+valid signal.
+
+@item umask
+@btindex umask
+@example
+umask [-p] [-S] [@var{mode}]
+@end example
+
+Set the shell process's file creation mask to @var{mode}. If
+@var{mode} begins with a digit, it is interpreted as an octal number;
+if not, it is interpreted as a symbolic mode mask similar
+to that accepted by the @code{chmod} command. If @var{mode} is
+omitted, the current value of the mask is printed. If the @option{-S}
+option is supplied without a @var{mode} argument, the mask is printed
+in a symbolic format.
+If the @option{-p} option is supplied, and @var{mode}
+is omitted, the output is in a form that may be reused as input.
+The return status is zero if the mode is successfully changed or if
+no @var{mode} argument is supplied, and non-zero otherwise.
+
+Note that when the mode is interpreted as an octal number, each number
+of the umask is subtracted from @code{7}. Thus, a umask of @code{022}
+results in permissions of @code{755}.
+
+@item unset
+@btindex unset
+@example
+unset [-fnv] [@var{name}]
+@end example
+
+Remove each variable or function @var{name}.
+If the @option{-v} option is given, each
+@var{name} refers to a shell variable and that variable is remvoved.
+If the @option{-f} option is given, the @var{name}s refer to shell
+functions, and the function definition is removed.
+If the @option{-n} option is supplied, and @var{name} is a variable with
+the @var{nameref} attribute, @var{name} will be unset rather than the
+variable it references.
+@option{-n} has no effect if the @option{-f} option is supplied.
+If no options are supplied, each @var{name} refers to a variable; if
+there is no variable by that name, any function with that name is
+unset.
+Readonly variables and functions may not be unset.
+The return status is zero unless a @var{name} is readonly.
+@end table
+
+@node Bash Builtins
+@section Bash Builtin Commands
+
+This section describes builtin commands which are unique to
+or have been extended in Bash.
+Some of these commands are specified in the @sc{posix} standard.
+
+@table @code
+
+@item alias
+@btindex alias
+@example
+alias [-p] [@var{name}[=@var{value}] @dots{}]
+@end example
+
+Without arguments or with the @option{-p} option, @code{alias} prints
+the list of aliases on the standard output in a form that allows
+them to be reused as input.
+If arguments are supplied, an alias is defined for each @var{name}
+whose @var{value} is given. If no @var{value} is given, the name
+and value of the alias is printed.
+Aliases are described in @ref{Aliases}.
+
+@item bind
+@btindex bind
+@example
+bind [-m @var{keymap}] [-lpsvPSVX]
+bind [-m @var{keymap}] [-q @var{function}] [-u @var{function}] [-r @var{keyseq}]
+bind [-m @var{keymap}] -f @var{filename}
+bind [-m @var{keymap}] -x @var{keyseq:shell-command}
+bind [-m @var{keymap}] @var{keyseq:function-name}
+bind [-m @var{keymap}] @var{keyseq:readline-command}
+@end example
+
+Display current Readline (@pxref{Command Line Editing})
+key and function bindings,
+bind a key sequence to a Readline function or macro,
+or set a Readline variable.
+Each non-option argument is a command as it would appear in a
+Readline initialization file (@pxref{Readline Init File}),
+but each binding or command must be passed as a separate argument; e.g.,
+@samp{"\C-x\C-r":re-read-init-file}.
+
+Options, if supplied, have the following meanings:
+
+@table @code
+@item -m @var{keymap}
+Use @var{keymap} as the keymap to be affected by
+the subsequent bindings. Acceptable @var{keymap}
+names are
+@code{emacs},
+@code{emacs-standard},
+@code{emacs-meta},
+@code{emacs-ctlx},
+@code{vi},
+@code{vi-move},
+@code{vi-command}, and
+@code{vi-insert}.
+@code{vi} is equivalent to @code{vi-command};
+@code{emacs} is equivalent to @code{emacs-standard}.
+
+@item -l
+List the names of all Readline functions.
+
+@item -p
+Display Readline function names and bindings in such a way that they
+can be used as input or in a Readline initialization file.
+
+@item -P
+List current Readline function names and bindings.
+
+@item -v
+Display Readline variable names and values in such a way that they
+can be used as input or in a Readline initialization file.
+
+@item -V
+List current Readline variable names and values.
+
+@item -s
+Display Readline key sequences bound to macros and the strings they output
+in such a way that they can be used as input or in a Readline
+initialization file.
+
+@item -S
+Display Readline key sequences bound to macros and the strings they output.
+
+@item -f @var{filename}
+Read key bindings from @var{filename}.
+
+@item -q @var{function}
+Query about which keys invoke the named @var{function}.
+
+@item -u @var{function}
+Unbind all keys bound to the named @var{function}.
+
+@item -r @var{keyseq}
+Remove any current binding for @var{keyseq}.
+
+@item -x @var{keyseq:shell-command}
+Cause @var{shell-command} to be executed whenever @var{keyseq} is
+entered.
+When @var{shell-command} is executed, the shell sets the
+@code{READLINE_LINE} variable to the contents of the Readline line
+buffer and the @code{READLINE_POINT} variable to the current location
+of the insertion point.
+If the executed command changes the value of @code{READLINE_LINE} or
+@code{READLINE_POINT}, those new values will be reflected in the
+editing state.
+
+@item -X
+List all key sequences bound to shell commands and the associated commands
+in a format that can be reused as input.
+@end table
+
+@noindent
+The return status is zero unless an invalid option is supplied or an
+error occurs.
+
+@item builtin
+@btindex builtin
+@example
+builtin [@var{shell-builtin} [@var{args}]]
+@end example
+
+Run a shell builtin, passing it @var{args}, and return its exit status.
+This is useful when defining a shell function with the same
+name as a shell builtin, retaining the functionality of the builtin within
+the function.
+The return status is non-zero if @var{shell-builtin} is not a shell
+builtin command.
+
+@item caller
+@btindex caller
+@example
+caller [@var{expr}]
+@end example
+
+Returns the context of any active subroutine call (a shell function or
+a script executed with the @code{.} or @code{source} builtins).
+
+Without @var{expr}, @code{caller} displays the line number and source
+filename of the current subroutine call.
+If a non-negative integer is supplied as @var{expr}, @code{caller}
+displays the line number, subroutine name, and source file corresponding
+to that position in the current execution call stack. This extra
+information may be used, for example, to print a stack trace. The
+current frame is frame 0.
+
+The return value is 0 unless the shell is not executing a subroutine
+call or @var{expr} does not correspond to a valid position in the
+call stack.
+
+@item command
+@btindex command
+@example
+command [-pVv] @var{command} [@var{arguments} @dots{}]
+@end example
+
+Runs @var{command} with @var{arguments} ignoring any shell function
+named @var{command}.
+Only shell builtin commands or commands found by searching the
+@env{PATH} are executed.
+If there is a shell function named @code{ls}, running @samp{command ls}
+within the function will execute the external command @code{ls}
+instead of calling the function recursively.
+The @option{-p} option means to use a default value for @env{PATH}
+that is guaranteed to find all of the standard utilities.
+The return status in this case is 127 if @var{command} cannot be
+found or an error occurred, and the exit status of @var{command}
+otherwise.
+
+If either the @option{-V} or @option{-v} option is supplied, a
+description of @var{command} is printed. The @option{-v} option
+causes a single word indicating the command or file name used to
+invoke @var{command} to be displayed; the @option{-V} option produces
+a more verbose description. In this case, the return status is
+zero if @var{command} is found, and non-zero if not.
+
+@item declare
+@btindex declare
+@example
+declare [-aAfFgilnrtux] [-p] [@var{name}[=@var{value}] @dots{}]
+@end example
+
+Declare variables and give them attributes. If no @var{name}s
+are given, then display the values of variables instead.
+
+The @option{-p} option will display the attributes and values of each
+@var{name}.
+When @option{-p} is used with @var{name} arguments, additional options,
+other than @option{-f} and @option{-F}, are ignored.
+
+When @option{-p} is supplied without @var{name} arguments, @code{declare}
+will display the attributes and values of all variables having the
+attributes specified by the additional options.
+If no other options are supplied with @option{-p}, @code{declare} will
+display the attributes and values of all shell variables. The @option{-f}
+option will restrict the display to shell functions.
+
+The @option{-F} option inhibits the display of function definitions;
+only the function name and attributes are printed.
+If the @code{extdebug} shell option is enabled using @code{shopt}
+(@pxref{The Shopt Builtin}), the source file name and line number where
+the function is defined are displayed as well.
+@option{-F} implies @option{-f}.
+
+The @option{-g} option forces variables to be created or modified at
+the global scope, even when @code{declare} is executed in a shell function.
+It is ignored in all other cases.
+
+The following options can be used to restrict output to variables with
+the specified attributes or to give variables attributes:
+
+@table @code
+@item -a
+Each @var{name} is an indexed array variable (@pxref{Arrays}).
+
+@item -A
+Each @var{name} is an associative array variable (@pxref{Arrays}).
+
+@item -f
+Use function names only.
+
+@item -i
+The variable is to be treated as
+an integer; arithmetic evaluation (@pxref{Shell Arithmetic}) is
+performed when the variable is assigned a value.
+
+@item -l
+When the variable is assigned a value, all upper-case characters are
+converted to lower-case.
+The upper-case attribute is disabled.
+
+@item -n
+Give each @var{name} the @var{nameref} attribute, making
+it a name reference to another variable.
+That other variable is defined by the value of @var{name}.
+All references, assignments, and attribute modifications
+to @var{name}, except for changing the
+@option{-n} attribute itself, are performed on the variable referenced by
+@var{name}'s value.
+The nameref attribute cannot be applied to array variables.
+
+@item -r
+Make @var{name}s readonly. These names cannot then be assigned values
+by subsequent assignment statements or unset.
+
+@item -t
+Give each @var{name} the @code{trace} attribute.
+Traced functions inherit the @code{DEBUG} and @code{RETURN} traps from
+the calling shell.
+The trace attribute has no special meaning for variables.
+
+@item -u
+When the variable is assigned a value, all lower-case characters are
+converted to upper-case.
+The lower-case attribute is disabled.
+
+@item -x
+Mark each @var{name} for export to subsequent commands via
+the environment.
+@end table
+
+Using @samp{+} instead of @samp{-} turns off the attribute instead,
+with the exceptions that @samp{+a}
+may not be used to destroy an array variable and @samp{+r} will not
+remove the readonly attribute.
+When used in a function, @code{declare} makes each @var{name} local,
+as with the @code{local} command, unless the @option{-g} option is used.
+If a variable name is followed by =@var{value}, the value of the variable
+is set to @var{value}.
+
+When using @option{-a} or @option{-A} and the compound assignment syntax to
+create array variables, additional attributes do not take effect until
+subsequent assignments.
+
+The return status is zero unless an invalid option is encountered,
+an attempt is made to define a function using @samp{-f foo=bar},
+an attempt is made to assign a value to a readonly variable,
+an attempt is made to assign a value to an array variable without
+using the compound assignment syntax (@pxref{Arrays}),
+one of the @var{names} is not a valid shell variable name,
+an attempt is made to turn off readonly status for a readonly variable,
+an attempt is made to turn off array status for an array variable,
+or an attempt is made to display a non-existent function with @option{-f}.
+
+@item echo
+@btindex echo
+@example
+echo [-neE] [@var{arg} @dots{}]
+@end example
+
+Output the @var{arg}s, separated by spaces, terminated with a
+newline.
+The return status is 0 unless a write error occurs.
+If @option{-n} is specified, the trailing newline is suppressed.
+If the @option{-e} option is given, interpretation of the following
+backslash-escaped characters is enabled.
+The @option{-E} option disables the interpretation of these escape characters,
+even on systems where they are interpreted by default.
+The @code{xpg_echo} shell option may be used to
+dynamically determine whether or not @code{echo} expands these
+escape characters by default.
+@code{echo} does not interpret @option{--} to mean the end of options.
+
+@code{echo} interprets the following escape sequences:
+@table @code
+@item \a
+alert (bell)
+@item \b
+backspace
+@item \c
+suppress further output
+@item \e
+@itemx \E
+escape
+@item \f
+form feed
+@item \n
+new line
+@item \r
+carriage return
+@item \t
+horizontal tab
+@item \v
+vertical tab
+@item \\
+backslash
+@item \0@var{nnn}
+the eight-bit character whose value is the octal value @var{nnn}
+(zero to three octal digits)
+@item \x@var{HH}
+the eight-bit character whose value is the hexadecimal value @var{HH}
+(one or two hex digits)
+@item \u@var{HHHH}
+the Unicode (ISO/IEC 10646) character whose value is the hexadecimal value
+@var{HHHH} (one to four hex digits)
+@item \U@var{HHHHHHHH}
+the Unicode (ISO/IEC 10646) character whose value is the hexadecimal value
+@var{HHHHHHHH} (one to eight hex digits)
+@end table
+
+@item enable
+@btindex enable
+@example
+enable [-a] [-dnps] [-f @var{filename}] [@var{name} @dots{}]
+@end example
+
+Enable and disable builtin shell commands.
+Disabling a builtin allows a disk command which has the same name
+as a shell builtin to be executed without specifying a full pathname,
+even though the shell normally searches for builtins before disk commands.
+If @option{-n} is used, the @var{name}s become disabled. Otherwise
+@var{name}s are enabled. For example, to use the @code{test} binary
+found via @env{$PATH} instead of the shell builtin version, type
+@samp{enable -n test}.
+
+If the @option{-p} option is supplied, or no @var{name} arguments appear,
+a list of shell builtins is printed. With no other arguments, the list
+consists of all enabled shell builtins.
+The @option{-a} option means to list
+each builtin with an indication of whether or not it is enabled.
+
+The @option{-f} option means to load the new builtin command @var{name}
+from shared object @var{filename}, on systems that support dynamic loading.
+The @option{-d} option will delete a builtin loaded with @option{-f}.
+
+If there are no options, a list of the shell builtins is displayed.
+The @option{-s} option restricts @code{enable} to the @sc{posix} special
+builtins. If @option{-s} is used with @option{-f}, the new builtin becomes
+a special builtin (@pxref{Special Builtins}).
+
+The return status is zero unless a @var{name} is not a shell builtin
+or there is an error loading a new builtin from a shared object.
+
+@item help
+@btindex help
+@example
+help [-dms] [@var{pattern}]
+@end example
+
+Display helpful information about builtin commands.
+If @var{pattern} is specified, @code{help} gives detailed help
+on all commands matching @var{pattern}, otherwise a list of
+the builtins is printed.
+
+Options, if supplied, have the following meanings:
+
+@table @code
+@item -d
+Display a short description of each @var{pattern}
+@item -m
+Display the description of each @var{pattern} in a manpage-like format
+@item -s
+Display only a short usage synopsis for each @var{pattern}
+@end table
+
+The return status is zero unless no command matches @var{pattern}.
+
+@item let
+@btindex let
+@example
+let @var{expression} [@var{expression} @dots{}]
+@end example
+
+The @code{let} builtin allows arithmetic to be performed on shell
+variables. Each @var{expression} is evaluated according to the
+rules given below in @ref{Shell Arithmetic}. If the
+last @var{expression} evaluates to 0, @code{let} returns 1;
+otherwise 0 is returned.
+
+@item local
+@btindex local
+@example
+local [@var{option}] @var{name}[=@var{value}] @dots{}
+@end example
+
+For each argument, a local variable named @var{name} is created,
+and assigned @var{value}.
+The @var{option} can be any of the options accepted by @code{declare}.
+@code{local} can only be used within a function; it makes the variable
+@var{name} have a visible scope restricted to that function and its
+children. The return status is zero unless @code{local} is used outside
+a function, an invalid @var{name} is supplied, or @var{name} is a
+readonly variable.
+
+@item logout
+@btindex logout
+@example
+logout [@var{n}]
+@end example
+
+Exit a login shell, returning a status of @var{n} to the shell's
+parent.
+
+@item mapfile
+@btindex mapfile
+@example
+mapfile [-d @var{delim}] [-n @var{count}] [-O @var{origin}] [-s @var{count}] [-t] [-u @var{fd}]
+ [-C @var{callback}] [-c @var{quantum}] [@var{array}]
+@end example
+
+Read lines from the standard input into the indexed array variable @var{array},
+or from file descriptor @var{fd}
+if the @option{-u} option is supplied.
+The variable @code{MAPFILE} is the default @var{array}.
+Options, if supplied, have the following meanings:
+
+@table @code
+
+@item -d
+The first character of @var{delim} is used to terminate each input line,
+rather than newline.
+@item -n
+Copy at most @var{count} lines. If @var{count} is 0, all lines are copied.
+@item -O
+Begin assigning to @var{array} at index @var{origin}.
+The default index is 0.
+@item -s
+Discard the first @var{count} lines read.
+@item -t
+Remove a trailing newline from each line read.
+@item -u
+Read lines from file descriptor @var{fd} instead of the standard input.
+@item -C
+Evaluate @var{callback} each time @var{quantum}P lines are read.
+The @option{-c} option specifies @var{quantum}.
+@item -c
+Specify the number of lines read between each call to @var{callback}.
+@end table
+
+If @option{-C} is specified without @option{-c},
+the default quantum is 5000.
+When @var{callback} is evaluated, it is supplied the index of the next
+array element to be assigned and the line to be assigned to that element
+as additional arguments.
+@var{callback} is evaluated after the line is read but before the
+array element is assigned.
+
+If not supplied with an explicit origin, @code{mapfile} will clear @var{array}
+before assigning to it.
+
+@code{mapfile} returns successfully unless an invalid option or option
+argument is supplied, @var{array} is invalid or unassignable, or @var{array}
+is not an indexed array.
+
+@item printf
+@btindex printf
+@example
+printf [-v @var{var}] @var{format} [@var{arguments}]
+@end example
+
+Write the formatted @var{arguments} to the standard output under the
+control of the @var{format}.
+The @option{-v} option causes the output to be assigned to the variable
+@var{var} rather than being printed to the standard output.
+
+The @var{format} is a character string which contains three types of objects:
+plain characters, which are simply copied to standard output, character
+escape sequences, which are converted and copied to the standard output, and
+format specifications, each of which causes printing of the next successive
+@var{argument}.
+In addition to the standard @code{printf(1)} formats, @code{printf}
+interprets the following extensions:
+
+@table @code
+@item %b
+Causes @code{printf} to expand backslash escape sequences in the
+corresponding @var{argument},
+except that @samp{\c} terminates output, backslashes in
+@samp{\'}, @samp{\"}, and @samp{\?} are not removed, and octal escapes
+beginning with @samp{\0} may contain up to four digits.
+@item %q
+Causes @code{printf} to output the
+corresponding @var{argument} in a format that can be reused as shell input.
+@item %(@var{datefmt})T
+Causes @code{printf} to output the date-time string resulting from using
+@var{datefmt} as a format string for @code{strftime}(3).
+The corresponding @var{argument} is an integer representing the number of
+seconds since the epoch.
+Two special argument values may be used: -1 represents the current
+time, and -2 represents the time the shell was invoked.
+If no argument is specified, conversion behaves as if -1 had been given.
+This is an exception to the usual @code{printf} behavior.
+@end table
+
+@noindent
+Arguments to non-string format specifiers are treated as C language constants,
+except that a leading plus or minus sign is allowed, and if the leading
+character is a single or double quote, the value is the ASCII value of
+the following character.
+
+The @var{format} is reused as necessary to consume all of the @var{arguments}.
+If the @var{format} requires more @var{arguments} than are supplied, the
+extra format specifications behave as if a zero value or null string, as
+appropriate, had been supplied. The return value is zero on success,
+non-zero on failure.
+
+@item read
+@btindex read
+@example
+read [-ers] [-a @var{aname}] [-d @var{delim}] [-i @var{text}] [-n @var{nchars}]
+ [-N @var{nchars}] [-p @var{prompt}] [-t @var{timeout}] [-u @var{fd}] [@var{name} @dots{}]
+@end example
+
+One line is read from the standard input, or from the file descriptor
+@var{fd} supplied as an argument to the @option{-u} option, and the first word
+is assigned to the first @var{name}, the second word to the second @var{name},
+and so on, with leftover words and their intervening separators assigned
+to the last @var{name}.
+If there are fewer words read from the input stream than names,
+the remaining names are assigned empty values.
+The characters in the value of the @env{IFS} variable
+are used to split the line into words using the same rules the shell
+uses for expansion (described above in @ref{Word Splitting}).
+The backslash character @samp{\} may be used to remove any special
+meaning for the next character read and for line continuation.
+If no names are supplied, the line read is assigned to the
+variable @env{REPLY}.
+The return code is zero, unless end-of-file is encountered, @code{read}
+times out (in which case the return code is greater than 128),
+a variable assignment error (such as assigning to a readonly variable) occurs,
+or an invalid file descriptor is supplied as the argument to @option{-u}.
+
+Options, if supplied, have the following meanings:
+
+@table @code
+@item -a @var{aname}
+The words are assigned to sequential indices of the array variable
+@var{aname}, starting at 0.
+All elements are removed from @var{aname} before the assignment.
+Other @var{name} arguments are ignored.
+
+@item -d @var{delim}
+The first character of @var{delim} is used to terminate the input line,
+rather than newline.
+
+@item -e
+Readline (@pxref{Command Line Editing}) is used to obtain the line.
+Readline uses the current (or default, if line editing was not previously
+active) editing settings.
+
+@item -i @var{text}
+If Readline is being used to read the line, @var{text} is placed into
+the editing buffer before editing begins.
+
+@item -n @var{nchars}
+@code{read} returns after reading @var{nchars} characters rather than
+waiting for a complete line of input, but honor a delimiter if fewer
+than @var{nchars} characters are read before the delimiter.
+
+@item -N @var{nchars}
+@code{read} returns after reading exactly @var{nchars} characters rather
+than waiting for a complete line of input, unless EOF is encountered or
+@code{read} times out.
+Delimiter characters encountered in the input are
+not treated specially and do not cause @code{read} to return until
+@var{nchars} characters are read.
+
+@item -p @var{prompt}
+Display @var{prompt}, without a trailing newline, before attempting
+to read any input.
+The prompt is displayed only if input is coming from a terminal.
+
+@item -r
+If this option is given, backslash does not act as an escape character.
+The backslash is considered to be part of the line.
+In particular, a backslash-newline pair may not be used as a line
+continuation.
+
+@item -s
+Silent mode. If input is coming from a terminal, characters are
+not echoed.
+
+@item -t @var{timeout}
+Cause @code{read} to time out and return failure if a complete line of
+input (or a specified number of characters)
+is not read within @var{timeout} seconds.
+@var{timeout} may be a decimal number with a fractional portion following
+the decimal point.
+This option is only effective if @code{read} is reading input from a
+terminal, pipe, or other special file; it has no effect when reading
+from regular files.
+If @code{read} times out, @code{read} saves any partial input read into
+the specified variable @var{name}.
+If @var{timeout} is 0, @code{read} returns immediately, without trying to
+read and data. The exit status is 0 if input is available on
+the specified file descriptor, non-zero otherwise.
+The exit status is greater than 128 if the timeout is exceeded.
+
+@item -u @var{fd}
+Read input from file descriptor @var{fd}.
+@end table
+
+@item readarray
+@btindex readarray
+@example
+readarray [-d @var{delim}] [-n @var{count}] [-O @var{origin}] [-s @var{count}] [-t] [-u @var{fd}]
+ [-C @var{callback}] [-c @var{quantum}] [@var{array}]
+@end example
+
+Read lines from the standard input into the indexed array variable @var{array},
+or from file descriptor @var{fd}
+if the @option{-u} option is supplied.
+
+A synonym for @code{mapfile}.
+
+@item source
+@btindex source
+@example
+source @var{filename}
+@end example
+
+A synonym for @code{.} (@pxref{Bourne Shell Builtins}).
+
+@item type
+@btindex type
+@example
+type [-afptP] [@var{name} @dots{}]
+@end example
+
+For each @var{name}, indicate how it would be interpreted if used as a
+command name.
+
+If the @option{-t} option is used, @code{type} prints a single word
+which is one of @samp{alias}, @samp{function}, @samp{builtin},
+@samp{file} or @samp{keyword},
+if @var{name} is an alias, shell function, shell builtin,
+disk file, or shell reserved word, respectively.
+If the @var{name} is not found, then nothing is printed, and
+@code{type} returns a failure status.
+
+If the @option{-p} option is used, @code{type} either returns the name
+of the disk file that would be executed, or nothing if @option{-t}
+would not return @samp{file}.
+
+The @option{-P} option forces a path search for each @var{name}, even if
+@option{-t} would not return @samp{file}.
+
+If a command is hashed, @option{-p} and @option{-P} print the hashed value,
+which is not necessarily the file that appears first in @code{$PATH}.
+
+If the @option{-a} option is used, @code{type} returns all of the places
+that contain an executable named @var{file}.
+This includes aliases and functions, if and only if the @option{-p} option
+is not also used.
+
+If the @option{-f} option is used, @code{type} does not attempt to find
+shell functions, as with the @code{command} builtin.
+
+The return status is zero if all of the @var{names} are found, non-zero
+if any are not found.
+
+@item typeset
+@btindex typeset
+@example
+typeset [-afFgrxilnrtux] [-p] [@var{name}[=@var{value}] @dots{}]
+@end example
+
+The @code{typeset} command is supplied for compatibility with the Korn
+shell.
+It is a synonym for the @code{declare} builtin command.
+
+@item ulimit
+@btindex ulimit
+@example
+ulimit [-HSabcdefiklmnpqrstuvxPT] [@var{limit}]
+@end example
+
+@code{ulimit} provides control over the resources available to processes
+started by the shell, on systems that allow such control. If an
+option is given, it is interpreted as follows:
+
+@table @code
+@item -S
+Change and report the soft limit associated with a resource.
+
+@item -H
+Change and report the hard limit associated with a resource.
+
+@item -a
+All current limits are reported.
+
+@item -b
+The maximum socket buffer size.
+
+@item -c
+The maximum size of core files created.
+
+@item -d
+The maximum size of a process's data segment.
+
+@item -e
+The maximum scheduling priority ("nice").
+
+@item -f
+The maximum size of files written by the shell and its children.
+
+@item -i
+The maximum number of pending signals.
+
+@item -k
+The maximum number of kqueues that may be allocated.
+
+@item -l
+The maximum size that may be locked into memory.
+
+@item -m
+The maximum resident set size (many systems do not honor this limit).
+
+@item -n
+The maximum number of open file descriptors (most systems do not
+allow this value to be set).
+
+@item -p
+The pipe buffer size.
+
+@item -q
+The maximum number of bytes in POSIX message queues.
+
+@item -r
+The maximum real-time scheduling priority.
+
+@item -s
+The maximum stack size.
+
+@item -t
+The maximum amount of cpu time in seconds.
+
+@item -u
+The maximum number of processes available to a single user.
+
+@item -v
+The maximum amount of virtual memory available to the shell, and, on
+some systems, to its children.
+
+@item -x
+The maximum number of file locks.
+
+@item -P
+The maximum number of pseudoterminals.
+
+@item -T
+The maximum number of threads.
+@end table
+
+If @var{limit} is given, and the @option{-a} option is not used,
+@var{limit} is the new value of the specified resource.
+The special @var{limit} values @code{hard}, @code{soft}, and
+@code{unlimited} stand for the current hard limit, the current soft limit,
+and no limit, respectively.
+A hard limit cannot be increased by a non-root user once it is set;
+a soft limit may be increased up to the value of the hard limit.
+Otherwise, the current value of the soft limit for the specified resource
+is printed, unless the @option{-H} option is supplied.
+When setting new limits, if neither @option{-H} nor @option{-S} is supplied,
+both the hard and soft limits are set.
+If no option is given, then @option{-f} is assumed. Values are in 1024-byte
+increments, except for @option{-t}, which is in seconds; @option{-p},
+which is in units of 512-byte blocks; and @option{-P}, @option{-T},
+@option{-b},
+@option{-k}, @option{-n} and @option{-u}, which are unscaled values.
+
+The return status is zero unless an invalid option or argument is supplied,
+or an error occurs while setting a new limit.
+
+@item unalias
+@btindex unalias
+@example
+unalias [-a] [@var{name} @dots{} ]
+@end example
+
+Remove each @var{name} from the list of aliases. If @option{-a} is
+supplied, all aliases are removed.
+Aliases are described in @ref{Aliases}.
+@end table
+
+@node Modifying Shell Behavior
+@section Modifying Shell Behavior
+
+@menu
+* The Set Builtin:: Change the values of shell attributes and
+ positional parameters.
+* The Shopt Builtin:: Modify shell optional behavior.
+@end menu
+
+@node The Set Builtin
+@subsection The Set Builtin
+
+This builtin is so complicated that it deserves its own section. @code{set}
+allows you to change the values of shell options and set the positional
+parameters, or to display the names and values of shell variables.
+
+@table @code
+@item set
+@btindex set
+@example
+set [--abefhkmnptuvxBCEHPT] [-o @var{option-name}] [@var{argument} @dots{}]
+set [+abefhkmnptuvxBCEHPT] [+o @var{option-name}] [@var{argument} @dots{}]
+@end example
+
+If no options or arguments are supplied, @code{set} displays the names
+and values of all shell variables and functions, sorted according to the
+current locale, in a format that may be reused as input
+for setting or resetting the currently-set variables.
+Read-only variables cannot be reset.
+In @sc{posix} mode, only shell variables are listed.
+
+When options are supplied, they set or unset shell attributes.
+Options, if specified, have the following meanings:
+
+@table @code
+@item -a
+Mark variables and function which are modified or created for export
+to the environment of subsequent commands.
+
+@item -b
+Cause the status of terminated background jobs to be reported
+immediately, rather than before printing the next primary prompt.
+
+@item -e
+Exit immediately if
+a pipeline (@pxref{Pipelines}), which may consist of a single simple command
+(@pxref{Simple Commands}),
+a list (@pxref{Lists}),
+or a compound command (@pxref{Compound Commands})
+returns a non-zero status.
+The shell does not exit if the command that fails is part of the
+command list immediately following a @code{while} or @code{until} keyword,
+part of the test in an @code{if} statement,
+part of any command executed in a @code{&&} or @code{||} list except
+the command following the final @code{&&} or @code{||},
+any command in a pipeline but the last,
+or if the command's return status is being inverted with @code{!}.
+If a compound command other than a subshell
+returns a non-zero status because a command failed
+while @option{-e} was being ignored, the shell does not exit.
+A trap on @code{ERR}, if set, is executed before the shell exits.
+
+This option applies to the shell environment and each subshell environment
+separately (@pxref{Command Execution Environment}), and may cause
+subshells to exit before executing all the commands in the subshell.
+
+If a compound command or shell function executes in a context where
+@option{-e} is being ignored,
+none of the commands executed within the compound command or function body
+will be affected by the @option{-e} setting, even if @option{-e} is set
+and a command returns a failure status.
+If a compound command or shell function sets @option{-e} while executing in
+a context where @option{-e} is ignored, that setting will not have any
+effect until the compound command or the command containing the function
+call completes.
+
+@item -f
+Disable filename expansion (globbing).
+
+@item -h
+Locate and remember (hash) commands as they are looked up for execution.
+This option is enabled by default.
+
+@item -k
+All arguments in the form of assignment statements are placed
+in the environment for a command, not just those that precede
+the command name.
+
+@item -m
+Job control is enabled (@pxref{Job Control}).
+All processes run in a separate process group.
+When a background job completes, the shell prints a line
+containing its exit status.
+
+@item -n
+Read commands but do not execute them.
+This may be used to check a script for syntax errors.
+This option is ignored by interactive shells.
+
+@item -o @var{option-name}
+
+Set the option corresponding to @var{option-name}:
+
+@table @code
+@item allexport
+Same as @code{-a}.
+
+@item braceexpand
+Same as @code{-B}.
+
+@item emacs
+Use an @code{emacs}-style line editing interface (@pxref{Command Line Editing}).
+This also affects the editing interface used for @code{read -e}.
+
+@item errexit
+Same as @code{-e}.
+
+@item errtrace
+Same as @code{-E}.
+
+@item functrace
+Same as @code{-T}.
+
+@item hashall
+Same as @code{-h}.
+
+@item histexpand
+Same as @code{-H}.
+
+@item history
+Enable command history, as described in @ref{Bash History Facilities}.
+This option is on by default in interactive shells.
+
+@item ignoreeof
+An interactive shell will not exit upon reading EOF.
+
+@item keyword
+Same as @code{-k}.
+
+@item monitor
+Same as @code{-m}.
+
+@item noclobber
+Same as @code{-C}.
+
+@item noexec
+Same as @code{-n}.
+
+@item noglob
+Same as @code{-f}.
+
+@item nolog
+Currently ignored.
+
+@item notify
+Same as @code{-b}.
+
+@item nounset
+Same as @code{-u}.
+
+@item onecmd
+Same as @code{-t}.
+
+@item physical
+Same as @code{-P}.
+
+@item pipefail
+If set, the return value of a pipeline is the value of the last
+(rightmost) command to exit with a non-zero status, or zero if all
+commands in the pipeline exit successfully.
+This option is disabled by default.
+
+@item posix
+Change the behavior of Bash where the default operation differs
+from the @sc{posix} standard to match the standard
+(@pxref{Bash POSIX Mode}).
+This is intended to make Bash behave as a strict superset of that
+standard.
+
+@item privileged
+Same as @code{-p}.
+
+@item verbose
+Same as @code{-v}.
+
+@item vi
+Use a @code{vi}-style line editing interface.
+This also affects the editing interface used for @code{read -e}.
+
+@item xtrace
+Same as @code{-x}.
+@end table
+
+@item -p
+Turn on privileged mode.
+In this mode, the @env{$BASH_ENV} and @env{$ENV} files are not
+processed, shell functions are not inherited from the environment,
+and the @env{SHELLOPTS}, @env{BASHOPTS}, @env{CDPATH} and @env{GLOBIGNORE}
+variables, if they appear in the environment, are ignored.
+If the shell is started with the effective user (group) id not equal to the
+real user (group) id, and the @option{-p} option is not supplied, these actions
+are taken and the effective user id is set to the real user id.
+If the @option{-p} option is supplied at startup, the effective user id is
+not reset.
+Turning this option off causes the effective user
+and group ids to be set to the real user and group ids.
+
+@item -t
+Exit after reading and executing one command.
+
+@item -u
+Treat unset variables and parameters other than the special parameters
+@samp{@@} or @samp{*} as an error when performing parameter expansion.
+An error message will be written to the standard error, and a non-interactive
+shell will exit.
+
+@item -v
+Print shell input lines as they are read.
+
+@item -x
+Print a trace of simple commands, @code{for} commands, @code{case}
+commands, @code{select} commands, and arithmetic @code{for} commands
+and their arguments or associated word lists after they are
+expanded and before they are executed. The value of the @env{PS4}
+variable is expanded and the resultant value is printed before
+the command and its expanded arguments.
+
+@item -B
+The shell will perform brace expansion (@pxref{Brace Expansion}).
+This option is on by default.
+
+@item -C
+Prevent output redirection using @samp{>}, @samp{>&}, and @samp{<>}
+from overwriting existing files.
+
+@item -E
+If set, any trap on @code{ERR} is inherited by shell functions, command
+substitutions, and commands executed in a subshell environment.
+The @code{ERR} trap is normally not inherited in such cases.
+
+@item -H
+Enable @samp{!} style history substitution (@pxref{History Interaction}).
+This option is on by default for interactive shells.
+
+@item -P
+If set, do not resolve symbolic links when performing commands such as
+@code{cd} which change the current directory. The physical directory
+is used instead. By default, Bash follows
+the logical chain of directories when performing commands
+which change the current directory.
+
+For example, if @file{/usr/sys} is a symbolic link to @file{/usr/local/sys}
+then:
+@example
+$ cd /usr/sys; echo $PWD
+/usr/sys
+$ cd ..; pwd
+/usr
+@end example
+
+@noindent
+If @code{set -P} is on, then:
+@example
+$ cd /usr/sys; echo $PWD
+/usr/local/sys
+$ cd ..; pwd
+/usr/local
+@end example
+
+@item -T
+If set, any trap on @code{DEBUG} and @code{RETURN} are inherited by
+shell functions, command substitutions, and commands executed
+in a subshell environment.
+The @code{DEBUG} and @code{RETURN} traps are normally not inherited
+in such cases.
+
+@item --
+If no arguments follow this option, then the positional parameters are
+unset. Otherwise, the positional parameters are set to the
+@var{arguments}, even if some of them begin with a @samp{-}.
+
+@item -
+Signal the end of options, cause all remaining @var{arguments}
+to be assigned to the positional parameters. The @option{-x}
+and @option{-v} options are turned off.
+If there are no arguments, the positional parameters remain unchanged.
+@end table
+
+Using @samp{+} rather than @samp{-} causes these options to be
+turned off. The options can also be used upon invocation of the
+shell. The current set of options may be found in @code{$-}.
+
+The remaining N @var{arguments} are positional parameters and are
+assigned, in order, to @code{$1}, @code{$2}, @dots{} @code{$N}.
+The special parameter @code{#} is set to N.
+
+The return status is always zero unless an invalid option is supplied.
+@end table
+
+@node The Shopt Builtin
+@subsection The Shopt Builtin
+
+This builtin allows you to change additional shell optional behavior.
+
+@table @code
+
+@item shopt
+@btindex shopt
+@example
+shopt [-pqsu] [-o] [@var{optname} @dots{}]
+@end example
+
+Toggle the values of settings controlling optional shell behavior.
+The settings can be either those listed below, or, if the
+@option{-o} option is used, those available with the @option{-o}
+option to the @code{set} builtin command (@pxref{The Set Builtin}).
+With no options, or with the @option{-p} option, a list of all settable
+options is displayed, with an indication of whether or not each is set.
+The @option{-p} option causes output to be displayed in a form that
+may be reused as input.
+Other options have the following meanings:
+
+@table @code
+@item -s
+Enable (set) each @var{optname}.
+
+@item -u
+Disable (unset) each @var{optname}.
+
+@item -q
+Suppresses normal output; the return status
+indicates whether the @var{optname} is set or unset.
+If multiple @var{optname} arguments are given with @option{-q},
+the return status is zero if all @var{optnames} are enabled;
+non-zero otherwise.
+
+@item -o
+Restricts the values of
+@var{optname} to be those defined for the @option{-o} option to the
+@code{set} builtin (@pxref{The Set Builtin}).
+@end table
+
+If either @option{-s} or @option{-u}
+is used with no @var{optname} arguments, @code{shopt} shows only
+those options which are set or unset, respectively.
+
+Unless otherwise noted, the @code{shopt} options are disabled (off)
+by default.
+
+The return status when listing options is zero if all @var{optnames}
+are enabled, non-zero otherwise. When setting or unsetting options,
+the return status is zero unless an @var{optname} is not a valid shell
+option.
+
+The list of @code{shopt} options is:
+@table @code
+
+@item autocd
+If set, a command name that is the name of a directory is executed as if
+it were the argument to the @code{cd} command.
+This option is only used by interactive shells.
+
+@item cdable_vars
+If this is set, an argument to the @code{cd} builtin command that
+is not a directory is assumed to be the name of a variable whose
+value is the directory to change to.
+
+@item cdspell
+If set, minor errors in the spelling of a directory component in a
+@code{cd} command will be corrected.
+The errors checked for are transposed characters,
+a missing character, and a character too many.
+If a correction is found, the corrected path is printed,
+and the command proceeds.
+This option is only used by interactive shells.
+
+@item checkhash
+If this is set, Bash checks that a command found in the hash
+table exists before trying to execute it. If a hashed command no
+longer exists, a normal path search is performed.
+
+@item checkjobs
+If set, Bash lists the status of any stopped and running jobs before
+exiting an interactive shell. If any jobs are running, this causes
+the exit to be deferred until a second exit is attempted without an
+intervening command (@pxref{Job Control}).
+The shell always postpones exiting if any jobs are stopped.
+
+@item checkwinsize
+If set, Bash checks the window size after each command
+ and, if necessary, updates the values of
+@env{LINES} and @env{COLUMNS}.
+
+@item cmdhist
+If set, Bash
+attempts to save all lines of a multiple-line
+command in the same history entry. This allows
+easy re-editing of multi-line commands.
+
+@item compat31
+If set, Bash
+changes its behavior to that of version 3.1 with respect to quoted
+arguments to the conditional command's @samp{=~} operator
+and with respect to locale-specific
+string comparison when using the @code{[[}
+conditional command's @samp{<} and @samp{>} operators.
+Bash versions prior to bash-4.1 use ASCII collation and strcmp(3);
+bash-4.1 and later use the current locale's collation sequence and strcoll(3).
+
+@item compat32
+If set, Bash
+changes its behavior to that of version 3.2 with respect to locale-specific
+string comparison when using the @code{[[}
+conditional command's @samp{<} and @samp{>} operators (see previous item).
+
+@item compat40
+If set, Bash
+changes its behavior to that of version 4.0 with respect to locale-specific
+string comparison when using the @code{[[}
+conditional command's @samp{<} and @samp{>} operators (see description
+of @code{compat31})
+and the effect of interrupting a command list.
+Bash versions 4.0 and later interrupt the list as if the shell received the
+interrupt; previous versions continue with the next command in the list.
+
+@item compat41
+If set, Bash, when in @sc{posix} mode, treats a single quote in a double-quoted
+parameter expansion as a special character. The single quotes must match
+(an even number) and the characters between the single quotes are considered
+quoted. This is the behavior of @sc{posix} mode through version 4.1.
+The default Bash behavior remains as in previous versions.
+
+@item compat42
+If set, Bash
+does not process the replacement string in the pattern substitution word
+expansion using quote removal.
+
+@item complete_fullquote
+If set, Bash
+quotes all shell metacharacters in filenames and directory names when
+performing completion.
+If not set, Bash
+removes metacharacters such as the dollar sign from the set of
+characters that will be quoted in completed filenames
+when these metacharacters appear in shell variable references in words to be
+completed.
+This means that dollar signs in variable names that expand to directories
+will not be quoted;
+however, any dollar signs appearing in filenames will not be quoted, either.
+This is active only when bash is using backslashes to quote completed
+filenames.
+This variable is set by default, which is the default Bash behavior in
+versions through 4.2.
+
+@item direxpand
+If set, Bash
+replaces directory names with the results of word expansion when performing
+filename completion. This changes the contents of the readline editing
+buffer.
+If not set, Bash attempts to preserve what the user typed.
+
+@item dirspell
+If set, Bash
+attempts spelling correction on directory names during word completion
+if the directory name initially supplied does not exist.
+
+@item dotglob
+If set, Bash includes filenames beginning with a `.' in
+the results of filename expansion.
+
+@item execfail
+If this is set, a non-interactive shell will not exit if
+it cannot execute the file specified as an argument to the @code{exec}
+builtin command. An interactive shell does not exit if @code{exec}
+fails.
+
+@item expand_aliases
+If set, aliases are expanded as described below under Aliases,
+@ref{Aliases}.
+This option is enabled by default for interactive shells.
+
+@item extdebug
+If set, behavior intended for use by debuggers is enabled:
+
+@enumerate
+@item
+The @option{-F} option to the @code{declare} builtin (@pxref{Bash Builtins})
+displays the source file name and line number corresponding to each function
+name supplied as an argument.
+
+@item
+If the command run by the @code{DEBUG} trap returns a non-zero value, the
+next command is skipped and not executed.
+
+@item
+If the command run by the @code{DEBUG} trap returns a value of 2, and the
+shell is executing in a subroutine (a shell function or a shell script
+executed by the @code{.} or @code{source} builtins), the shell simulates
+a call to @code{return}.
+
+@item
+@code{BASH_ARGC} and @code{BASH_ARGV} are updated as described in their
+descriptions (@pxref{Bash Variables}).
+
+@item
+Function tracing is enabled: command substitution, shell functions, and
+subshells invoked with @code{( @var{command} )} inherit the
+@code{DEBUG} and @code{RETURN} traps.
+
+@item
+Error tracing is enabled: command substitution, shell functions, and
+subshells invoked with @code{( @var{command} )} inherit the
+@code{ERR} trap.
+@end enumerate
+
+@item extglob
+If set, the extended pattern matching features described above
+(@pxref{Pattern Matching}) are enabled.
+
+@item extquote
+If set, @code{$'@var{string}'} and @code{$"@var{string}"} quoting is
+performed within @code{$@{@var{parameter}@}} expansions
+enclosed in double quotes. This option is enabled by default.
+
+@item failglob
+If set, patterns which fail to match filenames during filename expansion
+result in an expansion error.
+
+@item force_fignore
+If set, the suffixes specified by the @env{FIGNORE} shell variable
+cause words to be ignored when performing word completion even if
+the ignored words are the only possible completions.
+@xref{Bash Variables}, for a description of @env{FIGNORE}.
+This option is enabled by default.
+
+@item globasciiranges
+If set, range expressions used in pattern matching bracket expressions
+(@pxref{Pattern Matching})
+behave as if in the traditional C locale when performing
+comparisons. That is, the current locale's collating sequence
+is not taken into account, so
+@samp{b} will not collate between @samp{A} and @samp{B},
+and upper-case and lower-case ASCII characters will collate together.
+
+@item globstar
+If set, the pattern @samp{**} used in a filename expansion context will
+match all files and zero or more directories and subdirectories.
+If the pattern is followed by a @samp{/}, only directories and
+subdirectories match.
+
+@item gnu_errfmt
+If set, shell error messages are written in the standard @sc{gnu} error
+message format.
+
+@item histappend
+If set, the history list is appended to the file named by the value
+of the @env{HISTFILE}
+variable when the shell exits, rather than overwriting the file.
+
+@item histreedit
+If set, and Readline
+is being used, a user is given the opportunity to re-edit a
+failed history substitution.
+
+@item histverify
+If set, and Readline
+is being used, the results of history substitution are not immediately
+passed to the shell parser. Instead, the resulting line is loaded into
+the Readline editing buffer, allowing further modification.
+
+@item hostcomplete
+If set, and Readline is being used, Bash will attempt to perform
+hostname completion when a word containing a @samp{@@} is being
+completed (@pxref{Commands For Completion}). This option is enabled
+by default.
+
+@item huponexit
+If set, Bash will send @code{SIGHUP} to all jobs when an interactive
+login shell exits (@pxref{Signals}).
+
+@item interactive_comments
+Allow a word beginning with @samp{#}
+to cause that word and all remaining characters on that
+line to be ignored in an interactive shell.
+This option is enabled by default.
+
+@item lastpipe
+If set, and job control is not active, the shell runs the last command of
+a pipeline not executed in the background in the current shell environment.
+
+@item lithist
+If enabled, and the @code{cmdhist}
+option is enabled, multi-line commands are saved to the history with
+embedded newlines rather than using semicolon separators where possible.
+
+@item login_shell
+The shell sets this option if it is started as a login shell
+(@pxref{Invoking Bash}).
+The value may not be changed.
+
+@item mailwarn
+If set, and a file that Bash is checking for mail has been
+accessed since the last time it was checked, the message
+@code{"The mail in @var{mailfile} has been read"} is displayed.
+
+@item no_empty_cmd_completion
+If set, and Readline is being used, Bash will not attempt to search
+the @env{PATH} for possible completions when completion is attempted
+on an empty line.
+
+@item nocaseglob
+If set, Bash matches filenames in a case-insensitive fashion when
+performing filename expansion.
+
+@item nocasematch
+If set, Bash matches patterns in a case-insensitive fashion when
+performing matching while executing @code{case} or @code{[[}
+conditional commands,
+when performing pattern substitution word expansions,
+or when filtering possible completions as part of programmable completion.
+
+@item nullglob
+If set, Bash allows filename patterns which match no
+files to expand to a null string, rather than themselves.
+
+@item progcomp
+If set, the programmable completion facilities
+(@pxref{Programmable Completion}) are enabled.
+This option is enabled by default.
+
+@item promptvars
+If set, prompt strings undergo
+parameter expansion, command substitution, arithmetic
+expansion, and quote removal after being expanded
+as described below (@pxref{Controlling the Prompt}).
+This option is enabled by default.
+
+@item restricted_shell
+The shell sets this option if it is started in restricted mode
+(@pxref{The Restricted Shell}).
+The value may not be changed.
+This is not reset when the startup files are executed, allowing
+the startup files to discover whether or not a shell is restricted.
+
+@item shift_verbose
+If this is set, the @code{shift}
+builtin prints an error message when the shift count exceeds the
+number of positional parameters.
+
+@item sourcepath
+If set, the @code{source} builtin uses the value of @env{PATH}
+to find the directory containing the file supplied as an argument.
+This option is enabled by default.
+
+@item xpg_echo
+If set, the @code{echo} builtin expands backslash-escape sequences
+by default.
+
+@end table
+
+@noindent
+The return status when listing options is zero if all @var{optnames}
+are enabled, non-zero otherwise.
+When setting or unsetting options, the return status is zero unless an
+@var{optname} is not a valid shell option.
+@end table
+
+@node Special Builtins
+@section Special Builtins
+@cindex special builtin
+
+For historical reasons, the @sc{posix} standard has classified
+several builtin commands as @emph{special}.
+When Bash is executing in @sc{posix} mode, the special builtins
+differ from other builtin commands in three respects:
+
+@enumerate
+@item
+Special builtins are found before shell functions during command lookup.
+
+@item
+If a special builtin returns an error status, a non-interactive shell exits.
+
+@item
+Assignment statements preceding the command stay in effect in the shell
+environment after the command completes.
+@end enumerate
+
+When Bash is not executing in @sc{posix} mode, these builtins behave no
+differently than the rest of the Bash builtin commands.
+The Bash @sc{posix} mode is described in @ref{Bash POSIX Mode}.
+
+These are the @sc{posix} special builtins:
+@example
+@w{break : . continue eval exec exit export readonly return set}
+@w{shift trap unset}
+@end example
+
+@node Shell Variables
+@chapter Shell Variables
+
+@menu
+* Bourne Shell Variables:: Variables which Bash uses in the same way
+ as the Bourne Shell.
+* Bash Variables:: List of variables that exist in Bash.
+@end menu
+
+This chapter describes the shell variables that Bash uses.
+Bash automatically assigns default values to a number of variables.
+
+@node Bourne Shell Variables
+@section Bourne Shell Variables
+
+Bash uses certain shell variables in the same way as the Bourne shell.
+In some cases, Bash assigns a default value to the variable.
+
+@vtable @code
+
+@item CDPATH
+A colon-separated list of directories used as a search path for
+the @code{cd} builtin command.
+
+@item HOME
+The current user's home directory; the default for the @code{cd} builtin
+command.
+The value of this variable is also used by tilde expansion
+(@pxref{Tilde Expansion}).
+
+@item IFS
+A list of characters that separate fields; used when the shell splits
+words as part of expansion.
+
+@item MAIL
+If this parameter is set to a filename or directory name
+and the @env{MAILPATH} variable
+is not set, Bash informs the user of the arrival of mail in
+the specified file or Maildir-format directory.
+
+@item MAILPATH
+A colon-separated list of filenames which the shell periodically checks
+for new mail.
+Each list entry can specify the message that is printed when new mail
+arrives in the mail file by separating the filename from the message with
+a @samp{?}.
+When used in the text of the message, @code{$_} expands to the name of
+the current mail file.
+
+@item OPTARG
+The value of the last option argument processed by the @code{getopts} builtin.
+
+@item OPTIND
+The index of the last option argument processed by the @code{getopts} builtin.
+
+@item PATH
+A colon-separated list of directories in which the shell looks for
+commands.
+A zero-length (null) directory name in the value of @code{PATH} indicates the
+current directory.
+A null directory name may appear as two adjacent colons, or as an initial
+or trailing colon.
+
+
+@item PS1
+The primary prompt string. The default value is @samp{\s-\v\$ }.
+@xref{Controlling the Prompt}, for the complete list of escape
+sequences that are expanded before @env{PS1} is displayed.
+
+@item PS2
+The secondary prompt string. The default value is @samp{> }.
+
+@end vtable
+
+@node Bash Variables
+@section Bash Variables
+
+These variables are set or used by Bash, but other shells
+do not normally treat them specially.
+
+A few variables used by Bash are described in different chapters:
+variables for controlling the job control facilities
+(@pxref{Job Control Variables}).
+
+@vtable @code
+
+@item BASH
+The full pathname used to execute the current instance of Bash.
+
+@item BASHOPTS
+A colon-separated list of enabled shell options. Each word in
+the list is a valid argument for the @option{-s} option to the
+@code{shopt} builtin command (@pxref{The Shopt Builtin}).
+The options appearing in @env{BASHOPTS} are those reported
+as @samp{on} by @samp{shopt}.
+If this variable is in the environment when Bash
+starts up, each shell option in the list will be enabled before
+reading any startup files. This variable is readonly.
+
+@item BASHPID
+Expands to the process ID of the current Bash process.
+This differs from @code{$$} under certain circumstances, such as subshells
+that do not require Bash to be re-initialized.
+
+@item BASH_ALIASES
+An associative array variable whose members correspond to the internal
+list of aliases as maintained by the @code{alias} builtin.
+(@pxref{Bourne Shell Builtins}).
+Elements added to this array appear in the alias list; unsetting array
+elements cause aliases to be removed from the alias list.
+
+@item BASH_ARGC
+An array variable whose values are the number of parameters in each
+frame of the current bash execution call stack. The number of
+parameters to the current subroutine (shell function or script executed
+with @code{.} or @code{source}) is at the top of the stack. When a
+subroutine is executed, the number of parameters passed is pushed onto
+@code{BASH_ARGC}.
+The shell sets @code{BASH_ARGC} only when in extended debugging mode
+(see @ref{The Shopt Builtin}
+for a description of the @code{extdebug} option to the @code{shopt}
+builtin).
+
+@item BASH_ARGV
+An array variable containing all of the parameters in the current bash
+execution call stack. The final parameter of the last subroutine call
+is at the top of the stack; the first parameter of the initial call is
+at the bottom. When a subroutine is executed, the parameters supplied
+are pushed onto @code{BASH_ARGV}.
+The shell sets @code{BASH_ARGV} only when in extended debugging mode
+(see @ref{The Shopt Builtin}
+for a description of the @code{extdebug} option to the @code{shopt}
+builtin).
+
+@item BASH_CMDS
+An associative array variable whose members correspond to the internal
+hash table of commands as maintained by the @code{hash} builtin
+(@pxref{Bourne Shell Builtins}).
+Elements added to this array appear in the hash table; unsetting array
+elements cause commands to be removed from the hash table.
+
+@item BASH_COMMAND
+The command currently being executed or about to be executed, unless the
+shell is executing a command as the result of a trap,
+in which case it is the command executing at the time of the trap.
+
+@item BASH_COMPAT
+The value is used to set the shell's compatibility level.
+@xref{The Shopt Builtin}, for a description of the various compatibility
+levels and their effects.
+The value may be a decimal number (e.g., 4.2) or an integer (e.g., 42)
+corresponding to the desired compatibility level.
+If @code{BASH_COMPAT} is unset or set to the empty string, the compatibility
+level is set to the default for the current version.
+If @code{BASH_COMPAT} is set to a value that is not one of the valid
+compatibility levels, the shell prints an error message and sets the
+compatibility level to the default for the current version.
+The valid compatibility levels correspond to the compatibility options
+accepted by the @code{shopt} builtin described above (for example,
+@var{compat42} means that 4.2 and 42 are valid values).
+The current version is also a valid value.
+
+@item BASH_ENV
+If this variable is set when Bash is invoked to execute a shell
+script, its value is expanded and used as the name of a startup file
+to read before executing the script. @xref{Bash Startup Files}.
+
+@item BASH_EXECUTION_STRING
+The command argument to the @option{-c} invocation option.
+
+@item BASH_LINENO
+An array variable whose members are the line numbers in source files
+where each corresponding member of @var{FUNCNAME} was invoked.
+@code{$@{BASH_LINENO[$i]@}} is the line number in the source file
+(@code{$@{BASH_SOURCE[$i+1]@}}) where
+@code{$@{FUNCNAME[$i]@}} was called (or @code{$@{BASH_LINENO[$i-1]@}} if
+referenced within another shell function).
+Use @code{LINENO} to obtain the current line number.
+
+@item BASH_REMATCH
+An array variable whose members are assigned by the @samp{=~} binary
+operator to the @code{[[} conditional command
+(@pxref{Conditional Constructs}).
+The element with index 0 is the portion of the string
+matching the entire regular expression.
+The element with index @var{n} is the portion of the
+string matching the @var{n}th parenthesized subexpression.
+This variable is read-only.
+
+@item BASH_SOURCE
+An array variable whose members are the source filenames where the
+corresponding shell function names in the @code{FUNCNAME} array
+variable are defined.
+The shell function @code{$@{FUNCNAME[$i]@}} is defined in the file
+@code{$@{BASH_SOURCE[$i]@}} and called from @code{$@{BASH_SOURCE[$i+1]@}}
+
+@item BASH_SUBSHELL
+Incremented by one within each subshell or subshell environment when
+the shell begins executing in that environment.
+The initial value is 0.
+
+@item BASH_VERSINFO
+A readonly array variable (@pxref{Arrays})
+whose members hold version information for this instance of Bash.
+The values assigned to the array members are as follows:
+
+@table @code
+
+@item BASH_VERSINFO[0]
+The major version number (the @var{release}).
+
+@item BASH_VERSINFO[1]
+The minor version number (the @var{version}).
+
+@item BASH_VERSINFO[2]
+The patch level.
+
+@item BASH_VERSINFO[3]
+The build version.
+
+@item BASH_VERSINFO[4]
+The release status (e.g., @var{beta1}).
+
+@item BASH_VERSINFO[5]
+The value of @env{MACHTYPE}.
+@end table
+
+@item BASH_VERSION
+The version number of the current instance of Bash.
+
+@item BASH_XTRACEFD
+If set to an integer corresponding to a valid file descriptor, Bash
+will write the trace output generated when @samp{set -x}
+is enabled to that file descriptor.
+This allows tracing output to be separated from diagnostic and error
+messages.
+The file descriptor is closed when @code{BASH_XTRACEFD} is unset or assigned
+a new value.
+Unsetting @code{BASH_XTRACEFD} or assigning it the empty string causes the
+trace output to be sent to the standard error.
+Note that setting @code{BASH_XTRACEFD} to 2 (the standard error file
+descriptor) and then unsetting it will result in the standard error
+being closed.
+
+@item CHILD_MAX
+Set the number of exited child status values for the shell to remember.
+Bash will not allow this value to be decreased below a @sc{posix}-mandated
+minimum, and there is a maximum value (currently 8192) that this may
+not exceed.
+The minimum value is system-dependent.
+
+@item COLUMNS
+Used by the @code{select} command to determine the terminal width
+when printing selection lists.
+Automatically set if the @code{checkwinsize} option is enabled
+(@pxref{The Shopt Builtin}), or in an interactive shell upon receipt of a
+@code{SIGWINCH}.
+
+@item COMP_CWORD
+An index into @env{$@{COMP_WORDS@}} of the word containing the current
+cursor position.
+This variable is available only in shell functions invoked by the
+programmable completion facilities (@pxref{Programmable Completion}).
+
+@item COMP_LINE
+The current command line.
+This variable is available only in shell functions and external
+commands invoked by the
+programmable completion facilities (@pxref{Programmable Completion}).
+
+@item COMP_POINT
+The index of the current cursor position relative to the beginning of
+the current command.
+If the current cursor position is at the end of the current command,
+the value of this variable is equal to @code{$@{#COMP_LINE@}}.
+This variable is available only in shell functions and external
+commands invoked by the
+programmable completion facilities (@pxref{Programmable Completion}).
+
+@item COMP_TYPE
+Set to an integer value corresponding to the type of completion attempted
+that caused a completion function to be called:
+@var{TAB}, for normal completion,
+@samp{?}, for listing completions after successive tabs,
+@samp{!}, for listing alternatives on partial word completion,
+@samp{@@}, to list completions if the word is not unmodified,
+or
+@samp{%}, for menu completion.
+This variable is available only in shell functions and external
+commands invoked by the
+programmable completion facilities (@pxref{Programmable Completion}).
+
+@item COMP_KEY
+The key (or final key of a key sequence) used to invoke the current
+completion function.
+
+@item COMP_WORDBREAKS
+The set of characters that the Readline library treats as word
+separators when performing word completion.
+If @code{COMP_WORDBREAKS} is unset, it loses its special properties,
+even if it is subsequently reset.
+
+@item COMP_WORDS
+An array variable consisting of the individual
+words in the current command line.
+The line is split into words as Readline would split it, using
+@code{COMP_WORDBREAKS} as described above.
+This variable is available only in shell functions invoked by the
+programmable completion facilities (@pxref{Programmable Completion}).
+
+@item COMPREPLY
+An array variable from which Bash reads the possible completions
+generated by a shell function invoked by the programmable completion
+facility (@pxref{Programmable Completion}).
+Each array element contains one possible completion.
+
+@item COPROC
+An array variable created to hold the file descriptors
+for output from and input to an unnamed coprocess (@pxref{Coprocesses}).
+
+@item DIRSTACK
+An array variable containing the current contents of the directory stack.
+Directories appear in the stack in the order they are displayed by the
+@code{dirs} builtin.
+Assigning to members of this array variable may be used to modify
+directories already in the stack, but the @code{pushd} and @code{popd}
+builtins must be used to add and remove directories.
+Assignment to this variable will not change the current directory.
+If @env{DIRSTACK} is unset, it loses its special properties, even if
+it is subsequently reset.
+
+@item EMACS
+If Bash finds this variable in the environment when the shell
+starts with value @samp{t}, it assumes that the shell is running in an
+Emacs shell buffer and disables line editing.
+
+@item ENV
+Similar to @code{BASH_ENV}; used when the shell is invoked in
+@sc{posix} Mode (@pxref{Bash POSIX Mode}).
+
+@item EUID
+The numeric effective user id of the current user. This variable
+is readonly.
+
+@item FCEDIT
+The editor used as a default by the @option{-e} option to the @code{fc}
+builtin command.
+
+@item FIGNORE
+A colon-separated list of suffixes to ignore when performing
+filename completion.
+A filename whose suffix matches one of the entries in
+@env{FIGNORE}
+is excluded from the list of matched filenames. A sample
+value is @samp{.o:~}
+
+@item FUNCNAME
+An array variable containing the names of all shell functions
+currently in the execution call stack.
+The element with index 0 is the name of any currently-executing
+shell function.
+The bottom-most element (the one with the highest index)
+is @code{"main"}.
+This variable exists only when a shell function is executing.
+Assignments to @env{FUNCNAME} have no effect and return an error status.
+If @env{FUNCNAME} is unset, it loses its special properties, even if
+it is subsequently reset.
+
+This variable can be used with @code{BASH_LINENO} and @code{BASH_SOURCE}.
+Each element of @code{FUNCNAME} has corresponding elements in
+@code{BASH_LINENO} and @code{BASH_SOURCE} to describe the call stack.
+For instance, @code{$@{FUNCNAME[$i]@}} was called from the file
+@code{$@{BASH_SOURCE[$i+1]@}} at line number @code{$@{BASH_LINENO[$i]@}}.
+The @code{caller} builtin displays the current call stack using this
+information.
+
+@item FUNCNEST
+If set to a numeric value greater than 0, defines a maximum function
+nesting level. Function invocations that exceed this nesting level
+will cause the current command to abort.
+
+@item GLOBIGNORE
+A colon-separated list of patterns defining the set of filenames to
+be ignored by filename expansion.
+If a filename matched by a filename expansion pattern also matches one
+of the patterns in @env{GLOBIGNORE}, it is removed from the list
+of matches.
+
+@item GROUPS
+An array variable containing the list of groups of which the current
+user is a member.
+Assignments to @env{GROUPS} have no effect and return an error status.
+If @env{GROUPS} is unset, it loses its special properties, even if it is
+subsequently reset.
+
+@item histchars
+Up to three characters which control history expansion, quick
+substitution, and tokenization (@pxref{History Interaction}).
+The first character is the
+@var{history expansion} character, that is, the character which signifies the
+start of a history expansion, normally @samp{!}. The second character is the
+character which signifies `quick substitution' when seen as the first
+character on a line, normally @samp{^}. The optional third character is the
+character which indicates that the remainder of the line is a comment when
+found as the first character of a word, usually @samp{#}. The history
+comment character causes history substitution to be skipped for the
+remaining words on the line. It does not necessarily cause the shell
+parser to treat the rest of the line as a comment.
+
+@item HISTCMD
+The history number, or index in the history list, of the current
+command. If @env{HISTCMD} is unset, it loses its special properties,
+even if it is subsequently reset.
+
+@item HISTCONTROL
+A colon-separated list of values controlling how commands are saved on
+the history list.
+If the list of values includes @samp{ignorespace}, lines which begin
+with a space character are not saved in the history list.
+A value of @samp{ignoredups} causes lines which match the previous
+history entry to not be saved.
+A value of @samp{ignoreboth} is shorthand for
+@samp{ignorespace} and @samp{ignoredups}.
+A value of @samp{erasedups} causes all previous lines matching the
+current line to be removed from the history list before that line
+is saved.
+Any value not in the above list is ignored.
+If @env{HISTCONTROL} is unset, or does not include a valid value,
+all lines read by the shell parser are saved on the history list,
+subject to the value of @env{HISTIGNORE}.
+The second and subsequent lines of a multi-line compound command are
+not tested, and are added to the history regardless of the value of
+@env{HISTCONTROL}.
+
+@item HISTFILE
+The name of the file to which the command history is saved. The
+default value is @file{~/.bash_history}.
+
+@item HISTFILESIZE
+The maximum number of lines contained in the history file.
+When this variable is assigned a value, the history file is truncated,
+if necessary, to contain no more than that number of lines
+by removing the oldest entries.
+The history file is also truncated to this size after
+writing it when a shell exits.
+If the value is 0, the history file is truncated to zero size.
+Non-numeric values and numeric values less than zero inhibit truncation.
+The shell sets the default value to the value of @env{HISTSIZE}
+after reading any startup files.
+
+@item HISTIGNORE
+A colon-separated list of patterns used to decide which command
+lines should be saved on the history list. Each pattern is
+anchored at the beginning of the line and must match the complete
+line (no implicit @samp{*} is appended). Each pattern is tested
+against the line after the checks specified by @env{HISTCONTROL}
+are applied. In addition to the normal shell pattern matching
+characters, @samp{&} matches the previous history line. @samp{&}
+may be escaped using a backslash; the backslash is removed
+before attempting a match.
+The second and subsequent lines of a multi-line compound command are
+not tested, and are added to the history regardless of the value of
+@env{HISTIGNORE}.
+
+@env{HISTIGNORE} subsumes the function of @env{HISTCONTROL}. A
+pattern of @samp{&} is identical to @code{ignoredups}, and a
+pattern of @samp{[ ]*} is identical to @code{ignorespace}.
+Combining these two patterns, separating them with a colon,
+provides the functionality of @code{ignoreboth}.
+
+@item HISTSIZE
+The maximum number of commands to remember on the history list.
+If the value is 0, commands are not saved in the history list.
+Numeric values less than zero result in every command being saved
+on the history list (there is no limit).
+The shell sets the default value to 500 after reading any startup files.
+
+@item HISTTIMEFORMAT
+If this variable is set and not null, its value is used as a format string
+for @var{strftime} to print the time stamp associated with each history
+entry displayed by the @code{history} builtin.
+If this variable is set, time stamps are written to the history file so
+they may be preserved across shell sessions.
+This uses the history comment character to distinguish timestamps from
+other history lines.
+
+@item HOSTFILE
+Contains the name of a file in the same format as @file{/etc/hosts} that
+should be read when the shell needs to complete a hostname.
+The list of possible hostname completions may be changed while the shell
+is running;
+the next time hostname completion is attempted after the
+value is changed, Bash adds the contents of the new file to the
+existing list.
+If @env{HOSTFILE} is set, but has no value, or does not name a readable file,
+Bash attempts to read
+@file{/etc/hosts} to obtain the list of possible hostname completions.
+When @env{HOSTFILE} is unset, the hostname list is cleared.
+
+@item HOSTNAME
+The name of the current host.
+
+@item HOSTTYPE
+A string describing the machine Bash is running on.
+
+@item IGNOREEOF
+Controls the action of the shell on receipt of an @code{EOF} character
+as the sole input. If set, the value denotes the number
+of consecutive @code{EOF} characters that can be read as the
+first character on an input line
+before the shell will exit. If the variable exists but does not
+have a numeric value (or has no value) then the default is 10.
+If the variable does not exist, then @code{EOF} signifies the end of
+input to the shell. This is only in effect for interactive shells.
+
+@item INPUTRC
+The name of the Readline initialization file, overriding the default
+of @file{~/.inputrc}.
+
+@item LANG
+Used to determine the locale category for any category not specifically
+selected with a variable starting with @code{LC_}.
+
+@item LC_ALL
+This variable overrides the value of @env{LANG} and any other
+@code{LC_} variable specifying a locale category.
+
+@item LC_COLLATE
+This variable determines the collation order used when sorting the
+results of filename expansion, and
+determines the behavior of range expressions, equivalence classes,
+and collating sequences within filename expansion and pattern matching
+(@pxref{Filename Expansion}).
+
+@item LC_CTYPE
+This variable determines the interpretation of characters and the
+behavior of character classes within filename expansion and pattern
+matching (@pxref{Filename Expansion}).
+
+@item LC_MESSAGES
+This variable determines the locale used to translate double-quoted
+strings preceded by a @samp{$} (@pxref{Locale Translation}).
+
+@item LC_NUMERIC
+This variable determines the locale category used for number formatting.
+
+@item LINENO
+The line number in the script or shell function currently executing.
+
+@item LINES
+Used by the @code{select} command to determine the column length
+for printing selection lists.
+Automatically set if the @code{checkwinsize} option is enabled
+(@pxref{The Shopt Builtin}), or in an interactive shell upon receipt of a
+@code{SIGWINCH}.
+
+@item MACHTYPE
+A string that fully describes the system type on which Bash
+is executing, in the standard @sc{gnu} @var{cpu-company-system} format.
+
+@item MAILCHECK
+How often (in seconds) that the shell should check for mail in the
+files specified in the @env{MAILPATH} or @env{MAIL} variables.
+The default is 60 seconds. When it is time to check
+for mail, the shell does so before displaying the primary prompt.
+If this variable is unset, or set to a value that is not a number
+greater than or equal to zero, the shell disables mail checking.
+
+@item MAPFILE
+An array variable created to hold the text read by the
+@code{mapfile} builtin when no variable name is supplied.
+
+@item OLDPWD
+The previous working directory as set by the @code{cd} builtin.
+
+@item OPTERR
+If set to the value 1, Bash displays error messages
+generated by the @code{getopts} builtin command.
+
+@item OSTYPE
+A string describing the operating system Bash is running on.
+
+@item PIPESTATUS
+An array variable (@pxref{Arrays})
+containing a list of exit status values from the processes
+in the most-recently-executed foreground pipeline (which may
+contain only a single command).
+
+@item POSIXLY_CORRECT
+If this variable is in the environment when Bash starts, the shell
+enters @sc{posix} mode (@pxref{Bash POSIX Mode}) before reading the
+startup files, as if the @option{--posix} invocation option had been supplied.
+If it is set while the shell is running, Bash enables @sc{posix} mode,
+as if the command
+@example
+@code{set -o posix}
+@end example
+@noindent
+had been executed.
+
+@item PPID
+The process @sc{id} of the shell's parent process. This variable
+is readonly.
+
+@item PROMPT_COMMAND
+If set, the value is interpreted as a command to execute
+before the printing of each primary prompt (@env{$PS1}).
+
+@item PROMPT_DIRTRIM
+If set to a number greater than zero, the value is used as the number of
+trailing directory components to retain when expanding the @code{\w} and
+@code{\W} prompt string escapes (@pxref{Controlling the Prompt}).
+Characters removed are replaced with an ellipsis.
+
+@item PS3
+The value of this variable is used as the prompt for the
+@code{select} command. If this variable is not set, the
+@code{select} command prompts with @samp{#? }
+
+@item PS4
+The value is the prompt printed before the command line is echoed
+when the @option{-x} option is set (@pxref{The Set Builtin}).
+The first character of @env{PS4} is replicated multiple times, as
+necessary, to indicate multiple levels of indirection.
+The default is @samp{+ }.
+
+@item PWD
+The current working directory as set by the @code{cd} builtin.
+
+@item RANDOM
+Each time this parameter is referenced, a random integer
+between 0 and 32767 is generated. Assigning a value to this
+variable seeds the random number generator.
+
+@item READLINE_LINE
+The contents of the Readline line buffer, for use
+with @samp{bind -x} (@pxref{Bash Builtins}).
+
+@item READLINE_POINT
+The position of the insertion point in the Readline line buffer, for use
+with @samp{bind -x} (@pxref{Bash Builtins}).
+
+@item REPLY
+The default variable for the @code{read} builtin.
+
+@item SECONDS
+This variable expands to the number of seconds since the
+shell was started. Assignment to this variable resets
+the count to the value assigned, and the expanded value
+becomes the value assigned plus the number of seconds
+since the assignment.
+
+@item SHELL
+The full pathname to the shell is kept in this environment variable.
+If it is not set when the shell starts,
+Bash assigns to it the full pathname of the current user's login shell.
+
+@item SHELLOPTS
+A colon-separated list of enabled shell options. Each word in
+the list is a valid argument for the @option{-o} option to the
+@code{set} builtin command (@pxref{The Set Builtin}).
+The options appearing in @env{SHELLOPTS} are those reported
+as @samp{on} by @samp{set -o}.
+If this variable is in the environment when Bash
+starts up, each shell option in the list will be enabled before
+reading any startup files. This variable is readonly.
+
+@item SHLVL
+Incremented by one each time a new instance of Bash is started. This is
+intended to be a count of how deeply your Bash shells are nested.
+
+@item TIMEFORMAT
+The value of this parameter is used as a format string specifying
+how the timing information for pipelines prefixed with the @code{time}
+reserved word should be displayed.
+The @samp{%} character introduces an
+escape sequence that is expanded to a time value or other
+information.
+The escape sequences and their meanings are as
+follows; the braces denote optional portions.
+
+@table @code
+
+@item %%
+A literal @samp{%}.
+
+@item %[@var{p}][l]R
+The elapsed time in seconds.
+
+@item %[@var{p}][l]U
+The number of CPU seconds spent in user mode.
+
+@item %[@var{p}][l]S
+The number of CPU seconds spent in system mode.
+
+@item %P
+The CPU percentage, computed as (%U + %S) / %R.
+@end table
+
+The optional @var{p} is a digit specifying the precision, the number of
+fractional digits after a decimal point.
+A value of 0 causes no decimal point or fraction to be output.
+At most three places after the decimal point may be specified; values
+of @var{p} greater than 3 are changed to 3.
+If @var{p} is not specified, the value 3 is used.
+
+The optional @code{l} specifies a longer format, including minutes, of
+the form @var{MM}m@var{SS}.@var{FF}s.
+The value of @var{p} determines whether or not the fraction is included.
+
+If this variable is not set, Bash acts as if it had the value
+@example
+@code{$'\nreal\t%3lR\nuser\t%3lU\nsys\t%3lS'}
+@end example
+If the value is null, no timing information is displayed.
+A trailing newline is added when the format string is displayed.
+
+@item TMOUT
+If set to a value greater than zero, @code{TMOUT} is treated as the
+default timeout for the @code{read} builtin (@pxref{Bash Builtins}).
+The @code{select} command (@pxref{Conditional Constructs}) terminates
+if input does not arrive after @code{TMOUT} seconds when input is coming
+from a terminal.
+
+In an interactive shell, the value is interpreted as
+the number of seconds to wait for a line of input after issuing
+the primary prompt.
+Bash
+terminates after waiting for that number of seconds if a complete
+line of input does not arrive.
+
+@item TMPDIR
+If set, Bash uses its value as the name of a directory in which
+Bash creates temporary files for the shell's use.
+
+@item UID
+The numeric real user id of the current user. This variable is readonly.
+
+@end vtable
+
+@node Bash Features
+@chapter Bash Features
+
+This chapter describes features unique to Bash.
+
+@menu
+* Invoking Bash:: Command line options that you can give
+ to Bash.
+* Bash Startup Files:: When and how Bash executes scripts.
+* Interactive Shells:: What an interactive shell is.
+* Bash Conditional Expressions:: Primitives used in composing expressions for
+ the @code{test} builtin.
+* Shell Arithmetic:: Arithmetic on shell variables.
+* Aliases:: Substituting one command for another.
+* Arrays:: Array Variables.
+* The Directory Stack:: History of visited directories.
+* Controlling the Prompt:: Customizing the various prompt strings.
+* The Restricted Shell:: A more controlled mode of shell execution.
+* Bash POSIX Mode:: Making Bash behave more closely to what
+ the POSIX standard specifies.
+@end menu
+
+@node Invoking Bash
+@section Invoking Bash
+
+@example
+bash [long-opt] [-ir] [-abefhkmnptuvxdBCDHP] [-o @var{option}] [-O @var{shopt_option}] [@var{argument} @dots{}]
+bash [long-opt] [-abefhkmnptuvxdBCDHP] [-o @var{option}] [-O @var{shopt_option}] -c @var{string} [@var{argument} @dots{}]
+bash [long-opt] -s [-abefhkmnptuvxdBCDHP] [-o @var{option}] [-O @var{shopt_option}] [@var{argument} @dots{}]
+@end example
+
+All of the single-character options used with the @code{set} builtin
+(@pxref{The Set Builtin}) can be used as options when the shell is invoked.
+In addition, there are several multi-character
+options that you can use. These options must appear on the command
+line before the single-character options to be recognized.
+
+@table @code
+@item --debugger
+Arrange for the debugger profile to be executed before the shell
+starts. Turns on extended debugging mode (see @ref{The Shopt Builtin}
+for a description of the @code{extdebug} option to the @code{shopt}
+builtin).
+
+@item --dump-po-strings
+A list of all double-quoted strings preceded by @samp{$}
+is printed on the standard output
+in the @sc{gnu} @code{gettext} PO (portable object) file format.
+Equivalent to @option{-D} except for the output format.
+
+@item --dump-strings
+Equivalent to @option{-D}.
+
+@item --help
+Display a usage message on standard output and exit successfully.
+
+@item --init-file @var{filename}
+@itemx --rcfile @var{filename}
+Execute commands from @var{filename} (instead of @file{~/.bashrc})
+in an interactive shell.
+
+@item --login
+Equivalent to @option{-l}.
+
+@item --noediting
+Do not use the @sc{gnu} Readline library (@pxref{Command Line Editing})
+to read command lines when the shell is interactive.
+
+@item --noprofile
+Don't load the system-wide startup file @file{/etc/profile}
+or any of the personal initialization files
+@file{~/.bash_profile}, @file{~/.bash_login}, or @file{~/.profile}
+when Bash is invoked as a login shell.
+
+@item --norc
+Don't read the @file{~/.bashrc} initialization file in an
+interactive shell. This is on by default if the shell is
+invoked as @code{sh}.
+
+@item --posix
+Change the behavior of Bash where the default operation differs
+from the @sc{posix} standard to match the standard. This
+is intended to make Bash behave as a strict superset of that
+standard. @xref{Bash POSIX Mode}, for a description of the Bash
+@sc{posix} mode.
+
+@item --restricted
+Make the shell a restricted shell (@pxref{The Restricted Shell}).
+
+@item --verbose
+Equivalent to @option{-v}. Print shell input lines as they're read.
+
+@item --version
+Show version information for this instance of
+Bash on the standard output and exit successfully.
+@end table
+
+There are several single-character options that may be supplied at
+invocation which are not available with the @code{set} builtin.
+
+@table @code
+@item -c
+Read and execute commands from the first non-option argument
+@var{command_string}, then exit.
+If there are arguments after the @var{command_string},
+the first argument is assigned to @code{$0}
+and any remaining arguments are assigned to the positional parameters.
+The assignment to @code{$0} sets the name of the shell, which is used
+in warning and error messages.
+
+@item -i
+Force the shell to run interactively. Interactive shells are
+described in @ref{Interactive Shells}.
+
+@item -l
+Make this shell act as if it had been directly invoked by login.
+When the shell is interactive, this is equivalent to starting a
+login shell with @samp{exec -l bash}.
+When the shell is not interactive, the login shell startup files will
+be executed.
+@samp{exec bash -l} or @samp{exec bash --login}
+will replace the current shell with a Bash login shell.
+@xref{Bash Startup Files}, for a description of the special behavior
+of a login shell.
+
+@item -r
+Make the shell a restricted shell (@pxref{The Restricted Shell}).
+
+@item -s
+If this option is present, or if no arguments remain after option
+processing, then commands are read from the standard input.
+This option allows the positional parameters to be set
+when invoking an interactive shell.
+
+@item -D
+A list of all double-quoted strings preceded by @samp{$}
+is printed on the standard output.
+These are the strings that
+are subject to language translation when the current locale
+is not @code{C} or @code{POSIX} (@pxref{Locale Translation}).
+This implies the @option{-n} option; no commands will be executed.
+
+@item [-+]O [@var{shopt_option}]
+@var{shopt_option} is one of the shell options accepted by the
+@code{shopt} builtin (@pxref{The Shopt Builtin}).
+If @var{shopt_option} is present, @option{-O} sets the value of that option;
+@option{+O} unsets it.
+If @var{shopt_option} is not supplied, the names and values of the shell
+options accepted by @code{shopt} are printed on the standard output.
+If the invocation option is @option{+O}, the output is displayed in a format
+that may be reused as input.
+
+@item --
+A @code{--} signals the end of options and disables further option
+processing.
+Any arguments after the @code{--} are treated as filenames and arguments.
+@end table
+
+@cindex login shell
+A @emph{login} shell is one whose first character of argument zero is
+@samp{-}, or one invoked with the @option{--login} option.
+
+@cindex interactive shell
+An @emph{interactive} shell is one started without non-option arguments,
+unless @option{-s} is specified,
+without specifying the @option{-c} option, and whose input and output are both
+connected to terminals (as determined by @code{isatty(3)}), or one
+started with the @option{-i} option. @xref{Interactive Shells}, for more
+information.
+
+If arguments remain after option processing, and neither the
+@option{-c} nor the @option{-s}
+option has been supplied, the first argument is assumed to
+be the name of a file containing shell commands (@pxref{Shell Scripts}).
+When Bash is invoked in this fashion, @code{$0}
+is set to the name of the file, and the positional parameters
+are set to the remaining arguments.
+Bash reads and executes commands from this file, then exits.
+Bash's exit status is the exit status of the last command executed
+in the script. If no commands are executed, the exit status is 0.
+
+@node Bash Startup Files
+@section Bash Startup Files
+@cindex startup files
+
+This section describes how Bash executes its startup files.
+If any of the files exist but cannot be read, Bash reports an error.
+Tildes are expanded in filenames as described above under
+Tilde Expansion (@pxref{Tilde Expansion}).
+
+Interactive shells are described in @ref{Interactive Shells}.
+
+@subsubheading Invoked as an interactive login shell, or with @option{--login}
+
+When Bash is invoked as an interactive login shell, or as a
+non-interactive shell with the @option{--login} option, it first reads and
+executes commands from the file @file{/etc/profile}, if that file exists.
+After reading that file, it looks for @file{~/.bash_profile},
+@file{~/.bash_login}, and @file{~/.profile}, in that order, and reads
+and executes commands from the first one that exists and is readable.
+The @option{--noprofile} option may be used when the shell is started to
+inhibit this behavior.
+
+When a login shell exits, Bash reads and executes commands from
+the file @file{~/.bash_logout}, if it exists.
+
+@subsubheading Invoked as an interactive non-login shell
+
+When an interactive shell that is not a login shell is started, Bash
+reads and executes commands from @file{~/.bashrc}, if that file exists.
+This may be inhibited by using the @option{--norc} option.
+The @option{--rcfile @var{file}} option will force Bash to read and
+execute commands from @var{file} instead of @file{~/.bashrc}.
+
+So, typically, your @file{~/.bash_profile} contains the line
+@example
+@code{if [ -f ~/.bashrc ]; then . ~/.bashrc; fi}
+@end example
+@noindent
+after (or before) any login-specific initializations.
+
+@subsubheading Invoked non-interactively
+
+When Bash is started non-interactively, to run a shell script,
+for example, it looks for the variable @env{BASH_ENV} in the environment,
+expands its value if it appears there, and uses the expanded value as
+the name of a file to read and execute. Bash behaves as if the
+following command were executed:
+@example
+@code{if [ -n "$BASH_ENV" ]; then . "$BASH_ENV"; fi}
+@end example
+@noindent
+but the value of the @env{PATH} variable is not used to search for the
+filename.
+
+As noted above, if a non-interactive shell is invoked with the
+@option{--login} option, Bash attempts to read and execute commands from the
+login shell startup files.
+
+@subsubheading Invoked with name @code{sh}
+
+If Bash is invoked with the name @code{sh}, it tries to mimic the
+startup behavior of historical versions of @code{sh} as closely as
+possible, while conforming to the @sc{posix} standard as well.
+
+When invoked as an interactive login shell, or as a non-interactive
+shell with the @option{--login} option, it first attempts to read
+and execute commands from @file{/etc/profile} and @file{~/.profile}, in
+that order.
+The @option{--noprofile} option may be used to inhibit this behavior.
+When invoked as an interactive shell with the name @code{sh}, Bash
+looks for the variable @env{ENV}, expands its value if it is defined,
+and uses the expanded value as the name of a file to read and execute.
+Since a shell invoked as @code{sh} does not attempt to read and execute
+commands from any other startup files, the @option{--rcfile} option has
+no effect.
+A non-interactive shell invoked with the name @code{sh} does not attempt
+to read any other startup files.
+
+When invoked as @code{sh}, Bash enters @sc{posix} mode after
+the startup files are read.
+
+@subsubheading Invoked in @sc{posix} mode
+
+When Bash is started in @sc{posix} mode, as with the
+@option{--posix} command line option, it follows the @sc{posix} standard
+for startup files.
+In this mode, interactive shells expand the @env{ENV} variable
+and commands are read and executed from the file whose name is the
+expanded value.
+No other startup files are read.
+
+@subsubheading Invoked by remote shell daemon
+
+Bash attempts to determine when it is being run with its standard input
+connected to a network connection, as when executed by the remote shell
+daemon, usually @code{rshd}, or the secure shell daemon @code{sshd}.
+If Bash determines it is being run in
+this fashion, it reads and executes commands from @file{~/.bashrc}, if that
+file exists and is readable.
+It will not do this if invoked as @code{sh}.
+The @option{--norc} option may be used to inhibit this behavior, and the
+@option{--rcfile} option may be used to force another file to be read, but
+neither @code{rshd} nor @code{sshd} generally invoke the shell with those
+options or allow them to be specified.
+
+@subsubheading Invoked with unequal effective and real @sc{uid/gid}s
+
+If Bash is started with the effective user (group) id not equal to the
+real user (group) id, and the @option{-p} option is not supplied, no startup
+files are read, shell functions are not inherited from the environment,
+the @env{SHELLOPTS}, @env{BASHOPTS}, @env{CDPATH}, and @env{GLOBIGNORE}
+variables, if they appear in the environment, are ignored, and the effective
+user id is set to the real user id.
+If the @option{-p} option is supplied at invocation, the startup behavior is
+the same, but the effective user id is not reset.
+
+@node Interactive Shells
+@section Interactive Shells
+@cindex interactive shell
+@cindex shell, interactive
+
+@menu
+* What is an Interactive Shell?:: What determines whether a shell is Interactive.
+* Is this Shell Interactive?:: How to tell if a shell is interactive.
+* Interactive Shell Behavior:: What changes in a interactive shell?
+@end menu
+
+@node What is an Interactive Shell?
+@subsection What is an Interactive Shell?
+
+An interactive shell
+is one started without non-option arguments, unless @option{-s} is
+specified, without specifying the @option{-c} option, and
+whose input and error output are both
+connected to terminals (as determined by @code{isatty(3)}),
+or one started with the @option{-i} option.
+
+An interactive shell generally reads from and writes to a user's
+terminal.
+
+The @option{-s} invocation option may be used to set the positional parameters
+when an interactive shell is started.
+
+@node Is this Shell Interactive?
+@subsection Is this Shell Interactive?
+
+To determine within a startup script whether or not Bash is
+running interactively,
+test the value of the @samp{-} special parameter.
+It contains @code{i} when the shell is interactive. For example:
+
+@example
+case "$-" in
+*i*) echo This shell is interactive ;;
+*) echo This shell is not interactive ;;
+esac
+@end example
+
+Alternatively, startup scripts may examine the variable
+@env{PS1}; it is unset in non-interactive shells, and set in
+interactive shells. Thus:
+
+@example
+if [ -z "$PS1" ]; then
+ echo This shell is not interactive
+else
+ echo This shell is interactive
+fi
+@end example
+
+@node Interactive Shell Behavior
+@subsection Interactive Shell Behavior
+
+When the shell is running interactively, it changes its behavior in
+several ways.
+
+@enumerate
+@item
+Startup files are read and executed as described in @ref{Bash Startup Files}.
+
+@item
+Job Control (@pxref{Job Control}) is enabled by default. When job
+control is in effect, Bash ignores the keyboard-generated job control
+signals @code{SIGTTIN}, @code{SIGTTOU}, and @code{SIGTSTP}.
+
+@item
+Bash expands and displays @env{PS1} before reading the first line
+of a command, and expands and displays @env{PS2} before reading the
+second and subsequent lines of a multi-line command.
+
+@item
+Bash executes the value of the @env{PROMPT_COMMAND} variable as a command
+before printing the primary prompt, @env{$PS1}
+(@pxref{Bash Variables}).
+
+@item
+Readline (@pxref{Command Line Editing}) is used to read commands from
+the user's terminal.
+
+@item
+Bash inspects the value of the @code{ignoreeof} option to @code{set -o}
+instead of exiting immediately when it receives an @code{EOF} on its
+standard input when reading a command (@pxref{The Set Builtin}).
+
+@item
+Command history (@pxref{Bash History Facilities})
+and history expansion (@pxref{History Interaction})
+are enabled by default.
+Bash will save the command history to the file named by @env{$HISTFILE}
+when a shell with history enabled exits.
+
+@item
+Alias expansion (@pxref{Aliases}) is performed by default.
+
+@item
+In the absence of any traps, Bash ignores @code{SIGTERM}
+(@pxref{Signals}).
+
+@item
+In the absence of any traps, @code{SIGINT} is caught and handled
+((@pxref{Signals}).
+@code{SIGINT} will interrupt some shell builtins.
+
+@item
+An interactive login shell sends a @code{SIGHUP} to all jobs on exit
+if the @code{huponexit} shell option has been enabled (@pxref{Signals}).
+
+@item
+The @option{-n} invocation option is ignored, and @samp{set -n} has
+no effect (@pxref{The Set Builtin}).
+
+@item
+Bash will check for mail periodically, depending on the values of the
+@env{MAIL}, @env{MAILPATH}, and @env{MAILCHECK} shell variables
+(@pxref{Bash Variables}).
+
+@item
+Expansion errors due to references to unbound shell variables after
+@samp{set -u} has been enabled will not cause the shell to exit
+(@pxref{The Set Builtin}).
+
+@item
+The shell will not exit on expansion errors caused by @var{var} being unset
+or null in @code{$@{@var{var}:?@var{word}@}} expansions
+(@pxref{Shell Parameter Expansion}).
+
+@item
+Redirection errors encountered by shell builtins will not cause the
+shell to exit.
+
+@item
+When running in @sc{posix} mode, a special builtin returning an error
+status will not cause the shell to exit (@pxref{Bash POSIX Mode}).
+
+@item
+A failed @code{exec} will not cause the shell to exit
+(@pxref{Bourne Shell Builtins}).
+
+@item
+Parser syntax errors will not cause the shell to exit.
+
+@item
+Simple spelling correction for directory arguments to the @code{cd}
+builtin is enabled by default (see the description of the @code{cdspell}
+option to the @code{shopt} builtin in @ref{The Shopt Builtin}).
+
+@item
+The shell will check the value of the @env{TMOUT} variable and exit
+if a command is not read within the specified number of seconds after
+printing @env{$PS1} (@pxref{Bash Variables}).
+
+@end enumerate
+
+@node Bash Conditional Expressions
+@section Bash Conditional Expressions
+@cindex expressions, conditional
+
+Conditional expressions are used by the @code{[[} compound command
+and the @code{test} and @code{[} builtin commands.
+
+Expressions may be unary or binary.
+Unary expressions are often used to examine the status of a file.
+There are string operators and numeric comparison operators as well.
+If the @var{file} argument to one of the primaries is of the form
+@file{/dev/fd/@var{N}}, then file descriptor @var{N} is checked.
+If the @var{file} argument to one of the primaries is one of
+@file{/dev/stdin}, @file{/dev/stdout}, or @file{/dev/stderr}, file
+descriptor 0, 1, or 2, respectively, is checked.
+
+When used with @code{[[}, the @samp{<} and @samp{>} operators sort
+lexicographically using the current locale.
+The @code{test} command uses ASCII ordering.
+
+Unless otherwise specified, primaries that operate on files follow symbolic
+links and operate on the target of the link, rather than the link itself.
+
+@table @code
+@item -a @var{file}
+True if @var{file} exists.
+
+@item -b @var{file}
+True if @var{file} exists and is a block special file.
+
+@item -c @var{file}
+True if @var{file} exists and is a character special file.
+
+@item -d @var{file}
+True if @var{file} exists and is a directory.
+
+@item -e @var{file}
+True if @var{file} exists.
+
+@item -f @var{file}
+True if @var{file} exists and is a regular file.
+
+@item -g @var{file}
+True if @var{file} exists and its set-group-id bit is set.
+
+@item -h @var{file}
+True if @var{file} exists and is a symbolic link.
+
+@item -k @var{file}
+True if @var{file} exists and its "sticky" bit is set.
+
+@item -p @var{file}
+True if @var{file} exists and is a named pipe (FIFO).
+
+@item -r @var{file}
+True if @var{file} exists and is readable.
+
+@item -s @var{file}
+True if @var{file} exists and has a size greater than zero.
+
+@item -t @var{fd}
+True if file descriptor @var{fd} is open and refers to a terminal.
+
+@item -u @var{file}
+True if @var{file} exists and its set-user-id bit is set.
+
+@item -w @var{file}
+True if @var{file} exists and is writable.
+
+@item -x @var{file}
+True if @var{file} exists and is executable.
+
+@item -G @var{file}
+True if @var{file} exists and is owned by the effective group id.
+
+@item -L @var{file}
+True if @var{file} exists and is a symbolic link.
+
+@item -N @var{file}
+True if @var{file} exists and has been modified since it was last read.
+
+@item -O @var{file}
+True if @var{file} exists and is owned by the effective user id.
+
+@item -S @var{file}
+True if @var{file} exists and is a socket.
+
+@item @var{file1} -ef @var{file2}
+True if @var{file1} and @var{file2} refer to the same device and
+inode numbers.
+
+@item @var{file1} -nt @var{file2}
+True if @var{file1} is newer (according to modification date)
+than @var{file2}, or if @var{file1} exists and @var{file2} does not.
+
+@item @var{file1} -ot @var{file2}
+True if @var{file1} is older than @var{file2},
+or if @var{file2} exists and @var{file1} does not.
+
+@item -o @var{optname}
+True if the shell option @var{optname} is enabled.
+The list of options appears in the description of the @option{-o}
+option to the @code{set} builtin (@pxref{The Set Builtin}).
+
+@item -v @var{varname}
+True if the shell variable @var{varname} is set (has been assigned a value).
+
+@item -R @var{varname}
+True if the shell variable @var{varname} is set and is a name reference.
+
+@item -z @var{string}
+True if the length of @var{string} is zero.
+
+@item -n @var{string}
+@itemx @var{string}
+True if the length of @var{string} is non-zero.
+
+@item @var{string1} == @var{string2}
+@itemx @var{string1} = @var{string2}
+True if the strings are equal.
+When used with the @code{[[} command, this performs pattern matching as
+described above (@pxref{Conditional Constructs}).
+
+@samp{=} should be used with the @code{test} command for @sc{posix} conformance.
+
+@item @var{string1} != @var{string2}
+True if the strings are not equal.
+
+@item @var{string1} < @var{string2}
+True if @var{string1} sorts before @var{string2} lexicographically.
+
+@item @var{string1} > @var{string2}
+True if @var{string1} sorts after @var{string2} lexicographically.
+
+@item @var{arg1} OP @var{arg2}
+@code{OP} is one of
+@samp{-eq}, @samp{-ne}, @samp{-lt}, @samp{-le}, @samp{-gt}, or @samp{-ge}.
+These arithmetic binary operators return true if @var{arg1}
+is equal to, not equal to, less than, less than or equal to,
+greater than, or greater than or equal to @var{arg2},
+respectively. @var{Arg1} and @var{arg2}
+may be positive or negative integers.
+@end table
+
+@node Shell Arithmetic
+@section Shell Arithmetic
+@cindex arithmetic, shell
+@cindex shell arithmetic
+@cindex expressions, arithmetic
+@cindex evaluation, arithmetic
+@cindex arithmetic evaluation
+
+The shell allows arithmetic expressions to be evaluated, as one of
+the shell expansions or by the @code{let} and the @option{-i} option
+to the @code{declare} builtins.
+
+Evaluation is done in fixed-width integers with no check for overflow,
+though division by 0 is trapped and flagged as an error.
+The operators and their precedence, associativity, and values
+are the same as in the C language.
+The following list of operators is grouped into levels of
+equal-precedence operators.
+The levels are listed in order of decreasing precedence.
+
+@table @code
+
+@item @var{id}++ @var{id}--
+variable post-increment and post-decrement
+
+@item ++@var{id} --@var{id}
+variable pre-increment and pre-decrement
+
+@item - +
+unary minus and plus
+
+@item ! ~
+logical and bitwise negation
+
+@item **
+exponentiation
+
+@item * / %
+multiplication, division, remainder
+
+@item + -
+addition, subtraction
+
+@item << >>
+left and right bitwise shifts
+
+@item <= >= < >
+comparison
+
+@item == !=
+equality and inequality
+
+@item &
+bitwise AND
+
+@item ^
+bitwise exclusive OR
+
+@item |
+bitwise OR
+
+@item &&
+logical AND
+
+@item ||
+logical OR
+
+@item expr ? expr : expr
+conditional operator
+
+@item = *= /= %= += -= <<= >>= &= ^= |=
+assignment
+
+@item expr1 , expr2
+comma
+@end table
+
+Shell variables are allowed as operands; parameter expansion is
+performed before the expression is evaluated.
+Within an expression, shell variables may also be referenced by name
+without using the parameter expansion syntax.
+A shell variable that is null or unset evaluates to 0 when referenced
+by name without using the parameter expansion syntax.
+The value of a variable is evaluated as an arithmetic expression
+when it is referenced, or when a variable which has been given the
+@var{integer} attribute using @samp{declare -i} is assigned a value.
+A null value evaluates to 0.
+A shell variable need not have its @var{integer} attribute turned on
+to be used in an expression.
+
+Constants with a leading 0 are interpreted as octal numbers.
+A leading @samp{0x} or @samp{0X} denotes hexadecimal. Otherwise,
+numbers take the form [@var{base}@code{#}]@var{n}, where the optional @var{base}
+is a decimal number between 2 and 64 representing the arithmetic
+base, and @var{n} is a number in that base.
+If @var{base}@code{#} is omitted, then base 10 is used.
+When specifying @var{n},
+he digits greater than 9 are represented by the lowercase letters,
+the uppercase letters, @samp{@@}, and @samp{_}, in that order.
+If @var{base} is less than or equal to 36, lowercase and uppercase
+letters may be used interchangeably to represent numbers between 10
+and 35.
+
+Operators are evaluated in order of precedence. Sub-expressions in
+parentheses are evaluated first and may override the precedence
+rules above.
+
+@node Aliases
+@section Aliases
+@cindex alias expansion
+
+@var{Aliases} allow a string to be substituted for a word when it is used
+as the first word of a simple command.
+The shell maintains a list of aliases that may be set and unset with
+the @code{alias} and @code{unalias} builtin commands.
+
+The first word of each simple command, if unquoted, is checked to see
+if it has an alias.
+If so, that word is replaced by the text of the alias.
+The characters @samp{/}, @samp{$}, @samp{`}, @samp{=} and any of the
+shell metacharacters or quoting characters listed above may not appear
+in an alias name.
+The replacement text may contain any valid
+shell input, including shell metacharacters.
+The first word of the replacement text is tested for
+aliases, but a word that is identical to an alias being expanded
+is not expanded a second time.
+This means that one may alias @code{ls} to @code{"ls -F"},
+for instance, and Bash does not try to recursively expand the
+replacement text.
+If the last character of the alias value is a
+@var{blank}, then the next command word following the
+alias is also checked for alias expansion.
+
+Aliases are created and listed with the @code{alias}
+command, and removed with the @code{unalias} command.
+
+There is no mechanism for using arguments in the replacement text,
+as in @code{csh}.
+If arguments are needed, a shell function should be used
+(@pxref{Shell Functions}).
+
+Aliases are not expanded when the shell is not interactive,
+unless the @code{expand_aliases} shell option is set using
+@code{shopt} (@pxref{The Shopt Builtin}).
+
+The rules concerning the definition and use of aliases are
+somewhat confusing. Bash
+always reads at least one complete line
+of input before executing any
+of the commands on that line. Aliases are expanded when a
+command is read, not when it is executed. Therefore, an
+alias definition appearing on the same line as another
+command does not take effect until the next line of input is read.
+The commands following the alias definition
+on that line are not affected by the new alias.
+This behavior is also an issue when functions are executed.
+Aliases are expanded when a function definition is read,
+not when the function is executed, because a function definition
+is itself a command. As a consequence, aliases
+defined in a function are not available until after that
+function is executed. To be safe, always put
+alias definitions on a separate line, and do not use @code{alias}
+in compound commands.
+
+For almost every purpose, shell functions are preferred over aliases.
+
+@node Arrays
+@section Arrays
+@cindex arrays
+
+Bash provides one-dimensional indexed and associative array variables.
+Any variable may be used as an indexed array;
+the @code{declare} builtin will explicitly declare an array.
+There is no maximum
+limit on the size of an array, nor any requirement that members
+be indexed or assigned contiguously.
+Indexed arrays are referenced using integers (including arithmetic
+expressions (@pxref{Shell Arithmetic})) and are zero-based;
+associative arrays use arbitrary strings.
+Unless otherwise noted, indexed array indices must be non-negative integers.
+
+An indexed array is created automatically if any variable is assigned to
+using the syntax
+@example
+@var{name}[@var{subscript}]=@var{value}
+@end example
+
+@noindent
+The @var{subscript}
+is treated as an arithmetic expression that must evaluate to a number.
+To explicitly declare an array, use
+@example
+declare -a @var{name}
+@end example
+@noindent
+The syntax
+@example
+declare -a @var{name}[@var{subscript}]
+@end example
+@noindent
+is also accepted; the @var{subscript} is ignored.
+
+@noindent
+Associative arrays are created using
+@example
+declare -A @var{name}.
+@end example
+
+Attributes may be
+specified for an array variable using the @code{declare} and
+@code{readonly} builtins. Each attribute applies to all members of
+an array.
+
+Arrays are assigned to using compound assignments of the form
+@example
+@var{name}=(@var{value1} @var{value2} @dots{} )
+@end example
+@noindent
+where each
+@var{value} is of the form @code{[@var{subscript}]=}@var{string}.
+Indexed array assignments do not require anything but @var{string}.
+When assigning to indexed arrays, if
+the optional subscript is supplied, that index is assigned to;
+otherwise the index of the element assigned is the last index assigned
+to by the statement plus one. Indexing starts at zero.
+
+When assigning to an associative array, the subscript is required.
+
+This syntax is also accepted by the @code{declare}
+builtin. Individual array elements may be assigned to using the
+@code{@var{name}[@var{subscript}]=@var{value}} syntax introduced above.
+
+When assigning to an indexed array, if @var{name}
+is subscripted by a negative number, that number is
+interpreted as relative to one greater than the maximum index of
+@var{name}, so negative indices count back from the end of the
+array, and an index of -1 references the last element.
+
+Any element of an array may be referenced using
+@code{$@{@var{name}[@var{subscript}]@}}.
+The braces are required to avoid
+conflicts with the shell's filename expansion operators. If the
+@var{subscript} is @samp{@@} or @samp{*}, the word expands to all members
+of the array @var{name}. These subscripts differ only when the word
+appears within double quotes.
+If the word is double-quoted,
+@code{$@{@var{name}[*]@}} expands to a single word with
+the value of each array member separated by the first character of the
+@env{IFS} variable, and @code{$@{@var{name}[@@]@}} expands each element of
+@var{name} to a separate word. When there are no array members,
+@code{$@{@var{name}[@@]@}} expands to nothing.
+If the double-quoted expansion occurs within a word, the expansion of
+the first parameter is joined with the beginning part of the original
+word, and the expansion of the last parameter is joined with the last
+part of the original word.
+This is analogous to the
+expansion of the special parameters @samp{@@} and @samp{*}.
+@code{$@{#@var{name}[@var{subscript}]@}} expands to the length of
+@code{$@{@var{name}[@var{subscript}]@}}.
+If @var{subscript} is @samp{@@} or
+@samp{*}, the expansion is the number of elements in the array.
+If the @var{subscript}
+used to reference an element of an indexed array
+evaluates to a number less than zero, it is
+interpreted as relative to one greater than the maximum index of the array,
+so negative indices count back from the end of the array,
+and an index of -1 refers to the last element.
+
+Referencing an array variable without a subscript is equivalent to
+referencing with a subscript of 0.
+Any reference to a variable using a valid subscript is legal, and
+@code{bash} will create an array if necessary.
+
+An array variable is considered set if a subscript has been assigned a
+value. The null string is a valid value.
+
+It is possible to obtain the keys (indices) of an array as well as the values.
+$@{!@var{name}[@@]@} and $@{!@var{name}[*]@} expand to the indices
+assigned in array variable @var{name}.
+The treatment when in double quotes is similar to the expansion of the
+special parameters @samp{@@} and @samp{*} within double quotes.
+
+The @code{unset} builtin is used to destroy arrays.
+@code{unset @var{name}[@var{subscript}]}
+destroys the array element at index @var{subscript}.
+Negative subscripts to indexed arrays are interpreted as described above.
+Care must be taken to avoid unwanted side effects caused by filename
+expansion.
+@code{unset @var{name}}, where @var{name} is an array, removes the
+entire array. A subscript of @samp{*} or @samp{@@} also removes the
+entire array.
+
+The @code{declare}, @code{local}, and @code{readonly}
+builtins each accept a @option{-a} option to specify an indexed
+array and a @option{-A} option to specify an associative array.
+If both options are supplied, @option{-A} takes precedence.
+The @code{read} builtin accepts a @option{-a}
+option to assign a list of words read from the standard input
+to an array, and can read values from the standard input into
+individual array elements. The @code{set} and @code{declare}
+builtins display array values in a way that allows them to be
+reused as input.
+
+@node The Directory Stack
+@section The Directory Stack
+@cindex directory stack
+
+@menu
+* Directory Stack Builtins:: Bash builtin commands to manipulate
+ the directory stack.
+@end menu
+
+The directory stack is a list of recently-visited directories. The
+@code{pushd} builtin adds directories to the stack as it changes
+the current directory, and the @code{popd} builtin removes specified
+directories from the stack and changes the current directory to
+the directory removed. The @code{dirs} builtin displays the contents
+of the directory stack.
+
+The contents of the directory stack are also visible
+as the value of the @env{DIRSTACK} shell variable.
+
+@node Directory Stack Builtins
+@subsection Directory Stack Builtins
+
+@table @code
+
+@item dirs
+@btindex dirs
+@example
+dirs [-clpv] [+@var{N} | -@var{N}]
+@end example
+
+Display the list of currently remembered directories. Directories
+are added to the list with the @code{pushd} command; the
+@code{popd} command removes directories from the list.
+
+@table @code
+@item -c
+Clears the directory stack by deleting all of the elements.
+@item -l
+Produces a listing using full pathnames;
+the default listing format uses a tilde to denote the home directory.
+@item -p
+Causes @code{dirs} to print the directory stack with one entry per
+line.
+@item -v
+Causes @code{dirs} to print the directory stack with one entry per
+line, prefixing each entry with its index in the stack.
+@item +@var{N}
+Displays the @var{N}th directory (counting from the left of the
+list printed by @code{dirs} when invoked without options), starting
+with zero.
+@item -@var{N}
+Displays the @var{N}th directory (counting from the right of the
+list printed by @code{dirs} when invoked without options), starting
+with zero.
+@end table
+
+@item popd
+@btindex popd
+@example
+popd [-n] [+@var{N} | -@var{N}]
+@end example
+
+Remove the top entry from the directory stack, and @code{cd}
+to the new top directory.
+When no arguments are given, @code{popd}
+removes the top directory from the stack and
+performs a @code{cd} to the new top directory. The
+elements are numbered from 0 starting at the first directory listed with
+@code{dirs}; that is, @code{popd} is equivalent to @code{popd +0}.
+
+@table @code
+@item -n
+Suppresses the normal change of directory when removing directories
+from the stack, so that only the stack is manipulated.
+@item +@var{N}
+Removes the @var{N}th directory (counting from the left of the
+list printed by @code{dirs}), starting with zero.
+@item -@var{N}
+Removes the @var{N}th directory (counting from the right of the
+list printed by @code{dirs}), starting with zero.
+@end table
+
+@btindex pushd
+@item pushd
+@example
+pushd [-n] [@var{+N} | @var{-N} | @var{dir}]
+@end example
+
+Save the current directory on the top of the directory stack
+and then @code{cd} to @var{dir}.
+With no arguments, @code{pushd} exchanges the top two directories.
+
+@table @code
+@item -n
+Suppresses the normal change of directory when adding directories
+to the stack, so that only the stack is manipulated.
+@item +@var{N}
+Brings the @var{N}th directory (counting from the left of the
+list printed by @code{dirs}, starting with zero) to the top of
+the list by rotating the stack.
+@item -@var{N}
+Brings the @var{N}th directory (counting from the right of the
+list printed by @code{dirs}, starting with zero) to the top of
+the list by rotating the stack.
+@item @var{dir}
+Makes the current working directory be the top of the stack, making
+it the new current directory as if it had been supplied as an argument
+to the @code{cd} builtin.
+@end table
+@end table
+
+@node Controlling the Prompt
+@section Controlling the Prompt
+@cindex prompting
+
+The value of the variable @env{PROMPT_COMMAND} is examined just before
+Bash prints each primary prompt. If @env{PROMPT_COMMAND} is set and
+has a non-null value, then the
+value is executed just as if it had been typed on the command line.
+
+In addition, the following table describes the special characters which
+can appear in the prompt variables @env{PS1} to @env{PS4}:
+
+@table @code
+@item \a
+A bell character.
+@item \d
+The date, in "Weekday Month Date" format (e.g., "Tue May 26").
+@item \D@{@var{format}@}
+The @var{format} is passed to @code{strftime}(3) and the result is inserted
+into the prompt string; an empty @var{format} results in a locale-specific
+time representation. The braces are required.
+@item \e
+An escape character.
+@item \h
+The hostname, up to the first `.'.
+@item \H
+The hostname.
+@item \j
+The number of jobs currently managed by the shell.
+@item \l
+The basename of the shell's terminal device name.
+@item \n
+A newline.
+@item \r
+A carriage return.
+@item \s
+The name of the shell, the basename of @code{$0} (the portion
+following the final slash).
+@item \t
+The time, in 24-hour HH:MM:SS format.
+@item \T
+The time, in 12-hour HH:MM:SS format.
+@item \@@
+The time, in 12-hour am/pm format.
+@item \A
+The time, in 24-hour HH:MM format.
+@item \u
+The username of the current user.
+@item \v
+The version of Bash (e.g., 2.00)
+@item \V
+The release of Bash, version + patchlevel (e.g., 2.00.0)
+@item \w
+The current working directory, with @env{$HOME} abbreviated with a tilde
+(uses the @env{$PROMPT_DIRTRIM} variable).
+@item \W
+The basename of @env{$PWD}, with @env{$HOME} abbreviated with a tilde.
+@item \!
+The history number of this command.
+@item \#
+The command number of this command.
+@item \$
+If the effective uid is 0, @code{#}, otherwise @code{$}.
+@item \@var{nnn}
+The character whose ASCII code is the octal value @var{nnn}.
+@item \\
+A backslash.
+@item \[
+Begin a sequence of non-printing characters. This could be used to
+embed a terminal control sequence into the prompt.
+@item \]
+End a sequence of non-printing characters.
+@end table
+
+The command number and the history number are usually different:
+the history number of a command is its position in the history
+list, which may include commands restored from the history file
+(@pxref{Bash History Facilities}), while the command number is
+the position in the sequence of commands executed during the current
+shell session.
+
+After the string is decoded, it is expanded via
+parameter expansion, command substitution, arithmetic
+expansion, and quote removal, subject to the value of the
+@code{promptvars} shell option (@pxref{Bash Builtins}).
+
+@node The Restricted Shell
+@section The Restricted Shell
+@cindex restricted shell
+
+If Bash is started with the name @code{rbash}, or the
+@option{--restricted}
+or
+@option{-r}
+option is supplied at invocation, the shell becomes restricted.
+A restricted shell is used to
+set up an environment more controlled than the standard shell.
+A restricted shell behaves identically to @code{bash}
+with the exception that the following are disallowed or not performed:
+
+@itemize @bullet
+@item
+Changing directories with the @code{cd} builtin.
+@item
+Setting or unsetting the values of the @env{SHELL}, @env{PATH},
+@env{ENV}, or @env{BASH_ENV} variables.
+@item
+Specifying command names containing slashes.
+@item
+Specifying a filename containing a slash as an argument to the @code{.}
+builtin command.
+@item
+Specifying a filename containing a slash as an argument to the @option{-p}
+option to the @code{hash} builtin command.
+@item
+Importing function definitions from the shell environment at startup.
+@item
+Parsing the value of @env{SHELLOPTS} from the shell environment at startup.
+@item
+Redirecting output using the @samp{>}, @samp{>|}, @samp{<>}, @samp{>&},
+@samp{&>}, and @samp{>>} redirection operators.
+@item
+Using the @code{exec} builtin to replace the shell with another command.
+@item
+Adding or deleting builtin commands with the
+@option{-f} and @option{-d} options to the @code{enable} builtin.
+@item
+Using the @code{enable} builtin command to enable disabled shell builtins.
+@item
+Specifying the @option{-p} option to the @code{command} builtin.
+@item
+Turning off restricted mode with @samp{set +r} or @samp{set +o restricted}.
+@end itemize
+
+These restrictions are enforced after any startup files are read.
+
+When a command that is found to be a shell script is executed
+(@pxref{Shell Scripts}), @code{rbash} turns off any restrictions in
+the shell spawned to execute the script.
+
+@node Bash POSIX Mode
+@section Bash POSIX Mode
+@cindex POSIX Mode
+
+Starting Bash with the @option{--posix} command-line option or executing
+@samp{set -o posix} while Bash is running will cause Bash to conform more
+closely to the @sc{posix} standard by changing the behavior to
+match that specified by @sc{posix} in areas where the Bash default differs.
+
+When invoked as @code{sh}, Bash enters @sc{posix} mode after reading the
+startup files.
+
+The following list is what's changed when `@sc{posix} mode' is in effect:
+
+@enumerate
+@item
+When a command in the hash table no longer exists, Bash will re-search
+@env{$PATH} to find the new location. This is also available with
+@samp{shopt -s checkhash}.
+
+@item
+The message printed by the job control code and builtins when a job
+exits with a non-zero status is `Done(status)'.
+
+@item
+The message printed by the job control code and builtins when a job
+is stopped is `Stopped(@var{signame})', where @var{signame} is, for
+example, @code{SIGTSTP}.
+
+@item
+The @code{bg} builtin uses the required format to describe each job placed
+in the background, which does not include an indication of whether the job
+is the current or previous job.
+
+@item
+Reserved words appearing in a context where reserved words are recognized
+do not undergo alias expansion.
+
+@item
+The @sc{posix} @env{PS1} and @env{PS2} expansions of @samp{!} to
+the history number and @samp{!!} to @samp{!} are enabled,
+and parameter expansion is performed on the values of @env{PS1} and
+@env{PS2} regardless of the setting of the @code{promptvars} option.
+
+@item
+The @sc{posix} startup files are executed (@env{$ENV}) rather than
+the normal Bash files.
+
+@item
+Tilde expansion is only performed on assignments preceding a command
+name, rather than on all assignment statements on the line.
+
+@item
+The @code{command} builtin does not prevent builtins that take assignment
+statements as arguments from expanding them as assignment statements;
+when not in @sc{posix} mode, assignment builtins lose their assignment
+statement expansion properties when preceded by @code{command}.
+
+@item
+The default history file is @file{~/.sh_history} (this is the
+default value of @env{$HISTFILE}).
+
+@item
+The output of @samp{kill -l} prints all the signal names on a single line,
+separated by spaces, without the @samp{SIG} prefix.
+
+@item
+The @code{kill} builtin does not accept signal names with a @samp{SIG}
+prefix.
+
+@item
+Non-interactive shells exit if @var{filename} in @code{.} @var{filename}
+is not found.
+
+@item
+Non-interactive shells exit if a syntax error in an arithmetic expansion
+results in an invalid expression.
+
+@item
+Non-interactive shells exit if there is a syntax error in a script read
+with the @code{.} or @code{source} builtins, or in a string processed by
+the @code{eval} builtin.
+
+@item
+Redirection operators do not perform filename expansion on the word
+in the redirection unless the shell is interactive.
+
+@item
+Redirection operators do not perform word splitting on the word in the
+redirection.
+
+@item
+Function names must be valid shell @code{name}s. That is, they may not
+contain characters other than letters, digits, and underscores, and
+may not start with a digit. Declaring a function with an invalid name
+causes a fatal syntax error in non-interactive shells.
+
+@item
+Function names may not be the same as one of the @sc{posix} special
+builtins.
+
+@item
+@sc{posix} special builtins are found before shell functions
+during command lookup.
+
+@item
+Literal tildes that appear as the first character in elements of
+the @env{PATH} variable are not expanded as described above
+under @ref{Tilde Expansion}.
+
+@item
+The @code{time} reserved word may be used by itself as a command. When
+used in this way, it displays timing statistics for the shell and its
+completed children. The @env{TIMEFORMAT} variable controls the format
+of the timing information.
+
+@item
+When parsing and expanding a $@{@dots{}@} expansion that appears within
+double quotes, single quotes are no longer special and cannot be used to
+quote a closing brace or other special character, unless the operator is
+one of those defined to perform pattern removal. In this case, they do
+not have to appear as matched pairs.
+
+@item
+The parser does not recognize @code{time} as a reserved word if the next
+token begins with a @samp{-}.
+
+@item
+If a @sc{posix} special builtin returns an error status, a
+non-interactive shell exits. The fatal errors are those listed in
+the @sc{posix} standard, and include things like passing incorrect options,
+redirection errors, variable assignment errors for assignments preceding
+the command name, and so on.
+
+@item
+A non-interactive shell exits with an error status if a variable
+assignment error occurs when no command name follows the assignment
+statements.
+A variable assignment error occurs, for example, when trying to assign
+a value to a readonly variable.
+
+@item
+A non-interactive shell exits with an error status if a variable
+assignment error occurs in an assignment statement preceding a special
+builtin, but not with any other simple command.
+
+@item
+A non-interactive shell exits with an error status if the iteration
+variable in a @code{for} statement or the selection variable in a
+@code{select} statement is a readonly variable.
+
+@item
+Process substitution is not available.
+
+@item
+While variable indirection is available, it may not be applied to the
+@samp{#} and @samp{?} special parameters.
+
+@item
+Assignment statements preceding @sc{posix} special builtins
+persist in the shell environment after the builtin completes.
+
+@item
+Assignment statements preceding shell function calls persist in the
+shell environment after the function returns, as if a @sc{posix}
+special builtin command had been executed.
+
+@item
+The @code{export} and @code{readonly} builtin commands display their
+output in the format required by @sc{posix}.
+
+@item
+The @code{trap} builtin displays signal names without the leading
+@code{SIG}.
+
+@item
+The @code{trap} builtin doesn't check the first argument for a possible
+signal specification and revert the signal handling to the original
+disposition if it is, unless that argument consists solely of digits and
+is a valid signal number. If users want to reset the handler for a given
+signal to the original disposition, they should use @samp{-} as the
+first argument.
+
+@item
+The @code{.} and @code{source} builtins do not search the current directory
+for the filename argument if it is not found by searching @env{PATH}.
+
+@item
+Subshells spawned to execute command substitutions inherit the value of
+the @option{-e} option from the parent shell. When not in @sc{posix} mode,
+Bash clears the @option{-e} option in such subshells.
+
+@item
+Alias expansion is always enabled, even in non-interactive shells.
+
+@item
+When the @code{alias} builtin displays alias definitions, it does not
+display them with a leading @samp{alias } unless the @option{-p} option
+is supplied.
+
+@item
+When the @code{set} builtin is invoked without options, it does not display
+shell function names and definitions.
+
+@item
+When the @code{set} builtin is invoked without options, it displays
+variable values without quotes, unless they contain shell metacharacters,
+even if the result contains nonprinting characters.
+
+@item
+When the @code{cd} builtin is invoked in @var{logical} mode, and the pathname
+constructed from @code{$PWD} and the directory name supplied as an argument
+does not refer to an existing directory, @code{cd} will fail instead of
+falling back to @var{physical} mode.
+
+@item
+The @code{pwd} builtin verifies that the value it prints is the same as the
+current directory, even if it is not asked to check the file system with the
+@option{-P} option.
+
+@item
+When listing the history, the @code{fc} builtin does not include an
+indication of whether or not a history entry has been modified.
+
+@item
+The default editor used by @code{fc} is @code{ed}.
+
+@item
+The @code{type} and @code{command} builtins will not report a non-executable
+file as having been found, though the shell will attempt to execute such a
+file if it is the only so-named file found in @code{$PATH}.
+
+@item
+The @code{vi} editing mode will invoke the @code{vi} editor directly when
+the @samp{v} command is run, instead of checking @code{$VISUAL} and
+@code{$EDITOR}.
+
+@item
+When the @code{xpg_echo} option is enabled, Bash does not attempt to interpret
+any arguments to @code{echo} as options. Each argument is displayed, after
+escape characters are converted.
+
+@item
+The @code{ulimit} builtin uses a block size of 512 bytes for the @option{-c}
+and @option{-f} options.
+
+@item
+The arrival of @code{SIGCHLD} when a trap is set on @code{SIGCHLD} does
+not interrupt the @code{wait} builtin and cause it to return immediately.
+The trap command is run once for each child that exits.
+
+@item
+The @code{read} builtin may be interrupted by a signal for which a trap
+has been set.
+If Bash receives a trapped signal while executing @code{read}, the trap
+handler executes and @code{read} returns an exit status greater than 128.
+
+@end enumerate
+
+There is other @sc{posix} behavior that Bash does not implement by
+default even when in @sc{posix} mode.
+Specifically:
+
+@enumerate
+
+@item
+The @code{fc} builtin checks @code{$EDITOR} as a program to edit history
+entries if @code{FCEDIT} is unset, rather than defaulting directly to
+@code{ed}. @code{fc} uses @code{ed} if @code{EDITOR} is unset.
+
+@item
+As noted above, Bash requires the @code{xpg_echo} option to be enabled for
+the @code{echo} builtin to be fully conformant.
+
+@end enumerate
+
+Bash can be configured to be @sc{posix}-conformant by default, by specifying
+the @option{--enable-strict-posix-default} to @code{configure} when building
+(@pxref{Optional Features}).
+
+@node Job Control
+@chapter Job Control
+
+This chapter discusses what job control is, how it works, and how
+Bash allows you to access its facilities.
+
+@menu
+* Job Control Basics:: How job control works.
+* Job Control Builtins:: Bash builtin commands used to interact
+ with job control.
+* Job Control Variables:: Variables Bash uses to customize job
+ control.
+@end menu
+
+@node Job Control Basics
+@section Job Control Basics
+@cindex job control
+@cindex foreground
+@cindex background
+@cindex suspending jobs
+
+Job control
+refers to the ability to selectively stop (suspend)
+the execution of processes and continue (resume)
+their execution at a later point. A user typically employs
+this facility via an interactive interface supplied jointly
+by the operating system kernel's terminal driver and Bash.
+
+The shell associates a @var{job} with each pipeline. It keeps a
+table of currently executing jobs, which may be listed with the
+@code{jobs} command. When Bash starts a job
+asynchronously, it prints a line that looks
+like:
+@example
+[1] 25647
+@end example
+@noindent
+indicating that this job is job number 1 and that the process @sc{id}
+of the last process in the pipeline associated with this job is
+25647. All of the processes in a single pipeline are members of
+the same job. Bash uses the @var{job} abstraction as the
+basis for job control.
+
+To facilitate the implementation of the user interface to job
+control, the operating system maintains the notion of a current terminal
+process group @sc{id}. Members of this process group (processes whose
+process group @sc{id} is equal to the current terminal process group
+@sc{id}) receive keyboard-generated signals such as @code{SIGINT}.
+These processes are said to be in the foreground. Background
+processes are those whose process group @sc{id} differs from the
+terminal's; such processes are immune to keyboard-generated
+signals. Only foreground processes are allowed to read from or, if
+the user so specifies with @code{stty tostop}, write to the terminal.
+Background processes which attempt to
+read from (write to when @code{stty tostop} is in effect) the
+terminal are sent a @code{SIGTTIN} (@code{SIGTTOU})
+signal by the kernel's terminal driver,
+which, unless caught, suspends the process.
+
+If the operating system on which Bash is running supports
+job control, Bash contains facilities to use it. Typing the
+@var{suspend} character (typically @samp{^Z}, Control-Z) while a
+process is running causes that process to be stopped and returns
+control to Bash. Typing the @var{delayed suspend} character
+(typically @samp{^Y}, Control-Y) causes the process to be stopped
+when it attempts to read input from the terminal, and control to
+be returned to Bash. The user then manipulates the state of
+this job, using the @code{bg} command to continue it in the
+background, the @code{fg} command to continue it in the
+foreground, or the @code{kill} command to kill it. A @samp{^Z}
+takes effect immediately, and has the additional side effect of
+causing pending output and typeahead to be discarded.
+
+There are a number of ways to refer to a job in the shell. The
+character @samp{%} introduces a job specification (@var{jobspec}).
+
+Job number @code{n} may be referred to as @samp{%n}.
+The symbols @samp{%%} and @samp{%+} refer to the shell's notion of the
+current job, which is the last job stopped while it was in the foreground
+or started in the background.
+A single @samp{%} (with no accompanying job specification) also refers
+to the current job.
+The previous job may be referenced using @samp{%-}.
+If there is only a single job, @samp{%+} and @samp{%-} can both be used
+to refer to that job.
+In output pertaining to jobs (e.g., the output of the @code{jobs}
+command), the current job is always flagged with a @samp{+}, and the
+previous job with a @samp{-}.
+
+A job may also be referred to
+using a prefix of the name used to start it, or using a substring
+that appears in its command line. For example, @samp{%ce} refers
+to a stopped @code{ce} job. Using @samp{%?ce}, on the
+other hand, refers to any job containing the string @samp{ce} in
+its command line. If the prefix or substring matches more than one job,
+Bash reports an error.
+
+Simply naming a job can be used to bring it into the foreground:
+@samp{%1} is a synonym for @samp{fg %1}, bringing job 1 from the
+background into the foreground. Similarly, @samp{%1 &} resumes
+job 1 in the background, equivalent to @samp{bg %1}
+
+The shell learns immediately whenever a job changes state.
+Normally, Bash waits until it is about to print a prompt
+before reporting changes in a job's status so as to not interrupt
+any other output.
+If the @option{-b} option to the @code{set} builtin is enabled,
+Bash reports such changes immediately (@pxref{The Set Builtin}).
+Any trap on @code{SIGCHLD} is executed for each child process
+that exits.
+
+If an attempt to exit Bash is made while jobs are stopped, (or running, if
+the @code{checkjobs} option is enabled -- see @ref{The Shopt Builtin}), the
+shell prints a warning message, and if the @code{checkjobs} option is
+enabled, lists the jobs and their statuses.
+The @code{jobs} command may then be used to inspect their status.
+If a second attempt to exit is made without an intervening command,
+Bash does not print another warning, and any stopped jobs are terminated.
+
+@node Job Control Builtins
+@section Job Control Builtins
+
+@table @code
+
+@item bg
+@btindex bg
+@example
+bg [@var{jobspec} @dots{}]
+@end example
+
+Resume each suspended job @var{jobspec} in the background, as if it
+had been started with @samp{&}.
+If @var{jobspec} is not supplied, the current job is used.
+The return status is zero unless it is run when job control is not
+enabled, or, when run with job control enabled, any
+@var{jobspec} was not found or specifies a job
+that was started without job control.
+
+@item fg
+@btindex fg
+@example
+fg [@var{jobspec}]
+@end example
+
+Resume the job @var{jobspec} in the foreground and make it the current job.
+If @var{jobspec} is not supplied, the current job is used.
+The return status is that of the command placed into the foreground,
+or non-zero if run when job control is disabled or, when run with
+job control enabled, @var{jobspec} does not specify a valid job or
+@var{jobspec} specifies a job that was started without job control.
+
+@item jobs
+@btindex jobs
+@example
+jobs [-lnprs] [@var{jobspec}]
+jobs -x @var{command} [@var{arguments}]
+@end example
+
+The first form lists the active jobs. The options have the
+following meanings:
+
+@table @code
+@item -l
+List process @sc{id}s in addition to the normal information.
+
+@item -n
+Display information only about jobs that have changed status since
+the user was last notified of their status.
+
+@item -p
+List only the process @sc{id} of the job's process group leader.
+
+@item -r
+Display only running jobs.
+
+@item -s
+Display only stopped jobs.
+@end table
+
+If @var{jobspec} is given,
+output is restricted to information about that job.
+If @var{jobspec} is not supplied, the status of all jobs is
+listed.
+
+If the @option{-x} option is supplied, @code{jobs} replaces any
+@var{jobspec} found in @var{command} or @var{arguments} with the
+corresponding process group @sc{id}, and executes @var{command},
+passing it @var{argument}s, returning its exit status.
+
+@item kill
+@btindex kill
+@example
+kill [-s @var{sigspec}] [-n @var{signum}] [-@var{sigspec}] @var{jobspec} or @var{pid}
+kill -l [@var{exit_status}]
+@end example
+
+Send a signal specified by @var{sigspec} or @var{signum} to the process
+named by job specification @var{jobspec} or process @sc{id} @var{pid}.
+@var{sigspec} is either a case-insensitive signal name such as
+@code{SIGINT} (with or without the @code{SIG} prefix)
+or a signal number; @var{signum} is a signal number.
+If @var{sigspec} and @var{signum} are not present, @code{SIGTERM} is used.
+The @option{-l} option lists the signal names.
+If any arguments are supplied when @option{-l} is given, the names of the
+signals corresponding to the arguments are listed, and the return status
+is zero.
+@var{exit_status} is a number specifying a signal number or the exit
+status of a process terminated by a signal.
+The return status is zero if at least one signal was successfully sent,
+or non-zero if an error occurs or an invalid option is encountered.
+
+@item wait
+@btindex wait
+@example
+wait [-n] [@var{jobspec} or @var{pid} @dots{}]
+@end example
+
+Wait until the child process specified by each process @sc{id} @var{pid}
+or job specification @var{jobspec} exits and return the exit status of the
+last command waited for.
+If a job spec is given, all processes in the job are waited for.
+If no arguments are given, all currently active child processes are
+waited for, and the return status is zero.
+If the @option{-n} option is supplied, @code{wait} waits for any job to
+terminate and returns its exit status.
+If neither @var{jobspec} nor @var{pid} specifies an active child process
+of the shell, the return status is 127.
+
+@item disown
+@btindex disown
+@example
+disown [-ar] [-h] [@var{jobspec} @dots{}]
+@end example
+
+Without options, remove each @var{jobspec} from the table of
+active jobs.
+If the @option{-h} option is given, the job is not removed from the table,
+but is marked so that @code{SIGHUP} is not sent to the job if the shell
+receives a @code{SIGHUP}.
+If @var{jobspec} is not present, and neither the @option{-a} nor the
+@option{-r} option is supplied, the current job is used.
+If no @var{jobspec} is supplied, the @option{-a} option means to remove or
+mark all jobs; the @option{-r} option without a @var{jobspec}
+argument restricts operation to running jobs.
+
+@item suspend
+@btindex suspend
+@example
+suspend [-f]
+@end example
+
+Suspend the execution of this shell until it receives a
+@code{SIGCONT} signal.
+A login shell cannot be suspended; the @option{-f}
+option can be used to override this and force the suspension.
+@end table
+
+When job control is not active, the @code{kill} and @code{wait}
+builtins do not accept @var{jobspec} arguments. They must be
+supplied process @sc{id}s.
+
+@node Job Control Variables
+@section Job Control Variables
+
+@vtable @code
+
+@item auto_resume
+This variable controls how the shell interacts with the user and
+job control. If this variable exists then single word simple
+commands without redirections are treated as candidates for resumption
+of an existing job. There is no ambiguity allowed; if there is
+more than one job beginning with the string typed, then
+the most recently accessed job will be selected.
+The name of a stopped job, in this context, is the command line
+used to start it. If this variable is set to the value @samp{exact},
+the string supplied must match the name of a stopped job exactly;
+if set to @samp{substring},
+the string supplied needs to match a substring of the name of a
+stopped job. The @samp{substring} value provides functionality
+analogous to the @samp{%?} job @sc{id} (@pxref{Job Control Basics}).
+If set to any other value, the supplied string must
+be a prefix of a stopped job's name; this provides functionality
+analogous to the @samp{%} job @sc{id}.
+
+@end vtable
+
+@set readline-appendix
+@set history-appendix
+@cindex Readline, how to use
+@include rluser.texi
+@cindex History, how to use
+@include hsuser.texi
+@clear readline-appendix
+@clear history-appendix
+
+@node Installing Bash
+@chapter Installing Bash
+
+This chapter provides basic instructions for installing Bash on
+the various supported platforms. The distribution supports the
+@sc{gnu} operating systems, nearly every version of Unix, and several
+non-Unix systems such as BeOS and Interix.
+Other independent ports exist for
+@sc{ms-dos}, @sc{os/2}, and Windows platforms.
+
+@menu
+* Basic Installation:: Installation instructions.
+* Compilers and Options:: How to set special options for various
+ systems.
+* Compiling For Multiple Architectures:: How to compile Bash for more
+ than one kind of system from
+ the same source tree.
+* Installation Names:: How to set the various paths used by the installation.
+* Specifying the System Type:: How to configure Bash for a particular system.
+* Sharing Defaults:: How to share default configuration values among GNU
+ programs.
+* Operation Controls:: Options recognized by the configuration program.
+* Optional Features:: How to enable and disable optional features when
+ building Bash.
+@end menu
+
+@node Basic Installation
+@section Basic Installation
+@cindex installation
+@cindex configuration
+@cindex Bash installation
+@cindex Bash configuration
+
+These are installation instructions for Bash.
+
+The simplest way to compile Bash is:
+
+@enumerate
+@item
+@code{cd} to the directory containing the source code and type
+@samp{./configure} to configure Bash for your system. If you're
+using @code{csh} on an old version of System V, you might need to
+type @samp{sh ./configure} instead to prevent @code{csh} from trying
+to execute @code{configure} itself.
+
+Running @code{configure} takes some time.
+While running, it prints messages telling which features it is
+checking for.
+
+@item
+Type @samp{make} to compile Bash and build the @code{bashbug} bug
+reporting script.
+
+@item
+Optionally, type @samp{make tests} to run the Bash test suite.
+
+@item
+Type @samp{make install} to install @code{bash} and @code{bashbug}.
+This will also install the manual pages and Info file.
+
+@end enumerate
+
+The @code{configure} shell script attempts to guess correct
+values for various system-dependent variables used during
+compilation. It uses those values to create a @file{Makefile} in
+each directory of the package (the top directory, the
+@file{builtins}, @file{doc}, and @file{support} directories,
+each directory under @file{lib}, and several others). It also creates a
+@file{config.h} file containing system-dependent definitions.
+Finally, it creates a shell script named @code{config.status} that you
+can run in the future to recreate the current configuration, a
+file @file{config.cache} that saves the results of its tests to
+speed up reconfiguring, and a file @file{config.log} containing
+compiler output (useful mainly for debugging @code{configure}).
+If at some point
+@file{config.cache} contains results you don't want to keep, you
+may remove or edit it.
+
+To find out more about the options and arguments that the
+@code{configure} script understands, type
+
+@example
+bash-2.04$ ./configure --help
+@end example
+
+@noindent
+at the Bash prompt in your Bash source directory.
+
+If you need to do unusual things to compile Bash, please
+try to figure out how @code{configure} could check whether or not
+to do them, and mail diffs or instructions to
+@email{bash-maintainers@@gnu.org} so they can be
+considered for the next release.
+
+The file @file{configure.ac} is used to create @code{configure}
+by a program called Autoconf. You only need
+@file{configure.ac} if you want to change it or regenerate
+@code{configure} using a newer version of Autoconf. If
+you do this, make sure you are using Autoconf version 2.50 or
+newer.
+
+You can remove the program binaries and object files from the
+source code directory by typing @samp{make clean}. To also remove the
+files that @code{configure} created (so you can compile Bash for
+a different kind of computer), type @samp{make distclean}.
+
+@node Compilers and Options
+@section Compilers and Options
+
+Some systems require unusual options for compilation or linking
+that the @code{configure} script does not know about. You can
+give @code{configure} initial values for variables by setting
+them in the environment. Using a Bourne-compatible shell, you
+can do that on the command line like this:
+
+@example
+CC=c89 CFLAGS=-O2 LIBS=-lposix ./configure
+@end example
+
+On systems that have the @code{env} program, you can do it like this:
+
+@example
+env CPPFLAGS=-I/usr/local/include LDFLAGS=-s ./configure
+@end example
+
+The configuration process uses GCC to build Bash if it
+is available.
+
+@node Compiling For Multiple Architectures
+@section Compiling For Multiple Architectures
+
+You can compile Bash for more than one kind of computer at the
+same time, by placing the object files for each architecture in their
+own directory. To do this, you must use a version of @code{make} that
+supports the @code{VPATH} variable, such as GNU @code{make}.
+@code{cd} to the
+directory where you want the object files and executables to go and run
+the @code{configure} script from the source directory. You may need to
+supply the @option{--srcdir=PATH} argument to tell @code{configure} where the
+source files are. @code{configure} automatically checks for the
+source code in the directory that @code{configure} is in and in `..'.
+
+If you have to use a @code{make} that does not supports the @code{VPATH}
+variable, you can compile Bash for one architecture at a
+time in the source code directory. After you have installed
+Bash for one architecture, use @samp{make distclean} before
+reconfiguring for another architecture.
+
+Alternatively, if your system supports symbolic links, you can use the
+@file{support/mkclone} script to create a build tree which has
+symbolic links back to each file in the source directory. Here's an
+example that creates a build directory in the current directory from a
+source directory @file{/usr/gnu/src/bash-2.0}:
+
+@example
+bash /usr/gnu/src/bash-2.0/support/mkclone -s /usr/gnu/src/bash-2.0 .
+@end example
+
+@noindent
+The @code{mkclone} script requires Bash, so you must have already built
+Bash for at least one architecture before you can create build
+directories for other architectures.
+
+@node Installation Names
+@section Installation Names
+
+By default, @samp{make install} will install into
+@file{/usr/local/bin}, @file{/usr/local/man}, etc. You can
+specify an installation prefix other than @file{/usr/local} by
+giving @code{configure} the option @option{--prefix=@var{PATH}},
+or by specifying a value for the @code{DESTDIR} @samp{make}
+variable when running @samp{make install}.
+
+You can specify separate installation prefixes for
+architecture-specific files and architecture-independent files.
+If you give @code{configure} the option
+@option{--exec-prefix=@var{PATH}}, @samp{make install} will use
+@var{PATH} as the prefix for installing programs and libraries.
+Documentation and other data files will still use the regular prefix.
+
+@node Specifying the System Type
+@section Specifying the System Type
+
+There may be some features @code{configure} can not figure out
+automatically, but need to determine by the type of host Bash
+will run on. Usually @code{configure} can figure that
+out, but if it prints a message saying it can not guess the host
+type, give it the @option{--host=TYPE} option. @samp{TYPE} can
+either be a short name for the system type, such as @samp{sun4},
+or a canonical name with three fields: @samp{CPU-COMPANY-SYSTEM}
+(e.g., @samp{i386-unknown-freebsd4.2}).
+
+See the file @file{support/config.sub} for the possible
+values of each field.
+
+@node Sharing Defaults
+@section Sharing Defaults
+
+If you want to set default values for @code{configure} scripts to
+share, you can create a site shell script called
+@code{config.site} that gives default values for variables like
+@code{CC}, @code{cache_file}, and @code{prefix}. @code{configure}
+looks for @file{PREFIX/share/config.site} if it exists, then
+@file{PREFIX/etc/config.site} if it exists. Or, you can set the
+@code{CONFIG_SITE} environment variable to the location of the site
+script. A warning: the Bash @code{configure} looks for a site script,
+but not all @code{configure} scripts do.
+
+@node Operation Controls
+@section Operation Controls
+
+@code{configure} recognizes the following options to control how it
+operates.
+
+@table @code
+
+@item --cache-file=@var{file}
+Use and save the results of the tests in
+@var{file} instead of @file{./config.cache}. Set @var{file} to
+@file{/dev/null} to disable caching, for debugging
+@code{configure}.
+
+@item --help
+Print a summary of the options to @code{configure}, and exit.
+
+@item --quiet
+@itemx --silent
+@itemx -q
+Do not print messages saying which checks are being made.
+
+@item --srcdir=@var{dir}
+Look for the Bash source code in directory @var{dir}. Usually
+@code{configure} can determine that directory automatically.
+
+@item --version
+Print the version of Autoconf used to generate the @code{configure}
+script, and exit.
+@end table
+
+@code{configure} also accepts some other, not widely used, boilerplate
+options. @samp{configure --help} prints the complete list.
+
+@node Optional Features
+@section Optional Features
+
+The Bash @code{configure} has a number of @option{--enable-@var{feature}}
+options, where @var{feature} indicates an optional part of Bash.
+There are also several @option{--with-@var{package}} options,
+where @var{package} is something like @samp{bash-malloc} or @samp{purify}.
+To turn off the default use of a package, use
+@option{--without-@var{package}}. To configure Bash without a feature
+that is enabled by default, use @option{--disable-@var{feature}}.
+
+Here is a complete list of the @option{--enable-} and
+@option{--with-} options that the Bash @code{configure} recognizes.
+
+@table @code
+@item --with-afs
+Define if you are using the Andrew File System from Transarc.
+
+@item --with-bash-malloc
+Use the Bash version of
+@code{malloc} in the directory @file{lib/malloc}. This is not the same
+@code{malloc} that appears in @sc{gnu} libc, but an older version
+originally derived from the 4.2 @sc{bsd} @code{malloc}. This @code{malloc}
+is very fast, but wastes some space on each allocation.
+This option is enabled by default.
+The @file{NOTES} file contains a list of systems for
+which this should be turned off, and @code{configure} disables this
+option automatically for a number of systems.
+
+@item --with-curses
+Use the curses library instead of the termcap library. This should
+be supplied if your system has an inadequate or incomplete termcap
+database.
+
+@item --with-gnu-malloc
+A synonym for @code{--with-bash-malloc}.
+
+@item --with-installed-readline[=@var{PREFIX}]
+Define this to make Bash link with a locally-installed version of Readline
+rather than the version in @file{lib/readline}. This works only with
+Readline 5.0 and later versions. If @var{PREFIX} is @code{yes} or not
+supplied, @code{configure} uses the values of the make variables
+@code{includedir} and @code{libdir}, which are subdirectories of @code{prefix}
+by default, to find the installed version of Readline if it is not in
+the standard system include and library directories.
+If @var{PREFIX} is @code{no}, Bash links with the version in
+@file{lib/readline}.
+If @var{PREFIX} is set to any other value, @code{configure} treats it as
+a directory pathname and looks for
+the installed version of Readline in subdirectories of that directory
+(include files in @var{PREFIX}/@code{include} and the library in
+@var{PREFIX}/@code{lib}).
+
+@item --with-purify
+Define this to use the Purify memory allocation checker from Rational
+Software.
+
+@item --enable-minimal-config
+This produces a shell with minimal features, close to the historical
+Bourne shell.
+@end table
+
+There are several @option{--enable-} options that alter how Bash is
+compiled and linked, rather than changing run-time features.
+
+@table @code
+@item --enable-largefile
+Enable support for @uref{http://www.sas.com/standards/large_file/x_open.20Mar96.html,
+large files} if the operating system requires special compiler options
+to build programs which can access large files. This is enabled by
+default, if the operating system provides large file support.
+
+@item --enable-profiling
+This builds a Bash binary that produces profiling information to be
+processed by @code{gprof} each time it is executed.
+
+@item --enable-static-link
+This causes Bash to be linked statically, if @code{gcc} is being used.
+This could be used to build a version to use as root's shell.
+@end table
+
+The @samp{minimal-config} option can be used to disable all of
+the following options, but it is processed first, so individual
+options may be enabled using @samp{enable-@var{feature}}.
+
+All of the following options except for @samp{disabled-builtins},
+@samp{direxpand-default}, and
+@samp{xpg-echo-default} are
+enabled by default, unless the operating system does not provide the
+necessary support.
+
+@table @code
+@item --enable-alias
+Allow alias expansion and include the @code{alias} and @code{unalias}
+builtins (@pxref{Aliases}).
+
+@item --enable-arith-for-command
+Include support for the alternate form of the @code{for} command
+that behaves like the C language @code{for} statement
+(@pxref{Looping Constructs}).
+
+@item --enable-array-variables
+Include support for one-dimensional array shell variables
+(@pxref{Arrays}).
+
+@item --enable-bang-history
+Include support for @code{csh}-like history substitution
+(@pxref{History Interaction}).
+
+@item --enable-brace-expansion
+Include @code{csh}-like brace expansion
+( @code{b@{a,b@}c} @expansion{} @code{bac bbc} ).
+See @ref{Brace Expansion}, for a complete description.
+
+@item --enable-casemod-attributes
+Include support for case-modifying attributes in the @code{declare} builtin
+and assignment statements. Variables with the @var{uppercase} attribute,
+for example, will have their values converted to uppercase upon assignment.
+
+@item --enable-casemod-expansion
+Include support for case-modifying word expansions.
+
+@item --enable-command-timing
+Include support for recognizing @code{time} as a reserved word and for
+displaying timing statistics for the pipeline following @code{time}
+(@pxref{Pipelines}).
+This allows pipelines as well as shell builtins and functions to be timed.
+
+@item --enable-cond-command
+Include support for the @code{[[} conditional command.
+(@pxref{Conditional Constructs}).
+
+@item --enable-cond-regexp
+Include support for matching @sc{posix} regular expressions using the
+@samp{=~} binary operator in the @code{[[} conditional command.
+(@pxref{Conditional Constructs}).
+
+@item --enable-coprocesses
+Include support for coprocesses and the @code{coproc} reserved word
+(@pxref{Pipelines}).
+
+@item --enable-debugger
+Include support for the bash debugger (distributed separately).
+
+@item --enable-direxpand-default
+Cause the @code{direxpand} shell option (@pxref{The Shopt Builtin})
+to be enabled by default when the shell starts.
+It is normally disabled by default.
+
+@item --enable-directory-stack
+Include support for a @code{csh}-like directory stack and the
+@code{pushd}, @code{popd}, and @code{dirs} builtins
+(@pxref{The Directory Stack}).
+
+@item --enable-disabled-builtins
+Allow builtin commands to be invoked via @samp{builtin xxx}
+even after @code{xxx} has been disabled using @samp{enable -n xxx}.
+See @ref{Bash Builtins}, for details of the @code{builtin} and
+@code{enable} builtin commands.
+
+@item --enable-dparen-arithmetic
+Include support for the @code{((@dots{}))} command
+(@pxref{Conditional Constructs}).
+
+@item --enable-extended-glob
+Include support for the extended pattern matching features described
+above under @ref{Pattern Matching}.
+
+@item --enable-extended-glob-default
+Set the default value of the @var{extglob} shell option described
+above under @ref{The Shopt Builtin} to be enabled.
+
+@item --enable-function-import
+Include support for importing function definitions exported by another
+instance of the shell from the environment. This option is enabled by
+default.
+
+@item --enable-glob-asciirange-default
+Set the default value of the @var{globasciiranges} shell option described
+above under @ref{The Shopt Builtin} to be enabled.
+This controls the behavior of character ranges when used in pattern matching
+bracket expressions.
+
+@item --enable-help-builtin
+Include the @code{help} builtin, which displays help on shell builtins and
+variables (@pxref{Bash Builtins}).
+
+@item --enable-history
+Include command history and the @code{fc} and @code{history}
+builtin commands (@pxref{Bash History Facilities}).
+
+@item --enable-job-control
+This enables the job control features (@pxref{Job Control}),
+if the operating system supports them.
+
+@item --enable-multibyte
+This enables support for multibyte characters if the operating
+system provides the necessary support.
+
+@item --enable-net-redirections
+This enables the special handling of filenames of the form
+@code{/dev/tcp/@var{host}/@var{port}} and
+@code{/dev/udp/@var{host}/@var{port}}
+when used in redirections (@pxref{Redirections}).
+
+@item --enable-process-substitution
+This enables process substitution (@pxref{Process Substitution}) if
+the operating system provides the necessary support.
+
+@item --enable-progcomp
+Enable the programmable completion facilities
+(@pxref{Programmable Completion}).
+If Readline is not enabled, this option has no effect.
+
+@item --enable-prompt-string-decoding
+Turn on the interpretation of a number of backslash-escaped characters
+in the @env{$PS1}, @env{$PS2}, @env{$PS3}, and @env{$PS4} prompt
+strings. See @ref{Controlling the Prompt}, for a complete list of prompt
+string escape sequences.
+
+@item --enable-readline
+Include support for command-line editing and history with the Bash
+version of the Readline library (@pxref{Command Line Editing}).
+
+@item --enable-restricted
+Include support for a @dfn{restricted shell}. If this is enabled, Bash,
+when called as @code{rbash}, enters a restricted mode. See
+@ref{The Restricted Shell}, for a description of restricted mode.
+
+@item --enable-select
+Include the @code{select} compound command, which allows the generation of
+simple menus (@pxref{Conditional Constructs}).
+
+@item --enable-separate-helpfiles
+Use external files for the documentation displayed by the @code{help} builtin
+instead of storing the text internally.
+
+@item --enable-single-help-strings
+Store the text displayed by the @code{help} builtin as a single string for
+each help topic. This aids in translating the text to different languages.
+You may need to disable this if your compiler cannot handle very long string
+literals.
+
+@item --enable-strict-posix-default
+Make Bash @sc{posix}-conformant by default (@pxref{Bash POSIX Mode}).
+
+@item --enable-usg-echo-default
+A synonym for @code{--enable-xpg-echo-default}.
+
+@item --enable-xpg-echo-default
+Make the @code{echo} builtin expand backslash-escaped characters by default,
+without requiring the @option{-e} option.
+This sets the default value of the @code{xpg_echo} shell option to @code{on},
+which makes the Bash @code{echo} behave more like the version specified in
+the Single Unix Specification, version 3.
+@xref{Bash Builtins}, for a description of the escape sequences that
+@code{echo} recognizes.
+@end table
+
+The file @file{config-top.h} contains C Preprocessor
+@samp{#define} statements for options which are not settable from
+@code{configure}.
+Some of these are not meant to be changed; beware of the consequences if
+you do.
+Read the comments associated with each definition for more
+information about its effect.
+
+@node Reporting Bugs
+@appendix Reporting Bugs
+
+Please report all bugs you find in Bash.
+But first, you should
+make sure that it really is a bug, and that it appears in the latest
+version of Bash.
+The latest version of Bash is always available for FTP from
+@uref{ftp://ftp.gnu.org/pub/gnu/bash/}.
+
+Once you have determined that a bug actually exists, use the
+@code{bashbug} command to submit a bug report.
+If you have a fix, you are encouraged to mail that as well!
+Suggestions and `philosophical' bug reports may be mailed
+to @email{bug-bash@@gnu.org} or posted to the Usenet
+newsgroup @code{gnu.bash.bug}.
+
+All bug reports should include:
+@itemize @bullet
+@item
+The version number of Bash.
+@item
+The hardware and operating system.
+@item
+The compiler used to compile Bash.
+@item
+A description of the bug behaviour.
+@item
+A short script or `recipe' which exercises the bug and may be used
+to reproduce it.
+@end itemize
+
+@noindent
+@code{bashbug} inserts the first three items automatically into
+the template it provides for filing a bug report.
+
+Please send all reports concerning this manual to
+@email{bug-bash@@gnu.org}.
+
+@node Major Differences From The Bourne Shell
+@appendix Major Differences From The Bourne Shell
+
+Bash implements essentially the same grammar, parameter and
+variable expansion, redirection, and quoting as the Bourne Shell.
+Bash uses the @sc{posix} standard as the specification of
+how these features are to be implemented. There are some
+differences between the traditional Bourne shell and Bash; this
+section quickly details the differences of significance. A
+number of these differences are explained in greater depth in
+previous sections.
+This section uses the version of @code{sh} included in SVR4.2 (the
+last version of the historical Bourne shell) as the baseline reference.
+
+@itemize @bullet
+
+@item
+Bash is @sc{posix}-conformant, even where the @sc{posix} specification
+differs from traditional @code{sh} behavior (@pxref{Bash POSIX Mode}).
+
+@item
+Bash has multi-character invocation options (@pxref{Invoking Bash}).
+
+@item
+Bash has command-line editing (@pxref{Command Line Editing}) and
+the @code{bind} builtin.
+
+@item
+Bash provides a programmable word completion mechanism
+(@pxref{Programmable Completion}), and builtin commands
+@code{complete}, @code{compgen}, and @code{compopt}, to
+manipulate it.
+
+@item
+Bash has command history (@pxref{Bash History Facilities}) and the
+@code{history} and @code{fc} builtins to manipulate it.
+The Bash history list maintains timestamp information and uses the
+value of the @code{HISTTIMEFORMAT} variable to display it.
+
+@item
+Bash implements @code{csh}-like history expansion
+(@pxref{History Interaction}).
+
+@item
+Bash has one-dimensional array variables (@pxref{Arrays}), and the
+appropriate variable expansions and assignment syntax to use them.
+Several of the Bash builtins take options to act on arrays.
+Bash provides a number of built-in array variables.
+
+@item
+The @code{$'@dots{}'} quoting syntax, which expands ANSI-C
+backslash-escaped characters in the text between the single quotes,
+is supported (@pxref{ANSI-C Quoting}).
+
+@item
+Bash supports the @code{$"@dots{}"} quoting syntax to do
+locale-specific translation of the characters between the double
+quotes. The @option{-D}, @option{--dump-strings}, and @option{--dump-po-strings}
+invocation options list the translatable strings found in a script
+(@pxref{Locale Translation}).
+
+@item
+Bash implements the @code{!} keyword to negate the return value of
+a pipeline (@pxref{Pipelines}).
+Very useful when an @code{if} statement needs to act only if a test fails.
+The Bash @samp{-o pipefail} option to @code{set} will cause a pipeline to
+return a failure status if any command fails.
+
+@item
+Bash has the @code{time} reserved word and command timing (@pxref{Pipelines}).
+The display of the timing statistics may be controlled with the
+@env{TIMEFORMAT} variable.
+
+@item
+Bash implements the @code{for (( @var{expr1} ; @var{expr2} ; @var{expr3} ))}
+arithmetic for command, similar to the C language (@pxref{Looping Constructs}).
+
+@item
+Bash includes the @code{select} compound command, which allows the
+generation of simple menus (@pxref{Conditional Constructs}).
+
+@item
+Bash includes the @code{[[} compound command, which makes conditional
+testing part of the shell grammar (@pxref{Conditional Constructs}), including
+optional regular expression matching.
+
+@item
+Bash provides optional case-insensitive matching for the @code{case} and
+@code{[[} constructs.
+
+@item
+Bash includes brace expansion (@pxref{Brace Expansion}) and tilde
+expansion (@pxref{Tilde Expansion}).
+
+@item
+Bash implements command aliases and the @code{alias} and @code{unalias}
+builtins (@pxref{Aliases}).
+
+@item
+Bash provides shell arithmetic, the @code{((} compound command
+(@pxref{Conditional Constructs}),
+and arithmetic expansion (@pxref{Shell Arithmetic}).
+
+@item
+Variables present in the shell's initial environment are automatically
+exported to child processes. The Bourne shell does not normally do
+this unless the variables are explicitly marked using the @code{export}
+command.
+
+@item
+Bash supports the @samp{+=} assignment operator, which appends to the value
+of the variable named on the left hand side.
+
+@item
+Bash includes the @sc{posix} pattern removal @samp{%}, @samp{#}, @samp{%%}
+and @samp{##} expansions to remove leading or trailing substrings from
+variable values (@pxref{Shell Parameter Expansion}).
+
+@item
+The expansion @code{$@{#xx@}}, which returns the length of @code{$@{xx@}},
+is supported (@pxref{Shell Parameter Expansion}).
+
+@item
+The expansion @code{$@{var:}@var{offset}@code{[:}@var{length}@code{]@}},
+which expands to the substring of @code{var}'s value of length
+@var{length}, beginning at @var{offset}, is present
+(@pxref{Shell Parameter Expansion}).
+
+@item
+The expansion
+@code{$@{var/[/]}@var{pattern}@code{[/}@var{replacement}@code{]@}},
+which matches @var{pattern} and replaces it with @var{replacement} in
+the value of @code{var}, is available (@pxref{Shell Parameter Expansion}).
+
+@item
+The expansion @code{$@{!@var{prefix}*@}} expansion, which expands to
+the names of all shell variables whose names begin with @var{prefix},
+is available (@pxref{Shell Parameter Expansion}).
+
+@item
+Bash has @var{indirect} variable expansion using @code{$@{!word@}}
+(@pxref{Shell Parameter Expansion}).
+
+@item
+Bash can expand positional parameters beyond @code{$9} using
+@code{$@{@var{num}@}}.
+
+@item
+The @sc{posix} @code{$()} form of command substitution
+is implemented (@pxref{Command Substitution}),
+and preferred to the Bourne shell's @code{``} (which
+is also implemented for backwards compatibility).
+
+@item
+Bash has process substitution (@pxref{Process Substitution}).
+
+@item
+Bash automatically assigns variables that provide information about the
+current user (@env{UID}, @env{EUID}, and @env{GROUPS}), the current host
+(@env{HOSTTYPE}, @env{OSTYPE}, @env{MACHTYPE}, and @env{HOSTNAME}),
+and the instance of Bash that is running (@env{BASH},
+@env{BASH_VERSION}, and @env{BASH_VERSINFO}). @xref{Bash Variables},
+for details.
+
+@item
+The @env{IFS} variable is used to split only the results of expansion,
+not all words (@pxref{Word Splitting}).
+This closes a longstanding shell security hole.
+
+@item
+The filename expansion bracket expression code uses @samp{!} and @samp{^}
+to negate the set of characters between the brackets.
+The Bourne shell uses only @samp{!}.
+
+@item
+Bash implements the full set of @sc{posix} filename expansion operators,
+including @var{character classes}, @var{equivalence classes}, and
+@var{collating symbols} (@pxref{Filename Expansion}).
+
+@item
+Bash implements extended pattern matching features when the @code{extglob}
+shell option is enabled (@pxref{Pattern Matching}).
+
+@item
+It is possible to have a variable and a function with the same name;
+@code{sh} does not separate the two name spaces.
+
+@item
+Bash functions are permitted to have local variables using the
+@code{local} builtin, and thus useful recursive functions may be written
+(@pxref{Bash Builtins}).
+
+@item
+Variable assignments preceding commands affect only that command, even
+builtins and functions (@pxref{Environment}).
+In @code{sh}, all variable assignments
+preceding commands are global unless the command is executed from the
+file system.
+
+@item
+Bash performs filename expansion on filenames specified as operands
+to input and output redirection operators (@pxref{Redirections}).
+
+@item
+Bash contains the @samp{<>} redirection operator, allowing a file to be
+opened for both reading and writing, and the @samp{&>} redirection
+operator, for directing standard output and standard error to the same
+file (@pxref{Redirections}).
+
+@item
+Bash includes the @samp{<<<} redirection operator, allowing a string to
+be used as the standard input to a command.
+
+@item
+Bash implements the @samp{[n]<&@var{word}} and @samp{[n]>&@var{word}}
+redirection operators, which move one file descriptor to another.
+
+@item
+Bash treats a number of filenames specially when they are
+used in redirection operators (@pxref{Redirections}).
+
+@item
+Bash can open network connections to arbitrary machines and services
+with the redirection operators (@pxref{Redirections}).
+
+@item
+The @code{noclobber} option is available to avoid overwriting existing
+files with output redirection (@pxref{The Set Builtin}).
+The @samp{>|} redirection operator may be used to override @code{noclobber}.
+
+@item
+The Bash @code{cd} and @code{pwd} builtins (@pxref{Bourne Shell Builtins})
+each take @option{-L} and @option{-P} options to switch between logical and
+physical modes.
+
+@item
+Bash allows a function to override a builtin with the same name, and provides
+access to that builtin's functionality within the function via the
+@code{builtin} and @code{command} builtins (@pxref{Bash Builtins}).
+
+@item
+The @code{command} builtin allows selective disabling of functions
+when command lookup is performed (@pxref{Bash Builtins}).
+
+@item
+Individual builtins may be enabled or disabled using the @code{enable}
+builtin (@pxref{Bash Builtins}).
+
+@item
+The Bash @code{exec} builtin takes additional options that allow users
+to control the contents of the environment passed to the executed
+command, and what the zeroth argument to the command is to be
+(@pxref{Bourne Shell Builtins}).
+
+@item
+Shell functions may be exported to children via the environment
+using @code{export -f} (@pxref{Shell Functions}).
+
+@item
+The Bash @code{export}, @code{readonly}, and @code{declare} builtins can
+take a @option{-f} option to act on shell functions, a @option{-p} option to
+display variables with various attributes set in a format that can be
+used as shell input, a @option{-n} option to remove various variable
+attributes, and @samp{name=value} arguments to set variable attributes
+and values simultaneously.
+
+@item
+The Bash @code{hash} builtin allows a name to be associated with
+an arbitrary filename, even when that filename cannot be found by
+searching the @env{$PATH}, using @samp{hash -p}
+(@pxref{Bourne Shell Builtins}).
+
+@item
+Bash includes a @code{help} builtin for quick reference to shell
+facilities (@pxref{Bash Builtins}).
+
+@item
+The @code{printf} builtin is available to display formatted output
+(@pxref{Bash Builtins}).
+
+@item
+The Bash @code{read} builtin (@pxref{Bash Builtins})
+will read a line ending in @samp{\} with
+the @option{-r} option, and will use the @env{REPLY} variable as a
+default if no non-option arguments are supplied.
+The Bash @code{read} builtin
+also accepts a prompt string with the @option{-p} option and will use
+Readline to obtain the line when given the @option{-e} option.
+The @code{read} builtin also has additional options to control input:
+the @option{-s} option will turn off echoing of input characters as
+they are read, the @option{-t} option will allow @code{read} to time out
+if input does not arrive within a specified number of seconds, the
+@option{-n} option will allow reading only a specified number of
+characters rather than a full line, and the @option{-d} option will read
+until a particular character rather than newline.
+
+@item
+The @code{return} builtin may be used to abort execution of scripts
+executed with the @code{.} or @code{source} builtins
+(@pxref{Bourne Shell Builtins}).
+
+@item
+Bash includes the @code{shopt} builtin, for finer control of shell
+optional capabilities (@pxref{The Shopt Builtin}), and allows these options
+to be set and unset at shell invocation (@pxref{Invoking Bash}).
+
+@item
+Bash has much more optional behavior controllable with the @code{set}
+builtin (@pxref{The Set Builtin}).
+
+@item
+The @samp{-x} (@option{xtrace}) option displays commands other than
+simple commands when performing an execution trace
+(@pxref{The Set Builtin}).
+
+@item
+The @code{test} builtin (@pxref{Bourne Shell Builtins})
+is slightly different, as it implements the @sc{posix} algorithm,
+which specifies the behavior based on the number of arguments.
+
+@item
+Bash includes the @code{caller} builtin, which displays the context of
+any active subroutine call (a shell function or a script executed with
+the @code{.} or @code{source} builtins). This supports the bash
+debugger.
+
+@item
+The @code{trap} builtin (@pxref{Bourne Shell Builtins}) allows a
+@code{DEBUG} pseudo-signal specification, similar to @code{EXIT}.
+Commands specified with a @code{DEBUG} trap are executed before every
+simple command, @code{for} command, @code{case} command,
+@code{select} command, every arithmetic @code{for} command, and before
+the first command executes in a shell function.
+The @code{DEBUG} trap is not inherited by shell functions unless the
+function has been given the @code{trace} attribute or the
+@code{functrace} option has been enabled using the @code{shopt} builtin.
+The @code{extdebug} shell option has additional effects on the
+@code{DEBUG} trap.
+
+The @code{trap} builtin (@pxref{Bourne Shell Builtins}) allows an
+@code{ERR} pseudo-signal specification, similar to @code{EXIT} and @code{DEBUG}.
+Commands specified with an @code{ERR} trap are executed after a simple
+command fails, with a few exceptions.
+The @code{ERR} trap is not inherited by shell functions unless the
+@code{-o errtrace} option to the @code{set} builtin is enabled.
+
+The @code{trap} builtin (@pxref{Bourne Shell Builtins}) allows a
+@code{RETURN} pseudo-signal specification, similar to
+@code{EXIT} and @code{DEBUG}.
+Commands specified with an @code{RETURN} trap are executed before
+execution resumes after a shell function or a shell script executed with
+@code{.} or @code{source} returns.
+The @code{RETURN} trap is not inherited by shell functions unless the
+function has been given the @code{trace} attribute or the
+@code{functrace} option has been enabled using the @code{shopt} builtin.
+
+@item
+The Bash @code{type} builtin is more extensive and gives more information
+about the names it finds (@pxref{Bash Builtins}).
+
+@item
+The Bash @code{umask} builtin permits a @option{-p} option to cause
+the output to be displayed in the form of a @code{umask} command
+that may be reused as input (@pxref{Bourne Shell Builtins}).
+
+@item
+Bash implements a @code{csh}-like directory stack, and provides the
+@code{pushd}, @code{popd}, and @code{dirs} builtins to manipulate it
+(@pxref{The Directory Stack}).
+Bash also makes the directory stack visible as the value of the
+@env{DIRSTACK} shell variable.
+
+@item
+Bash interprets special backslash-escaped characters in the prompt
+strings when interactive (@pxref{Controlling the Prompt}).
+
+@item
+The Bash restricted mode is more useful (@pxref{The Restricted Shell});
+the SVR4.2 shell restricted mode is too limited.
+
+@item
+The @code{disown} builtin can remove a job from the internal shell
+job table (@pxref{Job Control Builtins}) or suppress the sending
+of @code{SIGHUP} to a job when the shell exits as the result of a
+@code{SIGHUP}.
+
+@item
+Bash includes a number of features to support a separate debugger for
+shell scripts.
+
+@item
+The SVR4.2 shell has two privilege-related builtins
+(@code{mldmode} and @code{priv}) not present in Bash.
+
+@item
+Bash does not have the @code{stop} or @code{newgrp} builtins.
+
+@item
+Bash does not use the @env{SHACCT} variable or perform shell accounting.
+
+@item
+The SVR4.2 @code{sh} uses a @env{TIMEOUT} variable like Bash uses
+@env{TMOUT}.
+
+@end itemize
+
+@noindent
+More features unique to Bash may be found in @ref{Bash Features}.
+
+
+@appendixsec Implementation Differences From The SVR4.2 Shell
+
+Since Bash is a completely new implementation, it does not suffer from
+many of the limitations of the SVR4.2 shell. For instance:
+
+@itemize @bullet
+
+@item
+Bash does not fork a subshell when redirecting into or out of
+a shell control structure such as an @code{if} or @code{while}
+statement.
+
+@item
+Bash does not allow unbalanced quotes. The SVR4.2 shell will silently
+insert a needed closing quote at @code{EOF} under certain circumstances.
+This can be the cause of some hard-to-find errors.
+
+@item
+The SVR4.2 shell uses a baroque memory management scheme based on
+trapping @code{SIGSEGV}. If the shell is started from a process with
+@code{SIGSEGV} blocked (e.g., by using the @code{system()} C library
+function call), it misbehaves badly.
+
+@item
+In a questionable attempt at security, the SVR4.2 shell,
+when invoked without the @option{-p} option, will alter its real
+and effective @sc{uid} and @sc{gid} if they are less than some
+magic threshold value, commonly 100.
+This can lead to unexpected results.
+
+@item
+The SVR4.2 shell does not allow users to trap @code{SIGSEGV},
+@code{SIGALRM}, or @code{SIGCHLD}.
+
+@item
+The SVR4.2 shell does not allow the @env{IFS}, @env{MAILCHECK},
+@env{PATH}, @env{PS1}, or @env{PS2} variables to be unset.
+
+@item
+The SVR4.2 shell treats @samp{^} as the undocumented equivalent of
+@samp{|}.
+
+@item
+Bash allows multiple option arguments when it is invoked (@code{-x -v});
+the SVR4.2 shell allows only one option argument (@code{-xv}). In
+fact, some versions of the shell dump core if the second argument begins
+with a @samp{-}.
+
+@item
+The SVR4.2 shell exits a script if any builtin fails; Bash exits
+a script only if one of the @sc{posix} special builtins fails, and
+only for certain failures, as enumerated in the @sc{posix} standard.
+
+@item
+The SVR4.2 shell behaves differently when invoked as @code{jsh}
+(it turns on job control).
+@end itemize
+
+@node GNU Free Documentation License
+@appendix GNU Free Documentation License
+
+@include fdl.texi
+
+@node Indexes
+@appendix Indexes
+
+@menu
+* Builtin Index:: Index of Bash builtin commands.
+* Reserved Word Index:: Index of Bash reserved words.
+* Variable Index:: Quick reference helps you find the
+ variable you want.
+* Function Index:: Index of bindable Readline functions.
+* Concept Index:: General index for concepts described in
+ this manual.
+@end menu
+
+@node Builtin Index
+@appendixsec Index of Shell Builtin Commands
+@printindex bt
+
+@node Reserved Word Index
+@appendixsec Index of Shell Reserved Words
+@printindex rw
+
+@node Variable Index
+@appendixsec Parameter and Variable Index
+@printindex vr
+
+@node Function Index
+@appendixsec Function Index
+@printindex fn
+
+@node Concept Index
+@appendixsec Concept Index
+@printindex cp
+
+@bye
Copyright (C) 1988-2014 Free Software Foundation, Inc.
@end ignore
-@set LASTCHANGE Fri Nov 28 18:36:44 EST 2014
+@set LASTCHANGE Sat Dec 20 13:52:20 EST 2014
@set EDITION 4.3
@set VERSION 4.3
-@set UPDATED 28 November 2014
-@set UPDATED-MONTH November 2014
+@set UPDATED 20 December 2014
+@set UPDATED-MONTH December 2014
--- /dev/null
+@ignore
+Copyright (C) 1988-2014 Free Software Foundation, Inc.
+@end ignore
+
+@set LASTCHANGE Fri Nov 28 18:36:44 EST 2014
+
+@set EDITION 4.3
+@set VERSION 4.3
+
+@set UPDATED 28 November 2014
+@set UPDATED-MONTH November 2014
--- /dev/null
+#
+# Simple makefile for the sample loadable builtins
+#
+# Copyright (C) 1996 Free Software Foundation, Inc.
+
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2, or (at your option)
+# any later version.
+
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
+
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111 USA.
+
+# Include some boilerplate Gnu makefile definitions.
+prefix = @prefix@
+
+exec_prefix = @exec_prefix@
+bindir = @bindir@
+libdir = @libdir@
+infodir = @infodir@
+includedir = @includedir@
+
+topdir = @top_srcdir@
+BUILD_DIR = @BUILD_DIR@
+srcdir = @srcdir@
+VPATH = .:@srcdir@
+
+@SET_MAKE@
+CC = @CC@
+RM = rm -f
+
+SHELL = @MAKE_SHELL@
+
+host_os = @host_os@
+host_cpu = @host_cpu@
+host_vendor = @host_vendor@
+
+CFLAGS = @CFLAGS@
+LOCAL_CFLAGS = @LOCAL_CFLAGS@
+DEFS = @DEFS@
+LOCAL_DEFS = @LOCAL_DEFS@
+
+CPPFLAGS = @CPPFLAGS@
+
+BASHINCDIR = ${topdir}/include
+
+LIBBUILD = ${BUILD_DIR}/lib
+
+INTL_LIBSRC = ${topdir}/lib/intl
+INTL_BUILDDIR = ${LIBBUILD}/intl
+INTL_INC = @INTL_INC@
+LIBINTL_H = @LIBINTL_H@
+
+CCFLAGS = $(DEFS) $(LOCAL_DEFS) $(LOCAL_CFLAGS) $(CFLAGS)
+
+#
+# These values are generated for configure by ${topdir}/support/shobj-conf.
+# If your system is not supported by that script, but includes facilities for
+# dynamic loading of shared objects, please update the script and send the
+# changes to bash-maintainers@gnu.org.
+#
+SHOBJ_CC = @SHOBJ_CC@
+SHOBJ_CFLAGS = @SHOBJ_CFLAGS@
+SHOBJ_LD = @SHOBJ_LD@
+SHOBJ_LDFLAGS = @SHOBJ_LDFLAGS@
+SHOBJ_XLDFLAGS = @SHOBJ_XLDFLAGS@
+SHOBJ_LIBS = @SHOBJ_LIBS@
+SHOBJ_STATUS = @SHOBJ_STATUS@
+
+INC = -I. -I.. -I$(topdir) -I$(topdir)/lib -I$(topdir)/builtins \
+ -I$(BASHINCDIR) -I$(BUILD_DIR) -I$(LIBBUILD) \
+ -I$(BUILD_DIR)/builtins $(INTL_INC)
+
+.c.o:
+ $(SHOBJ_CC) $(SHOBJ_CFLAGS) $(CCFLAGS) $(INC) -c -o $@ $<
+
+
+ALLPROG = print truefalse sleep pushd finfo logname basename dirname \
+ tty pathchk tee head mkdir rmdir printenv id whoami \
+ uname sync push ln unlink cut realpath getconf strftime
+OTHERPROG = necho hello cat
+
+all: $(SHOBJ_STATUS)
+
+supported: $(ALLPROG)
+others: $(OTHERPROG)
+
+unsupported:
+ @echo "Your system (${host_os}) is not supported by the"
+ @echo "${topdir}/support/shobj-conf script."
+ @echo "If your operating system provides facilities for dynamic"
+ @echo "loading of shared objects using the dlopen(3) interface,"
+ @echo "please update the script and re-run configure.
+ @echo "Please send the changes you made to bash-maintainers@gnu.org"
+ @echo "for inclusion in future bash releases."
+
+everything: supported others
+
+print: print.o
+ $(SHOBJ_LD) $(SHOBJ_LDFLAGS) $(SHOBJ_XLDFLAGS) -o $@ print.o $(SHOBJ_LIBS)
+
+necho: necho.o
+ $(SHOBJ_LD) $(SHOBJ_LDFLAGS) $(SHOBJ_XLDFLAGS) -o $@ necho.o $(SHOBJ_LIBS)
+
+getconf: getconf.o
+ $(SHOBJ_LD) $(SHOBJ_LDFLAGS) $(SHOBJ_XLDFLAGS) -o $@ getconf.o $(SHOBJ_LIBS)
+
+hello: hello.o
+ $(SHOBJ_LD) $(SHOBJ_LDFLAGS) $(SHOBJ_XLDFLAGS) -o $@ hello.o $(SHOBJ_LIBS)
+
+truefalse: truefalse.o
+ $(SHOBJ_LD) $(SHOBJ_LDFLAGS) $(SHOBJ_XLDFLAGS) -o $@ truefalse.o $(SHOBJ_LIBS)
+
+sleep: sleep.o
+ $(SHOBJ_LD) $(SHOBJ_LDFLAGS) $(SHOBJ_XLDFLAGS) -o $@ sleep.o $(SHOBJ_LIBS)
+
+finfo: finfo.o
+ $(SHOBJ_LD) $(SHOBJ_LDFLAGS) $(SHOBJ_XLDFLAGS) -o $@ finfo.o $(SHOBJ_LIBS)
+
+cat: cat.o
+ $(SHOBJ_LD) $(SHOBJ_LDFLAGS) $(SHOBJ_XLDFLAGS) -o $@ cat.o $(SHOBJ_LIBS)
+
+logname: logname.o
+ $(SHOBJ_LD) $(SHOBJ_LDFLAGS) $(SHOBJ_XLDFLAGS) -o $@ logname.o $(SHOBJ_LIBS)
+
+basename: basename.o
+ $(SHOBJ_LD) $(SHOBJ_LDFLAGS) $(SHOBJ_XLDFLAGS) -o $@ basename.o $(SHOBJ_LIBS)
+
+dirname: dirname.o
+ $(SHOBJ_LD) $(SHOBJ_LDFLAGS) $(SHOBJ_XLDFLAGS) -o $@ dirname.o $(SHOBJ_LIBS)
+
+tty: tty.o
+ $(SHOBJ_LD) $(SHOBJ_LDFLAGS) $(SHOBJ_XLDFLAGS) -o $@ tty.o $(SHOBJ_LIBS)
+
+pathchk: pathchk.o
+ $(SHOBJ_LD) $(SHOBJ_LDFLAGS) $(SHOBJ_XLDFLAGS) -o $@ pathchk.o $(SHOBJ_LIBS)
+
+tee: tee.o
+ $(SHOBJ_LD) $(SHOBJ_LDFLAGS) $(SHOBJ_XLDFLAGS) -o $@ tee.o $(SHOBJ_LIBS)
+
+mkdir: mkdir.o
+ $(SHOBJ_LD) $(SHOBJ_LDFLAGS) $(SHOBJ_XLDFLAGS) -o $@ mkdir.o $(SHOBJ_LIBS)
+
+rmdir: rmdir.o
+ $(SHOBJ_LD) $(SHOBJ_LDFLAGS) $(SHOBJ_XLDFLAGS) -o $@ rmdir.o $(SHOBJ_LIBS)
+
+head: head.o
+ $(SHOBJ_LD) $(SHOBJ_LDFLAGS) $(SHOBJ_XLDFLAGS) -o $@ head.o $(SHOBJ_LIBS)
+
+printenv: printenv.o
+ $(SHOBJ_LD) $(SHOBJ_LDFLAGS) $(SHOBJ_XLDFLAGS) -o $@ printenv.o $(SHOBJ_LIBS)
+
+id: id.o
+ $(SHOBJ_LD) $(SHOBJ_LDFLAGS) $(SHOBJ_XLDFLAGS) -o $@ id.o $(SHOBJ_LIBS)
+
+whoami: whoami.o
+ $(SHOBJ_LD) $(SHOBJ_LDFLAGS) $(SHOBJ_XLDFLAGS) -o $@ whoami.o $(SHOBJ_LIBS)
+
+uname: uname.o
+ $(SHOBJ_LD) $(SHOBJ_LDFLAGS) $(SHOBJ_XLDFLAGS) -o $@ uname.o $(SHOBJ_LIBS)
+
+sync: sync.o
+ $(SHOBJ_LD) $(SHOBJ_LDFLAGS) $(SHOBJ_XLDFLAGS) -o $@ sync.o $(SHOBJ_LIBS)
+
+push: push.o
+ $(SHOBJ_LD) $(SHOBJ_LDFLAGS) $(SHOBJ_XLDFLAGS) -o $@ push.o $(SHOBJ_LIBS)
+
+ln: ln.o
+ $(SHOBJ_LD) $(SHOBJ_LDFLAGS) $(SHOBJ_XLDFLAGS) -o $@ ln.o $(SHOBJ_LIBS)
+
+unlink: unlink.o
+ $(SHOBJ_LD) $(SHOBJ_LDFLAGS) $(SHOBJ_XLDFLAGS) -o $@ unlink.o $(SHOBJ_LIBS)
+
+cut: cut.o
+ $(SHOBJ_LD) $(SHOBJ_LDFLAGS) $(SHOBJ_XLDFLAGS) -o $@ cut.o $(SHOBJ_LIBS)
+
+realpath: realpath.o
+ $(SHOBJ_LD) $(SHOBJ_LDFLAGS) $(SHOBJ_XLDFLAGS) -o $@ realpath.o $(SHOBJ_LIBS)
+
+strftime: strftime.o
+ $(SHOBJ_LD) $(SHOBJ_LDFLAGS) $(SHOBJ_XLDFLAGS) -o $@ strftime.o $(SHOBJ_LIBS)
+
+# pushd is a special case. We use the same source that the builtin version
+# uses, with special compilation options.
+#
+pushd.c: ${topdir}/builtins/pushd.def
+ $(RM) $@
+ ${BUILD_DIR}/builtins/mkbuiltins -D ${topdir}/builtins ${topdir}/builtins/pushd.def
+
+pushd.o: pushd.c
+ $(RM) $@
+ $(SHOBJ_CC) -DHAVE_CONFIG_H -DPUSHD_AND_POPD -DLOADABLE_BUILTIN $(SHOBJ_CFLAGS) $(CFLAGS) $(CPPFLAGS) $(INC) -c -o $@ $<
+
+pushd: pushd.o
+ $(SHOBJ_LD) $(SHOBJ_LDFLAGS) $(SHOBJ_XLDFLAGS) -o $@ pushd.o $(SHOBJ_LIBS)
+
+clean:
+ $(RM) $(ALLPROG) $(OTHERPROG) *.o
+ -( cd perl && ${MAKE} ${MFLAGS} $@ )
+
+mostlyclean: clean
+ -( cd perl && ${MAKE} ${MFLAGS} $@ )
+
+distclean maintainer-clean: clean
+ $(RM) Makefile pushd.c
+ -( cd perl && ${MAKE} ${MFLAGS} $@ )
+
+print.o: print.c
+truefalse.o: truefalse.c
+sleep.o: sleep.c
+finfo.o: finfo.c
+logname.o: logname.c
+basename.o: basename.c
+dirname.o: dirname.c
+tty.o: tty.c
+pathchk.o: pathchk.c
+tee.o: tee.c
+head.o: head.c
+rmdir.o: rmdir.c
+necho.o: necho.c
+getconf.o: getconf.c
+hello.o: hello.c
+cat.o: cat.c
+printenv.o: printenv.c
+id.o: id.c
+whoami.o: whoami.c
+uname.o: uname.c
+sync.o: sync.c
+push.o: push.c
+mkdir.o: mkdir.c
+realpath.o: realpath.c
+strftime.o: strftime.c
#endif
if (global)
w->word->flags |= W_ASSNGLOBAL;
- if (integer)
- w->word->flags |= W_ASSIGNINT;
}
#if defined (ARRAY_VARS)
/* Note that we saw an associative array option to a builtin that takes
assignment statements. This is a bit of a kludge. */
- else if (w->word->word[0] == '-' && (strchr (w->word->word+1, 'A') || strchr (w->word->word+1, 'a') || strchr (w->word->word+1, 'g')))
+ else if (w->word->word[0] == '-' && (strpbrk (w->word->word+1, "Aag") != 0))
#else
else if (w->word->word[0] == '-' && strchr (w->word->word+1, 'g'))
#endif
array = 1;
if ((wcmd->word->flags & W_ASSNBLTIN) && strchr (w->word->word+1, 'g'))
global = 1;
- if ((wcmd->word->flags & W_ASSNBLTIN) && strchr (w->word->word+1, 'i'))
- integer = 1;
}
}
--- /dev/null
+/* complete.c -- filename completion for readline. */
+
+/* Copyright (C) 1987-2014 Free Software Foundation, Inc.
+
+ This file is part of the GNU Readline Library (Readline), a library
+ for reading lines of text with interactive input and history editing.
+
+ Readline is free software: you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation, either version 3 of the License, or
+ (at your option) any later version.
+
+ Readline is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with Readline. If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#define READLINE_LIBRARY
+
+#if defined (HAVE_CONFIG_H)
+# include <config.h>
+#endif
+
+#include <sys/types.h>
+#include <fcntl.h>
+#if defined (HAVE_SYS_FILE_H)
+# include <sys/file.h>
+#endif
+
+#include <signal.h>
+
+#if defined (HAVE_UNISTD_H)
+# include <unistd.h>
+#endif /* HAVE_UNISTD_H */
+
+#if defined (HAVE_STDLIB_H)
+# include <stdlib.h>
+#else
+# include "ansi_stdlib.h"
+#endif /* HAVE_STDLIB_H */
+
+#include <stdio.h>
+
+#include <errno.h>
+#if !defined (errno)
+extern int errno;
+#endif /* !errno */
+
+#if defined (HAVE_PWD_H)
+#include <pwd.h>
+#endif
+
+#include "posixdir.h"
+#include "posixstat.h"
+
+/* System-specific feature definitions and include files. */
+#include "rldefs.h"
+#include "rlmbutil.h"
+
+/* Some standard library routines. */
+#include "readline.h"
+#include "xmalloc.h"
+#include "rlprivate.h"
+
+#if defined (COLOR_SUPPORT)
+# include "colors.h"
+#endif
+
+#ifdef __STDC__
+typedef int QSFUNC (const void *, const void *);
+#else
+typedef int QSFUNC ();
+#endif
+
+#ifdef HAVE_LSTAT
+# define LSTAT lstat
+#else
+# define LSTAT stat
+#endif
+
+/* Unix version of a hidden file. Could be different on other systems. */
+#define HIDDEN_FILE(fname) ((fname)[0] == '.')
+
+/* Most systems don't declare getpwent in <pwd.h> if _POSIX_SOURCE is
+ defined. */
+#if defined (HAVE_GETPWENT) && (!defined (HAVE_GETPW_DECLS) || defined (_POSIX_SOURCE))
+extern struct passwd *getpwent PARAMS((void));
+#endif /* HAVE_GETPWENT && (!HAVE_GETPW_DECLS || _POSIX_SOURCE) */
+
+/* If non-zero, then this is the address of a function to call when
+ completing a word would normally display the list of possible matches.
+ This function is called instead of actually doing the display.
+ It takes three arguments: (char **matches, int num_matches, int max_length)
+ where MATCHES is the array of strings that matched, NUM_MATCHES is the
+ number of strings in that array, and MAX_LENGTH is the length of the
+ longest string in that array. */
+rl_compdisp_func_t *rl_completion_display_matches_hook = (rl_compdisp_func_t *)NULL;
+
+#if defined (VISIBLE_STATS) || defined (COLOR_SUPPORT)
+# if !defined (X_OK)
+# define X_OK 1
+# endif
+#endif
+
+#if defined (VISIBLE_STATS)
+static int stat_char PARAMS((char *));
+#endif
+
+#if defined (COLOR_SUPPORT)
+static int colored_stat_start PARAMS((char *));
+static void colored_stat_end PARAMS((void));
+static int colored_prefix_start PARAMS((void));
+static void colored_prefix_end PARAMS((void));
+#endif
+
+static int path_isdir PARAMS((const char *));
+
+static char *rl_quote_filename PARAMS((char *, int, char *));
+
+static void _rl_complete_sigcleanup PARAMS((int, void *));
+
+static void set_completion_defaults PARAMS((int));
+static int get_y_or_n PARAMS((int));
+static int _rl_internal_pager PARAMS((int));
+static char *printable_part PARAMS((char *));
+static int fnwidth PARAMS((const char *));
+static int fnprint PARAMS((const char *, int));
+static int print_filename PARAMS((char *, char *, int));
+
+static char **gen_completion_matches PARAMS((char *, int, int, rl_compentry_func_t *, int, int));
+
+static char **remove_duplicate_matches PARAMS((char **));
+static void insert_match PARAMS((char *, int, int, char *));
+static int append_to_match PARAMS((char *, int, int, int));
+static void insert_all_matches PARAMS((char **, int, char *));
+static int complete_fncmp PARAMS((const char *, int, const char *, int));
+static void display_matches PARAMS((char **));
+static int compute_lcd_of_matches PARAMS((char **, int, const char *));
+static int postprocess_matches PARAMS((char ***, int));
+static int complete_get_screenwidth PARAMS((void));
+
+static char *make_quoted_replacement PARAMS((char *, int, char *));
+
+/* **************************************************************** */
+/* */
+/* Completion matching, from readline's point of view. */
+/* */
+/* **************************************************************** */
+
+/* Variables known only to the readline library. */
+
+/* If non-zero, non-unique completions always show the list of matches. */
+int _rl_complete_show_all = 0;
+
+/* If non-zero, non-unique completions show the list of matches, unless it
+ is not possible to do partial completion and modify the line. */
+int _rl_complete_show_unmodified = 0;
+
+/* If non-zero, completed directory names have a slash appended. */
+int _rl_complete_mark_directories = 1;
+
+/* If non-zero, the symlinked directory completion behavior introduced in
+ readline-4.2a is disabled, and symlinks that point to directories have
+ a slash appended (subject to the value of _rl_complete_mark_directories).
+ This is user-settable via the mark-symlinked-directories variable. */
+int _rl_complete_mark_symlink_dirs = 0;
+
+/* If non-zero, completions are printed horizontally in alphabetical order,
+ like `ls -x'. */
+int _rl_print_completions_horizontally;
+
+/* Non-zero means that case is not significant in filename completion. */
+#if defined (__MSDOS__) && !defined (__DJGPP__)
+int _rl_completion_case_fold = 1;
+#else
+int _rl_completion_case_fold = 0;
+#endif
+
+/* Non-zero means that `-' and `_' are equivalent when comparing filenames
+ for completion. */
+int _rl_completion_case_map = 0;
+
+/* If zero, don't match hidden files (filenames beginning with a `.' on
+ Unix) when doing filename completion. */
+int _rl_match_hidden_files = 1;
+
+/* Length in characters of a common prefix replaced with an ellipsis (`...')
+ when displaying completion matches. Matches whose printable portion has
+ more than this number of displaying characters in common will have the common
+ display prefix replaced with an ellipsis. */
+int _rl_completion_prefix_display_length = 0;
+
+/* The readline-private number of screen columns to use when displaying
+ matches. If < 0 or > _rl_screenwidth, it is ignored. */
+int _rl_completion_columns = -1;
+
+/* Global variables available to applications using readline. */
+
+#if defined (VISIBLE_STATS)
+/* Non-zero means add an additional character to each filename displayed
+ during listing completion iff rl_filename_completion_desired which helps
+ to indicate the type of file being listed. */
+int rl_visible_stats = 0;
+#endif /* VISIBLE_STATS */
+
+#if defined (COLOR_SUPPORT)
+/* Non-zero means to use colors to indicate file type when listing possible
+ completions. The colors used are taken from $LS_COLORS, if set. */
+int _rl_colored_stats = 0;
+
+int _rl_colored_completion_prefix = 1;
+#endif
+
+/* If non-zero, when completing in the middle of a word, don't insert
+ characters from the match that match characters following point in
+ the word. This means, for instance, completing when the cursor is
+ after the `e' in `Makefile' won't result in `Makefilefile'. */
+int _rl_skip_completed_text = 0;
+
+/* If non-zero, menu completion displays the common prefix first in the
+ cycle of possible completions instead of the last. */
+int _rl_menu_complete_prefix_first = 0;
+
+/* If non-zero, then this is the address of a function to call when
+ completing on a directory name. The function is called with
+ the address of a string (the current directory name) as an arg. */
+rl_icppfunc_t *rl_directory_completion_hook = (rl_icppfunc_t *)NULL;
+
+rl_icppfunc_t *rl_directory_rewrite_hook = (rl_icppfunc_t *)NULL;
+
+rl_icppfunc_t *rl_filename_stat_hook = (rl_icppfunc_t *)NULL;
+
+/* If non-zero, this is the address of a function to call when reading
+ directory entries from the filesystem for completion and comparing
+ them to the partial word to be completed. The function should
+ either return its first argument (if no conversion takes place) or
+ newly-allocated memory. This can, for instance, convert filenames
+ between character sets for comparison against what's typed at the
+ keyboard. The returned value is what is added to the list of
+ matches. The second argument is the length of the filename to be
+ converted. */
+rl_dequote_func_t *rl_filename_rewrite_hook = (rl_dequote_func_t *)NULL;
+
+/* Non-zero means readline completion functions perform tilde expansion. */
+int rl_complete_with_tilde_expansion = 0;
+
+/* Pointer to the generator function for completion_matches ().
+ NULL means to use rl_filename_completion_function (), the default filename
+ completer. */
+rl_compentry_func_t *rl_completion_entry_function = (rl_compentry_func_t *)NULL;
+
+/* Pointer to generator function for rl_menu_complete (). NULL means to use
+ *rl_completion_entry_function (see above). */
+rl_compentry_func_t *rl_menu_completion_entry_function = (rl_compentry_func_t *)NULL;
+
+/* Pointer to alternative function to create matches.
+ Function is called with TEXT, START, and END.
+ START and END are indices in RL_LINE_BUFFER saying what the boundaries
+ of TEXT are.
+ If this function exists and returns NULL then call the value of
+ rl_completion_entry_function to try to match, otherwise use the
+ array of strings returned. */
+rl_completion_func_t *rl_attempted_completion_function = (rl_completion_func_t *)NULL;
+
+/* Non-zero means to suppress normal filename completion after the
+ user-specified completion function has been called. */
+int rl_attempted_completion_over = 0;
+
+/* Set to a character indicating the type of completion being performed
+ by rl_complete_internal, available for use by application completion
+ functions. */
+int rl_completion_type = 0;
+
+/* Up to this many items will be displayed in response to a
+ possible-completions call. After that, we ask the user if
+ she is sure she wants to see them all. A negative value means
+ don't ask. */
+int rl_completion_query_items = 100;
+
+int _rl_page_completions = 1;
+
+/* The basic list of characters that signal a break between words for the
+ completer routine. The contents of this variable is what breaks words
+ in the shell, i.e. " \t\n\"\\'`@$><=" */
+const char *rl_basic_word_break_characters = " \t\n\"\\'`@$><=;|&{("; /* }) */
+
+/* List of basic quoting characters. */
+const char *rl_basic_quote_characters = "\"'";
+
+/* The list of characters that signal a break between words for
+ rl_complete_internal. The default list is the contents of
+ rl_basic_word_break_characters. */
+/*const*/ char *rl_completer_word_break_characters = (/*const*/ char *)NULL;
+
+/* Hook function to allow an application to set the completion word
+ break characters before readline breaks up the line. Allows
+ position-dependent word break characters. */
+rl_cpvfunc_t *rl_completion_word_break_hook = (rl_cpvfunc_t *)NULL;
+
+/* List of characters which can be used to quote a substring of the line.
+ Completion occurs on the entire substring, and within the substring
+ rl_completer_word_break_characters are treated as any other character,
+ unless they also appear within this list. */
+const char *rl_completer_quote_characters = (const char *)NULL;
+
+/* List of characters that should be quoted in filenames by the completer. */
+const char *rl_filename_quote_characters = (const char *)NULL;
+
+/* List of characters that are word break characters, but should be left
+ in TEXT when it is passed to the completion function. The shell uses
+ this to help determine what kind of completing to do. */
+const char *rl_special_prefixes = (const char *)NULL;
+
+/* If non-zero, then disallow duplicates in the matches. */
+int rl_ignore_completion_duplicates = 1;
+
+/* Non-zero means that the results of the matches are to be treated
+ as filenames. This is ALWAYS zero on entry, and can only be changed
+ within a completion entry finder function. */
+int rl_filename_completion_desired = 0;
+
+/* Non-zero means that the results of the matches are to be quoted using
+ double quotes (or an application-specific quoting mechanism) if the
+ filename contains any characters in rl_filename_quote_chars. This is
+ ALWAYS non-zero on entry, and can only be changed within a completion
+ entry finder function. */
+int rl_filename_quoting_desired = 1;
+
+/* This function, if defined, is called by the completer when real
+ filename completion is done, after all the matching names have been
+ generated. It is passed a (char**) known as matches in the code below.
+ It consists of a NULL-terminated array of pointers to potential
+ matching strings. The 1st element (matches[0]) is the maximal
+ substring that is common to all matches. This function can re-arrange
+ the list of matches as required, but all elements of the array must be
+ free()'d if they are deleted. The main intent of this function is
+ to implement FIGNORE a la SunOS csh. */
+rl_compignore_func_t *rl_ignore_some_completions_function = (rl_compignore_func_t *)NULL;
+
+/* Set to a function to quote a filename in an application-specific fashion.
+ Called with the text to quote, the type of match found (single or multiple)
+ and a pointer to the quoting character to be used, which the function can
+ reset if desired. */
+rl_quote_func_t *rl_filename_quoting_function = rl_quote_filename;
+
+/* Function to call to remove quoting characters from a filename. Called
+ before completion is attempted, so the embedded quotes do not interfere
+ with matching names in the file system. Readline doesn't do anything
+ with this; it's set only by applications. */
+rl_dequote_func_t *rl_filename_dequoting_function = (rl_dequote_func_t *)NULL;
+
+/* Function to call to decide whether or not a word break character is
+ quoted. If a character is quoted, it does not break words for the
+ completer. */
+rl_linebuf_func_t *rl_char_is_quoted_p = (rl_linebuf_func_t *)NULL;
+
+/* If non-zero, the completion functions don't append anything except a
+ possible closing quote. This is set to 0 by rl_complete_internal and
+ may be changed by an application-specific completion function. */
+int rl_completion_suppress_append = 0;
+
+/* Character appended to completed words when at the end of the line. The
+ default is a space. */
+int rl_completion_append_character = ' ';
+
+/* If non-zero, the completion functions don't append any closing quote.
+ This is set to 0 by rl_complete_internal and may be changed by an
+ application-specific completion function. */
+int rl_completion_suppress_quote = 0;
+
+/* Set to any quote character readline thinks it finds before any application
+ completion function is called. */
+int rl_completion_quote_character;
+
+/* Set to a non-zero value if readline found quoting anywhere in the word to
+ be completed; set before any application completion function is called. */
+int rl_completion_found_quote;
+
+/* If non-zero, a slash will be appended to completed filenames that are
+ symbolic links to directory names, subject to the value of the
+ mark-directories variable (which is user-settable). This exists so
+ that application completion functions can override the user's preference
+ (set via the mark-symlinked-directories variable) if appropriate.
+ It's set to the value of _rl_complete_mark_symlink_dirs in
+ rl_complete_internal before any application-specific completion
+ function is called, so without that function doing anything, the user's
+ preferences are honored. */
+int rl_completion_mark_symlink_dirs;
+
+/* If non-zero, inhibit completion (temporarily). */
+int rl_inhibit_completion;
+
+/* Set to the last key used to invoke one of the completion functions */
+int rl_completion_invoking_key;
+
+/* If non-zero, sort the completion matches. On by default. */
+int rl_sort_completion_matches = 1;
+
+/* Variables local to this file. */
+
+/* Local variable states what happened during the last completion attempt. */
+static int completion_changed_buffer;
+
+/* The result of the query to the user about displaying completion matches */
+static int completion_y_or_n;
+
+static int _rl_complete_display_matches_interrupt = 0;
+
+/*************************************/
+/* */
+/* Bindable completion functions */
+/* */
+/*************************************/
+
+/* Complete the word at or before point. You have supplied the function
+ that does the initial simple matching selection algorithm (see
+ rl_completion_matches ()). The default is to do filename completion. */
+int
+rl_complete (ignore, invoking_key)
+ int ignore, invoking_key;
+{
+ rl_completion_invoking_key = invoking_key;
+
+ if (rl_inhibit_completion)
+ return (_rl_insert_char (ignore, invoking_key));
+ else if (rl_last_func == rl_complete && !completion_changed_buffer)
+ return (rl_complete_internal ('?'));
+ else if (_rl_complete_show_all)
+ return (rl_complete_internal ('!'));
+ else if (_rl_complete_show_unmodified)
+ return (rl_complete_internal ('@'));
+ else
+ return (rl_complete_internal (TAB));
+}
+
+/* List the possible completions. See description of rl_complete (). */
+int
+rl_possible_completions (ignore, invoking_key)
+ int ignore, invoking_key;
+{
+ rl_completion_invoking_key = invoking_key;
+ return (rl_complete_internal ('?'));
+}
+
+int
+rl_insert_completions (ignore, invoking_key)
+ int ignore, invoking_key;
+{
+ rl_completion_invoking_key = invoking_key;
+ return (rl_complete_internal ('*'));
+}
+
+/* Return the correct value to pass to rl_complete_internal performing
+ the same tests as rl_complete. This allows consecutive calls to an
+ application's completion function to list possible completions and for
+ an application-specific completion function to honor the
+ show-all-if-ambiguous readline variable. */
+int
+rl_completion_mode (cfunc)
+ rl_command_func_t *cfunc;
+{
+ if (rl_last_func == cfunc && !completion_changed_buffer)
+ return '?';
+ else if (_rl_complete_show_all)
+ return '!';
+ else if (_rl_complete_show_unmodified)
+ return '@';
+ else
+ return TAB;
+}
+
+/************************************/
+/* */
+/* Completion utility functions */
+/* */
+/************************************/
+
+/* Reset readline state on a signal or other event. */
+void
+_rl_reset_completion_state ()
+{
+ rl_completion_found_quote = 0;
+ rl_completion_quote_character = 0;
+}
+
+static void
+_rl_complete_sigcleanup (sig, ptr)
+ int sig;
+ void *ptr;
+{
+ if (sig == SIGINT) /* XXX - for now */
+ {
+_rl_errmsg("_rl_complete_sigcleanup: ptr = %p", ptr);
+ _rl_free_match_list ((char **)ptr);
+ _rl_complete_display_matches_interrupt = 1;
+ }
+}
+
+/* Set default values for readline word completion. These are the variables
+ that application completion functions can change or inspect. */
+static void
+set_completion_defaults (what_to_do)
+ int what_to_do;
+{
+ /* Only the completion entry function can change these. */
+ rl_filename_completion_desired = 0;
+ rl_filename_quoting_desired = 1;
+ rl_completion_type = what_to_do;
+ rl_completion_suppress_append = rl_completion_suppress_quote = 0;
+ rl_completion_append_character = ' ';
+
+ /* The completion entry function may optionally change this. */
+ rl_completion_mark_symlink_dirs = _rl_complete_mark_symlink_dirs;
+
+ /* Reset private state. */
+ _rl_complete_display_matches_interrupt = 0;
+}
+
+/* The user must press "y" or "n". Non-zero return means "y" pressed. */
+static int
+get_y_or_n (for_pager)
+ int for_pager;
+{
+ int c;
+
+ /* For now, disable pager in callback mode, until we later convert to state
+ driven functions. Have to wait until next major version to add new
+ state definition, since it will change value of RL_STATE_DONE. */
+#if defined (READLINE_CALLBACKS)
+ if (RL_ISSTATE (RL_STATE_CALLBACK))
+ return 1;
+#endif
+
+ for (;;)
+ {
+ RL_SETSTATE(RL_STATE_MOREINPUT);
+ c = rl_read_key ();
+ RL_UNSETSTATE(RL_STATE_MOREINPUT);
+
+ if (c == 'y' || c == 'Y' || c == ' ')
+ return (1);
+ if (c == 'n' || c == 'N' || c == RUBOUT)
+ return (0);
+ if (c == ABORT_CHAR || c < 0)
+{
+_rl_errmsg("get_y_or_n: rl_read_key returns %d", c);
+ _rl_abort_internal ();
+}
+ if (for_pager && (c == NEWLINE || c == RETURN))
+ return (2);
+ if (for_pager && (c == 'q' || c == 'Q'))
+ return (0);
+ rl_ding ();
+ }
+}
+
+static int
+_rl_internal_pager (lines)
+ int lines;
+{
+ int i;
+
+ fprintf (rl_outstream, "--More--");
+ fflush (rl_outstream);
+ i = get_y_or_n (1);
+ _rl_erase_entire_line ();
+ if (i == 0)
+ return -1;
+ else if (i == 2)
+ return (lines - 1);
+ else
+ return 0;
+}
+
+static int
+path_isdir (filename)
+ const char *filename;
+{
+ struct stat finfo;
+
+ return (stat (filename, &finfo) == 0 && S_ISDIR (finfo.st_mode));
+}
+
+#if defined (VISIBLE_STATS)
+/* Return the character which best describes FILENAME.
+ `@' for symbolic links
+ `/' for directories
+ `*' for executables
+ `=' for sockets
+ `|' for FIFOs
+ `%' for character special devices
+ `#' for block special devices */
+static int
+stat_char (filename)
+ char *filename;
+{
+ struct stat finfo;
+ int character, r;
+ char *f;
+ const char *fn;
+
+ /* Short-circuit a //server on cygwin, since that will always behave as
+ a directory. */
+#if __CYGWIN__
+ if (filename[0] == '/' && filename[1] == '/' && strchr (filename+2, '/') == 0)
+ return '/';
+#endif
+
+ f = 0;
+ if (rl_filename_stat_hook)
+ {
+ f = savestring (filename);
+ (*rl_filename_stat_hook) (&f);
+ fn = f;
+ }
+ else
+ fn = filename;
+
+#if defined (HAVE_LSTAT) && defined (S_ISLNK)
+ r = lstat (fn, &finfo);
+#else
+ r = stat (fn, &finfo);
+#endif
+
+ if (r == -1)
+ return (0);
+
+ character = 0;
+ if (S_ISDIR (finfo.st_mode))
+ character = '/';
+#if defined (S_ISCHR)
+ else if (S_ISCHR (finfo.st_mode))
+ character = '%';
+#endif /* S_ISCHR */
+#if defined (S_ISBLK)
+ else if (S_ISBLK (finfo.st_mode))
+ character = '#';
+#endif /* S_ISBLK */
+#if defined (S_ISLNK)
+ else if (S_ISLNK (finfo.st_mode))
+ character = '@';
+#endif /* S_ISLNK */
+#if defined (S_ISSOCK)
+ else if (S_ISSOCK (finfo.st_mode))
+ character = '=';
+#endif /* S_ISSOCK */
+#if defined (S_ISFIFO)
+ else if (S_ISFIFO (finfo.st_mode))
+ character = '|';
+#endif
+ else if (S_ISREG (finfo.st_mode))
+ {
+ if (access (filename, X_OK) == 0)
+ character = '*';
+ }
+
+ xfree (f);
+ return (character);
+}
+#endif /* VISIBLE_STATS */
+
+#if defined (COLOR_SUPPORT)
+static int
+colored_stat_start (filename)
+ char *filename;
+{
+ _rl_set_normal_color ();
+ return (_rl_print_color_indicator (filename));
+}
+
+static void
+colored_stat_end ()
+{
+ _rl_prep_non_filename_text ();
+ _rl_put_indicator (&_rl_color_indicator[C_CLR_TO_EOL]);
+}
+
+static int
+colored_prefix_start ()
+{
+ _rl_set_normal_color ();
+ return (_rl_print_prefix_color ());
+}
+
+static void
+colored_prefix_end ()
+{
+ colored_stat_end (); /* for now */
+}
+#endif
+
+/* Return the portion of PATHNAME that should be output when listing
+ possible completions. If we are hacking filename completion, we
+ are only interested in the basename, the portion following the
+ final slash. Otherwise, we return what we were passed. Since
+ printing empty strings is not very informative, if we're doing
+ filename completion, and the basename is the empty string, we look
+ for the previous slash and return the portion following that. If
+ there's no previous slash, we just return what we were passed. */
+static char *
+printable_part (pathname)
+ char *pathname;
+{
+ char *temp, *x;
+
+ if (rl_filename_completion_desired == 0) /* don't need to do anything */
+ return (pathname);
+
+ temp = strrchr (pathname, '/');
+#if defined (__MSDOS__)
+ if (temp == 0 && ISALPHA ((unsigned char)pathname[0]) && pathname[1] == ':')
+ temp = pathname + 1;
+#endif
+
+ if (temp == 0 || *temp == '\0')
+ return (pathname);
+ /* If the basename is NULL, we might have a pathname like '/usr/src/'.
+ Look for a previous slash and, if one is found, return the portion
+ following that slash. If there's no previous slash, just return the
+ pathname we were passed. */
+ else if (temp[1] == '\0')
+ {
+ for (x = temp - 1; x > pathname; x--)
+ if (*x == '/')
+ break;
+ return ((*x == '/') ? x + 1 : pathname);
+ }
+ else
+ return ++temp;
+}
+
+/* Compute width of STRING when displayed on screen by print_filename */
+static int
+fnwidth (string)
+ const char *string;
+{
+ int width, pos;
+#if defined (HANDLE_MULTIBYTE)
+ mbstate_t ps;
+ int left, w;
+ size_t clen;
+ wchar_t wc;
+
+ left = strlen (string) + 1;
+ memset (&ps, 0, sizeof (mbstate_t));
+#endif
+
+ width = pos = 0;
+ while (string[pos])
+ {
+ if (CTRL_CHAR (string[pos]) || string[pos] == RUBOUT)
+ {
+ width += 2;
+ pos++;
+ }
+ else
+ {
+#if defined (HANDLE_MULTIBYTE)
+ clen = mbrtowc (&wc, string + pos, left - pos, &ps);
+ if (MB_INVALIDCH (clen))
+ {
+ width++;
+ pos++;
+ memset (&ps, 0, sizeof (mbstate_t));
+ }
+ else if (MB_NULLWCH (clen))
+ break;
+ else
+ {
+ pos += clen;
+ w = WCWIDTH (wc);
+ width += (w >= 0) ? w : 1;
+ }
+#else
+ width++;
+ pos++;
+#endif
+ }
+ }
+
+ return width;
+}
+
+#define ELLIPSIS_LEN 3
+
+static int
+fnprint (to_print, prefix_bytes)
+ const char *to_print;
+ int prefix_bytes;
+{
+ int printed_len, w;
+ const char *s;
+ int common_prefix_len;
+#if defined (HANDLE_MULTIBYTE)
+ mbstate_t ps;
+ const char *end;
+ size_t tlen;
+ int width;
+ wchar_t wc;
+
+ end = to_print + strlen (to_print) + 1;
+ memset (&ps, 0, sizeof (mbstate_t));
+#endif
+
+ printed_len = common_prefix_len = 0;
+
+ /* Don't print only the ellipsis if the common prefix is one of the
+ possible completions */
+ if (to_print[prefix_bytes] == '\0')
+ prefix_bytes = 0;
+
+ if (prefix_bytes && _rl_completion_prefix_display_length > 0)
+ {
+ char ellipsis;
+
+ ellipsis = (to_print[prefix_bytes] == '.') ? '_' : '.';
+ for (w = 0; w < ELLIPSIS_LEN; w++)
+ putc (ellipsis, rl_outstream);
+ printed_len = ELLIPSIS_LEN;
+ }
+#if defined (COLOR_SUPPORT)
+ else if (prefix_bytes && _rl_colored_completion_prefix > 0)
+ {
+ common_prefix_len = prefix_bytes;
+ prefix_bytes = 0;
+ /* XXX - print color indicator start here */
+ colored_prefix_start ();
+ }
+#endif
+
+ s = to_print + prefix_bytes;
+ while (*s)
+ {
+ if (CTRL_CHAR (*s))
+ {
+ putc ('^', rl_outstream);
+ putc (UNCTRL (*s), rl_outstream);
+ printed_len += 2;
+ s++;
+#if defined (HANDLE_MULTIBYTE)
+ memset (&ps, 0, sizeof (mbstate_t));
+#endif
+ }
+ else if (*s == RUBOUT)
+ {
+ putc ('^', rl_outstream);
+ putc ('?', rl_outstream);
+ printed_len += 2;
+ s++;
+#if defined (HANDLE_MULTIBYTE)
+ memset (&ps, 0, sizeof (mbstate_t));
+#endif
+ }
+ else
+ {
+#if defined (HANDLE_MULTIBYTE)
+ tlen = mbrtowc (&wc, s, end - s, &ps);
+ if (MB_INVALIDCH (tlen))
+ {
+ tlen = 1;
+ width = 1;
+ memset (&ps, 0, sizeof (mbstate_t));
+ }
+ else if (MB_NULLWCH (tlen))
+ break;
+ else
+ {
+ w = WCWIDTH (wc);
+ width = (w >= 0) ? w : 1;
+ }
+ fwrite (s, 1, tlen, rl_outstream);
+ s += tlen;
+ printed_len += width;
+#else
+ putc (*s, rl_outstream);
+ s++;
+ printed_len++;
+#endif
+ }
+ if (common_prefix_len > 0 && (s - to_print) >= common_prefix_len)
+ {
+ /* printed bytes = s - to_print */
+ /* printed bytes should never be > but check for paranoia's sake */
+ colored_prefix_end ();
+ common_prefix_len = 0;
+ }
+ }
+
+ return printed_len;
+}
+
+/* Output TO_PRINT to rl_outstream. If VISIBLE_STATS is defined and we
+ are using it, check for and output a single character for `special'
+ filenames. Return the number of characters we output. */
+
+static int
+print_filename (to_print, full_pathname, prefix_bytes)
+ char *to_print, *full_pathname;
+ int prefix_bytes;
+{
+ int printed_len, extension_char, slen, tlen;
+ char *s, c, *new_full_pathname, *dn;
+
+ extension_char = 0;
+#if defined (COLOR_SUPPORT)
+ /* Defer printing if we want to prefix with a color indicator */
+ if (_rl_colored_stats == 0 || rl_filename_completion_desired == 0)
+#endif
+ printed_len = fnprint (to_print, prefix_bytes);
+
+ if (rl_filename_completion_desired && (
+#if defined (VISIBLE_STATS)
+ rl_visible_stats ||
+#endif
+#if defined (COLOR_SUPPORT)
+ _rl_colored_stats ||
+#endif
+ _rl_complete_mark_directories))
+ {
+ /* If to_print != full_pathname, to_print is the basename of the
+ path passed. In this case, we try to expand the directory
+ name before checking for the stat character. */
+ if (to_print != full_pathname)
+ {
+ /* Terminate the directory name. */
+ c = to_print[-1];
+ to_print[-1] = '\0';
+
+ /* If setting the last slash in full_pathname to a NUL results in
+ full_pathname being the empty string, we are trying to complete
+ files in the root directory. If we pass a null string to the
+ bash directory completion hook, for example, it will expand it
+ to the current directory. We just want the `/'. */
+ if (full_pathname == 0 || *full_pathname == 0)
+ dn = "/";
+ else if (full_pathname[0] != '/')
+ dn = full_pathname;
+ else if (full_pathname[1] == 0)
+ dn = "//"; /* restore trailing slash to `//' */
+ else if (full_pathname[1] == '/' && full_pathname[2] == 0)
+ dn = "/"; /* don't turn /// into // */
+ else
+ dn = full_pathname;
+ s = tilde_expand (dn);
+ if (rl_directory_completion_hook)
+ (*rl_directory_completion_hook) (&s);
+
+ slen = strlen (s);
+ tlen = strlen (to_print);
+ new_full_pathname = (char *)xmalloc (slen + tlen + 2);
+ strcpy (new_full_pathname, s);
+ if (s[slen - 1] == '/')
+ slen--;
+ else
+ new_full_pathname[slen] = '/';
+ new_full_pathname[slen] = '/';
+ strcpy (new_full_pathname + slen + 1, to_print);
+
+#if defined (VISIBLE_STATS)
+ if (rl_visible_stats)
+ extension_char = stat_char (new_full_pathname);
+ else
+#endif
+ if (_rl_complete_mark_directories)
+ {
+ dn = 0;
+ if (rl_directory_completion_hook == 0 && rl_filename_stat_hook)
+ {
+ dn = savestring (new_full_pathname);
+ (*rl_filename_stat_hook) (&dn);
+ xfree (new_full_pathname);
+ new_full_pathname = dn;
+ }
+ if (path_isdir (new_full_pathname))
+ extension_char = '/';
+ }
+
+#if defined (COLOR_SUPPORT)
+ if (_rl_colored_stats)
+ {
+ colored_stat_start (new_full_pathname);
+ printed_len = fnprint (to_print, prefix_bytes);
+ colored_stat_end ();
+ }
+#endif
+
+ xfree (new_full_pathname);
+ to_print[-1] = c;
+ }
+ else
+ {
+ s = tilde_expand (full_pathname);
+#if defined (VISIBLE_STATS)
+ if (rl_visible_stats)
+ extension_char = stat_char (s);
+ else
+#endif
+ if (_rl_complete_mark_directories && path_isdir (s))
+ extension_char = '/';
+
+#if defined (COLOR_SUPPORT)
+ if (_rl_colored_stats)
+ {
+ colored_stat_start (s);
+ printed_len = fnprint (to_print, prefix_bytes);
+ colored_stat_end ();
+ }
+#endif
+
+ }
+
+ xfree (s);
+ if (extension_char)
+ {
+ putc (extension_char, rl_outstream);
+ printed_len++;
+ }
+ }
+
+ return printed_len;
+}
+
+static char *
+rl_quote_filename (s, rtype, qcp)
+ char *s;
+ int rtype;
+ char *qcp;
+{
+ char *r;
+
+ r = (char *)xmalloc (strlen (s) + 2);
+ *r = *rl_completer_quote_characters;
+ strcpy (r + 1, s);
+ if (qcp)
+ *qcp = *rl_completer_quote_characters;
+ return r;
+}
+
+/* Find the bounds of the current word for completion purposes, and leave
+ rl_point set to the end of the word. This function skips quoted
+ substrings (characters between matched pairs of characters in
+ rl_completer_quote_characters). First we try to find an unclosed
+ quoted substring on which to do matching. If one is not found, we use
+ the word break characters to find the boundaries of the current word.
+ We call an application-specific function to decide whether or not a
+ particular word break character is quoted; if that function returns a
+ non-zero result, the character does not break a word. This function
+ returns the opening quote character if we found an unclosed quoted
+ substring, '\0' otherwise. FP, if non-null, is set to a value saying
+ which (shell-like) quote characters we found (single quote, double
+ quote, or backslash) anywhere in the string. DP, if non-null, is set to
+ the value of the delimiter character that caused a word break. */
+
+char
+_rl_find_completion_word (fp, dp)
+ int *fp, *dp;
+{
+ int scan, end, found_quote, delimiter, pass_next, isbrk;
+ char quote_char, *brkchars;
+
+ end = rl_point;
+ found_quote = delimiter = 0;
+ quote_char = '\0';
+
+ brkchars = 0;
+ if (rl_completion_word_break_hook)
+ brkchars = (*rl_completion_word_break_hook) ();
+ if (brkchars == 0)
+ brkchars = rl_completer_word_break_characters;
+
+ if (rl_completer_quote_characters)
+ {
+ /* We have a list of characters which can be used in pairs to
+ quote substrings for the completer. Try to find the start
+ of an unclosed quoted substring. */
+ /* FOUND_QUOTE is set so we know what kind of quotes we found. */
+ for (scan = pass_next = 0; scan < end; scan = MB_NEXTCHAR (rl_line_buffer, scan, 1, MB_FIND_ANY))
+ {
+ if (pass_next)
+ {
+ pass_next = 0;
+ continue;
+ }
+
+ /* Shell-like semantics for single quotes -- don't allow backslash
+ to quote anything in single quotes, especially not the closing
+ quote. If you don't like this, take out the check on the value
+ of quote_char. */
+ if (quote_char != '\'' && rl_line_buffer[scan] == '\\')
+ {
+ pass_next = 1;
+ found_quote |= RL_QF_BACKSLASH;
+ continue;
+ }
+
+ if (quote_char != '\0')
+ {
+ /* Ignore everything until the matching close quote char. */
+ if (rl_line_buffer[scan] == quote_char)
+ {
+ /* Found matching close. Abandon this substring. */
+ quote_char = '\0';
+ rl_point = end;
+ }
+ }
+ else if (strchr (rl_completer_quote_characters, rl_line_buffer[scan]))
+ {
+ /* Found start of a quoted substring. */
+ quote_char = rl_line_buffer[scan];
+ rl_point = scan + 1;
+ /* Shell-like quoting conventions. */
+ if (quote_char == '\'')
+ found_quote |= RL_QF_SINGLE_QUOTE;
+ else if (quote_char == '"')
+ found_quote |= RL_QF_DOUBLE_QUOTE;
+ else
+ found_quote |= RL_QF_OTHER_QUOTE;
+ }
+ }
+ }
+
+ if (rl_point == end && quote_char == '\0')
+ {
+ /* We didn't find an unclosed quoted substring upon which to do
+ completion, so use the word break characters to find the
+ substring on which to complete. */
+ while (rl_point = MB_PREVCHAR (rl_line_buffer, rl_point, MB_FIND_ANY))
+ {
+ scan = rl_line_buffer[rl_point];
+
+ if (strchr (brkchars, scan) == 0)
+ continue;
+
+ /* Call the application-specific function to tell us whether
+ this word break character is quoted and should be skipped. */
+ if (rl_char_is_quoted_p && found_quote &&
+ (*rl_char_is_quoted_p) (rl_line_buffer, rl_point))
+ continue;
+
+ /* Convoluted code, but it avoids an n^2 algorithm with calls
+ to char_is_quoted. */
+ break;
+ }
+ }
+
+ /* If we are at an unquoted word break, then advance past it. */
+ scan = rl_line_buffer[rl_point];
+
+ /* If there is an application-specific function to say whether or not
+ a character is quoted and we found a quote character, let that
+ function decide whether or not a character is a word break, even
+ if it is found in rl_completer_word_break_characters. Don't bother
+ if we're at the end of the line, though. */
+ if (scan)
+ {
+ if (rl_char_is_quoted_p)
+ isbrk = (found_quote == 0 ||
+ (*rl_char_is_quoted_p) (rl_line_buffer, rl_point) == 0) &&
+ strchr (brkchars, scan) != 0;
+ else
+ isbrk = strchr (brkchars, scan) != 0;
+
+ if (isbrk)
+ {
+ /* If the character that caused the word break was a quoting
+ character, then remember it as the delimiter. */
+ if (rl_basic_quote_characters &&
+ strchr (rl_basic_quote_characters, scan) &&
+ (end - rl_point) > 1)
+ delimiter = scan;
+
+ /* If the character isn't needed to determine something special
+ about what kind of completion to perform, then advance past it. */
+ if (rl_special_prefixes == 0 || strchr (rl_special_prefixes, scan) == 0)
+ rl_point++;
+ }
+ }
+
+ if (fp)
+ *fp = found_quote;
+ if (dp)
+ *dp = delimiter;
+
+ return (quote_char);
+}
+
+static char **
+gen_completion_matches (text, start, end, our_func, found_quote, quote_char)
+ char *text;
+ int start, end;
+ rl_compentry_func_t *our_func;
+ int found_quote, quote_char;
+{
+ char **matches;
+
+ rl_completion_found_quote = found_quote;
+ rl_completion_quote_character = quote_char;
+
+ /* If the user wants to TRY to complete, but then wants to give
+ up and use the default completion function, they set the
+ variable rl_attempted_completion_function. */
+ if (rl_attempted_completion_function)
+ {
+ matches = (*rl_attempted_completion_function) (text, start, end);
+ if (RL_SIG_RECEIVED())
+ {
+ _rl_free_match_list (matches);
+ matches = 0;
+ RL_CHECK_SIGNALS ();
+ }
+
+ if (matches || rl_attempted_completion_over)
+ {
+ rl_attempted_completion_over = 0;
+ return (matches);
+ }
+ }
+
+ /* XXX -- filename dequoting moved into rl_filename_completion_function */
+
+ /* rl_completion_matches will check for signals as well to avoid a long
+ delay while reading a directory. */
+ matches = rl_completion_matches (text, our_func);
+ if (RL_SIG_RECEIVED())
+ {
+ _rl_free_match_list (matches);
+ matches = 0;
+ RL_CHECK_SIGNALS ();
+ }
+ return matches;
+}
+
+/* Filter out duplicates in MATCHES. This frees up the strings in
+ MATCHES. */
+static char **
+remove_duplicate_matches (matches)
+ char **matches;
+{
+ char *lowest_common;
+ int i, j, newlen;
+ char dead_slot;
+ char **temp_array;
+
+ /* Sort the items. */
+ for (i = 0; matches[i]; i++)
+ ;
+
+ /* Sort the array without matches[0], since we need it to
+ stay in place no matter what. */
+ if (i && rl_sort_completion_matches)
+ qsort (matches+1, i-1, sizeof (char *), (QSFUNC *)_rl_qsort_string_compare);
+
+ /* Remember the lowest common denominator for it may be unique. */
+ lowest_common = savestring (matches[0]);
+
+ for (i = newlen = 0; matches[i + 1]; i++)
+ {
+ if (strcmp (matches[i], matches[i + 1]) == 0)
+ {
+ xfree (matches[i]);
+ matches[i] = (char *)&dead_slot;
+ }
+ else
+ newlen++;
+ }
+
+ /* We have marked all the dead slots with (char *)&dead_slot.
+ Copy all the non-dead entries into a new array. */
+ temp_array = (char **)xmalloc ((3 + newlen) * sizeof (char *));
+ for (i = j = 1; matches[i]; i++)
+ {
+ if (matches[i] != (char *)&dead_slot)
+ temp_array[j++] = matches[i];
+ }
+ temp_array[j] = (char *)NULL;
+
+ if (matches[0] != (char *)&dead_slot)
+ xfree (matches[0]);
+
+ /* Place the lowest common denominator back in [0]. */
+ temp_array[0] = lowest_common;
+
+ /* If there is one string left, and it is identical to the
+ lowest common denominator, then the LCD is the string to
+ insert. */
+ if (j == 2 && strcmp (temp_array[0], temp_array[1]) == 0)
+ {
+ xfree (temp_array[1]);
+ temp_array[1] = (char *)NULL;
+ }
+ return (temp_array);
+}
+
+/* Find the common prefix of the list of matches, and put it into
+ matches[0]. */
+static int
+compute_lcd_of_matches (match_list, matches, text)
+ char **match_list;
+ int matches;
+ const char *text;
+{
+ register int i, c1, c2, si;
+ int low; /* Count of max-matched characters. */
+ int lx;
+ char *dtext; /* dequoted TEXT, if needed */
+#if defined (HANDLE_MULTIBYTE)
+ int v;
+ size_t v1, v2;
+ mbstate_t ps1, ps2;
+ wchar_t wc1, wc2;
+#endif
+
+ /* If only one match, just use that. Otherwise, compare each
+ member of the list with the next, finding out where they
+ stop matching. */
+ if (matches == 1)
+ {
+ match_list[0] = match_list[1];
+ match_list[1] = (char *)NULL;
+ return 1;
+ }
+
+ for (i = 1, low = 100000; i < matches; i++)
+ {
+#if defined (HANDLE_MULTIBYTE)
+ if (MB_CUR_MAX > 1 && rl_byte_oriented == 0)
+ {
+ memset (&ps1, 0, sizeof (mbstate_t));
+ memset (&ps2, 0, sizeof (mbstate_t));
+ }
+#endif
+ if (_rl_completion_case_fold)
+ {
+ for (si = 0;
+ (c1 = _rl_to_lower(match_list[i][si])) &&
+ (c2 = _rl_to_lower(match_list[i + 1][si]));
+ si++)
+#if defined (HANDLE_MULTIBYTE)
+ if (MB_CUR_MAX > 1 && rl_byte_oriented == 0)
+ {
+ v1 = mbrtowc(&wc1, match_list[i]+si, strlen (match_list[i]+si), &ps1);
+ v2 = mbrtowc (&wc2, match_list[i+1]+si, strlen (match_list[i+1]+si), &ps2);
+ if (MB_INVALIDCH (v1) || MB_INVALIDCH (v2))
+ {
+ if (c1 != c2) /* do byte comparison */
+ break;
+ continue;
+ }
+ wc1 = towlower (wc1);
+ wc2 = towlower (wc2);
+ if (wc1 != wc2)
+ break;
+ else if (v1 > 1)
+ si += v1 - 1;
+ }
+ else
+#endif
+ if (c1 != c2)
+ break;
+ }
+ else
+ {
+ for (si = 0;
+ (c1 = match_list[i][si]) &&
+ (c2 = match_list[i + 1][si]);
+ si++)
+#if defined (HANDLE_MULTIBYTE)
+ if (MB_CUR_MAX > 1 && rl_byte_oriented == 0)
+ {
+ mbstate_t ps_back;
+ ps_back = ps1;
+ if (!_rl_compare_chars (match_list[i], si, &ps1, match_list[i+1], si, &ps2))
+ break;
+ else if ((v = _rl_get_char_len (&match_list[i][si], &ps_back)) > 1)
+ si += v - 1;
+ }
+ else
+#endif
+ if (c1 != c2)
+ break;
+ }
+
+ if (low > si)
+ low = si;
+ }
+
+ /* If there were multiple matches, but none matched up to even the
+ first character, and the user typed something, use that as the
+ value of matches[0]. */
+ if (low == 0 && text && *text)
+ {
+ match_list[0] = (char *)xmalloc (strlen (text) + 1);
+ strcpy (match_list[0], text);
+ }
+ else
+ {
+ match_list[0] = (char *)xmalloc (low + 1);
+
+ /* XXX - this might need changes in the presence of multibyte chars */
+
+ /* If we are ignoring case, try to preserve the case of the string
+ the user typed in the face of multiple matches differing in case. */
+ if (_rl_completion_case_fold)
+ {
+ /* We're making an assumption here:
+ IF we're completing filenames AND
+ the application has defined a filename dequoting function AND
+ we found a quote character AND
+ the application has requested filename quoting
+ THEN
+ we assume that TEXT was dequoted before checking against
+ the file system and needs to be dequoted here before we
+ check against the list of matches
+ FI */
+ dtext = (char *)NULL;
+ if (rl_filename_completion_desired &&
+ rl_filename_dequoting_function &&
+ rl_completion_found_quote &&
+ rl_filename_quoting_desired)
+ {
+ dtext = (*rl_filename_dequoting_function) ((char *)text, rl_completion_quote_character);
+ text = dtext;
+ }
+
+ /* sort the list to get consistent answers. */
+ qsort (match_list+1, matches, sizeof(char *), (QSFUNC *)_rl_qsort_string_compare);
+
+ si = strlen (text);
+ lx = (si <= low) ? si : low; /* check shorter of text and matches */
+ /* Try to preserve the case of what the user typed in the presence of
+ multiple matches: check each match for something that matches
+ what the user typed taking case into account; use it up to common
+ length of matches if one is found. If not, just use first match. */
+ for (i = 1; i <= matches; i++)
+ if (strncmp (match_list[i], text, lx) == 0)
+ {
+ strncpy (match_list[0], match_list[i], low);
+ break;
+ }
+ /* no casematch, use first entry */
+ if (i > matches)
+ strncpy (match_list[0], match_list[1], low);
+
+ FREE (dtext);
+ }
+ else
+ strncpy (match_list[0], match_list[1], low);
+
+ match_list[0][low] = '\0';
+ }
+
+ return matches;
+}
+
+static int
+postprocess_matches (matchesp, matching_filenames)
+ char ***matchesp;
+ int matching_filenames;
+{
+ char *t, **matches, **temp_matches;
+ int nmatch, i;
+
+ matches = *matchesp;
+
+ if (matches == 0)
+ return 0;
+
+ /* It seems to me that in all the cases we handle we would like
+ to ignore duplicate possibilities. Scan for the text to
+ insert being identical to the other completions. */
+ if (rl_ignore_completion_duplicates)
+ {
+ temp_matches = remove_duplicate_matches (matches);
+ xfree (matches);
+ matches = temp_matches;
+ }
+
+ /* If we are matching filenames, then here is our chance to
+ do clever processing by re-examining the list. Call the
+ ignore function with the array as a parameter. It can
+ munge the array, deleting matches as it desires. */
+ if (rl_ignore_some_completions_function && matching_filenames)
+ {
+ for (nmatch = 1; matches[nmatch]; nmatch++)
+ ;
+ (void)(*rl_ignore_some_completions_function) (matches);
+ if (matches == 0 || matches[0] == 0)
+ {
+ FREE (matches);
+ *matchesp = (char **)0;
+ return 0;
+ }
+ else
+ {
+ /* If we removed some matches, recompute the common prefix. */
+ for (i = 1; matches[i]; i++)
+ ;
+ if (i > 1 && i < nmatch)
+ {
+ t = matches[0];
+ compute_lcd_of_matches (matches, i - 1, t);
+ FREE (t);
+ }
+ }
+ }
+
+ *matchesp = matches;
+ return (1);
+}
+
+static int
+complete_get_screenwidth ()
+{
+ int cols;
+ char *envcols;
+
+ cols = _rl_completion_columns;
+ if (cols >= 0 && cols <= _rl_screenwidth)
+ return cols;
+ envcols = getenv ("COLUMNS");
+ if (envcols && *envcols)
+ cols = atoi (envcols);
+ if (cols >= 0 && cols <= _rl_screenwidth)
+ return cols;
+ return _rl_screenwidth;
+}
+
+/* A convenience function for displaying a list of strings in
+ columnar format on readline's output stream. MATCHES is the list
+ of strings, in argv format, LEN is the number of strings in MATCHES,
+ and MAX is the length of the longest string in MATCHES. */
+void
+rl_display_match_list (matches, len, max)
+ char **matches;
+ int len, max;
+{
+ int count, limit, printed_len, lines, cols;
+ int i, j, k, l, common_length, sind;
+ char *temp, *t;
+
+ /* Find the length of the prefix common to all items: length as displayed
+ characters (common_length) and as a byte index into the matches (sind) */
+ common_length = sind = 0;
+ if (_rl_completion_prefix_display_length > 0)
+ {
+ t = printable_part (matches[0]);
+ temp = strrchr (t, '/'); /* check again in case of /usr/src/ */
+ common_length = temp ? fnwidth (temp) : fnwidth (t);
+ sind = temp ? strlen (temp) : strlen (t);
+
+ if (common_length > _rl_completion_prefix_display_length && common_length > ELLIPSIS_LEN)
+ max -= common_length - ELLIPSIS_LEN;
+ else
+ common_length = sind = 0;
+ }
+#if defined (COLOR_SUPPORT)
+ else if (_rl_colored_completion_prefix > 0)
+ {
+ t = printable_part (matches[0]);
+ temp = strrchr (t, '/');
+ common_length = temp ? fnwidth (temp) : fnwidth (t);
+ sind = temp ? RL_STRLEN (temp+1) : RL_STRLEN (t); /* want portion after final slash */
+ }
+#endif
+
+ /* How many items of MAX length can we fit in the screen window? */
+ cols = complete_get_screenwidth ();
+ max += 2;
+ limit = cols / max;
+ if (limit != 1 && (limit * max == cols))
+ limit--;
+
+ /* If cols == 0, limit will end up -1 */
+ if (cols < _rl_screenwidth && limit < 0)
+ limit = 1;
+
+ /* Avoid a possible floating exception. If max > cols,
+ limit will be 0 and a divide-by-zero fault will result. */
+ if (limit == 0)
+ limit = 1;
+
+ /* How many iterations of the printing loop? */
+ count = (len + (limit - 1)) / limit;
+
+ /* Watch out for special case. If LEN is less than LIMIT, then
+ just do the inner printing loop.
+ 0 < len <= limit implies count = 1. */
+
+ /* Sort the items if they are not already sorted. */
+ if (rl_ignore_completion_duplicates == 0 && rl_sort_completion_matches)
+ qsort (matches + 1, len, sizeof (char *), (QSFUNC *)_rl_qsort_string_compare);
+
+ rl_crlf ();
+
+ lines = 0;
+ if (_rl_print_completions_horizontally == 0)
+ {
+ /* Print the sorted items, up-and-down alphabetically, like ls. */
+ for (i = 1; i <= count; i++)
+ {
+ for (j = 0, l = i; j < limit; j++)
+ {
+ if (l > len || matches[l] == 0)
+ break;
+ else
+ {
+ temp = printable_part (matches[l]);
+ printed_len = print_filename (temp, matches[l], sind);
+
+fflush(rl_outstream);
+usleep(500000);
+ if (j + 1 < limit)
+ for (k = 0; k < max - printed_len; k++)
+ putc (' ', rl_outstream);
+ }
+ l += count;
+ }
+ rl_crlf ();
+ if (RL_SIG_RECEIVED ())
+ return;
+ lines++;
+ if (_rl_page_completions && lines >= (_rl_screenheight - 1) && i < count)
+ {
+ lines = _rl_internal_pager (lines);
+ if (lines < 0)
+ return;
+ }
+ }
+ }
+ else
+ {
+ /* Print the sorted items, across alphabetically, like ls -x. */
+ for (i = 1; matches[i]; i++)
+ {
+ temp = printable_part (matches[i]);
+ printed_len = print_filename (temp, matches[i], sind);
+ /* Have we reached the end of this line? */
+ if (RL_SIG_RECEIVED ())
+ return;
+ if (matches[i+1])
+ {
+ if (limit == 1 || (i && (limit > 1) && (i % limit) == 0))
+ {
+ rl_crlf ();
+ lines++;
+ if (_rl_page_completions && lines >= _rl_screenheight - 1)
+ {
+ lines = _rl_internal_pager (lines);
+ if (lines < 0)
+ return;
+ }
+ }
+ else
+ for (k = 0; k < max - printed_len; k++)
+ putc (' ', rl_outstream);
+ }
+ }
+ rl_crlf ();
+ }
+}
+
+/* Display MATCHES, a list of matching filenames in argv format. This
+ handles the simple case -- a single match -- first. If there is more
+ than one match, we compute the number of strings in the list and the
+ length of the longest string, which will be needed by the display
+ function. If the application wants to handle displaying the list of
+ matches itself, it sets RL_COMPLETION_DISPLAY_MATCHES_HOOK to the
+ address of a function, and we just call it. If we're handling the
+ display ourselves, we just call rl_display_match_list. We also check
+ that the list of matches doesn't exceed the user-settable threshold,
+ and ask the user if he wants to see the list if there are more matches
+ than RL_COMPLETION_QUERY_ITEMS. */
+static void
+display_matches (matches)
+ char **matches;
+{
+ int len, max, i;
+ char *temp;
+
+ /* Move to the last visible line of a possibly-multiple-line command. */
+ _rl_move_vert (_rl_vis_botlin);
+
+ /* Handle simple case first. What if there is only one answer? */
+ if (matches[1] == 0)
+ {
+ temp = printable_part (matches[0]);
+ rl_crlf ();
+ print_filename (temp, matches[0], 0);
+ rl_crlf ();
+
+ rl_forced_update_display ();
+ rl_display_fixed = 1;
+
+ return;
+ }
+
+ /* There is more than one answer. Find out how many there are,
+ and find the maximum printed length of a single entry. */
+ for (max = 0, i = 1; matches[i]; i++)
+ {
+ temp = printable_part (matches[i]);
+ len = fnwidth (temp);
+
+ if (len > max)
+ max = len;
+ }
+
+ len = i - 1;
+
+ /* If the caller has defined a display hook, then call that now. */
+ if (rl_completion_display_matches_hook)
+ {
+ (*rl_completion_display_matches_hook) (matches, len, max);
+ return;
+ }
+
+ /* If there are many items, then ask the user if she really wants to
+ see them all. */
+ if (rl_completion_query_items > 0 && len >= rl_completion_query_items)
+ {
+ rl_crlf ();
+ fprintf (rl_outstream, "Display all %d possibilities? (y or n)", len);
+ fflush (rl_outstream);
+ if ((completion_y_or_n = get_y_or_n (0)) == 0)
+ {
+ rl_crlf ();
+
+ rl_forced_update_display ();
+ rl_display_fixed = 1;
+
+ return;
+ }
+ }
+
+ rl_display_match_list (matches, len, max);
+
+ rl_forced_update_display ();
+ rl_display_fixed = 1;
+}
+
+static char *
+make_quoted_replacement (match, mtype, qc)
+ char *match;
+ int mtype;
+ char *qc; /* Pointer to quoting character, if any */
+{
+ int should_quote, do_replace;
+ char *replacement;
+
+ /* If we are doing completion on quoted substrings, and any matches
+ contain any of the completer_word_break_characters, then auto-
+ matically prepend the substring with a quote character (just pick
+ the first one from the list of such) if it does not already begin
+ with a quote string. FIXME: Need to remove any such automatically
+ inserted quote character when it no longer is necessary, such as
+ if we change the string we are completing on and the new set of
+ matches don't require a quoted substring. */
+ replacement = match;
+
+ should_quote = match && rl_completer_quote_characters &&
+ rl_filename_completion_desired &&
+ rl_filename_quoting_desired;
+
+ if (should_quote)
+ should_quote = should_quote && (!qc || !*qc ||
+ (rl_completer_quote_characters && strchr (rl_completer_quote_characters, *qc)));
+
+ if (should_quote)
+ {
+ /* If there is a single match, see if we need to quote it.
+ This also checks whether the common prefix of several
+ matches needs to be quoted. */
+ should_quote = rl_filename_quote_characters
+ ? (_rl_strpbrk (match, rl_filename_quote_characters) != 0)
+ : 0;
+
+ do_replace = should_quote ? mtype : NO_MATCH;
+ /* Quote the replacement, since we found an embedded
+ word break character in a potential match. */
+ if (do_replace != NO_MATCH && rl_filename_quoting_function)
+ replacement = (*rl_filename_quoting_function) (match, do_replace, qc);
+ }
+ return (replacement);
+}
+
+static void
+insert_match (match, start, mtype, qc)
+ char *match;
+ int start, mtype;
+ char *qc;
+{
+ char *replacement, *r;
+ char oqc;
+ int end, rlen;
+
+ oqc = qc ? *qc : '\0';
+ replacement = make_quoted_replacement (match, mtype, qc);
+
+ /* Now insert the match. */
+ if (replacement)
+ {
+ rlen = strlen (replacement);
+ /* Don't double an opening quote character. */
+ if (qc && *qc && start && rl_line_buffer[start - 1] == *qc &&
+ replacement[0] == *qc)
+ start--;
+ /* If make_quoted_replacement changed the quoting character, remove
+ the opening quote and insert the (fully-quoted) replacement. */
+ else if (qc && (*qc != oqc) && start && rl_line_buffer[start - 1] == oqc &&
+ replacement[0] != oqc)
+ start--;
+ end = rl_point - 1;
+ /* Don't double a closing quote character */
+ if (qc && *qc && end && rl_line_buffer[rl_point] == *qc && replacement[rlen - 1] == *qc)
+ end++;
+ if (_rl_skip_completed_text)
+ {
+ r = replacement;
+ while (start < rl_end && *r && rl_line_buffer[start] == *r)
+ {
+ start++;
+ r++;
+ }
+ if (start <= end || *r)
+ _rl_replace_text (r, start, end);
+ rl_point = start + strlen (r);
+ }
+ else
+ _rl_replace_text (replacement, start, end);
+ if (replacement != match)
+ xfree (replacement);
+ }
+}
+
+/* Append any necessary closing quote and a separator character to the
+ just-inserted match. If the user has specified that directories
+ should be marked by a trailing `/', append one of those instead. The
+ default trailing character is a space. Returns the number of characters
+ appended. If NONTRIVIAL_MATCH is set, we test for a symlink (if the OS
+ has them) and don't add a suffix for a symlink to a directory. A
+ nontrivial match is one that actually adds to the word being completed.
+ The variable rl_completion_mark_symlink_dirs controls this behavior
+ (it's initially set to the what the user has chosen, indicated by the
+ value of _rl_complete_mark_symlink_dirs, but may be modified by an
+ application's completion function). */
+static int
+append_to_match (text, delimiter, quote_char, nontrivial_match)
+ char *text;
+ int delimiter, quote_char, nontrivial_match;
+{
+ char temp_string[4], *filename, *fn;
+ int temp_string_index, s;
+ struct stat finfo;
+
+ temp_string_index = 0;
+ if (quote_char && rl_point && rl_completion_suppress_quote == 0 &&
+ rl_line_buffer[rl_point - 1] != quote_char)
+ temp_string[temp_string_index++] = quote_char;
+
+ if (delimiter)
+ temp_string[temp_string_index++] = delimiter;
+ else if (rl_completion_suppress_append == 0 && rl_completion_append_character)
+ temp_string[temp_string_index++] = rl_completion_append_character;
+
+ temp_string[temp_string_index++] = '\0';
+
+ if (rl_filename_completion_desired)
+ {
+ filename = tilde_expand (text);
+ if (rl_filename_stat_hook)
+ {
+ fn = savestring (filename);
+ (*rl_filename_stat_hook) (&fn);
+ xfree (filename);
+ filename = fn;
+ }
+ s = (nontrivial_match && rl_completion_mark_symlink_dirs == 0)
+ ? LSTAT (filename, &finfo)
+ : stat (filename, &finfo);
+ if (s == 0 && S_ISDIR (finfo.st_mode))
+ {
+ if (_rl_complete_mark_directories /* && rl_completion_suppress_append == 0 */)
+ {
+ /* This is clumsy. Avoid putting in a double slash if point
+ is at the end of the line and the previous character is a
+ slash. */
+ if (rl_point && rl_line_buffer[rl_point] == '\0' && rl_line_buffer[rl_point - 1] == '/')
+ ;
+ else if (rl_line_buffer[rl_point] != '/')
+ rl_insert_text ("/");
+ }
+ }
+#ifdef S_ISLNK
+ /* Don't add anything if the filename is a symlink and resolves to a
+ directory. */
+ else if (s == 0 && S_ISLNK (finfo.st_mode) && path_isdir (filename))
+ ;
+#endif
+ else
+ {
+ if (rl_point == rl_end && temp_string_index)
+ rl_insert_text (temp_string);
+ }
+ xfree (filename);
+ }
+ else
+ {
+ if (rl_point == rl_end && temp_string_index)
+ rl_insert_text (temp_string);
+ }
+
+ return (temp_string_index);
+}
+
+static void
+insert_all_matches (matches, point, qc)
+ char **matches;
+ int point;
+ char *qc;
+{
+ int i;
+ char *rp;
+
+ rl_begin_undo_group ();
+ /* remove any opening quote character; make_quoted_replacement will add
+ it back. */
+ if (qc && *qc && point && rl_line_buffer[point - 1] == *qc)
+ point--;
+ rl_delete_text (point, rl_point);
+ rl_point = point;
+
+ if (matches[1])
+ {
+ for (i = 1; matches[i]; i++)
+ {
+ rp = make_quoted_replacement (matches[i], SINGLE_MATCH, qc);
+ rl_insert_text (rp);
+ rl_insert_text (" ");
+ if (rp != matches[i])
+ xfree (rp);
+ }
+ }
+ else
+ {
+ rp = make_quoted_replacement (matches[0], SINGLE_MATCH, qc);
+ rl_insert_text (rp);
+ rl_insert_text (" ");
+ if (rp != matches[0])
+ xfree (rp);
+ }
+ rl_end_undo_group ();
+}
+
+void
+_rl_free_match_list (matches)
+ char **matches;
+{
+ register int i;
+
+ if (matches == 0)
+ return;
+
+ for (i = 0; matches[i]; i++)
+ xfree (matches[i]);
+ xfree (matches);
+}
+
+/* Complete the word at or before point.
+ WHAT_TO_DO says what to do with the completion.
+ `?' means list the possible completions.
+ TAB means do standard completion.
+ `*' means insert all of the possible completions.
+ `!' means to do standard completion, and list all possible completions if
+ there is more than one.
+ `@' means to do standard completion, and list all possible completions if
+ there is more than one and partial completion is not possible. */
+int
+rl_complete_internal (what_to_do)
+ int what_to_do;
+{
+ char **matches;
+ rl_compentry_func_t *our_func;
+ int start, end, delimiter, found_quote, i, nontrivial_lcd;
+ char *text, *saved_line_buffer;
+ char quote_char;
+#if 1
+ int tlen, mlen;
+#endif
+
+ RL_SETSTATE(RL_STATE_COMPLETING);
+
+ set_completion_defaults (what_to_do);
+
+ saved_line_buffer = rl_line_buffer ? savestring (rl_line_buffer) : (char *)NULL;
+ our_func = rl_completion_entry_function
+ ? rl_completion_entry_function
+ : rl_filename_completion_function;
+ /* We now look backwards for the start of a filename/variable word. */
+ end = rl_point;
+ found_quote = delimiter = 0;
+ quote_char = '\0';
+
+ if (rl_point)
+ /* This (possibly) changes rl_point. If it returns a non-zero char,
+ we know we have an open quote. */
+ quote_char = _rl_find_completion_word (&found_quote, &delimiter);
+
+ start = rl_point;
+ rl_point = end;
+
+ text = rl_copy_text (start, end);
+ matches = gen_completion_matches (text, start, end, our_func, found_quote, quote_char);
+ /* nontrivial_lcd is set if the common prefix adds something to the word
+ being completed. */
+ nontrivial_lcd = matches && strcmp (text, matches[0]) != 0;
+ if (what_to_do == '!' || what_to_do == '@')
+ tlen = strlen (text);
+ xfree (text);
+
+ if (matches == 0)
+ {
+ rl_ding ();
+ FREE (saved_line_buffer);
+ completion_changed_buffer = 0;
+ RL_UNSETSTATE(RL_STATE_COMPLETING);
+ _rl_reset_completion_state ();
+ return (0);
+ }
+
+ /* If we are matching filenames, the attempted completion function will
+ have set rl_filename_completion_desired to a non-zero value. The basic
+ rl_filename_completion_function does this. */
+ i = rl_filename_completion_desired;
+
+ if (postprocess_matches (&matches, i) == 0)
+ {
+ rl_ding ();
+ FREE (saved_line_buffer);
+ completion_changed_buffer = 0;
+ RL_UNSETSTATE(RL_STATE_COMPLETING);
+ _rl_reset_completion_state ();
+ return (0);
+ }
+
+ switch (what_to_do)
+ {
+ case TAB:
+ case '!':
+ case '@':
+ /* Insert the first match with proper quoting. */
+ if (what_to_do == TAB)
+ {
+ if (*matches[0])
+ insert_match (matches[0], start, matches[1] ? MULT_MATCH : SINGLE_MATCH, "e_char);
+ }
+ else if (*matches[0] && matches[1] == 0)
+ /* should we perform the check only if there are multiple matches? */
+ insert_match (matches[0], start, matches[1] ? MULT_MATCH : SINGLE_MATCH, "e_char);
+ else if (*matches[0]) /* what_to_do != TAB && multiple matches */
+ {
+ mlen = *matches[0] ? strlen (matches[0]) : 0;
+ if (mlen >= tlen)
+ insert_match (matches[0], start, matches[1] ? MULT_MATCH : SINGLE_MATCH, "e_char);
+ }
+
+ /* If there are more matches, ring the bell to indicate.
+ If we are in vi mode, Posix.2 says to not ring the bell.
+ If the `show-all-if-ambiguous' variable is set, display
+ all the matches immediately. Otherwise, if this was the
+ only match, and we are hacking files, check the file to
+ see if it was a directory. If so, and the `mark-directories'
+ variable is set, add a '/' to the name. If not, and we
+ are at the end of the line, then add a space. */
+ if (matches[1])
+ {
+ if (what_to_do == '!')
+ {
+ display_matches (matches);
+ break;
+ }
+ else if (what_to_do == '@')
+ {
+ if (nontrivial_lcd == 0)
+ display_matches (matches);
+ break;
+ }
+ else if (rl_editing_mode != vi_mode)
+ rl_ding (); /* There are other matches remaining. */
+ }
+ else
+ append_to_match (matches[0], delimiter, quote_char, nontrivial_lcd);
+
+ break;
+
+ case '*':
+ insert_all_matches (matches, start, "e_char);
+ break;
+
+ case '?':
+ if (rl_completion_display_matches_hook == 0)
+ {
+ _rl_sigcleanup = _rl_complete_sigcleanup;
+ _rl_sigcleanarg = matches;
+ }
+ display_matches (matches);
+ if (_rl_complete_display_matches_interrupt)
+ {
+ matches = 0;
+ _rl_complete_display_matches_interrupt = 0;
+ }
+ _rl_sigcleanup = 0;
+ _rl_sigcleanarg = 0;
+ break;
+
+ default:
+ _rl_ttymsg ("bad value %d for what_to_do in rl_complete", what_to_do);
+ rl_ding ();
+ FREE (saved_line_buffer);
+ RL_UNSETSTATE(RL_STATE_COMPLETING);
+ _rl_free_match_list (matches);
+ _rl_reset_completion_state ();
+ return 1;
+ }
+
+ _rl_free_match_list (matches);
+
+ /* Check to see if the line has changed through all of this manipulation. */
+ if (saved_line_buffer)
+ {
+ completion_changed_buffer = strcmp (rl_line_buffer, saved_line_buffer) != 0;
+ xfree (saved_line_buffer);
+ }
+
+ RL_UNSETSTATE(RL_STATE_COMPLETING);
+ _rl_reset_completion_state ();
+ return 0;
+}
+
+/***************************************************************/
+/* */
+/* Application-callable completion match generator functions */
+/* */
+/***************************************************************/
+
+/* Return an array of (char *) which is a list of completions for TEXT.
+ If there are no completions, return a NULL pointer.
+ The first entry in the returned array is the substitution for TEXT.
+ The remaining entries are the possible completions.
+ The array is terminated with a NULL pointer.
+
+ ENTRY_FUNCTION is a function of two args, and returns a (char *).
+ The first argument is TEXT.
+ The second is a state argument; it should be zero on the first call, and
+ non-zero on subsequent calls. It returns a NULL pointer to the caller
+ when there are no more matches.
+ */
+char **
+rl_completion_matches (text, entry_function)
+ const char *text;
+ rl_compentry_func_t *entry_function;
+{
+ register int i;
+
+ /* Number of slots in match_list. */
+ int match_list_size;
+
+ /* The list of matches. */
+ char **match_list;
+
+ /* Number of matches actually found. */
+ int matches;
+
+ /* Temporary string binder. */
+ char *string;
+
+ matches = 0;
+ match_list_size = 10;
+ match_list = (char **)xmalloc ((match_list_size + 1) * sizeof (char *));
+ match_list[1] = (char *)NULL;
+
+ while (string = (*entry_function) (text, matches))
+ {
+ if (RL_SIG_RECEIVED ())
+ {
+ /* Start at 1 because we don't set matches[0] in this function.
+ Only free the list members if we're building match list from
+ rl_filename_completion_function, since we know that doesn't
+ free the strings it returns. */
+ if (entry_function == rl_filename_completion_function)
+ {
+ for (i = 1; match_list[i]; i++)
+ xfree (match_list[i]);
+ }
+ xfree (match_list);
+ match_list = 0;
+ match_list_size = 0;
+ matches = 0;
+ RL_CHECK_SIGNALS ();
+ }
+
+ if (matches + 1 >= match_list_size)
+ match_list = (char **)xrealloc
+ (match_list, ((match_list_size += 10) + 1) * sizeof (char *));
+
+ if (match_list == 0)
+ return (match_list);
+
+ match_list[++matches] = string;
+ match_list[matches + 1] = (char *)NULL;
+ }
+
+ /* If there were any matches, then look through them finding out the
+ lowest common denominator. That then becomes match_list[0]. */
+ if (matches)
+ compute_lcd_of_matches (match_list, matches, text);
+ else /* There were no matches. */
+ {
+ xfree (match_list);
+ match_list = (char **)NULL;
+ }
+ return (match_list);
+}
+
+/* A completion function for usernames.
+ TEXT contains a partial username preceded by a random
+ character (usually `~'). */
+char *
+rl_username_completion_function (text, state)
+ const char *text;
+ int state;
+{
+#if defined (__WIN32__) || defined (__OPENNT)
+ return (char *)NULL;
+#else /* !__WIN32__ && !__OPENNT) */
+ static char *username = (char *)NULL;
+ static struct passwd *entry;
+ static int namelen, first_char, first_char_loc;
+ char *value;
+
+ if (state == 0)
+ {
+ FREE (username);
+
+ first_char = *text;
+ first_char_loc = first_char == '~';
+
+ username = savestring (&text[first_char_loc]);
+ namelen = strlen (username);
+#if defined (HAVE_GETPWENT)
+ setpwent ();
+#endif
+ }
+
+#if defined (HAVE_GETPWENT)
+ while (entry = getpwent ())
+ {
+ /* Null usernames should result in all users as possible completions. */
+ if (namelen == 0 || (STREQN (username, entry->pw_name, namelen)))
+ break;
+ }
+#endif
+
+ if (entry == 0)
+ {
+#if defined (HAVE_GETPWENT)
+ endpwent ();
+#endif
+ return ((char *)NULL);
+ }
+ else
+ {
+ value = (char *)xmalloc (2 + strlen (entry->pw_name));
+
+ *value = *text;
+
+ strcpy (value + first_char_loc, entry->pw_name);
+
+ if (first_char == '~')
+ rl_filename_completion_desired = 1;
+
+ return (value);
+ }
+#endif /* !__WIN32__ && !__OPENNT */
+}
+
+/* Return non-zero if CONVFN matches FILENAME up to the length of FILENAME
+ (FILENAME_LEN). If _rl_completion_case_fold is set, compare without
+ regard to the alphabetic case of characters. If
+ _rl_completion_case_map is set, make `-' and `_' equivalent. CONVFN is
+ the possibly-converted directory entry; FILENAME is what the user typed. */
+static int
+complete_fncmp (convfn, convlen, filename, filename_len)
+ const char *convfn;
+ int convlen;
+ const char *filename;
+ int filename_len;
+{
+ register char *s1, *s2;
+ int d, len;
+#if defined (HANDLE_MULTIBYTE)
+ size_t v1, v2;
+ mbstate_t ps1, ps2;
+ wchar_t wc1, wc2;
+#endif
+
+#if defined (HANDLE_MULTIBYTE)
+ memset (&ps1, 0, sizeof (mbstate_t));
+ memset (&ps2, 0, sizeof (mbstate_t));
+#endif
+
+ if (filename_len == 0)
+ return 1;
+ if (convlen < filename_len)
+ return 0;
+
+ len = filename_len;
+ s1 = (char *)convfn;
+ s2 = (char *)filename;
+
+ /* Otherwise, if these match up to the length of filename, then
+ it is a match. */
+ if (_rl_completion_case_fold && _rl_completion_case_map)
+ {
+ /* Case-insensitive comparison treating _ and - as equivalent */
+#if defined (HANDLE_MULTIBYTE)
+ if (MB_CUR_MAX > 1 && rl_byte_oriented == 0)
+ {
+ do
+ {
+ v1 = mbrtowc (&wc1, s1, convlen, &ps1);
+ v2 = mbrtowc (&wc2, s2, filename_len, &ps2);
+ if (v1 == 0 && v2 == 0)
+ return 1;
+ else if (MB_INVALIDCH (v1) || MB_INVALIDCH (v2))
+ {
+ if (*s1 != *s2) /* do byte comparison */
+ return 0;
+ else if ((*s1 == '-' || *s1 == '_') && (*s2 == '-' || *s2 == '_'))
+ return 0;
+ s1++; s2++; len--;
+ continue;
+ }
+ wc1 = towlower (wc1);
+ wc2 = towlower (wc2);
+ s1 += v1;
+ s2 += v1;
+ len -= v1;
+ if ((wc1 == L'-' || wc1 == L'_') && (wc2 == L'-' || wc2 == L'_'))
+ continue;
+ if (wc1 != wc2)
+ return 0;
+ }
+ while (len != 0);
+ }
+ else
+#endif
+ {
+ do
+ {
+ d = _rl_to_lower (*s1) - _rl_to_lower (*s2);
+ /* *s1 == [-_] && *s2 == [-_] */
+ if ((*s1 == '-' || *s1 == '_') && (*s2 == '-' || *s2 == '_'))
+ d = 0;
+ if (d != 0)
+ return 0;
+ s1++; s2++; /* already checked convlen >= filename_len */
+ }
+ while (--len != 0);
+ }
+
+ return 1;
+ }
+ else if (_rl_completion_case_fold)
+ {
+#if defined (HANDLE_MULTIBYTE)
+ if (MB_CUR_MAX > 1 && rl_byte_oriented == 0)
+ {
+ do
+ {
+ v1 = mbrtowc (&wc1, s1, convlen, &ps1);
+ v2 = mbrtowc (&wc2, s2, filename_len, &ps2);
+ if (v1 == 0 && v2 == 0)
+ return 1;
+ else if (MB_INVALIDCH (v1) || MB_INVALIDCH (v2))
+ {
+ if (*s1 != *s2) /* do byte comparison */
+ return 0;
+ s1++; s2++; len--;
+ continue;
+ }
+ wc1 = towlower (wc1);
+ wc2 = towlower (wc2);
+ if (wc1 != wc2)
+ return 0;
+ s1 += v1;
+ s2 += v1;
+ len -= v1;
+ }
+ while (len != 0);
+ return 1;
+ }
+ else
+#endif
+ if ((_rl_to_lower (convfn[0]) == _rl_to_lower (filename[0])) &&
+ (convlen >= filename_len) &&
+ (_rl_strnicmp (filename, convfn, filename_len) == 0))
+ return 1;
+ }
+ else
+ {
+ if ((convfn[0] == filename[0]) &&
+ (convlen >= filename_len) &&
+ (strncmp (filename, convfn, filename_len) == 0))
+ return 1;
+ }
+ return 0;
+}
+
+/* Okay, now we write the entry_function for filename completion. In the
+ general case. Note that completion in the shell is a little different
+ because of all the pathnames that must be followed when looking up the
+ completion for a command. */
+char *
+rl_filename_completion_function (text, state)
+ const char *text;
+ int state;
+{
+ static DIR *directory = (DIR *)NULL;
+ static char *filename = (char *)NULL;
+ static char *dirname = (char *)NULL;
+ static char *users_dirname = (char *)NULL;
+ static int filename_len;
+ char *temp, *dentry, *convfn;
+ int dirlen, dentlen, convlen;
+ struct dirent *entry;
+
+ /* If we don't have any state, then do some initialization. */
+ if (state == 0)
+ {
+ /* If we were interrupted before closing the directory or reading
+ all of its contents, close it. */
+ if (directory)
+ {
+ closedir (directory);
+ directory = (DIR *)NULL;
+ }
+ FREE (dirname);
+ FREE (filename);
+ FREE (users_dirname);
+
+ filename = savestring (text);
+ if (*text == 0)
+ text = ".";
+ dirname = savestring (text);
+
+ temp = strrchr (dirname, '/');
+
+#if defined (__MSDOS__)
+ /* special hack for //X/... */
+ if (dirname[0] == '/' && dirname[1] == '/' && ISALPHA ((unsigned char)dirname[2]) && dirname[3] == '/')
+ temp = strrchr (dirname + 3, '/');
+#endif
+
+ if (temp)
+ {
+ strcpy (filename, ++temp);
+ *temp = '\0';
+ }
+#if defined (__MSDOS__)
+ /* searches from current directory on the drive */
+ else if (ISALPHA ((unsigned char)dirname[0]) && dirname[1] == ':')
+ {
+ strcpy (filename, dirname + 2);
+ dirname[2] = '\0';
+ }
+#endif
+ else
+ {
+ dirname[0] = '.';
+ dirname[1] = '\0';
+ }
+
+ /* We aren't done yet. We also support the "~user" syntax. */
+
+ /* Save the version of the directory that the user typed, dequoting
+ it if necessary. */
+ if (rl_completion_found_quote && rl_filename_dequoting_function)
+ users_dirname = (*rl_filename_dequoting_function) (dirname, rl_completion_quote_character);
+ else
+ users_dirname = savestring (dirname);
+
+ if (*dirname == '~')
+ {
+ temp = tilde_expand (dirname);
+ xfree (dirname);
+ dirname = temp;
+ }
+
+ /* We have saved the possibly-dequoted version of the directory name
+ the user typed. Now transform the directory name we're going to
+ pass to opendir(2). The directory rewrite hook modifies only the
+ directory name; the directory completion hook modifies both the
+ directory name passed to opendir(2) and the version the user
+ typed. Both the directory completion and rewrite hooks should perform
+ any necessary dequoting. The hook functions return 1 if they modify
+ the directory name argument. If either hook returns 0, it should
+ not modify the directory name pointer passed as an argument. */
+ if (rl_directory_rewrite_hook)
+ (*rl_directory_rewrite_hook) (&dirname);
+ else if (rl_directory_completion_hook && (*rl_directory_completion_hook) (&dirname))
+ {
+ xfree (users_dirname);
+ users_dirname = savestring (dirname);
+ }
+ else if (rl_completion_found_quote && rl_filename_dequoting_function)
+ {
+ /* delete single and double quotes */
+ xfree (dirname);
+ dirname = savestring (users_dirname);
+ }
+ directory = opendir (dirname);
+
+ /* Now dequote a non-null filename. FILENAME will not be NULL, but may
+ be empty. */
+ if (*filename && rl_completion_found_quote && rl_filename_dequoting_function)
+ {
+ /* delete single and double quotes */
+ temp = (*rl_filename_dequoting_function) (filename, rl_completion_quote_character);
+ xfree (filename);
+ filename = temp;
+ }
+ filename_len = strlen (filename);
+
+ rl_filename_completion_desired = 1;
+ }
+
+ /* At this point we should entertain the possibility of hacking wildcarded
+ filenames, like /usr/man/man<WILD>/te<TAB>. If the directory name
+ contains globbing characters, then build an array of directories, and
+ then map over that list while completing. */
+ /* *** UNIMPLEMENTED *** */
+
+ /* Now that we have some state, we can read the directory. */
+
+ entry = (struct dirent *)NULL;
+ while (directory && (entry = readdir (directory)))
+ {
+ convfn = dentry = entry->d_name;
+ convlen = dentlen = D_NAMLEN (entry);
+
+ if (rl_filename_rewrite_hook)
+ {
+ convfn = (*rl_filename_rewrite_hook) (dentry, dentlen);
+ convlen = (convfn == dentry) ? dentlen : strlen (convfn);
+ }
+
+ /* Special case for no filename. If the user has disabled the
+ `match-hidden-files' variable, skip filenames beginning with `.'.
+ All other entries except "." and ".." match. */
+ if (filename_len == 0)
+ {
+ if (_rl_match_hidden_files == 0 && HIDDEN_FILE (convfn))
+ continue;
+
+ if (convfn[0] != '.' ||
+ (convfn[1] && (convfn[1] != '.' || convfn[2])))
+ break;
+ }
+ else
+ {
+ if (complete_fncmp (convfn, convlen, filename, filename_len))
+ break;
+ }
+ }
+
+ if (entry == 0)
+ {
+ if (directory)
+ {
+ closedir (directory);
+ directory = (DIR *)NULL;
+ }
+ if (dirname)
+ {
+ xfree (dirname);
+ dirname = (char *)NULL;
+ }
+ if (filename)
+ {
+ xfree (filename);
+ filename = (char *)NULL;
+ }
+ if (users_dirname)
+ {
+ xfree (users_dirname);
+ users_dirname = (char *)NULL;
+ }
+
+ return (char *)NULL;
+ }
+ else
+ {
+ /* dirname && (strcmp (dirname, ".") != 0) */
+ if (dirname && (dirname[0] != '.' || dirname[1]))
+ {
+ if (rl_complete_with_tilde_expansion && *users_dirname == '~')
+ {
+ dirlen = strlen (dirname);
+ temp = (char *)xmalloc (2 + dirlen + D_NAMLEN (entry));
+ strcpy (temp, dirname);
+ /* Canonicalization cuts off any final slash present. We
+ may need to add it back. */
+ if (dirname[dirlen - 1] != '/')
+ {
+ temp[dirlen++] = '/';
+ temp[dirlen] = '\0';
+ }
+ }
+ else
+ {
+ dirlen = strlen (users_dirname);
+ temp = (char *)xmalloc (2 + dirlen + D_NAMLEN (entry));
+ strcpy (temp, users_dirname);
+ /* Make sure that temp has a trailing slash here. */
+ if (users_dirname[dirlen - 1] != '/')
+ temp[dirlen++] = '/';
+ }
+
+ strcpy (temp + dirlen, convfn);
+ }
+ else
+ temp = savestring (convfn);
+
+ if (convfn != dentry)
+ xfree (convfn);
+
+ return (temp);
+ }
+}
+
+/* An initial implementation of a menu completion function a la tcsh. The
+ first time (if the last readline command was not rl_old_menu_complete), we
+ generate the list of matches. This code is very similar to the code in
+ rl_complete_internal -- there should be a way to combine the two. Then,
+ for each item in the list of matches, we insert the match in an undoable
+ fashion, with the appropriate character appended (this happens on the
+ second and subsequent consecutive calls to rl_old_menu_complete). When we
+ hit the end of the match list, we restore the original unmatched text,
+ ring the bell, and reset the counter to zero. */
+int
+rl_old_menu_complete (count, invoking_key)
+ int count, invoking_key;
+{
+ rl_compentry_func_t *our_func;
+ int matching_filenames, found_quote;
+
+ static char *orig_text;
+ static char **matches = (char **)0;
+ static int match_list_index = 0;
+ static int match_list_size = 0;
+ static int orig_start, orig_end;
+ static char quote_char;
+ static int delimiter;
+
+ /* The first time through, we generate the list of matches and set things
+ up to insert them. */
+ if (rl_last_func != rl_old_menu_complete)
+ {
+ /* Clean up from previous call, if any. */
+ FREE (orig_text);
+ if (matches)
+ _rl_free_match_list (matches);
+
+ match_list_index = match_list_size = 0;
+ matches = (char **)NULL;
+
+ rl_completion_invoking_key = invoking_key;
+
+ RL_SETSTATE(RL_STATE_COMPLETING);
+
+ /* Only the completion entry function can change these. */
+ set_completion_defaults ('%');
+
+ our_func = rl_menu_completion_entry_function;
+ if (our_func == 0)
+ our_func = rl_completion_entry_function
+ ? rl_completion_entry_function
+ : rl_filename_completion_function;
+
+ /* We now look backwards for the start of a filename/variable word. */
+ orig_end = rl_point;
+ found_quote = delimiter = 0;
+ quote_char = '\0';
+
+ if (rl_point)
+ /* This (possibly) changes rl_point. If it returns a non-zero char,
+ we know we have an open quote. */
+ quote_char = _rl_find_completion_word (&found_quote, &delimiter);
+
+ orig_start = rl_point;
+ rl_point = orig_end;
+
+ orig_text = rl_copy_text (orig_start, orig_end);
+ matches = gen_completion_matches (orig_text, orig_start, orig_end,
+ our_func, found_quote, quote_char);
+
+ /* If we are matching filenames, the attempted completion function will
+ have set rl_filename_completion_desired to a non-zero value. The basic
+ rl_filename_completion_function does this. */
+ matching_filenames = rl_filename_completion_desired;
+
+ if (matches == 0 || postprocess_matches (&matches, matching_filenames) == 0)
+ {
+ rl_ding ();
+ FREE (matches);
+ matches = (char **)0;
+ FREE (orig_text);
+ orig_text = (char *)0;
+ completion_changed_buffer = 0;
+ RL_UNSETSTATE(RL_STATE_COMPLETING);
+ return (0);
+ }
+
+ RL_UNSETSTATE(RL_STATE_COMPLETING);
+
+ for (match_list_size = 0; matches[match_list_size]; match_list_size++)
+ ;
+ /* matches[0] is lcd if match_list_size > 1, but the circular buffer
+ code below should take care of it. */
+
+ if (match_list_size > 1 && _rl_complete_show_all)
+ display_matches (matches);
+ }
+
+ /* Now we have the list of matches. Replace the text between
+ rl_line_buffer[orig_start] and rl_line_buffer[rl_point] with
+ matches[match_list_index], and add any necessary closing char. */
+
+ if (matches == 0 || match_list_size == 0)
+ {
+ rl_ding ();
+ FREE (matches);
+ matches = (char **)0;
+ completion_changed_buffer = 0;
+ return (0);
+ }
+
+ match_list_index += count;
+ if (match_list_index < 0)
+ {
+ while (match_list_index < 0)
+ match_list_index += match_list_size;
+ }
+ else
+ match_list_index %= match_list_size;
+
+ if (match_list_index == 0 && match_list_size > 1)
+ {
+ rl_ding ();
+ insert_match (orig_text, orig_start, MULT_MATCH, "e_char);
+ }
+ else
+ {
+ insert_match (matches[match_list_index], orig_start, SINGLE_MATCH, "e_char);
+ append_to_match (matches[match_list_index], delimiter, quote_char,
+ strcmp (orig_text, matches[match_list_index]));
+ }
+
+ completion_changed_buffer = 1;
+ return (0);
+}
+
+int
+rl_menu_complete (count, ignore)
+ int count, ignore;
+{
+ rl_compentry_func_t *our_func;
+ int matching_filenames, found_quote;
+
+ static char *orig_text;
+ static char **matches = (char **)0;
+ static int match_list_index = 0;
+ static int match_list_size = 0;
+ static int nontrivial_lcd = 0;
+ static int full_completion = 0; /* set to 1 if menu completion should reinitialize on next call */
+ static int orig_start, orig_end;
+ static char quote_char;
+ static int delimiter, cstate;
+
+ /* The first time through, we generate the list of matches and set things
+ up to insert them. */
+ if ((rl_last_func != rl_menu_complete && rl_last_func != rl_backward_menu_complete) || full_completion)
+ {
+ /* Clean up from previous call, if any. */
+ FREE (orig_text);
+ if (matches)
+ _rl_free_match_list (matches);
+
+ match_list_index = match_list_size = 0;
+ matches = (char **)NULL;
+
+ full_completion = 0;
+
+ RL_SETSTATE(RL_STATE_COMPLETING);
+
+ /* Only the completion entry function can change these. */
+ set_completion_defaults ('%');
+
+ our_func = rl_menu_completion_entry_function;
+ if (our_func == 0)
+ our_func = rl_completion_entry_function
+ ? rl_completion_entry_function
+ : rl_filename_completion_function;
+
+ /* We now look backwards for the start of a filename/variable word. */
+ orig_end = rl_point;
+ found_quote = delimiter = 0;
+ quote_char = '\0';
+
+ if (rl_point)
+ /* This (possibly) changes rl_point. If it returns a non-zero char,
+ we know we have an open quote. */
+ quote_char = _rl_find_completion_word (&found_quote, &delimiter);
+
+ orig_start = rl_point;
+ rl_point = orig_end;
+
+ orig_text = rl_copy_text (orig_start, orig_end);
+ matches = gen_completion_matches (orig_text, orig_start, orig_end,
+ our_func, found_quote, quote_char);
+
+ nontrivial_lcd = matches && strcmp (orig_text, matches[0]) != 0;
+
+ /* If we are matching filenames, the attempted completion function will
+ have set rl_filename_completion_desired to a non-zero value. The basic
+ rl_filename_completion_function does this. */
+ matching_filenames = rl_filename_completion_desired;
+
+ if (matches == 0 || postprocess_matches (&matches, matching_filenames) == 0)
+ {
+ rl_ding ();
+ FREE (matches);
+ matches = (char **)0;
+ FREE (orig_text);
+ orig_text = (char *)0;
+ completion_changed_buffer = 0;
+ RL_UNSETSTATE(RL_STATE_COMPLETING);
+ return (0);
+ }
+
+ RL_UNSETSTATE(RL_STATE_COMPLETING);
+
+ for (match_list_size = 0; matches[match_list_size]; match_list_size++)
+ ;
+
+ if (match_list_size == 0)
+ {
+ rl_ding ();
+ FREE (matches);
+ matches = (char **)0;
+ match_list_index = 0;
+ completion_changed_buffer = 0;
+ return (0);
+ }
+
+ /* matches[0] is lcd if match_list_size > 1, but the circular buffer
+ code below should take care of it. */
+ if (*matches[0])
+ {
+ insert_match (matches[0], orig_start, matches[1] ? MULT_MATCH : SINGLE_MATCH, "e_char);
+ orig_end = orig_start + strlen (matches[0]);
+ completion_changed_buffer = STREQ (orig_text, matches[0]) == 0;
+ }
+
+ if (match_list_size > 1 && _rl_complete_show_all)
+ {
+ display_matches (matches);
+ /* If there are so many matches that the user has to be asked
+ whether or not he wants to see the matches, menu completion
+ is unwieldy. */
+ if (rl_completion_query_items > 0 && match_list_size >= rl_completion_query_items)
+ {
+ rl_ding ();
+ FREE (matches);
+ matches = (char **)0;
+ full_completion = 1;
+ return (0);
+ }
+ else if (_rl_menu_complete_prefix_first)
+ {
+ rl_ding ();
+ return (0);
+ }
+ }
+ else if (match_list_size <= 1)
+ {
+ append_to_match (matches[0], delimiter, quote_char, nontrivial_lcd);
+ full_completion = 1;
+ return (0);
+ }
+ else if (_rl_menu_complete_prefix_first && match_list_size > 1)
+ {
+ rl_ding ();
+ return (0);
+ }
+ }
+
+ /* Now we have the list of matches. Replace the text between
+ rl_line_buffer[orig_start] and rl_line_buffer[rl_point] with
+ matches[match_list_index], and add any necessary closing char. */
+
+ if (matches == 0 || match_list_size == 0)
+ {
+ rl_ding ();
+ FREE (matches);
+ matches = (char **)0;
+ completion_changed_buffer = 0;
+ return (0);
+ }
+
+ match_list_index += count;
+ if (match_list_index < 0)
+ {
+ while (match_list_index < 0)
+ match_list_index += match_list_size;
+ }
+ else
+ match_list_index %= match_list_size;
+
+ if (match_list_index == 0 && match_list_size > 1)
+ {
+ rl_ding ();
+ insert_match (matches[0], orig_start, MULT_MATCH, "e_char);
+ }
+ else
+ {
+ insert_match (matches[match_list_index], orig_start, SINGLE_MATCH, "e_char);
+ append_to_match (matches[match_list_index], delimiter, quote_char,
+ strcmp (orig_text, matches[match_list_index]));
+ }
+
+ completion_changed_buffer = 1;
+ return (0);
+}
+
+int
+rl_backward_menu_complete (count, key)
+ int count, key;
+{
+ /* Positive arguments to backward-menu-complete translate into negative
+ arguments for menu-complete, and vice versa. */
+ return (rl_menu_complete (-count, key));
+}
--- /dev/null
+# This makefile for Readline library documentation is in -*- text -*- mode.
+# Emacs likes it that way.
+RM = rm -f
+
+MAKEINFO = makeinfo
+TEXI2DVI = texi2dvi
+TEXI2HTML = texi2html
+QUIETPS = #set this to -q to shut up dvips
+DVIPS = dvips -D 300 $(QUIETPS) -o $@ # tricky
+
+INSTALL_DATA = cp
+infodir = /usr/local/info
+
+RLSRC = rlman.texinfo rluser.texinfo rltech.texinfo
+HISTSRC = hist.texinfo hsuser.texinfo hstech.texinfo
+
+DVIOBJ = readline.dvi history.dvi
+INFOOBJ = readline.info history.info
+PSOBJ = readline.ps history.ps
+HTMLOBJ = readline.html history.html
+
+all: info dvi html ps
+nodvi: info html
+
+readline.dvi: $(RLSRC)
+ $(TEXI2DVI) rlman.texinfo
+ mv rlman.dvi readline.dvi
+
+readline.info: $(RLSRC)
+ $(MAKEINFO) --no-split -o $@ rlman.texinfo
+
+history.dvi: ${HISTSRC}
+ $(TEXI2DVI) hist.texinfo
+ mv hist.dvi history.dvi
+
+history.info: ${HISTSRC}
+ $(MAKEINFO) --no-split -o $@ hist.texinfo
+
+readline.ps: readline.dvi
+ $(RM) $@
+ $(DVIPS) readline.dvi
+
+history.ps: history.dvi
+ $(RM) $@
+ $(DVIPS) history.dvi
+
+readline.html: ${RLSRC}
+ $(TEXI2HTML) rlman.texinfo
+ sed -e 's:rlman.html:readline.html:' -e 's:rlman_toc.html:readline_toc.html:' rlman.html > readline.html
+ sed -e 's:rlman.html:readline.html:' -e 's:rlman_toc.html:readline_toc.html:' rlman_toc.html > readline_toc.html
+ $(RM) rlman.html rlman_toc.html
+
+history.html: ${HISTSRC}
+ $(TEXI2HTML) hist.texinfo
+ sed -e 's:hist.html:history.html:' -e 's:hist_toc.html:history_toc.html:' hist.html > history.html
+ sed -e 's:hist.html:history.html:' -e 's:hist_toc.html:history_toc.html:' hist_toc.html > history_toc.html
+ $(RM) hist.html hist_toc.html
+
+info: $(INFOOBJ)
+dvi: $(DVIOBJ)
+ps: $(PSOBJ)
+html: $(HTMLOBJ)
+
+clean:
+ $(RM) *.aux *.cp *.fn *.ky *.log *.pg *.toc *.tp *.vr *.cps *.pgs \
+ *.fns *.kys *.tps *.vrs *.o core
+
+distclean: clean
+mostlyclean: clean
+
+maintainer-clean: clean
+ $(RM) *.dvi *.info *.info-* *.ps *.html
+
+install: info
+ ${INSTALL_DATA} readline.info $(infodir)/readline.info
+ ${INSTALL_DATA} history.info $(infodir)/history.info
static int lastc, eof_found;
int c, code, lk;
- lastc = -1;
+ lastc = EOF;
eof_found = 0;
#if !defined (READLINE_CALLBACKS)
#endif
}
- /* EOF typed to a non-blank line is a <NL>. If we want to change this,
- to force any existing line to be ignored when read(2) reads EOF,
- for example, this is the place to change. */
+ /* EOF typed to a non-blank line is ^D the first time, EOF the second
+ time in a row. This won't return any partial line read from the tty.
+ If we want to change this, to force any existing line to be returned
+ when read(2) reads EOF, for example, this is the place to change. */
if (c == EOF && rl_end)
- c = NEWLINE;
+ {
+ if (RL_SIG_RECEIVED ())
+ {
+ RL_CHECK_SIGNALS ();
+ if (rl_signal_event_hook)
+ (*rl_signal_event_hook) (); /* XXX */
+ }
+
+ /* XXX - reading two consecutive EOFs returns EOF */
+ if (RL_ISSTATE (RL_STATE_TERMPREPPED))
+ {
+ if (lastc == _rl_eof_char || lastc == EOF)
+ rl_end = 0;
+ else
+ c = _rl_eof_char;
+ }
+ else
+ c = NEWLINE;
+ }
/* The character _rl_eof_char typed to blank line, and not as the
- previous character is interpreted as EOF. */
- if (((c == _rl_eof_char && lastc != c) || c == EOF) && !rl_end)
+ previous character is interpreted as EOF. This doesn't work when
+ READLINE_CALLBACKS is defined, so hitting a series of ^Ds will
+ erase all the chars on the line and then return EOF. */
+ if (((c == _rl_eof_char && lastc != c) || c == EOF) && rl_end == 0)
{
#if defined (READLINE_CALLBACKS)
RL_SETSTATE(RL_STATE_DONE);
--- /dev/null
+/* readline.c -- a general facility for reading lines of input
+ with emacs style editing and completion. */
+
+/* Copyright (C) 1987-2013 Free Software Foundation, Inc.
+
+ This file is part of the GNU Readline Library (Readline), a library
+ for reading lines of text with interactive input and history editing.
+
+ Readline is free software: you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation, either version 3 of the License, or
+ (at your option) any later version.
+
+ Readline is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with Readline. If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#define READLINE_LIBRARY
+
+#if defined (HAVE_CONFIG_H)
+# include <config.h>
+#endif
+
+#include <sys/types.h>
+#include "posixstat.h"
+#include <fcntl.h>
+#if defined (HAVE_SYS_FILE_H)
+# include <sys/file.h>
+#endif /* HAVE_SYS_FILE_H */
+
+#if defined (HAVE_UNISTD_H)
+# include <unistd.h>
+#endif /* HAVE_UNISTD_H */
+
+#if defined (HAVE_STDLIB_H)
+# include <stdlib.h>
+#else
+# include "ansi_stdlib.h"
+#endif /* HAVE_STDLIB_H */
+
+#if defined (HAVE_LOCALE_H)
+# include <locale.h>
+#endif
+
+#include <stdio.h>
+#include "posixjmp.h"
+#include <errno.h>
+
+#if !defined (errno)
+extern int errno;
+#endif /* !errno */
+
+/* System-specific feature definitions and include files. */
+#include "rldefs.h"
+#include "rlmbutil.h"
+
+#if defined (__EMX__)
+# define INCL_DOSPROCESS
+# include <os2.h>
+#endif /* __EMX__ */
+
+/* Some standard library routines. */
+#include "readline.h"
+#include "history.h"
+
+#include "rlprivate.h"
+#include "rlshell.h"
+#include "xmalloc.h"
+
+#ifndef RL_LIBRARY_VERSION
+# define RL_LIBRARY_VERSION "5.1"
+#endif
+
+#ifndef RL_READLINE_VERSION
+# define RL_READLINE_VERSION 0x0501
+#endif
+
+extern void _rl_free_history_entry PARAMS((HIST_ENTRY *));
+
+#if defined (COLOR_SUPPORT)
+extern void _rl_parse_colors PARAMS((void)); /* XXX */
+#endif
+
+
+/* Forward declarations used in this file. */
+static char *readline_internal PARAMS((void));
+static void readline_initialize_everything PARAMS((void));
+
+static void bind_arrow_keys_internal PARAMS((Keymap));
+static void bind_arrow_keys PARAMS((void));
+
+static void bind_bracketed_paste_prefix PARAMS((void));
+
+static void readline_default_bindings PARAMS((void));
+static void reset_default_bindings PARAMS((void));
+
+static int _rl_subseq_result PARAMS((int, Keymap, int, int));
+static int _rl_subseq_getchar PARAMS((int));
+
+/* **************************************************************** */
+/* */
+/* Line editing input utility */
+/* */
+/* **************************************************************** */
+
+const char *rl_library_version = RL_LIBRARY_VERSION;
+
+int rl_readline_version = RL_READLINE_VERSION;
+
+/* True if this is `real' readline as opposed to some stub substitute. */
+int rl_gnu_readline_p = 1;
+
+/* A pointer to the keymap that is currently in use.
+ By default, it is the standard emacs keymap. */
+Keymap _rl_keymap = emacs_standard_keymap;
+
+/* The current style of editing. */
+int rl_editing_mode = emacs_mode;
+
+/* The current insert mode: input (the default) or overwrite */
+int rl_insert_mode = RL_IM_DEFAULT;
+
+/* Non-zero if we called this function from _rl_dispatch(). It's present
+ so functions can find out whether they were called from a key binding
+ or directly from an application. */
+int rl_dispatching;
+
+/* Non-zero if the previous command was a kill command. */
+int _rl_last_command_was_kill = 0;
+
+/* The current value of the numeric argument specified by the user. */
+int rl_numeric_arg = 1;
+
+/* Non-zero if an argument was typed. */
+int rl_explicit_arg = 0;
+
+/* Temporary value used while generating the argument. */
+int rl_arg_sign = 1;
+
+/* Non-zero means we have been called at least once before. */
+static int rl_initialized;
+
+#if 0
+/* If non-zero, this program is running in an EMACS buffer. */
+static int running_in_emacs;
+#endif
+
+/* Flags word encapsulating the current readline state. */
+int rl_readline_state = RL_STATE_NONE;
+
+/* The current offset in the current input line. */
+int rl_point;
+
+/* Mark in the current input line. */
+int rl_mark;
+
+/* Length of the current input line. */
+int rl_end;
+
+/* Make this non-zero to return the current input_line. */
+int rl_done;
+
+/* The last function executed by readline. */
+rl_command_func_t *rl_last_func = (rl_command_func_t *)NULL;
+
+/* Top level environment for readline_internal (). */
+procenv_t _rl_top_level;
+
+/* The streams we interact with. */
+FILE *_rl_in_stream, *_rl_out_stream;
+
+/* The names of the streams that we do input and output to. */
+FILE *rl_instream = (FILE *)NULL;
+FILE *rl_outstream = (FILE *)NULL;
+
+/* Non-zero means echo characters as they are read. Defaults to no echo;
+ set to 1 if there is a controlling terminal, we can get its attributes,
+ and the attributes include `echo'. Look at rltty.c:prepare_terminal_settings
+ for the code that sets it. */
+int _rl_echoing_p = 0;
+
+/* Current prompt. */
+char *rl_prompt = (char *)NULL;
+int rl_visible_prompt_length = 0;
+
+/* Set to non-zero by calling application if it has already printed rl_prompt
+ and does not want readline to do it the first time. */
+int rl_already_prompted = 0;
+
+/* The number of characters read in order to type this complete command. */
+int rl_key_sequence_length = 0;
+
+/* If non-zero, then this is the address of a function to call just
+ before readline_internal_setup () prints the first prompt. */
+rl_hook_func_t *rl_startup_hook = (rl_hook_func_t *)NULL;
+
+/* If non-zero, this is the address of a function to call just before
+ readline_internal_setup () returns and readline_internal starts
+ reading input characters. */
+rl_hook_func_t *rl_pre_input_hook = (rl_hook_func_t *)NULL;
+
+/* What we use internally. You should always refer to RL_LINE_BUFFER. */
+static char *the_line;
+
+/* The character that can generate an EOF. Really read from
+ the terminal driver... just defaulted here. */
+int _rl_eof_char = CTRL ('D');
+
+/* Non-zero makes this the next keystroke to read. */
+int rl_pending_input = 0;
+
+/* Pointer to a useful terminal name. */
+const char *rl_terminal_name = (const char *)NULL;
+
+/* Non-zero means to always use horizontal scrolling in line display. */
+int _rl_horizontal_scroll_mode = 0;
+
+/* Non-zero means to display an asterisk at the starts of history lines
+ which have been modified. */
+int _rl_mark_modified_lines = 0;
+
+/* The style of `bell' notification preferred. This can be set to NO_BELL,
+ AUDIBLE_BELL, or VISIBLE_BELL. */
+int _rl_bell_preference = AUDIBLE_BELL;
+
+/* String inserted into the line by rl_insert_comment (). */
+char *_rl_comment_begin;
+
+/* Keymap holding the function currently being executed. */
+Keymap rl_executing_keymap;
+
+/* Keymap we're currently using to dispatch. */
+Keymap _rl_dispatching_keymap;
+
+/* Non-zero means to erase entire line, including prompt, on empty input lines. */
+int rl_erase_empty_line = 0;
+
+/* Non-zero means to read only this many characters rather than up to a
+ character bound to accept-line. */
+int rl_num_chars_to_read;
+
+/* Line buffer and maintenance. */
+char *rl_line_buffer = (char *)NULL;
+int rl_line_buffer_len = 0;
+
+/* Key sequence `contexts' */
+_rl_keyseq_cxt *_rl_kscxt = 0;
+
+int rl_executing_key;
+char *rl_executing_keyseq = 0;
+int _rl_executing_keyseq_size = 0;
+
+/* Timeout (specified in milliseconds) when reading characters making up an
+ ambiguous multiple-key sequence */
+int _rl_keyseq_timeout = 500;
+
+#define RESIZE_KEYSEQ_BUFFER() \
+ do \
+ { \
+ if (rl_key_sequence_length + 2 >= _rl_executing_keyseq_size) \
+ { \
+ _rl_executing_keyseq_size += 16; \
+ rl_executing_keyseq = xrealloc (rl_executing_keyseq, _rl_executing_keyseq_size); \
+ } \
+ } \
+ while (0);
+
+/* Forward declarations used by the display, termcap, and history code. */
+
+/* **************************************************************** */
+/* */
+/* `Forward' declarations */
+/* */
+/* **************************************************************** */
+
+/* Non-zero means do not parse any lines other than comments and
+ parser directives. */
+unsigned char _rl_parsing_conditionalized_out = 0;
+
+/* Non-zero means to convert characters with the meta bit set to
+ escape-prefixed characters so we can indirect through
+ emacs_meta_keymap or vi_escape_keymap. */
+int _rl_convert_meta_chars_to_ascii = 1;
+
+/* Non-zero means to output characters with the meta bit set directly
+ rather than as a meta-prefixed escape sequence. */
+int _rl_output_meta_chars = 0;
+
+/* Non-zero means to look at the termios special characters and bind
+ them to equivalent readline functions at startup. */
+int _rl_bind_stty_chars = 1;
+
+/* Non-zero means to go through the history list at every newline (or
+ whenever rl_done is set and readline returns) and revert each line to
+ its initial state. */
+int _rl_revert_all_at_newline = 0;
+
+/* Non-zero means to honor the termios ECHOCTL bit and echo control
+ characters corresponding to keyboard-generated signals. */
+int _rl_echo_control_chars = 1;
+
+/* Non-zero means to prefix the displayed prompt with a character indicating
+ the editing mode: @ for emacs, : for vi-command, + for vi-insert. */
+int _rl_show_mode_in_prompt = 0;
+
+/* Non-zero means to attempt to put the terminal in `bracketed paste mode',
+ where it will prefix pasted text with an escape sequence and send
+ another to mark the end of the paste. */
+int _rl_enable_bracketed_paste = 0;
+
+/* **************************************************************** */
+/* */
+/* Top Level Functions */
+/* */
+/* **************************************************************** */
+
+/* Non-zero means treat 0200 bit in terminal input as Meta bit. */
+int _rl_meta_flag = 0; /* Forward declaration */
+
+/* Set up the prompt and expand it. Called from readline() and
+ rl_callback_handler_install (). */
+int
+rl_set_prompt (prompt)
+ const char *prompt;
+{
+ FREE (rl_prompt);
+ rl_prompt = prompt ? savestring (prompt) : (char *)NULL;
+ rl_display_prompt = rl_prompt ? rl_prompt : "";
+
+ rl_visible_prompt_length = rl_expand_prompt (rl_prompt);
+ return 0;
+}
+
+/* Read a line of input. Prompt with PROMPT. An empty PROMPT means
+ none. A return value of NULL means that EOF was encountered. */
+char *
+readline (prompt)
+ const char *prompt;
+{
+ char *value;
+#if 0
+ int in_callback;
+#endif
+
+ /* If we are at EOF return a NULL string. */
+ if (rl_pending_input == EOF)
+ {
+ rl_clear_pending_input ();
+ return ((char *)NULL);
+ }
+
+#if 0
+ /* If readline() is called after installing a callback handler, temporarily
+ turn off the callback state to avoid ensuing messiness. Patch supplied
+ by the gdb folks. XXX -- disabled. This can be fooled and readline
+ left in a strange state by a poorly-timed longjmp. */
+ if (in_callback = RL_ISSTATE (RL_STATE_CALLBACK))
+ RL_UNSETSTATE (RL_STATE_CALLBACK);
+#endif
+
+ rl_set_prompt (prompt);
+
+ rl_initialize ();
+ if (rl_prep_term_function)
+ (*rl_prep_term_function) (_rl_meta_flag);
+
+#if defined (HANDLE_SIGNALS)
+ rl_set_signals ();
+#endif
+
+ value = readline_internal ();
+ if (rl_deprep_term_function)
+ (*rl_deprep_term_function) ();
+
+#if defined (HANDLE_SIGNALS)
+ rl_clear_signals ();
+#endif
+
+#if 0
+ if (in_callback)
+ RL_SETSTATE (RL_STATE_CALLBACK);
+#endif
+
+#if HAVE_DECL_AUDIT_TTY && defined (ENABLE_TTY_AUDIT_SUPPORT)
+ if (value)
+ _rl_audit_tty (value);
+#endif
+
+ return (value);
+}
+
+#if defined (READLINE_CALLBACKS)
+# define STATIC_CALLBACK
+#else
+# define STATIC_CALLBACK static
+#endif
+
+STATIC_CALLBACK void
+readline_internal_setup ()
+{
+ char *nprompt;
+
+ _rl_in_stream = rl_instream;
+ _rl_out_stream = rl_outstream;
+
+ /* Enable the meta key only for the duration of readline(), if this
+ terminal has one and the terminal has been initialized */
+ if (_rl_enable_meta & RL_ISSTATE (RL_STATE_TERMPREPPED))
+ _rl_enable_meta_key ();
+
+ if (rl_startup_hook)
+ (*rl_startup_hook) ();
+
+#if defined (VI_MODE)
+ if (rl_editing_mode == vi_mode)
+ rl_vi_insertion_mode (1, 'i'); /* don't want to reset last */
+#endif /* VI_MODE */
+
+ /* If we're not echoing, we still want to at least print a prompt, because
+ rl_redisplay will not do it for us. If the calling application has a
+ custom redisplay function, though, let that function handle it. */
+ if (_rl_echoing_p == 0 && rl_redisplay_function == rl_redisplay)
+ {
+ if (rl_prompt && rl_already_prompted == 0)
+ {
+ nprompt = _rl_strip_prompt (rl_prompt);
+ fprintf (_rl_out_stream, "%s", nprompt);
+ fflush (_rl_out_stream);
+ xfree (nprompt);
+ }
+ }
+ else
+ {
+ if (rl_prompt && rl_already_prompted)
+ rl_on_new_line_with_prompt ();
+ else
+ rl_on_new_line ();
+ (*rl_redisplay_function) ();
+ }
+
+ if (rl_pre_input_hook)
+ (*rl_pre_input_hook) ();
+
+ RL_CHECK_SIGNALS ();
+}
+
+STATIC_CALLBACK char *
+readline_internal_teardown (eof)
+ int eof;
+{
+ char *temp;
+ HIST_ENTRY *entry;
+
+ RL_CHECK_SIGNALS ();
+
+ /* Restore the original of this history line, iff the line that we
+ are editing was originally in the history, AND the line has changed. */
+ entry = current_history ();
+
+ if (entry && rl_undo_list)
+ {
+ temp = savestring (the_line);
+ rl_revert_line (1, 0);
+ entry = replace_history_entry (where_history (), the_line, (histdata_t)NULL);
+ _rl_free_history_entry (entry);
+
+ strcpy (the_line, temp);
+ xfree (temp);
+ }
+
+ if (_rl_revert_all_at_newline)
+ _rl_revert_all_lines ();
+
+ /* At any rate, it is highly likely that this line has an undo list. Get
+ rid of it now. */
+ if (rl_undo_list)
+ rl_free_undo_list ();
+
+ /* Disable the meta key, if this terminal has one and we were told to use it.
+ The check whether or not we sent the enable string is in
+ _rl_disable_meta_key(); the flag is set in _rl_enable_meta_key */
+ _rl_disable_meta_key ();
+
+ /* Restore normal cursor, if available. */
+ _rl_set_insert_mode (RL_IM_INSERT, 0);
+
+ return (eof ? (char *)NULL : savestring (the_line));
+}
+
+void
+_rl_internal_char_cleanup ()
+{
+#if defined (VI_MODE)
+ /* In vi mode, when you exit insert mode, the cursor moves back
+ over the previous character. We explicitly check for that here. */
+ if (rl_editing_mode == vi_mode && _rl_keymap == vi_movement_keymap)
+ rl_vi_check ();
+#endif /* VI_MODE */
+
+ if (rl_num_chars_to_read && rl_end >= rl_num_chars_to_read)
+ {
+ (*rl_redisplay_function) ();
+ _rl_want_redisplay = 0;
+ rl_newline (1, '\n');
+ }
+
+ if (rl_done == 0)
+ {
+ (*rl_redisplay_function) ();
+ _rl_want_redisplay = 0;
+ }
+
+ /* If the application writer has told us to erase the entire line if
+ the only character typed was something bound to rl_newline, do so. */
+ if (rl_erase_empty_line && rl_done && rl_last_func == rl_newline &&
+ rl_point == 0 && rl_end == 0)
+ _rl_erase_entire_line ();
+}
+
+STATIC_CALLBACK int
+#if defined (READLINE_CALLBACKS)
+readline_internal_char ()
+#else
+readline_internal_charloop ()
+#endif
+{
+ static int lastc, eof_found;
+ int c, code, lk;
+
+ lastc = EOF;
+ eof_found = 0;
+
+#if !defined (READLINE_CALLBACKS)
+ while (rl_done == 0)
+ {
+#endif
+ lk = _rl_last_command_was_kill;
+
+#if defined (HAVE_POSIX_SIGSETJMP)
+ code = sigsetjmp (_rl_top_level, 0);
+#else
+ code = setjmp (_rl_top_level);
+#endif
+
+ if (code)
+ {
+ (*rl_redisplay_function) ();
+ _rl_want_redisplay = 0;
+ /* If we get here, we're not being called from something dispatched
+ from _rl_callback_read_char(), which sets up its own value of
+ _rl_top_level (saving and restoring the old, of course), so
+ we can just return here. */
+ if (RL_ISSTATE (RL_STATE_CALLBACK))
+ return (0);
+ }
+
+ if (rl_pending_input == 0)
+ {
+ /* Then initialize the argument and number of keys read. */
+ _rl_reset_argument ();
+ rl_key_sequence_length = 0;
+ rl_executing_keyseq[0] = 0;
+ }
+
+ RL_SETSTATE(RL_STATE_READCMD);
+ c = rl_read_key ();
+ RL_UNSETSTATE(RL_STATE_READCMD);
+
+ /* look at input.c:rl_getc() for the circumstances under which this will
+ be returned; punt immediately on read error without converting it to
+ a newline; assume that rl_read_key has already called the signal
+ handler. */
+ if (c == READERR)
+ {
+#if defined (READLINE_CALLBACKS)
+ RL_SETSTATE(RL_STATE_DONE);
+ return (rl_done = 1);
+#else
+ eof_found = 1;
+ break;
+#endif
+ }
+
+ /* EOF typed to a non-blank line is a <NL>. If we want to change this,
+ to force any existing line to be ignored when read(2) reads EOF,
+ for example, this is the place to change. */
+ if (c == EOF && rl_end)
+ {
+ if (RL_SIG_RECEIVED ())
+ {
+ RL_CHECK_SIGNALS ();
+ if (rl_signal_event_hook)
+ (*rl_signal_event_hook) (); /* XXX */
+ }
+
+ /* XXX - reading two consecutive EOFs returns EOF */
+ if (RL_ISSTATE (RL_STATE_TERMPREPPED))
+ {
+ if (lastc == _rl_eof_char || lastc == EOF)
+ rl_end = 0;
+ else
+ c = _rl_eof_char;
+ }
+ else
+ c = NEWLINE;
+ }
+
+ /* The character _rl_eof_char typed to blank line, and not as the
+ previous character is interpreted as EOF. */
+ if (((c == _rl_eof_char && lastc != c) || c == EOF) && rl_end == 0)
+ {
+#if defined (READLINE_CALLBACKS)
+ RL_SETSTATE(RL_STATE_DONE);
+ return (rl_done = 1);
+#else
+ eof_found = 1;
+ break;
+#endif
+ }
+
+ lastc = c;
+ _rl_dispatch ((unsigned char)c, _rl_keymap);
+ RL_CHECK_SIGNALS ();
+
+ /* If there was no change in _rl_last_command_was_kill, then no kill
+ has taken place. Note that if input is pending we are reading
+ a prefix command, so nothing has changed yet. */
+ if (rl_pending_input == 0 && lk == _rl_last_command_was_kill)
+ _rl_last_command_was_kill = 0;
+
+ _rl_internal_char_cleanup ();
+
+#if defined (READLINE_CALLBACKS)
+ return 0;
+#else
+ }
+
+ return (eof_found);
+#endif
+}
+
+#if defined (READLINE_CALLBACKS)
+static int
+readline_internal_charloop ()
+{
+ int eof = 1;
+
+ while (rl_done == 0)
+ eof = readline_internal_char ();
+ return (eof);
+}
+#endif /* READLINE_CALLBACKS */
+
+/* Read a line of input from the global rl_instream, doing output on
+ the global rl_outstream.
+ If rl_prompt is non-null, then that is our prompt. */
+static char *
+readline_internal ()
+{
+ int eof;
+
+ readline_internal_setup ();
+ eof = readline_internal_charloop ();
+ return (readline_internal_teardown (eof));
+}
+
+void
+_rl_init_line_state ()
+{
+ rl_point = rl_end = rl_mark = 0;
+ the_line = rl_line_buffer;
+ the_line[0] = 0;
+}
+
+void
+_rl_set_the_line ()
+{
+ the_line = rl_line_buffer;
+}
+
+#if defined (READLINE_CALLBACKS)
+_rl_keyseq_cxt *
+_rl_keyseq_cxt_alloc ()
+{
+ _rl_keyseq_cxt *cxt;
+
+ cxt = (_rl_keyseq_cxt *)xmalloc (sizeof (_rl_keyseq_cxt));
+
+ cxt->flags = cxt->subseq_arg = cxt->subseq_retval = 0;
+
+ cxt->okey = 0;
+ cxt->ocxt = _rl_kscxt;
+ cxt->childval = 42; /* sentinel value */
+
+ return cxt;
+}
+
+void
+_rl_keyseq_cxt_dispose (cxt)
+ _rl_keyseq_cxt *cxt;
+{
+ xfree (cxt);
+}
+
+void
+_rl_keyseq_chain_dispose ()
+{
+ _rl_keyseq_cxt *cxt;
+
+ while (_rl_kscxt)
+ {
+ cxt = _rl_kscxt;
+ _rl_kscxt = _rl_kscxt->ocxt;
+ _rl_keyseq_cxt_dispose (cxt);
+ }
+}
+#endif
+
+static int
+_rl_subseq_getchar (key)
+ int key;
+{
+ int k;
+
+ if (key == ESC)
+ RL_SETSTATE(RL_STATE_METANEXT);
+ RL_SETSTATE(RL_STATE_MOREINPUT);
+ k = rl_read_key ();
+ RL_UNSETSTATE(RL_STATE_MOREINPUT);
+ if (key == ESC)
+ RL_UNSETSTATE(RL_STATE_METANEXT);
+
+ return k;
+}
+
+#if defined (READLINE_CALLBACKS)
+int
+_rl_dispatch_callback (cxt)
+ _rl_keyseq_cxt *cxt;
+{
+ int nkey, r;
+
+ /* For now */
+ /* The first time this context is used, we want to read input and dispatch
+ on it. When traversing the chain of contexts back `up', we want to use
+ the value from the next context down. We're simulating recursion using
+ a chain of contexts. */
+ if ((cxt->flags & KSEQ_DISPATCHED) == 0)
+ {
+ nkey = _rl_subseq_getchar (cxt->okey);
+ if (nkey < 0)
+ {
+ _rl_abort_internal ();
+ return -1;
+ }
+ r = _rl_dispatch_subseq (nkey, cxt->dmap, cxt->subseq_arg);
+ cxt->flags |= KSEQ_DISPATCHED;
+ }
+ else
+ r = cxt->childval;
+
+ /* For now */
+ if (r != -3) /* don't do this if we indicate there will be other matches */
+ r = _rl_subseq_result (r, cxt->oldmap, cxt->okey, (cxt->flags & KSEQ_SUBSEQ));
+
+ RL_CHECK_SIGNALS ();
+ /* We only treat values < 0 specially to simulate recursion. */
+ if (r >= 0 || (r == -1 && (cxt->flags & KSEQ_SUBSEQ) == 0)) /* success! or failure! */
+ {
+ _rl_keyseq_chain_dispose ();
+ RL_UNSETSTATE (RL_STATE_MULTIKEY);
+ return r;
+ }
+
+ if (r != -3) /* magic value that says we added to the chain */
+ _rl_kscxt = cxt->ocxt;
+ if (_rl_kscxt)
+ _rl_kscxt->childval = r;
+ if (r != -3)
+ _rl_keyseq_cxt_dispose (cxt);
+
+ return r;
+}
+#endif /* READLINE_CALLBACKS */
+
+/* Do the command associated with KEY in MAP.
+ If the associated command is really a keymap, then read
+ another key, and dispatch into that map. */
+int
+_rl_dispatch (key, map)
+ register int key;
+ Keymap map;
+{
+ _rl_dispatching_keymap = map;
+ return _rl_dispatch_subseq (key, map, 0);
+}
+
+int
+_rl_dispatch_subseq (key, map, got_subseq)
+ register int key;
+ Keymap map;
+ int got_subseq;
+{
+ int r, newkey;
+ char *macro;
+ rl_command_func_t *func;
+#if defined (READLINE_CALLBACKS)
+ _rl_keyseq_cxt *cxt;
+#endif
+
+ if (META_CHAR (key) && _rl_convert_meta_chars_to_ascii)
+ {
+ if (map[ESC].type == ISKMAP)
+ {
+ if (RL_ISSTATE (RL_STATE_MACRODEF))
+ _rl_add_macro_char (ESC);
+ RESIZE_KEYSEQ_BUFFER ();
+ rl_executing_keyseq[rl_key_sequence_length++] = ESC;
+ map = FUNCTION_TO_KEYMAP (map, ESC);
+ key = UNMETA (key);
+ return (_rl_dispatch (key, map));
+ }
+ else
+ rl_ding ();
+ return 0;
+ }
+
+ if (RL_ISSTATE (RL_STATE_MACRODEF))
+ _rl_add_macro_char (key);
+
+ r = 0;
+ switch (map[key].type)
+ {
+ case ISFUNC:
+ func = map[key].function;
+ if (func)
+ {
+ /* Special case rl_do_lowercase_version (). */
+ if (func == rl_do_lowercase_version)
+ /* Should we do anything special if key == ANYOTHERKEY? */
+ return (_rl_dispatch (_rl_to_lower (key), map));
+
+ rl_executing_keymap = map;
+ rl_executing_key = key;
+
+ RESIZE_KEYSEQ_BUFFER();
+ rl_executing_keyseq[rl_key_sequence_length++] = key;
+ rl_executing_keyseq[rl_key_sequence_length] = '\0';
+
+ rl_dispatching = 1;
+ RL_SETSTATE(RL_STATE_DISPATCHING);
+ r = (*func) (rl_numeric_arg * rl_arg_sign, key);
+ RL_UNSETSTATE(RL_STATE_DISPATCHING);
+ rl_dispatching = 0;
+
+ /* If we have input pending, then the last command was a prefix
+ command. Don't change the state of rl_last_func. Otherwise,
+ remember the last command executed in this variable. */
+ if (rl_pending_input == 0 && map[key].function != rl_digit_argument)
+ rl_last_func = map[key].function;
+
+ RL_CHECK_SIGNALS ();
+ }
+ else if (map[ANYOTHERKEY].function)
+ {
+ /* OK, there's no function bound in this map, but there is a
+ shadow function that was overridden when the current keymap
+ was created. Return -2 to note that. */
+ if (RL_ISSTATE (RL_STATE_MACROINPUT))
+ _rl_prev_macro_key ();
+ else
+ _rl_unget_char (key);
+ return -2;
+ }
+ else if (got_subseq)
+ {
+ /* Return -1 to note that we're in a subsequence, but we don't
+ have a matching key, nor was one overridden. This means
+ we need to back up the recursion chain and find the last
+ subsequence that is bound to a function. */
+ if (RL_ISSTATE (RL_STATE_MACROINPUT))
+ _rl_prev_macro_key ();
+ else
+ _rl_unget_char (key);
+ return -1;
+ }
+ else
+ {
+#if defined (READLINE_CALLBACKS)
+ RL_UNSETSTATE (RL_STATE_MULTIKEY);
+ _rl_keyseq_chain_dispose ();
+#endif
+ _rl_abort_internal ();
+ return -1;
+ }
+ break;
+
+ case ISKMAP:
+ if (map[key].function != 0)
+ {
+#if defined (VI_MODE)
+ /* The only way this test will be true is if a subsequence has been
+ bound starting with ESC, generally the arrow keys. What we do is
+ check whether there's input in the queue, which there generally
+ will be if an arrow key has been pressed, and, if there's not,
+ just dispatch to (what we assume is) rl_vi_movement_mode right
+ away. This is essentially an input test with a zero timeout (by
+ default) or a timeout determined by the value of `keyseq-timeout' */
+ /* _rl_keyseq_timeout specified in milliseconds; _rl_input_queued
+ takes microseconds, so multiply by 1000 */
+ if (rl_editing_mode == vi_mode && key == ESC && map == vi_insertion_keymap
+ && _rl_input_queued ((_rl_keyseq_timeout > 0) ? _rl_keyseq_timeout*1000 : 0) == 0)
+ return (_rl_dispatch (ANYOTHERKEY, FUNCTION_TO_KEYMAP (map, key)));
+#endif
+
+ RESIZE_KEYSEQ_BUFFER ();
+ rl_executing_keyseq[rl_key_sequence_length++] = key;
+ _rl_dispatching_keymap = FUNCTION_TO_KEYMAP (map, key);
+
+ /* Allocate new context here. Use linked contexts (linked through
+ cxt->ocxt) to simulate recursion */
+#if defined (READLINE_CALLBACKS)
+ if (RL_ISSTATE (RL_STATE_CALLBACK))
+ {
+ /* Return 0 only the first time, to indicate success to
+ _rl_callback_read_char. The rest of the time, we're called
+ from _rl_dispatch_callback, so we return -3 to indicate
+ special handling is necessary. */
+ r = RL_ISSTATE (RL_STATE_MULTIKEY) ? -3 : 0;
+ cxt = _rl_keyseq_cxt_alloc ();
+
+ if (got_subseq)
+ cxt->flags |= KSEQ_SUBSEQ;
+ cxt->okey = key;
+ cxt->oldmap = map;
+ cxt->dmap = _rl_dispatching_keymap;
+ cxt->subseq_arg = got_subseq || cxt->dmap[ANYOTHERKEY].function;
+
+ RL_SETSTATE (RL_STATE_MULTIKEY);
+ _rl_kscxt = cxt;
+
+ return r; /* don't indicate immediate success */
+ }
+#endif
+
+ /* Tentative inter-character timeout for potential multi-key
+ sequences? If no input within timeout, abort sequence and
+ act as if we got non-matching input. */
+ /* _rl_keyseq_timeout specified in milliseconds; _rl_input_queued
+ takes microseconds, so multiply by 1000 */
+ if (_rl_keyseq_timeout > 0 &&
+ (RL_ISSTATE (RL_STATE_INPUTPENDING|RL_STATE_MACROINPUT) == 0) &&
+ _rl_pushed_input_available () == 0 &&
+ _rl_dispatching_keymap[ANYOTHERKEY].function &&
+ _rl_input_queued (_rl_keyseq_timeout*1000) == 0)
+ return (_rl_subseq_result (-2, map, key, got_subseq));
+
+ newkey = _rl_subseq_getchar (key);
+ if (newkey < 0)
+ {
+ _rl_abort_internal ();
+ return -1;
+ }
+
+ r = _rl_dispatch_subseq (newkey, _rl_dispatching_keymap, got_subseq || map[ANYOTHERKEY].function);
+ return _rl_subseq_result (r, map, key, got_subseq);
+ }
+ else
+ {
+ _rl_abort_internal (); /* XXX */
+ return -1;
+ }
+ break;
+
+ case ISMACR:
+ if (map[key].function != 0)
+ {
+ rl_executing_keyseq[rl_key_sequence_length] = '\0';
+ macro = savestring ((char *)map[key].function);
+ _rl_with_macro_input (macro);
+ return 0;
+ }
+ break;
+ }
+#if defined (VI_MODE)
+ if (rl_editing_mode == vi_mode && _rl_keymap == vi_movement_keymap &&
+ key != ANYOTHERKEY &&
+ _rl_dispatching_keymap == vi_movement_keymap &&
+ _rl_vi_textmod_command (key))
+ _rl_vi_set_last (key, rl_numeric_arg, rl_arg_sign);
+#endif
+
+ return (r);
+}
+
+static int
+_rl_subseq_result (r, map, key, got_subseq)
+ int r;
+ Keymap map;
+ int key, got_subseq;
+{
+ Keymap m;
+ int type, nt;
+ rl_command_func_t *func, *nf;
+
+ if (r == -2)
+ /* We didn't match anything, and the keymap we're indexed into
+ shadowed a function previously bound to that prefix. Call
+ the function. The recursive call to _rl_dispatch_subseq has
+ already taken care of pushing any necessary input back onto
+ the input queue with _rl_unget_char. */
+ {
+ m = _rl_dispatching_keymap;
+ type = m[ANYOTHERKEY].type;
+ func = m[ANYOTHERKEY].function;
+ if (type == ISFUNC && func == rl_do_lowercase_version)
+ r = _rl_dispatch (_rl_to_lower (key), map);
+ else if (type == ISFUNC && func == rl_insert)
+ {
+ /* If the function that was shadowed was self-insert, we
+ somehow need a keymap with map[key].func == self-insert.
+ Let's use this one. */
+ nt = m[key].type;
+ nf = m[key].function;
+
+ m[key].type = type;
+ m[key].function = func;
+ r = _rl_dispatch (key, m);
+ m[key].type = nt;
+ m[key].function = nf;
+ }
+ else
+ r = _rl_dispatch (ANYOTHERKEY, m);
+ }
+ else if (r && map[ANYOTHERKEY].function)
+ {
+ /* We didn't match (r is probably -1), so return something to
+ tell the caller that it should try ANYOTHERKEY for an
+ overridden function. */
+ if (RL_ISSTATE (RL_STATE_MACROINPUT))
+ _rl_prev_macro_key ();
+ else
+ _rl_unget_char (key);
+ _rl_dispatching_keymap = map;
+ return -2;
+ }
+ else if (r && got_subseq)
+ {
+ /* OK, back up the chain. */
+ if (RL_ISSTATE (RL_STATE_MACROINPUT))
+ _rl_prev_macro_key ();
+ else
+ _rl_unget_char (key);
+ _rl_dispatching_keymap = map;
+ return -1;
+ }
+
+ return r;
+}
+
+/* **************************************************************** */
+/* */
+/* Initializations */
+/* */
+/* **************************************************************** */
+
+/* Initialize readline (and terminal if not already). */
+int
+rl_initialize ()
+{
+ /* If we have never been called before, initialize the
+ terminal and data structures. */
+ if (!rl_initialized)
+ {
+ RL_SETSTATE(RL_STATE_INITIALIZING);
+ readline_initialize_everything ();
+ RL_UNSETSTATE(RL_STATE_INITIALIZING);
+ rl_initialized++;
+ RL_SETSTATE(RL_STATE_INITIALIZED);
+ }
+
+ /* Initialize the current line information. */
+ _rl_init_line_state ();
+
+ /* We aren't done yet. We haven't even gotten started yet! */
+ rl_done = 0;
+ RL_UNSETSTATE(RL_STATE_DONE);
+
+ /* Tell the history routines what is going on. */
+ _rl_start_using_history ();
+
+ /* Make the display buffer match the state of the line. */
+ rl_reset_line_state ();
+
+ /* No such function typed yet. */
+ rl_last_func = (rl_command_func_t *)NULL;
+
+ /* Parsing of key-bindings begins in an enabled state. */
+ _rl_parsing_conditionalized_out = 0;
+
+#if defined (VI_MODE)
+ if (rl_editing_mode == vi_mode)
+ _rl_vi_initialize_line ();
+#endif
+
+ /* Each line starts in insert mode (the default). */
+ _rl_set_insert_mode (RL_IM_DEFAULT, 1);
+
+ return 0;
+}
+
+#if 0
+#if defined (__EMX__)
+static void
+_emx_build_environ ()
+{
+ TIB *tibp;
+ PIB *pibp;
+ char *t, **tp;
+ int c;
+
+ DosGetInfoBlocks (&tibp, &pibp);
+ t = pibp->pib_pchenv;
+ for (c = 1; *t; c++)
+ t += strlen (t) + 1;
+ tp = environ = (char **)xmalloc ((c + 1) * sizeof (char *));
+ t = pibp->pib_pchenv;
+ while (*t)
+ {
+ *tp++ = t;
+ t += strlen (t) + 1;
+ }
+ *tp = 0;
+}
+#endif /* __EMX__ */
+#endif
+
+/* Initialize the entire state of the world. */
+static void
+readline_initialize_everything ()
+{
+#if 0
+#if defined (__EMX__)
+ if (environ == 0)
+ _emx_build_environ ();
+#endif
+#endif
+
+#if 0
+ /* Find out if we are running in Emacs -- UNUSED. */
+ running_in_emacs = sh_get_env_value ("EMACS") != (char *)0;
+#endif
+
+ /* Set up input and output if they are not already set up. */
+ if (!rl_instream)
+ rl_instream = stdin;
+
+ if (!rl_outstream)
+ rl_outstream = stdout;
+
+ /* Bind _rl_in_stream and _rl_out_stream immediately. These values
+ may change, but they may also be used before readline_internal ()
+ is called. */
+ _rl_in_stream = rl_instream;
+ _rl_out_stream = rl_outstream;
+
+ /* Allocate data structures. */
+ if (rl_line_buffer == 0)
+ rl_line_buffer = (char *)xmalloc (rl_line_buffer_len = DEFAULT_BUFFER_SIZE);
+
+ /* Initialize the terminal interface. */
+ if (rl_terminal_name == 0)
+ rl_terminal_name = sh_get_env_value ("TERM");
+ _rl_init_terminal_io (rl_terminal_name);
+
+ /* Bind tty characters to readline functions. */
+ readline_default_bindings ();
+
+ /* Initialize the function names. */
+ rl_initialize_funmap ();
+
+ /* Decide whether we should automatically go into eight-bit mode. */
+ _rl_init_eightbit ();
+
+ /* Read in the init file. */
+ rl_read_init_file ((char *)NULL);
+
+ /* XXX */
+ if (_rl_horizontal_scroll_mode && _rl_term_autowrap)
+ {
+ _rl_screenwidth--;
+ _rl_screenchars -= _rl_screenheight;
+ }
+
+ /* Override the effect of any `set keymap' assignments in the
+ inputrc file. */
+ rl_set_keymap_from_edit_mode ();
+
+ /* Try to bind a common arrow key prefix, if not already bound. */
+ bind_arrow_keys ();
+
+ /* Bind the bracketed paste prefix assuming that the user will enable
+ it on terminals that support it. */
+ bind_bracketed_paste_prefix ();
+
+ /* If the completion parser's default word break characters haven't
+ been set yet, then do so now. */
+ if (rl_completer_word_break_characters == (char *)NULL)
+ rl_completer_word_break_characters = (char *)rl_basic_word_break_characters;
+
+#if defined (COLOR_SUPPORT)
+ if (_rl_colored_stats || _rl_colored_completion_prefix)
+ _rl_parse_colors ();
+#endif
+
+ rl_executing_keyseq = malloc (_rl_executing_keyseq_size = 16);
+ if (rl_executing_keyseq)
+ rl_executing_keyseq[0] = '\0';
+}
+
+/* If this system allows us to look at the values of the regular
+ input editing characters, then bind them to their readline
+ equivalents, iff the characters are not bound to keymaps. */
+static void
+readline_default_bindings ()
+{
+ if (_rl_bind_stty_chars)
+ rl_tty_set_default_bindings (_rl_keymap);
+}
+
+/* Reset the default bindings for the terminal special characters we're
+ interested in back to rl_insert and read the new ones. */
+static void
+reset_default_bindings ()
+{
+ if (_rl_bind_stty_chars)
+ {
+ rl_tty_unset_default_bindings (_rl_keymap);
+ rl_tty_set_default_bindings (_rl_keymap);
+ }
+}
+
+/* Bind some common arrow key sequences in MAP. */
+static void
+bind_arrow_keys_internal (map)
+ Keymap map;
+{
+ Keymap xkeymap;
+
+ xkeymap = _rl_keymap;
+ _rl_keymap = map;
+
+#if defined (__MSDOS__)
+ rl_bind_keyseq_if_unbound ("\033[0A", rl_get_previous_history);
+ rl_bind_keyseq_if_unbound ("\033[0B", rl_backward_char);
+ rl_bind_keyseq_if_unbound ("\033[0C", rl_forward_char);
+ rl_bind_keyseq_if_unbound ("\033[0D", rl_get_next_history);
+#endif
+
+ rl_bind_keyseq_if_unbound ("\033[A", rl_get_previous_history);
+ rl_bind_keyseq_if_unbound ("\033[B", rl_get_next_history);
+ rl_bind_keyseq_if_unbound ("\033[C", rl_forward_char);
+ rl_bind_keyseq_if_unbound ("\033[D", rl_backward_char);
+ rl_bind_keyseq_if_unbound ("\033[H", rl_beg_of_line);
+ rl_bind_keyseq_if_unbound ("\033[F", rl_end_of_line);
+
+ rl_bind_keyseq_if_unbound ("\033OA", rl_get_previous_history);
+ rl_bind_keyseq_if_unbound ("\033OB", rl_get_next_history);
+ rl_bind_keyseq_if_unbound ("\033OC", rl_forward_char);
+ rl_bind_keyseq_if_unbound ("\033OD", rl_backward_char);
+ rl_bind_keyseq_if_unbound ("\033OH", rl_beg_of_line);
+ rl_bind_keyseq_if_unbound ("\033OF", rl_end_of_line);
+
+#if defined (__MINGW32__)
+ rl_bind_keyseq_if_unbound ("\340H", rl_get_previous_history);
+ rl_bind_keyseq_if_unbound ("\340P", rl_get_next_history);
+ rl_bind_keyseq_if_unbound ("\340M", rl_forward_char);
+ rl_bind_keyseq_if_unbound ("\340K", rl_backward_char);
+ rl_bind_keyseq_if_unbound ("\340G", rl_beg_of_line);
+ rl_bind_keyseq_if_unbound ("\340O", rl_end_of_line);
+ rl_bind_keyseq_if_unbound ("\340S", rl_delete);
+ rl_bind_keyseq_if_unbound ("\340R", rl_overwrite_mode);
+
+ /* These may or may not work because of the embedded NUL. */
+ rl_bind_keyseq_if_unbound ("\\000H", rl_get_previous_history);
+ rl_bind_keyseq_if_unbound ("\\000P", rl_get_next_history);
+ rl_bind_keyseq_if_unbound ("\\000M", rl_forward_char);
+ rl_bind_keyseq_if_unbound ("\\000K", rl_backward_char);
+ rl_bind_keyseq_if_unbound ("\\000G", rl_beg_of_line);
+ rl_bind_keyseq_if_unbound ("\\000O", rl_end_of_line);
+ rl_bind_keyseq_if_unbound ("\\000S", rl_delete);
+ rl_bind_keyseq_if_unbound ("\\000R", rl_overwrite_mode);
+#endif
+
+ _rl_keymap = xkeymap;
+}
+
+/* Try and bind the common arrow key prefixes after giving termcap and
+ the inputrc file a chance to bind them and create `real' keymaps
+ for the arrow key prefix. */
+static void
+bind_arrow_keys ()
+{
+ bind_arrow_keys_internal (emacs_standard_keymap);
+
+#if defined (VI_MODE)
+ bind_arrow_keys_internal (vi_movement_keymap);
+ /* Unbind vi_movement_keymap[ESC] to allow users to repeatedly hit ESC
+ in vi command mode while still allowing the arrow keys to work. */
+ if (vi_movement_keymap[ESC].type == ISKMAP)
+ rl_bind_keyseq_in_map ("\033", (rl_command_func_t *)NULL, vi_movement_keymap);
+ bind_arrow_keys_internal (vi_insertion_keymap);
+#endif
+}
+
+static void
+bind_bracketed_paste_prefix ()
+{
+ Keymap xkeymap;
+
+ xkeymap = _rl_keymap;
+
+ _rl_keymap = emacs_standard_keymap;
+ rl_bind_keyseq_if_unbound (BRACK_PASTE_PREF, rl_bracketed_paste_begin);
+
+ _rl_keymap = vi_insertion_keymap;
+ rl_bind_keyseq_if_unbound (BRACK_PASTE_PREF, rl_bracketed_paste_begin);
+
+ _rl_keymap = xkeymap;
+}
+
+/* **************************************************************** */
+/* */
+/* Saving and Restoring Readline's state */
+/* */
+/* **************************************************************** */
+
+int
+rl_save_state (sp)
+ struct readline_state *sp;
+{
+ if (sp == 0)
+ return -1;
+
+ sp->point = rl_point;
+ sp->end = rl_end;
+ sp->mark = rl_mark;
+ sp->buffer = rl_line_buffer;
+ sp->buflen = rl_line_buffer_len;
+ sp->ul = rl_undo_list;
+ sp->prompt = rl_prompt;
+
+ sp->rlstate = rl_readline_state;
+ sp->done = rl_done;
+ sp->kmap = _rl_keymap;
+
+ sp->lastfunc = rl_last_func;
+ sp->insmode = rl_insert_mode;
+ sp->edmode = rl_editing_mode;
+ sp->kseq = rl_executing_keyseq;
+ sp->kseqlen = rl_key_sequence_length;
+ sp->inf = rl_instream;
+ sp->outf = rl_outstream;
+ sp->pendingin = rl_pending_input;
+ sp->macro = rl_executing_macro;
+
+ sp->catchsigs = rl_catch_signals;
+ sp->catchsigwinch = rl_catch_sigwinch;
+
+ sp->entryfunc = rl_completion_entry_function;
+ sp->menuentryfunc = rl_menu_completion_entry_function;
+ sp->ignorefunc = rl_ignore_some_completions_function;
+ sp->attemptfunc = rl_attempted_completion_function;
+ sp->wordbreakchars = rl_completer_word_break_characters;
+
+ return (0);
+}
+
+int
+rl_restore_state (sp)
+ struct readline_state *sp;
+{
+ if (sp == 0)
+ return -1;
+
+ rl_point = sp->point;
+ rl_end = sp->end;
+ rl_mark = sp->mark;
+ the_line = rl_line_buffer = sp->buffer;
+ rl_line_buffer_len = sp->buflen;
+ rl_undo_list = sp->ul;
+ rl_prompt = sp->prompt;
+
+ rl_readline_state = sp->rlstate;
+ rl_done = sp->done;
+ _rl_keymap = sp->kmap;
+
+ rl_last_func = sp->lastfunc;
+ rl_insert_mode = sp->insmode;
+ rl_editing_mode = sp->edmode;
+ rl_executing_keyseq = sp->kseq;
+ rl_key_sequence_length = sp->kseqlen;
+ rl_instream = sp->inf;
+ rl_outstream = sp->outf;
+ rl_pending_input = sp->pendingin;
+ rl_executing_macro = sp->macro;
+
+ rl_catch_signals = sp->catchsigs;
+ rl_catch_sigwinch = sp->catchsigwinch;
+
+ rl_completion_entry_function = sp->entryfunc;
+ rl_menu_completion_entry_function = sp->menuentryfunc;
+ rl_ignore_some_completions_function = sp->ignorefunc;
+ rl_attempted_completion_function = sp->attemptfunc;
+ rl_completer_word_break_characters = sp->wordbreakchars;
+
+ return (0);
+}
--- /dev/null
+/* rlconf.h -- readline configuration definitions */
+
+/* Copyright (C) 1992-2012 Free Software Foundation, Inc.
+
+ This file is part of the GNU Readline Library (Readline), a library
+ for reading lines of text with interactive input and history editing.
+
+ Readline is free software: you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation, either version 3 of the License, or
+ (at your option) any later version.
+
+ Readline is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with Readline. If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#if !defined (_RLCONF_H_)
+#define _RLCONF_H_
+
+/* Define this if you want the vi-mode editing available. */
+#define VI_MODE
+
+/* Define this to get an indication of file type when listing completions. */
+#define VISIBLE_STATS
+
+/* Define this to get support for colors when listing completions and in
+ other places. */
+#define COLOR_SUPPORT
+
+/* This definition is needed by readline.c, rltty.c, and signals.c. */
+/* If on, then readline handles signals in a way that doesn't suck. */
+#define HANDLE_SIGNALS
+
+/* Ugly but working hack for binding prefix meta. */
+#define PREFIX_META_HACK
+
+/* The next-to-last-ditch effort file name for a user-specific init file. */
+#define DEFAULT_INPUTRC "~/.inputrc"
+
+/* The ultimate last-ditch filenname for an init file -- system-wide. */
+#define SYS_INPUTRC "/etc/inputrc"
+
+/* If defined, expand tabs to spaces. */
+#define DISPLAY_TABS
+
+/* If defined, use the terminal escape sequence to move the cursor forward
+ over a character when updating the line rather than rewriting it. */
+/* #define HACK_TERMCAP_MOTION */
+
+/* The string inserted by the `insert comment' command. */
+#define RL_COMMENT_BEGIN_DEFAULT "#"
+
+/* Define this if you want code that allows readline to be used in an
+ X `callback' style. */
+#ifndef SHELL
+#define READLINE_CALLBACKS
+#endif
+
+/* Define this if you want the cursor to indicate insert or overwrite mode. */
+/* #define CURSOR_MODE */
+
+/* Define this if you want to enable code that talks to the Linux kernel
+ tty auditing system. */
+#define ENABLE_TTY_AUDIT_SUPPORT
+
+/* Defaults for the various editing mode indicators, inserted at the beginning
+ of the last (maybe only) line of the prompt if show-mode-in-prompt is on */
+#define RL_EMACS_MODESTR_DEFAULT "@"
+#define RL_EMACS_MODESTR_DEFLEN 1
+
+#define RL_VI_INS_MODESTR_DEFAULT "(ins)"
+#define RL_VI_INS_MODESTR_DEFLEN 5
+#define RL_VI_CMD_MODESTR_DEFAULT "(cmd)"
+#define RL_VI_CMD_MODESTR_DEFLEN 5
+
+#endif /* _RLCONF_H_ */
pathphys.o: pathphys.c
rename.o: rename.c
setlinebuf.o: setlinebuf.c
+shmatch.o: shmatch.c
shmbchar.o: shmbchar.c
shquote.o: shquote.c
shtty.o: shtty.c
pathphys.o: ${BUILD_DIR}/config.h
rename.o: ${BUILD_DIR}/config.h
setlinebuf.o: ${BUILD_DIR}/config.h
-shmbchare.o: ${BUILD_DIR}/config.h
+shmatch.o: ${BUILD_DIR}/config.h
+shmbchar.o: ${BUILD_DIR}/config.h
shquote.o: ${BUILD_DIR}/config.h
shtty.o: ${BUILD_DIR}/config.h
snprintf.o: ${BUILD_DIR}/config.h
eaccess.o: ${BUILD_DIR}/pathnames.h ${topdir}/externs.h
#eaccess.o: ${BUILD_DIR}/version.h
+shmatch.o: ${BASHINCDIR}/stdc.h ${topdir}/bashansi.h
+shmatch.o: ${BASHINCDIR}/ansi_stdlib.h ${topdir}/xmalloc.h
+shmatch.o: ${topdir}/shell.h ${topdir}/syntax.h ${topdir}/bashjmp.h ${BASHINCDIR}/posixjmp.h
+shmatch.o: ${topdir}/command.h ${BASHINCDIR}/stdc.h ${topdir}/error.h
+shmatch.o: ${topdir}/general.h ${topdir}/bashtypes.h ${topdir}/variables.h ${topdir}/conftypes.h
+shmatch.o: ${topdir}/array.h ${topdir}/hashlib.h ${topdir}/quit.h
+shmatch.o: ${topdir}/unwind_prot.h ${topdir}/dispose_cmd.h
+shmatch.o: ${topdir}/make_cmd.h ${topdir}/subst.h ${topdir}/sig.h
+shmatch.o: ${BUILD_DIR}/pathnames.h ${topdir}/externs.h
+
shquote.o: ${BASHINCDIR}/stdc.h ${topdir}/bashansi.h
shquote.o: ${BASHINCDIR}/ansi_stdlib.h ${topdir}/xmalloc.h
int line_len;
unsigned char c;
- if (!current_readline_line)
+ if (current_readline_line == 0)
{
- if (!bash_readline_initialized)
+ if (bash_readline_initialized == 0)
initialize_readline ();
#if defined (JOB_CONTROL)
f &= ~W_ASSNGLOBAL;
fprintf (stderr, "W_ASSNGLOBAL%s", f ? "|" : "");
}
- if (f & W_ASSIGNINT)
- {
- f &= ~W_ASSIGNINT;
- fprintf (stderr, "W_ASSIGNINT%s", f ? "|" : "");
- }
if (f & W_COMPASSIGN)
{
f &= ~W_COMPASSIGN;
if ((tlist->word->flags & (W_COMPASSIGN|W_ASSIGNARG)) == (W_COMPASSIGN|W_ASSIGNARG))
{
int t;
- char opts[8], opti;
+ char opts[16], opti;
opti = 0;
if (tlist->word->flags & (W_ASSIGNASSOC|W_ASSNGLOBAL|W_ASSIGNARRAY))
else if (tlist->word->flags & W_ASSNGLOBAL)
opts[opti++] = 'g';
-#if 0
- /* If we have special handling note the integer attribute */
- if (opti > 0 && (tlist->word->flags & W_ASSIGNINT))
- opts[opti++] = 'i';
-#endif
+ /* If we have special handling note the integer attribute and others
+ that transform the value upon assignment. What we do is take all
+ of the option arguments and scan through them looking for options
+ that cause such transformations, and add them to the `opts' array. */
+/* if (opti > 0) */
+ {
+ char omap[128];
+ int oind;
+ WORD_LIST *l;
+
+ memset (omap, '\0', sizeof (omap));
+ for (l = orig_list->next; l != tlist; l = l->next)
+ {
+ if (l->word->word[0] != '-')
+ break; /* non-option argument */
+ if (l->word->word[0] == '-' && l->word->word[1] == '-' && l->word->word[2] == 0)
+ break; /* -- signals end of options */
+ for (oind = 1; l->word->word[oind]; oind++)
+ switch (l->word->word[oind])
+ {
+ case 'i':
+ case 'l':
+ case 'u':
+ case 'c':
+ omap[l->word->word[oind]] = 1;
+ if (opti == 0)
+ opts[opti++] = '-';
+ break;
+ default:
+ break;
+ }
+ }
+
+ for (oind = 0; oind < sizeof (omap); oind++)
+ if (omap[oind])
+ opts[opti++] = oind;
+ }
opts[opti] = '\0';
if (opti > 0)
-BUILD_DIR=/usr/local/build/bash/bash-current
+BUILD_DIR=/usr/local/build/chet/bash/bash-current
THIS_SH=$BUILD_DIR/bash
PATH=$PATH:$BUILD_DIR
--- /dev/null
+:; ./shx
+
+sh:
+<&$fd ok
+nlbq Mon Aug 3 02:45:00 EDT 1992
+bang geoff
+quote 712824302
+setbq defmsgid=<1992Aug3.024502.6176@host>
+bgwait sleep done... wait 6187
+
+
+bash:
+<&$fd ok
+nlbq Mon Aug 3 02:45:09 EDT 1992
+bang geoff
+quote 712824311
+setbq defmsgid=<1992Aug3.024512.6212@host>
+bgwait sleep done... wait 6223
+
+
+ash:
+<&$fd shx1: 4: Syntax error: Bad fd number
+nlbq Mon Aug 3 02:45:19 EDT 1992
+bang geoff
+quote getdate: `"now"' not a valid date
+
+setbq defmsgid=<1992Aug3.` echo 024521
+bgwait sleep done... wait 6241
+
+
+ksh:
+<&$fd ok
+nlbq ./shx: 6248 Memory fault - core dumped
+bang geoff
+quote getdate: `"now"' not a valid date
+
+setbq defmsgid=<1992Aug3.024530.6257@host>
+bgwait no such job: 6265
+wait 6265
+sleep done...
+
+zsh:
+<&$fd ok
+nlbq Mon Aug 3 02:45:36 EDT 1992
+bang shx3: event not found: /s/ [4]
+quote 712824337
+setbq defmsgid=<..6290@host>
+bgwait shx7: unmatched " [9]
+sleep done...
+:;
--- /dev/null
+#! /bin/sh
+for cmd in sh bash ash ksh zsh
+do
+ echo
+ echo $cmd:
+ for demo in shx?
+ do
+ $cmd $demo
+ done
+done
projects / thirdparty / bash.git / commitdiff
