+This document details the changes between this version, bash-5.0-release, and
+the previous version, bash-5.0-rc1.
+
+1. Changes to Bash
+
+a. Tilde expansion isn't performed on indexed array subscripts, even for
+ backwards compatibility.
+
+b. The shell doesn't exit in posix mode if the eval builtin gets a parse
+ error when run by the command builtin.
+
+c. Fixed a bug that caused a shell comment in an alias to not find the end
+ of the alias properly.
+
+d. Reverted a change from April, 2018 that caused strings containing
+ backslashes to be flagged as glob patterns.
+
+2. Changes to Readline
+
+3. New Features in Bash
+
+4. New Features in Readline
+
+------------------------------------------------------------------------------
+This document details the changes between this version, bash-5.0-rc1, and
+the previous version, bash-5.0-beta2.
+
+1. Changes to Bash
+
+a. Fix to initial word completion detection code.
+
+b. Fixed a bug that caused issues with assignment statements containing ^A in
+ the value assigned when IFS contains ^A.
+
+c. Added a fallback to fnmatch() when strcoll can't correctly deal with
+ bracket expression character equivalence classes.
+
+d. Fixed a bug that caused $BASH_COMMAND to contain the trap handler command
+ when running a trap handler containing [[ or (( commands.
+
+e. Fixed a bug that caused nameref assignments in the temporary environment
+ to potentially create variables with invalid names.
+
+f. Fixed a bug that caused `local -' to turn off alias expansion in scripts.
+
+g. Fixed a parser issue with a command string containing EOF after an invalid
+ command as an argument to a special builtin not causing a posix-mode shell
+ to exit.
+
+h. Made a slight change to the FNV-1 string hash algorithm used for associative
+ arrays (corrected the initial seed).
+
+2. Changes to Readline
+
+3. New Features in Bash
+
+a. The `select' command now supports command forms without a word list
+ following `in'.
+
+4. New Features in Readline
+
+------------------------------------------------------------------------------
+This document details the changes between this version, bash-5.0-beta2, and
+the previous version, bash-5.0-beta.
+
+1. Changes to Bash
+
+a. Fixed a bug that could cause a seg fault while parsing a subshell command
+ inside a command substitution.
+
+b. Fixed several small memory leaks uncovered by coverity.
+
+c. Fixed a problem with command substitution inside an interactive shell that
+ could cause the parent to receive a SIGHUP.
+
+d. Fixed a problem with using `*' and `@' as subscripts when assigning values
+ to an associative array with assoc_expand_once enabled.
+
+e. Fixed a bug that could cause a huge memory allocation when completing a
+ word beginning with an invalid tilde expansion.
+
+f. Cleaned up some incompatiblities with bash-4.4 when expanding indexed array
+ subscripts used in arithmetic expansions when assoc_expand_once is enabled.
+
+g. The ${parameter@a} expansion will display attributes even if `parameter' is
+ unset.
+
+h. Fixed a bug that caused the output of `set' to cut off some variables before
+ printing the value.
+
+i. Treat a failure to assign a variable when using the ${x:=value} expansion
+ as an expansion error, so non-interactive posix-mode shells exit
+
+j. Fixed a problem when expanding $* in a context where word splitting is not
+ performed when IFS is NULL.
+
+k. Temp files used to store here documents are forced readable, no matter what
+ the user's umask says.
+
+l. Fixed a problem where an interrupted brace expansion could cause the shell
+ to attempt to free an invalid memory location.
+
+m. Make sure to check for any terminating signals after running a trap
+ handler; don't wait until the next time we process traps.
+
+n. Fixed a bug that caused "return" to act like a special builtin with respect
+ to variable assignments even when preceded by "command".
+
+o. POSIX-mode shells now return failure if the cd builtin fails due to the
+ absolute directory name being longer than PATH_MAX, instead of trying
+ again with a relative pathname.
+
+p. Fixed a problem with FUNCNAME occasionally being visible when not executing
+ a shell function.
+
+q. Fixed a problem with the expansions performed on the WORD in the case
+ command.
+
+r. Fixed a slight POSIX compatibility when removing "IFS whitespace" during
+ word splitting and the read builtin.
+
+s. Fixed a problem with expanding an array with subscript `*' when all the
+ elements expand to the empty string, and making sure the expansion honors
+ the `:' specifier.
+
+2. Changes to Readline
+
+a. Fixed a bug with adding multibyte characters to an incremental search string.
+
+b. Fixed a bug with redoing text insertions in vi mode.
+
+c. Fixed a bug with pasting text into an incremental search string if bracketed
+ paste mode is enabled. ESC cannot be one of the incremental search
+ terminator characters for this to work.
+
+d. Fixed a bug with anchored search patterns when performing searches in vi
+ mode.
+
+3. New Features in Bash
+
+a. Associative and indexed arrays now allow subscripts consisting solely of
+ whitespace.
+
+b. `checkwinsize' is now enabled by default.
+
+c. The `localvar_unset' shopt option is now visible and documented.
+
+d. The `progcomp_alias' shopt option is now visible and documented.
+
+e. The signal name processing code now understands `SIGRTMIN+n' all the way
+ up to SIGRTMAX.
+
+f. There is a new `seq' loadable builtin.
+
+g. Trap execution now honors the (internal) max invocations of `eval', since
+ traps are supposed to be executed as if using `eval'.
+
+h. The $_ variable doesn't change when the shell executes a command that forks.
+
+i. The `kill' builtin now supports -sSIGNAME and -nSIGNUM, even though
+ conforming applications aren't supposed to use them.
+
+j. POSIX mode now enables the `shift_verbose' option.
+
+4. New Features in Readline
+
+a. Readline now allows application-defined keymap names; there is a new public
+ function, rl_set_keymap_name(), to do that.
+
+b. The "Insert" keypad key, if available, now puts readline into overwrite
+ mode.
+
+------------------------------------------------------------------------------
+This document details the changes between this version, bash-5.0-beta, and
+the previous version, bash-5.0-alpha.
+
+1. Changes to Bash
+
+a. Fixed a bug that allowed subshells to "inherit" enclosing loops -- this
+ is where POSIX says the subshell is not "enclosed" by the loop.
+
+b. Added more UTF-8-specific versions of multibyte functions, and optimized
+ existing functions if the current locale uses UTF-8 encoding.
+
+c. In POSIX mode, assignments preceding regular builtins should not persist
+ when the builtin completes.
+
+d. Added additional checks to special array assignment (e.g., BASH_ALIASES)
+ so it can't be used to bypass validity checks performed in other places.
+
+e. The `!!' history expansion now refers to the previous history entry as
+ expected, even if used on the second or subsequent line of a multi-line
+ history entry.
+
+f. Fixed a bug that could cause the shell to dereference a NULL pointer if
+ the environment (`environ') is set to NULL.
+
+g. Bash uses slightly better integer overflow handling for brace sequence
+ expansion on systems where ints are 32 bits and intmax_t is 64 bits.
+
+h. Fixed a bug setting attributes for a variable named as an argument to
+ `declare' that also appears as a nameref in the temporary environment.
+
+i. Fixed several bugs that could cause assignments to namerefs to create
+ variables with invalid names.
+
+j. Fixed a bug that could result in the SIGINT handler being set incorrectly
+ in asynchronous subshells.
+
+k. Fixed a bug that could cause `bash -t' to not execute the specified command.
+
+l. Fixed several bugs that caused the shell to operate on the wrong variable
+ when using namerefs with the same name as a global variable in shell
+ functions.
+
+m. Internal changes to how the shell handles variables with invalid names in
+ the initial environment and to prevent variables with invalid names from
+ being added to the environment instead of passing them on to children.
+
+n. Changes to make sure that an expansion that results in a quoted null string
+ is reflected in the expansion, even if the word expands to nothing.
+
+o. Changes to make sure that $* and ${array[*]} (and $@/${array[@]}) expand
+ the same way after the recent changes for POSIX interpretation 888.
+
+p. Saving and restoring the positional parameters at function entry and exit
+ is considerably more efficient; noticeably so when there are large numbers
+ of positional parameters.
+
+q. Fixed a bug that caused `lastpipe' and `pipefail' to return an incorrect
+ status for the pipeline if there was more than one external command in a
+ loop body appearing in the last pipeline element.
+
+r. Fixed a bug that caused value conversion errors with the printf builtin's
+ %u and %f conversion specifications and invalid constants.
+
+2. Changes to Readline
+
+a. Added more UTF-8-specific versions of multibyte functions, and optimized
+ existing functions if the current locale uses UTF-8 encoding.
+
+b. Fixed a problem with bracketed-paste inserting more than one character and
+ interacting with other readline functions.
+
+c. Fixed a bug that caused the history library to attempt to append a history
+ line to a non-existent history entry.
+
+d. If using bracketed paste mode, output a newline after the \r that is the
+ last character of the mode disable string to avoid overwriting output.
+
+e. Fixes to the vi-mode `b', `B', `w', `W', `e', and `E' commands to better
+ handle multibyte characters.
+
+f. Fixed a redisplay problem that caused an extra newline to be generated on
+ accept-line when the line length is exactly the screenwidth.
+
+3. New Features in Bash
+
+a. Bash no longer allows variable assignments preceding a special builtin that
+ changes variable attributes to propagate back to the calling environment
+ unless the compatibility level is 44 or lower.
+
+b. You can set the default value for $HISTSIZE at build time in config-top.h.
+
+c. The `complete' builtin now accepts a -I option that applies the completion
+ to the initial word on the line.
+
+d. The internal bash malloc now uses mmap (if available) to satisfy requests
+ greater than 128K bytes, so free can use mfree to return the pages to the
+ kernel.
+
+e. The shell doesn't automatically set BASH_ARGC and BASH_ARGV at startup
+ unless it's in debugging mode, as the documentation has always said, but
+ will dynamically create them if a script references them at the top level
+ without having enabled debugging mode.
+
+f. The localvar_inherit option will not attempt to inherit a value from a
+ variable of an incompatible type (indexed vs. associative arrays, for
+ example).
+
+g. The `globasciiranges' option is now enabled by default; it can be set to
+ off by default at configuration time.
+
+4. New Features in Readline
+
+a. The history expansion library now understands command and process
+ substitution and extended globbing and allows them to appear anywhere in a
+ word.
+
+b. The history library has a new variable that allows applications to set the
+ initial quoting state, so quoting state can be inherited from a previous
+ line.
+
+------------------------------------------------------------------------------
+This document details the changes between this version, bash-5.0-alpha, and
+the previous version, bash-4.4-release.
+
+1. Changes to Bash
+
+a. Fixed a bug that could cause traps in background jobs to give the terminal
+ to the wrong process group.
+
+b. Fixed a bug that caused `kill -l 0' to print an out-of-range error.
+
+c. Fixed a problem that could result in here-documents being displayed in
+ the wrong order.
+
+d. Fixed a number of out-of-bounds and free memory read errors found via
+ fuzzing.
+
+e. Fixed a subshell inheritance problem that could cause a subshell to wait for
+ the wrong process.
+
+f. Fixed a bug that caused SHLVL to be incremented one too many times when
+ creating subshells.
+
+g. A job dying due to SIGINT can now interrupt sourcing a file in a shell with
+ job control enabled.
+
+h. Fixed a spurious warning about unterminated ${ or $( constructs during
+ word completion.
+
+i. The shell no longer runs traps if a signal arrives while reading command
+ substitution output.
+
+j. Fixed an arithmetic expansion error that could allow ++var++ as valid
+ syntax.
+
+k. Fixed an error that allowed out-of-bounds references to the directory stack.
+
+l. The shell does a better job of saving multi-line history entries with
+ embedded comments.
+
+m. Fixed a bug that could cause quoted bracket expressions in regular expression
+ arguments to `[[' to not match correctly.
+
+n. Fixed a bug that could cause an IFS character in a word to result in an
+ extra '\001' character in the expansion.
+
+o. A trailing backslash in a glob pattern can match a trailing backslash in the
+ string.
+
+p. Fixed a memory leak in the process creation code path when job control is
+ enabled.
+
+q. Fixed a bug that caused `printf' to output broken surrogate pairs for
+ Japanese locales.
+
+r. Fixed a bug that caused a SIGINT generated from `kill' in a dot script to
+ kill an interactive shell.
+
+s. Fixed a bug that could cause the `read' builtin to not fully read a
+ multibyte character.
+
+t. Fixed a bug that could cause identifiers to be evaluated in conditional
+ arithmetic expressions even when evaluation is suppressed.
+
+u. Fixed a bug that could result in command substitution, when executed in a
+ context where word splitting is not performed, to leave a stray '\001'
+ character in the string.
+
+v. Fixed a bug that could cause history expansion to be disabled in a non-
+ interactive shell even if `-o histexpand' is supplied at startup.
+
+w. Fixed a bug that caused `read -N' to strip leading whitespace IFS characters.
+
+x. Fixed a bug that caused spurious tilde expansion in arithmetic expressions.
+
+y. If indirect expansion attempts to indirectly reference through an unset
+ variable, report an error.
+
+z. Added a guard to prevent the shell from looping while receiving an endless
+ stream of SIGTTIN at shell startup.
+
+aa. Fixed a bug with parsing here documents inside a command substitution when
+ looking for the closing delimiter.
+
+bb. Fixed a bug that caused printf to not quote all <blank> characters in the
+ current locale when using the `%q' format specifier.
+
+cc. Fixed a bug with bash's internal buffered I/O system that caused the input
+ pointer to not be reset when read(2) returned an EOF.
+
+dd. Bash now installs its SIGWINCH signal handler with SA_RESTART, so it will
+ not interrupt open/read/write system calls.
+
+ee. The ERR trap now reports line numbers more reliably.
+
+ff. The shell no longer tries to manipulate the terminal process group if a
+ command or process substitution is killed by SIGTERM when job control is
+ enabled.
+
+gg. Fixed a bug that caused extglob patterns to match filenames beginning with
+ a period.
+
+hh. File descriptors open for writing to here documents are no longer available
+ to subshells.
+
+ii. Make sure word completion doesn't perform command or process substitution.
+
+jj. Fixed a bug with parsing $$'...' inside a command substitution.
+
+kk. Fixed a bug that caused bash to remove backslash-newline pairs from the
+ body of a here-document with a quoted delimiter inside a command
+ substitution.
+
+ll. Fixed a bug that could cause the shell to hang when adding a pid to the
+ table of background process exit statuses.
+
+mm. Fixed a bug that could cause 0x01 characters to be doubled in the output
+ of process substitution.
+
+nn. Restricted shells now clear the hash table before making the PATH variable
+ read-only.
+
+oo. There are a number of changes to the expansion of $* and $@ in contexts
+ where word splitting does not occur (quoted and unquoted), with IFS set
+ to NULL or a non-standard value, mostly to deal with the consequences of
+ the behavior defined in Posix interpretation 888.
+
+pp. There are a number of changes to nameref variable handling to avoid
+ creating variables with invalid names.
+
+qq. A non-interactive posix mode shell no longer exits when an assignment
+ statement fails if the assignment is utimately being performed by the
+ `command' builtin.
+
+rr. When using character class names for globbing, don't allow case
+ insensitivity, even if nocaseglob is enabled.
+
+ss. Fixed a bug that allowed some redirections to stay in place if a later
+ redirection failed.
+
+tt. Fixed a bug in how command and process substitutions are recognized within
+ other parameter expansions.
+
+uu. Fixed a bug that caused bash to loop under certain circumstances when
+ performing arithmetic expansion on a variable whose value is an invalid
+ expression.
+
+vv. Fixed a bug that could cause bash to expand aliases inappropriately while
+ parsing compound commands like `case'.
+
+ww. Fixed a bug that could cause `read -N' to fail to read complete multibyte
+ characters, even when the sequences are incomplete or invalid, with or
+ without readline.
+
+xx. Fixed a bug that could cause `case' to fail to match patterns containing
+ 0x01 characters.
+
+yy. Fixed a bug that caused exported functions to contain stray 0x01 characters.
+
+zz. Fixed some inconsistencies with how the history number is handled in the
+ various prompt strings.
+
+aaa. Fixed a bug that could cause a core dump if READLINE_LINE was unset
+ inside a shell function bound to a key sequence with `bind -x'.
+
+bbb. Fixed a bug that could cause bash to not read a token terminator correctly
+ if a command substitution was used inside an arithmetic `for' command.
+
+ccc. Fixed problems that could occur with a fatal arithmetic expansion error
+ in a context (like prompt expansion) where you can't jump back to the
+ top level.
+
+ddd. Expression errors in arithmetic `for' commands are treated more like
+ shell syntax errors.
+
+eee. Fixed a parser synchronization error resulting from a syntax error
+ followed immediately by an EOF.
+
+fff. When executing a shell function, the first line in the function ($LINENO)
+ is line 1 instead of line 0, as Posix requires.
+
+ggg. In Posix mode, bash will canonicalize the value of PWD it inherits from
+ the environment and use that to set its idea of the current directory.
+
+hhh. If LINENO is exported, bash needs to regenerate its value each time it
+ constructs the environment.
+
+iii. Fixed a bug with restoring the SIGINT handler when using `wait -n'.
+
+jjj. Make sure the `coproc' command returns an appropriate status if the NAME
+ argument is invalid.
+
+kkk. Fixed a problem with arithmetic expressions containing array references
+ that contain arithmetic expressions with syntax errors.
+
+lll. The `select' command and help builtin will use $COLUMNS before the window
+ size returned from the kernel as the terminal width.
+
+mmm. `read -n 0' and `read -N 0' now try a zero-length read in an attempt to
+ detect file descriptor errors.
+
+nnn. The `read' builtin now does a better job of acting on signals that don't
+ interrupt read(2).
+
+ooo. Fixed some cases where `printf -v' did not return failure status on a
+ variable assignment error.
+
+ppp. Fixed temporary environment propagation back to the current environment
+ so that it doesn't happen for special builtins run by the `command'
+ builtin.
+
+qqq. Fixed a bug when searching for the end of a here-document delimiter in a
+ command substitution.
+
+rrr. Fixed a bug that could cause `cd ${DIRSTACK[0]}' to fail.
+
+sss. Fixed a bug that could cause reserved words to not be recognized in a
+ for statement without the `in' inside a command substitution.
+
+ttt. Fixed a bug that could cause a double-free in a timed command with an
+ expansion error.
+
+uuu. Fixed a bug that could cause a core dump if a script switches from a UTF-8
+ locale to a different locale after displaying a lone surrogate character.
+
+vvv. Fixed cases where bash prematurely removed FIFOs attached to process
+ substitutions.
+
+www. Fixed a problem with calculating the size of the table that stores exit
+ statuses from background processes when the child process resource limit
+ is very large.
+
+xxx. Fixed a memory leak with functions using `return' when using FIFOs for
+ standard input.
+
+yyy. `wait' without arguments attempts to wait for all active process
+ substitution processes.
+
+zzz. Fixed a bug where an indirect parameter was subjected to word splitting
+ when trying to find the indirected variable name.
+
+aaaa. Fixed a bug that could allow restricted shell users to add commands to
+ the hash table.
+
+bbbb. When using the `!(patlist)' extended globbing operator, a filename
+ beginning with a `.' that doesn't match any of the patterns is not
+ returned as a match if leading dots must be matched explicitly.
+
+cccc. Fixed a bug that could cause line number and source file information for
+ a function definition to be incorrect if there are multiple definitions.
+
+dddd. Fixed a bug that could cause builtins like `readonly' to behave
+ differently when applied to arrays and scalar variables within functions.
+
+eeee. Fixed a bug that could cause alias expansion to add an extra space to
+ a quoted string that begins outside the alias expansion.
+
+ffff. Fixed a bug that could result in unwanted alias expansion after timing
+ the null command.
+
+gggg. Fixed a bug that could cause a core dump if a timestamp in a history
+ file overflowed a time_t.
+
+hhhh. Restricted shells can no longer redirect from /dev/tcp or /dev/udp, since
+ the kernel calls make those file descriptors read-write.
+
+iiii. Fixed a problem with splitting double-quoted words for programmable
+ completion when the double quote immediately follows another word
+ delimiter.
+
+jjjj. Fixed a bug resulting in a use-after-free if two file descriptors share
+ the same input buffer.
+
+kkkk. The error message resulting from ${x:?} and ${x?} now differs depending
+ on whether the variable is null or unset.
+
+llll. In Posix mode, the shell exits if a variable assignment fails and precedes
+ an empty simple command (after expansion).
+
+mmmm. Fixed a timing problem with SIGALRM that could cause the read builtin to
+ drop characters.
+
+nnnn. Added code to deal with kill(2) failing to send the shell a fatal signal
+ due to Linux pid namespace peculiarities.
+
+oooo. Fixed a bug that made \C-@ (NUL) unusable in key sequences used for
+ `bind -x' commands.
+
+pppp. Fixed a bug that could cause SIGINT recursion when running an external
+ command in a trap the shell takes after a command exits due to SIGINT.
+
+qqqq. Make sure the shell turns off job control before running the command-
+ not-found handle, so the command doesn't try to manipulate process
+ groups.
+
+rrrr. Fixed a problem with timing process substitutions that caused the shell
+ to print timing information for the calling command.
+
+ssss. Fixed a bug that caused backquotes in a here-document delimiter to mark
+ the delimiter as quoted (inhibiting expansion of the here-document
+ contents).
+
+tttt. Fixed several problems with 0x01 and 0x177 in case pattern lists and
+ conditional command pattern matches.
+
+uuuu. Fixed a bug that could cause the pattern matching engine to not recognize
+ locale-specific character classes.
+
+vvvv. The auto-configuration now tests for /dev/stdin and /dev/fd independently.
+
+wwww. The `globstar' code now skips over symbolic links to directories,
+ preventing them from being scanned twice.
+
+xxxx. When running `bind -x' commands, bash now sets READLINE_POINT based on
+ the number of characters in the readline line buffer, not the number of
+ bytes.
+
+yyyy. Fixed a problem that could cause recursive trap evaluation of the RETURN
+ trap when using `eval return'.
+
+zzzz. Fixed a bug with expanding 0x01 in an unquoted here-document.
+
+aaaaa. The process substitution code now closes and unlinks FIFOs when the
+ process on the other side exits, in order to prevent SIGPIPE or
+ waiting until a FIFO opened for read has a writer.
+
+bbbbb. Fixed a bug with recursive calls to the parser overwriting the token in
+ an {id}>foo construct.
+
+ccccc. After a Posix discussion, the pattern matching engine just skips over
+ invalid character classes in bracket expressions, instead of matching
+ them like individual characters in the expression.
+
+ddddd. Fixed a posix-mode problem with variable scoping when creating variables
+ from assignment statements preceding special builtins.
+
+eeeee. Fixed a bug that could cause patterns containing backslashes to not be
+ run through the pattern matching engine.
+
+fffff. Fixed a bug that could cause redirections to compound commands to not
+ be `undone' if the file descriptor in the redirection was closed when
+ the redirection was initially processed.
+
+ggggg. Fixed a bug that could cause buffer corruption when using `bind -x' in
+ a command execute as a result of a key binding installed by `bind -x'.
+
+2. Changes to Readline
+
+a. Added a guard to prevent nested macros from causing an infinite expansion
+ loop.
+
+b. Instead of allocating enough history list entries to hold the maximum list
+ size, cap the number allocated initially.
+
+c. Added a strategy to avoid allocating huge amounts of memory if a block of
+ history entries without timestamps occurs after a block with timestamps.
+
+d. Added support for keyboard timeouts when an ESC character is the last
+ character in a macro.
+
+e. There are several performance improvements when in a UTF-8 locale.
+
+f. Readline does a better job of preserving the original set of blocked
+ signals when using pselect() to wait for input.
+
+g. Fixed a bug that caused multibyte characters in macros to be mishandled.
+
+h. Fixed several bugs in the code that calculates line breaks when expanding
+ prompts that span several lines, contain multibyte characters, and contain
+ invisible character seqeuences.
+
+i. Fixed several bugs in cursor positioning when displaying lines with prompts
+ containing invisible characters and multibyte characters.
+
+j. When performing case-insensitive completion, Readline no longer sorts the
+ list of matches unless directed to do so.
+
+k. Fixed a problem with key sequences ending with a backslash.
+
+l. Fixed out-of-bounds and free memory read errors found via fuzzing.
+
+m. Fixed several cases where the mark was set to an invalid value.
+
+n. Fixed a problem with the case-changing operators in the case where the
+ lower and upper case versions of a character do not have the same number
+ of bytes.
+
+o. Handle incremental and non-incremental search character reads returning EOF.
+
+p. Handle the case where a failing readline command at the end of a multi-key
+ sequence could be misinterpreted.
+
+q. The history library now prints a meaningful error message if the history
+ file isn't a regular file.
+
+r. Fixed a problem with vi-mode redo (`.') on a command when trying to replace
+ a multibyte character.
+
+s. The key binding code now attempts to remove a keymap if a key unbinding
+ leaves it empty.
+
+t. Fixed a line-wrapping issue that caused problems for some terminal
+ emulators.
+
+u. If there is a key bound to the tty's VDISCARD special character, readline
+ disables VDISCARD while it is active.
+
+v. Fixed a problem with exiting bracketed paste mode on terminals that assume
+ the bracketed paste mode character sequence contains visible characters.
+
+w. Fixed a bug that could cause a key binding command to refer to an
+ uninitialized variable.
+
+3. New Features in Bash
+
+a. The `wait' builtin can now wait for the last process substitution created.
+
+b. There is an EPOCHSECONDS variable, which expands to the time in seconds
+ since the Unix epoch.
+
+c. There is an EPOCHREALTIME variable, which expands to the time in seconds
+ since the Unix epoch with microsecond granularity.
+
+d. New loadable builtins: rm, stat, fdflags.
+
+e. BASH_ARGV0: a new variable that expands to $0 and sets $0 on assignment.
+
+f. When supplied a numeric argument, the shell-expand-line bindable readline
+ command does not perform quote removal and suppresses command and process
+ substitution.
+
+g. `history -d' understands negative arguments: negative arguments offset from
+ the end of the history list.
+
+h. The `name' argument to the `coproc' reserved word now undergoes word
+ expansion, so unique coprocs can be created in loops.
+
+i. A nameref name resolution loop in a function now resolves to a variable by
+ that name in the global scope.
+
+j. The `wait' builtin now has a `-f' option, which signfies to wait until the
+ specified job or process terminates, instead of waiting until it changes
+ state.
+
+k. There is a define in config-top.h that allows the shell to use a static
+ value for $PATH, overriding whatever is in the environment at startup, for
+ use by the restricted shell.
+
+l. Process substitution does not inherit the `v' option, like command
+ substitution.
+
+m. If a non-interactive shell with job control enabled detects that a foreground
+ job died due to SIGINT, it acts as if it received the SIGINT.
+
+n. The SIGCHLD trap is run once for each exiting child process even if job
+ control is not enabled when the shell is in Posix mode.
+
+o. A new shopt option: localvar_inherit; if set, a local variable inherits the
+ value of a variable with the same name at the nearest preceding scope.
+
+p. `bind -r' now checks whether a key sequence is bound before binding it to
+ NULL, to avoid creating keymaps for a multi-key sequence.
+
+q. A numeric argument to the line editing `operate-and-get-next' command
+ specifies which history entry to use.
+
+r. The positional parameters are now assigned before running the shell startup
+ files, so startup files can use $@.
+
+s. There is a compile-time option that forces the shell to disable the check
+ for an inherited OLDPWD being a directory.
+
+t. The `history' builtin can now delete ranges of history entries using
+ `-d start-end'.
+
+u. The `vi-edit-and-execute-command' bindable readline command now puts readline
+ back in vi insertion mode after executing commands from the edited file.
+
+v. The command completion code now matches aliases and shell function names
+ case-insensitively if the readline completion-ignore-case variable is set.
+
+w. There is a new `assoc_expand_once' shell option that attempts to expand
+ associative array subscripts only once.
+
+x. The shell only sets up BASH_ARGV and BASH_ARGC at startup if extended
+ debugging mode is active. The old behavior of unconditionally setting them
+ is available as part of the shell compatibility options.
+
+y. The `umask' builtin now allows modes and masks greater than octal 777.
+
+z. The `times' builtin now honors the current locale when printing a decimal
+ point.
+
+aa. There is a new (disabled by default, undocumented) shell option to enable
+ and disable sending history to syslog at runtime.
+
+4. New Features in Readline
+
+a. Non-incremental vi-mode search (`N', `n') can search for a shell pattern, as
+ Posix specifies (uses fnmatch(3) if available).
+
+b. There are new `next-screen-line' and `previous-screen-line' bindable
+ commands, which move the cursor to the same column in the next, or previous,
+ physical line, respectively.
+
+c. There are default key bindings for control-arrow-key key combinations.
+
+d. A negative argument (-N) to `quoted-insert' means to insert the next N
+ characters using quoted-insert.
+
+e. New public function: rl_check_signals(), which allows applications to
+ respond to signals that readline catches while waiting for input using
+ a custom read function.
+
+f. There is new support for conditionally testing the readline version in an
+ inputrc file, with a full set of arithmetic comparison operators available.
+
+g. There is a simple variable comparison facility available for use within an
+ inputrc file. Allowable operators are equality and inequality; string
+ variables may be compared to a value; boolean variables must be compared to
+ either `on' or `off'; variable names are separated from the operator by
+ whitespace.
+
+------------------------------------------------------------------------------
+This document details the changes between this version, bash-4.4-release, and
+the previous version, bash-4.4-rc2.
+
+1. Changes to Bash
+
+a. Fixed a bug that could potentially result in a crash due to an integer
+ overflow.
+
+b. Fixed a bug in where commands printed due to `set -x' could be incorrectly
+ quoted if being printed in contexts where they haven't yet been expanded.
+
+c. Fixed several memory leaks.
+
+d. Fixed a bug that could potentially cause the terminal attributes to be
+ set incorrectly by a command run from a programmable completion.
+
+e. Fixed several potential buffer overflow issues in the word expansion code.
+
+2. Changes to Readline
+
+3. New Features in Bash
+
+4. New Features in Readline
+------------------------------------------------------------------------------
+This document details the changes between this version, bash-4.4-rc2, and
+the previous version, bash-4.4-beta2.
+
+1. Changes to Bash
+
+a. Fixed an out-of-bounds read in the redirection operator completion code.
+
+b. Fixed execution context so `until continue' doesn't disable execution for
+ subsequent commands.
+
+c. Fixed trap handling code so traps don't inherit a command's temporary
+ environment.
+
+d. Fixed a bug that resulted in incorrect line numbers when a function is
+ defined as part of another function's execution.
+
+e. Fixed a bug in the expansion of ${a[@]} in contexts where word splitting
+ is not performed and $IFS is not the default.
+
+f. Fixed a bug that caused ''"$@" to not expand to an empty argument when
+ there are no positional parameters.
+
+g. Fixed a bug that caused a shell compiled without job control to use the
+ incorrect exit status for builtin commands preceded by a command executed
+ from the file system that causes the shell to call waitpid().
+
+h. Improved word completion for quoted strings containing unterminated command
+ substitutions with embedded double quotes.
+
+2. Changes to Readline
+
+a. Fixed a bug that caused mode strings to be displayed incorrectly if the
+ prompt was shorter than the mode string.
+
+3. New Features in Bash
+
+a. Using ${a[@]} or ${a[*]} with an array without any assigned elements when
+ the nounset option is enabled no longer throws an unbound variable error.
+
+4. New Features in Readline
+
+a. New application-callable function: rl_pending_signal(): returns the signal
+ number of any signal readline has caught but not yet handled.
+
+b. New application-settable variable: rl_persistent_signal_handlers: if set
+ to a non-zero value, readline will enable the readline-6.2 signal handler
+ behavior in callback mode: handlers are installed when
+ rl_callback_handler_install is called and removed removed when a complete
+ line has been read.
+
+------------------------------------------------------------------------------
+This document details the changes between this version, bash-4.4-beta2, and
+the previous version, bash-4.4-rc1.
+
+1. Changes to Bash
+
+a. Fixed a memory leak when processing ${!var[@]}.
+
+b. Fixed a bug that caused subshells to free trap strings associated with
+ inherited signals.
+
+c. Inheriting BASHOPTS from the environment now works to force actions
+ associated with enabling an option, instead of just marking the option
+ as enabled.
+
+d. Fixed a bug that allowed assignments to BASH_CMDS when the shell was in
+ restricted mode.
+
+e. Fixed a bug caused by an accidental omission of part of the original patch
+ for EXECIGNORE.
+
+e. Prompt expansion now quotes the results of the \s, \h, and \H expansions.
+
+f. Fixed a bug that caused parsing errors in command substitutions with
+ consecutive case statements separated by newlines.
+
+g. Updated logic used to decide whether bash is running inside an emacs
+ terminal emulator to work with future emacs versions.
+
+h. Fixed two extended pattern matching bugs caused by premature short-
+ circuiting.
+
+i. Fixed a memory leak in the code that removes duplicate history entries.
+
+j. There are a number of bug fixes to coproc, mapfile, declare, unset,
+ and assignment statements that prevent nameref variables from creating
+ and unsetting variables with invalid names.
+
+k. Fixed a bug that caused variables to be inadvertently marked as both an
+ associative and an indexed array.
+
+l. Fixed a bug that caused `bash -c' to not run a trap specified in the
+ command string.
+
+j. There are a number of bug fixes to coproc, mapfile, declare, and assignment
+ statements that prevent nameref variables from overwriting or modifying
+ attributes of readonly variables.
+
+k. Fixed a bug that caused command substitution to attempt to set the
+ terminal's process group incorrectly.
+
+l. Fixed a bug that could cause prompt string expansion to display error
+ messages when the `nounset' shell option is set.
+
+m. Fixed a bug that caused "$@" to not expand to an empty string under the
+ circumstances when Posix says it should ("${@-${@-$@}}").
+
+n. Fixed several bugs caused by referencing nameref variables whose values
+ are names of unset variables (or names that are valid for referencing
+ but not assignment), including creating variables in the temporary
+ environment.
+
+o. Function tracing and error tracing are disabled if --debugger is supplied
+ at startup but the shell can't find the debugger start file.
+
+p. Fixed a bug when IFS is used as the control variable in a for statement.
+
+q. Fixed a bug with SIGINT received by a command substitution in an interactive
+ shell.
+
+r. The checks for nameref variable self-references are more thorough.
+
+s. Fixed several bugs with multi-line aliases.
+
+t. Fixed `test' to handle the four-argument case where $1 == '(' and
+ $4 == ')'.
+
+u. Fixed a bug in the expansion of $* in the cases where word splitting is
+ not performed.
+
+v. Fixed a bug in execution of case statements where IFS includes the
+ pattern matching characters.
+
+2. Changes to Readline
+
+a. When refreshing the line as the result of a key sequence, Readline attempts
+ to redraw only the last line of a multiline prompt.
+
+b. Fixed an issue that caused completion of git commands to display
+ incorrectly when using colored-completion-prefix.
+
+c. Fixed several redisplay bugs having to do with multibyte characters and
+ invisible characters in prompt strings.
+
+3. New Features in Bash
+
+a. Value conversions (arithmetic expansions, case modification, etc.) now
+ happen when assigning elements of an array using compound assignment.
+
+b. There is a new option settable in config-top.h that makes multiple
+ directory arguments to `cd' a fatal error.
+
+c. Bash now uses mktemp() when creating internal temporary files; it produces
+ a warning at build time on many Linux systems.
+
+4. New Features in Readline
+
+a. The default binding for ^W in vi mode now uses word boundaries specified
+ by Posix (vi-unix-word-rubout is bindable command name).
+
+b. rl_clear_visible_line: new application-callable function; clears all
+ screen lines occupied by the current visible readline line.
+
+c. rl_tty_set_echoing: application-callable function that controls whether
+ or not readline thinks it is echoing terminal output.
+
+d. Handle >| and strings of digits preceding and following redirection
+ specifications as single tokens when tokenizing the line for history
+ expansion.
+
+e. Fixed a bug with displaying completions when the prefix display length
+ is greater than the length of the completions to be displayed.
+
+f. The :p history modifier now applies to the entire line, so any expansion
+ specifying :p causes the line to be printed instead of expanded.
+
+------------------------------------------------------------------------------
+This document details the changes between this version, bash-4.4-rc1, and
+the previous version, bash-4.4-beta.
+
+1. Changes to Bash
+
+a. Fixed several problems with bash completion not special-casing bash syntax
+ constructs.
+
+b. Fixed a bug that caused the mapfile builtin to not create array variables
+ when a variable of the same name appears in the temporary environment.
+
+c. Fixed a bug that caused prompt expansion to loop when PS1 contained a
+ syntax error.
+
+d. Fixed a bug that caused the ${array[@]@A} expansion to split the results
+ even when double-quoted.
+
+e. There is a new implementation of the code that saves the last CHILD_MAX
+ exited background pids so their status can be queried later.
+
+f. Bash-4.4 can now be configured and built on very old versions of Solaris 2.
+
+g. Fixed problems with --help support for several builtins.
+
+h. Fixed values added to BASH_SOURCE and BASH_LINENO for functions inherited
+ from the environment.
+
+i. Fixed a bug that caused background processes run from non-interactive shells
+ with job control enabled to place the terminal in the wrong process group
+ under certain circumstances.
+
+j. Fixed a bug that caused `fc' to return an incorrect exit status when
+ executing commands from the history list.
+
+k. Fixed a bug that caused the shell to exit when a process substitution
+ received a SIGINT when run in certain terminal emulators.
+
+l. EXECIGNORE now honors the setting of `extglob' when attempting to match
+ executable names.
+
+m. Fixed a bug where `return' used the wrong exit status when executed in a
+ DEBUG trap.
+
+n. Fixed a bug that caused a command containing a here-document and an escaped
+ newline to be stored in the history list incorrectly.
+
+o. Fixed a bug that caused set -e to be honored in cases of builtins invoking
+ other builtins when it should be ignored.
+
+p. Fixed a bug that caused `readonly' and `export' to create local array
+ variables when used within shell functions.
+
+q. Fixed a bug that allowed subshells begun to execute process substitutions
+ to have access to the command's temporary environment.
+
+r. Fixed a bug that could cause the shell to dump core when receiving a
+ SIGCHLD for which a trap has been set while running in posix mode.
+
+s. Fixed a bug that caused bash to not restore BASH_ARGC, BASH_ARGV,
+ BASH_SOURCE, BASH_LINENO, and FUNCNAME if the shell received a SIGINT
+ while reading commands from a file while executing `.'.
+
+t. Fixed a bug that caused the `-o history' option to have no effect when
+ supplied on the command line when starting a new shell.
+
+u. Fixed a bug that caused history expansions occurring in command
+ substitutions to not be performed.
+
+v. Fixed a bug that caused `eval' run in a non-interactive shell to disable
+ history expansion for the remainder of the shell script, even if the script
+ had previously enabled it.
+
+w. Fixed a bug that caused "$@" to not expand to multiple words when IFS is set
+ to the empty string.
+
+x. Fixed a bug that caused process and command substitution to inherit output
+ buffered in the stdio library but not written.
+
+y. Fixed a bug that caused a terminating signal received during `echo' to run
+ an exit trap in a signal handler context.
+
+z. Fixed a bug that caused a builtin command containing a process substitution
+ to return the wrong exit status.
+
+aa. Fixed a bug that caused `()' subshells with piped input to incorrectly
+ redirect the standard input of some of the commands in the subshell from
+ /dev/null.
+
+bb. The history builtin now uses more descriptive error messages for missing or
+ invalid timestamps.
+
+2. Changes to Readline
+
+a. The history file writing functions only attempt to create and use a backup
+ history file if the history file exists and is a regular file.
+
+b. Fixed an out-of-bounds read in readline's internal tilde expansion
+ interface.
+
+c. Fixed several redisplay bugs with prompt strings containing multibyte
+ and non-visible characters whose physical length is longer than the screen
+ width.
+
+d. Fixed a redisplay bug with prompt strings containing invisible characters
+ whose physical length exceeds the screen width and using incremental search.
+
+e. Readline prints more descriptive error messages when it encounters errors
+ while reading an inputrc file.
+
+f. Fixed a bug in the character insertion code that attempts to optimize
+ typeahead when it reads a character that is not bound to self-insert and
+ resets the key sequence state.
+
+3. New Features in Bash
+
+a. BASH_COMPAT and FUNCNEST can be inherited and set from the shell's initial
+ environment.
+
+b. inherit_errexit: a new `shopt' option that, when set, causes command
+ substitutions to inherit the -e option. By default, those subshells disable
+ -e. It's enabled as part of turning on posix mode.
+
+c. New prompt string: PS0. Expanded and displayed by interactive shells after
+ reading a complete command but before executing it.
+
+d. Interactive shells now behave as if SIGTSTP/SIGTTIN/SIGTTOU are set to
+ SIG_DFL when the shell is started, so they are set to SIG_DFL in child
+ processes.
+
+e. Posix-mode shells now allow double quotes to quote the history expansion
+ character.
+
+f. OLDPWD can be inherited from the environment if it names a directory.
+
+g. Shells running as root no longer inherit PS4 from the environment, closing
+ a security hole involving PS4 expansion performing command substitution.
+
+h. If executing an implicit `cd' when the `autocd' option is set, bash will
+ now invoke a function named `cd' if one exists before executing the `cd'
+ builtin.
+
+4. New Features in Readline
+
+a. If an incremental search string has its last character removed with DEL,
+ the resulting empty search string no longer matches the previous line.
+
+b. If readline reads a history file that begins with `#' (or the value of
+ the history comment character) and has enabled history timestamps, the
+ history entries are assumed to be delimited by timestamps. This allows
+ multi-line history entries.
+
+c. Readline now throws an error if it parses a key binding without a
+ terminating `:' or whitespace.
+
+------------------------------------------------------------------------------
+This document details the changes between this version, bash-4.4-beta, and
+the previous version, bash-4.4-alpha.
+
+1. Changes to Bash
+
+a. Fixed two bugs that caused out-of-bounds reads when skipping over assignment
+ statements while finding the word on which to perform programmable
+ completion.
+
+b. Fixed a memory leak in programmable completion.
+
+c. Fixed a bug that could cause the shell to crash when interrupting the
+ wait builtin.
+
+d. Fixed a bug that caused ${!vvv@} to be interpreted as introducing the new
+ `@' operator.
+
+e. Fixed a bug that caused the && and || operators to be incorrectly optimized.
+
+f. The shell now undoes redirections before exiting the shell when the `-e'
+ option is enabled, and a shell function fails.
+
+g. History expansion now skips over the history expansion character in command
+ and process substitution.
+
+h. Fixed a bug that caused stray '\001' characters to be added to the output
+ of `declare -p'.
+
+i. Fixed a memory leak when processing declare commands that perform compound
+ array assignments.
+
+j. Fixed a bug that could cause the shell to crash when reading input from a
+ file and the limit on open file descriptors is high.
+
+k. Fixed a bug that caused the ERR and RETURN traps to be unset if they were
+ set in a shell function but unset previously.
+
+l. Fixed a bug that caused several signals to be ignored if `exec' failed in
+ an interactive shell.
+
+m. A posix-mode non-interactive shell now considers a parameter expansion error
+ to be a fatal error.
+
+n. The `time' command now prints timing statistics for failed commands when
+ the -e option is enabled.
+
+o. Fixed a bug that caused the shell to crash when attempting to indirectly
+ expand a shell variable with an invalid name.
+
+p. Fixed a bug that caused the shell to crash when running a trap containing
+ a process substitution.
+
+q. Bash now prints the keyword `function' before a function with the same name
+ as a reserved word when using `declare -f' to avoid parse errors when
+ reusing the output as input.
+
+r. Fixed a bug that caused the shell to crash when using declare -g to attempt
+ to redefine an existing global indexed array variable as an associative
+ array.
+
+s. Fixed a memory leak that occurred when interrupting brace expansions
+ generating a sequence.
+
+t. Fixed a bug that resulted in alias expansion in redirections.
+
+u. The `declare -a' and `declare -A' commands now print fewer warnings when
+ attempting to create and initialize an array at the same time, but
+ relying on word expansions to construct the compound assignment.
+
+v. The `help' builtin now behaves better in locales where each wide
+ character occupies more than one display column.
+
+w. The `read' builtin no longer has a possible race condition when a timeout
+ occurs.
+
+x. Fixed several expansion problems encountered when IFS="'".
+
+y. Fixed a problem with the expansion of $'\c?'.
+
+z. Bash no longer splits the expansion of here-strings, as the documentation
+ has always said.
+
+aa. Bash now puts `s' in the value of $- if the shell is reading from standard
+ input, as Posix requires.
+
+bb. Fixed a bug that caused the shell to crash if invoked with a NULL
+ environment.
+
+cc. The shell now only trusts an inherited value for $PWD if it begins with a
+ `/'.
+
+dd. Fixed a memory leak when creating local array variables and assigning to
+ them using compound assignment with the `declare' builtin.
+
+ee. Fixed a bug that could cause the shell to crash when processing nested here
+ documents inside a command substitution.
+
+ff. Array keys and values are now displayed using $'...' quoting where
+ appropriate.
+
+gg. Fixed a bug that could cause the shell to crash if the replacement string
+ in pattern substitution was NULL.
+
+hh. Fixed a bug that could cause the shell to crash if a command substitution
+ contained a non-fatal syntax error.
+
+ii. Fixed a bug that could cause the shell to crash if variable indirection
+ resulted in a NULL variable.
+
+jj. Fixed a bug that could cause the shell to crash if a long string contained
+ multiple unterminated parameter expansion constructs.
+
+kk. Improved the code that acts on SIGINT received while waiting for a child
+ process only if the child exits due to SIGINT.
+
+ll. $BASH_SUBSHELL now has more consistent values in asynchronous simple
+ commands.
+
+2. Changes to Readline
+
+a. Colored completion prefixes are now displayed using a different color, less
+ likely to collide with files.
+
+b. Fixed a bug that caused vi-mode character search to misbehave when
+ running in callback mode.
+
+c. Fixed a bug that caused output to be delayed when input is coming from a
+ macro in vi-mode.
+
+d. Fixed a bug that caused the vi-mode `.' command to misbehave when redoing
+ a multi-key key sequence via a macro.
+
+e. Fixed a bug that caused problems with applications that supply their own
+ input function when performing completion.
+
+f. When read returns -1/EIO when attempting to read a key, return an error
+ instead of line termination back to the caller.
+
+g. Updated tty auditing feature based on patch from Red Hat.
+
+h. Fixed a bug that could cause the history library to crash on overflows
+ introduced by malicious editing of timestamps in the history file.
+
+3. New Features in Bash
+
+a. `make install' now installs the example loadable builtins and a set of
+ bash headers to use when developing new loadable builtins.
+
+b. `enable -f' now attempts to call functions named BUILTIN_builtin_load when
+ loading BUILTIN, and BUILTIN_builtin_unload when deleting it. This allows
+ loadable builtins to run initialization and cleanup code.
+
+c. There is a new BASH_LOADABLES_PATH variable containing a list of directories
+ where the `enable -f' command looks for shared objects containing loadable
+ builtins.
+
+d. The `complete_fullquote' option to `shopt' changes filename completion to
+ quote all shell metacharacters in filenames and directory names.
+
+e. The `kill' builtin now has a `-L' option, equivalent to `-l', for
+ compatibility with Linux standalone versions of kill.
+
+4. New Features in Readline
+------------------------------------------------------------------------------
+This document details the changes between this version, bash-4.4-alpha, and
+the previous version, bash-4.3-release.
+
+1. Changes to Bash
+
+a. A bug that caused pipelines to be corrupted while running the DEBUG trap
+ was fixed.
+
+b. A bug that accidentally omitted the `-R' unary operator from `test' was
+ fixed.
+
+c. A bug that could cause the shell to not restore the terminal's process
+ group on shell exit was fixed.
+
+d. Several changes were made to programmable completion to accommodate
+ assumptions made by the bash-completion package.
+
+e. Bash no longer inhibits C-style escape processing ($'...') while performing
+ pattern substitution word expansions.
+
+f. Fixed a bug that caused `return' executed from a trap handler to use the
+ wrong return status when one was not supplied as an argument.
+
+g. In Posix mode, defining a function with the same name as a special
+ builtin is now an error, fatal only when the shell is not interactive.
+
+h. Fixed a bug that caused compound array assignments to discard unset or null
+ variables used as subscripts, thereby making it appear as if the index was
+ not present.
+
+i. Fixed a bug that caused extended glob patterns to incorrectly match
+ filenames with a leading `.'.
+
+j. Fixed a bug involving sign extension when reallocating the input line
+ after a history expansion, causing segmentation faults.
+
+k. Bash now does a better job at identifying syntax errors during word
+ completion and tailoring completion appropriately.
+
+l. Bash now uses the current locale's decimal point in comamnd timing output.
+
+m. Fixed a bug that caused segmentation faults while reading here documents if
+ PS2 contains a command substitution.
+
+n. There are several changes to how $@ is expanded when unquoted but in a
+ context where word splitting is not performed (e.g., on the rhs of an
+ assignment or in a conditional command).
+
+o. Bash now quotes command hash table entries that contain shell metacharacters
+ when displaying hash table contents.
+
+p. Fixed a potential file descriptor leak when dup2() fails while performing a
+ redirection.
+
+q. Fixed a bug that caused directory names evaluated during word completion to
+ be dequoted twice.
+
+r. Fixed several bugs which could result in indirect variable expansion and
+ namerefs creating variables with invalid names or referencing variables
+ set to the empty string.
+
+s. Fixed a bug that caused bash to not expand $0 in word expansions where it
+ should.
+
+t. Fixed a bug that caused bash to perform process substitution if <(
+ appeared inside an arithmetic context.
+
+u. Fixed a bug in extglob pattern parsing that caused slashes in the pattern
+ to be confused as directory names.
+
+v. Fixed several bugs with treatment of invisible variables (variables with
+ attributes that are unset because they have never been assigned values).
+
+w. Fixed a bug that caused the `read' builtin to not clean up readline's
+ state when using the -e and -t options together and the read timed out.
+
+x. Fixed a bug that caused the shell to exit with the wrong (but non-zero)
+ value if a command was not found or was not executable.
+
+y. Fixed a bug that caused the `time' reserved word to not be recognized as
+ such in all contexts where it should have been.
+
+z. Fixed a bug that caused the shell to close process subsitution file
+ descriptors when executing a script without the `#!' leading line.
+
+aa. Fixed a typo that caused the `compat42' shell option to set the wrong
+ compatibility level.
+
+bb. The shell now handles process substitution commands with embedded
+ parentheses the same way as it does when parsing command substitution.
+
+cc. Fixed a bug that caused nested pipelines and the `lastpipe' shell option
+ to produce core dumps.
+
+dd. Fixed a bug that caused patterns containing `*' to match pathnames in cases
+ where slashes must be matched explicitly.
+
+ee. Fixed a problem with patterns containing `:' in colon-separated variables
+ like GLOBIGNORE.
+
+ff. Fixed a bug that caused indirect variable expansion using indexed arrays to
+ always use index 0.
+
+gg. Fixed a parsing problem that caused quoted newlines immediately following a
+ command substitution to be mishandled in certain cases.
+
+hh. Fixed a potential buffer overflow on systems without locale_charset or the
+ bash replacement.
+
+ii. Fixed a bug that caused background processes to modify the terminal's
+ process group under certain circumstances.
+
+jj. Asynchronous commands now always set $? to 0 and are not affected by
+ whether or not the command's exit status is being inverted.
+
+kk. Fixed a problem that caused a line ending with an escaped newline and
+ containingh a prior `eval' to be incorrectly parsed.
+
+ll. Fixed an issue with programmable completion and `!' in extglob patterns
+ used as arguments to `compgen -X'.
+
+mm. Word completion now treats the two-character token `>|' as requiring
+ filename expansion.
+
+nn. Bash no longer expands tildes in $PATH elements while in Posix mode.
+
+oo. Fixed a bug that caused bash to not clean up readline's state, including
+ the terminal settings, if it received a fatal signal while in a readline()
+ call (including `read -e' and `read -s').
+
+pp. Fixed bug that caused importing shell functions from the environment to
+ execute additional commands following the function.
+
+qq. Fixed a bug that caused the parser to return a lookahead character pushed
+ back by a previous call, even when on another line.
+
+rr. Fixed a bug that caused many here-documents or many nested case statements
+ to overflow an internal stack.
+
+ss. Changed the way bash encodes exported functions for inclusion in the
+ environment to avoid name collisions with valid variable names and to
+ indicate that they are exported functions.
+
+tt. Fixed a bug that could result in an invalid memory access when processing
+ a here document delimited by end of file or end of string.
+
+uu. Fixed a bug that could cause an invalid memory access if a command was run
+ before initializing the job control framework.
+
+vv. When in Posix mode, bash prints shell function definitions as Posix
+ specifies them, without the leading `function' keyword.
+
+ww. The variable attribute display builtins no longer display variables with
+ invalid names that were imported from the environment.
+
+xx. Fixed a bug that could allow `break' or `continue' executed from shell
+ functions to affect loops running outside of the function.
+
+yy. Fixed a bug that could cause a restricted shell to attempt to import shell
+ functions from the environment.
+
+zz. The shell now allows double-quoted identifiers in arithmetic expressions.
+
+aaa. Fixed a bug that could allow scalar variables subscripted using [@] in
+ word expansions to be incorrectly quoted.
+
+bbb. The shell now makes sure to ignore SIGTSTP/SIGTTIN/SIGTTOU in child
+ processes if they were ignored at shell startup, even if job control is
+ in effect.
+
+ccc. Fixed a bug that could cause $* to be split on spaces when IFS is set to
+ the empty string.
+
+ddd. Posix says that expanding $* in a pattern context where the expansion is
+ double-quoted should not treat $* as if it were double quoted.
+
+eee. Bash now restores getopts' internal state between calls to getopts even if
+ a shell function declares a local copy of OPTIND.
+
+fff. Fixed a bug that could cause `history -r' or `history -n' to read identical
+ lines from the history file more than once.
+
+ggg. The commands executed by `bind -x' now redisplay at most the final line
+ of a multi-line prompt, and those commands may return 124 to indicate that
+ the entire prompt should be redrawn.
+
+hhh. Fixed a bug that could cause `mapfile' to create variables with invalid
+ names.
+
+iii. The shell only goes into debugging mode when --debugger is supplied if
+ the debugger initialization file is present.
+
+jjj. Fixed a bug that disallowed an assignment to (implicit) subscript 0 of an
+ existing array in a declare command that set the readonly attribute.
+
+kkk. Fixed a bug that inadvertently allowed assignments to FUNCNAME to disable
+ its special status.
+
+lll. Appending to an existing array variable using the compound assignment
+ syntax (var+=(aaa)) should not affect assignments to existing subscripts
+ appearing in the compound assignment.
+
+mmm. Fixed a bug that could cause the shell to crash when a variable with a
+ null value was passed in the temporary environment and the variable's
+ attributes are modified using `declare' while performing a redirection.
+
+nnn. Fixed a bug in printf so that a missing precision specifier after a `.'
+ is treated as 0.
+
+ooo. Fixed a bug that attempted to use the internal command timing to time
+ pipeline components if the pipeline elements are separated by newlines.
+
+ppp. Fixed a bug that caused `declare -al foo=(ONE TWO THREE)' to not lowercase
+ the values on assignment.
+
+qqq. Bash does a better job of determining whether or not files are executable
+ when running on Windows, since the X_OK flag to access(2) is not supported.
+
+rrr. Fixed a bug that caused some of the shell's internal traps (e.g., ERR) to
+ be interrupted (and leave incorrect state) by pending SIGINTs.
+
+sss. Fixed a bug in the bash interface to history expansion to avoid attempting
+ expansion if the history expansion character occurs in a command
+ substitution.
+
+ttt. Fixed a bug that caused the select command to crash if the REPLY variable
+ ends up empty (e.g., if it's made readonly)
+
+uuu. Bash handles backslash-quoting of multibyte characters better when quoting
+ output that is intended to be reused.
+
+vvv. System-specific changes for: Windows, Cygwin.
+
+www. Fixes for upper and lower-casing multibyte characters, some locales have
+ characters whose upper and lowercase versions have different numbers of
+ bytes.
+
+xxx. Fixed a bug that caused the ERR trap in a shell function to have the
+ wrong value for $LINENO.
+
+yyy. Fixed a bug that resulted in incorrect quoting of regexps for the =~
+ operator when an open brace appears without a close brace.
+
+zzz. Fixed a bug in the array unset operation that caused it to attempt to
+ parse embedded single and double quotes.
+
+aaaa. Fixed a bug that caused $* to not expand with the first character of
+ $IFS as a separator in a context where word splitting will not take
+ place.
+
+bbbb. Fixed two bugs that could cause the shell to dereference a null pointer
+ while attempting to print an error message from arithmetic expansion.
+
+cccc. Fixed a bug that resulted in short-circuited evaluation when reading
+ commands from a string ending in an unquoted backslash, or when sourcing
+ a file that ends with an unquoted backslash.
+
+dddd. Fixed a bug that resulted in the no-fork optimization not cleaning up
+ any FIFOs created by process substitution.
+
+eeee. If the -T option is not set, allow the source builtin and shell functions
+ to set a DEBUG trap that persists after the sourced file or function
+ returns, instead of restoring the old (unset) value unconditionally.
+
+ffff. Fixed a bug that caused redirections to not be undone on some syntax
+ errors, e.g., when parsing a command substitution.
+
+gggg. Bash only adds asynchronous commands to the table of background pids
+ whose status it remembers, to avoid it growing too large during scripts
+ that create and reap large numbers of child processes. This means that
+ `wait' no longer works on synchronous jobs, but $? can be used to get
+ the exit status in those cases.
+
+hhhh. Bash now checks whether or not a shell script argument is a directory
+ before trying to open it; Posix says implementations may allow open(2)
+ on a directory.
+
+iiii. Fixed a bug that could cause the shell to set the terminal's process
+ group to a background process group when running as part of a pipeline.
+
+jjjj. Made a few changes to strings to avoid possible potential negative effects
+ caused by malicious translations.
+
+kkkk. Fixed a bug that caused the `unset' builtin to continue to treat its
+ arguments as functions after unsetting a function when invoked with no
+ options.
+
+llll. Fixed a bug that would not replace empty strings using pattern
+ substitution even if the pattern matched the empty string.
+
+mmmm. Fixed a bug with word completion that prevented some characters from
+ being backslash-quoted (backquote, dollar sign).
+
+nnnn. Fixed a bug that prevented a command from the history re-executed by the
+ `fc' builtin from setting verbose mode.
+
+oooo. Fixed a bug that caused the shell to not enable and disable function
+ tracing with changes to the `extdebug' shell option.
+
+pppp. Fixed a bug that caused assignments to nameref variables pointing to
+ unset variables with attributes but no values to create variables with
+ incorrect names.
+
+qqqq. Fixed a bug that caused `unset' on nameref variables (without -n) to
+ unset the wrong variable under certain circumstances.
+
+rrrr. Fixed a bug that caused close braces occurring in brace expansions within
+ command substitutions to incorrectly terminate parameter expansions.
+
+ssss. Fixed a bug that caused `command -p' to temporarily alter $PATH.
+
+tttt. Fixed a bug that caused interactive shells compiled without job control
+ to return incorrect status values for child processes when running a
+ single command that creates enough children to use the entire PID space.
+
+uuuu. `esac' should not be recognized as a reserved word when it appears as the
+ second or later pattern in a case statement pattern list.
+
+vvvv. Fixed a bug that caused the completion code to read past the end of the
+ readline line buffer while skipping assignment statements to find the
+ command name.
+
+wwww. Fixed a bug that caused case statements within loops contained in a
+ command substitution to be parsed incorrectly.
+
+xxxx. Fixed a bug that could cause SIGCHLD handling to be delayed after
+ running `wait' with no arguments and interrupting it with ^C without
+ a trap handler installed.
+
+2. Changes to Readline
+
+a. A bug that caused vi-mode `.' to be unable to redo `c', `d', and `y'
+ commands with modifiers was fixed.
+
+b. Fixed a bug that caused callback mode to dump core when reading a
+ multiple-key sequence (e.g., arrow keys).
+
+c. Fixed a bug that caused the redisplay code to erase some of the line when
+ using horizontal scrolling with incremental search.
+
+d. Readline's input handler now performs signal processing if read(2) is
+ interrupted by SIGALRM or SIGVTALRM.
+
+e. Fixed a problem with revert-all-at-newline freeing freed memory.
+
+f. Clarified the documentation for the history_quotes_inhibit_expansion
+ variable to note that it inhibits scanning for the history comment
+ character and that it only affects double-quoted strings.
+
+g. Fixed an off-by-one error in the prompt printed when performing searches.
+
+h. Use pselect(2), if available, to wait for input before calling read(2), so
+ a SIGWINCH can interrupt it, since it doesn't interrupt read(2).
+
+i. Some memory leaks caused by signals interrupting filename completion have
+ been fixed.
+
+j. Reading EOF twice on a non-empty line causes EOF to be returned, rather
+ than the partial line. This can cause partial lines to be executed on
+ SIGHUP, for example.
+
+k. Fixed a bug concerning deleting multibyte characters from the search
+ string while performing an incremental search.
+
+l. Fixed a bug with tilde expanding directory names in filename completion.
+
+m. Fixed a bug that did not allow binding sequences beginning with a `\'.
+
+n. Fixed a redisplay bug involving incorrect line wrapping when the prompt
+ contains a multibyte character in the last screen column.
+
+o. Fixed a bug that caused history expansion to disregard characters that are
+ documented to delimit a history event specifier without requiring `:'.
+
+p. Fixed a bug that could cause reading past the end of a string when reading
+ the value when binding the set of isearch terminators.
+
+q. Fixed a bug that caused readline commands that depend on knowing which
+ key invoked them to misbehave when dispatching key sequences that are
+ prefixes of other key bindings.
+
+r. Paren matching now works in vi insert mode.
+
+3. New Features in Bash
+
+a. There is now a settable configuration #define that will cause the shell
+ to exit if the shell is running setuid without the -p option and setuid
+ to the real uid fails.
+
+b. Command and process substitutions now turn off the `-v' option when
+ executing, as other shells seem to do.
+
+c. The default value for the `checkhash' shell option may now be set at
+ compile time with a #define.
+
+d. The `mapfile' builtin now has a -d option to use an arbitrary character
+ as the record delimiter, and a -t option to strip the delimiter as
+ supplied with -d.
+
+e. The maximum number of nested recursive calls to `eval' is now settable in
+ config-top.h; the default is no limit.
+
+f. The `-p' option to declare and similar builtins will display attributes for
+ named variables even when those variables have not been assigned values
+ (which are technically unset).
+
+g. The maximum number of nested recursive calls to `source' is now settable
+ in config-top.h; the default is no limit.
+
+h. All builtin commands recognize the `--help' option and print a usage
+ summary.
+
+i. Bash does not allow function names containing `/' and `=' to be exported.
+
+j. The `ulimit' builtin has new -k (kqueues) and -P (pseudoterminals) options.
+
+k. The shell now allows `time ; othercommand' to time null commands.
+
+l. There is a new `--enable-function-import' configuration option to allow
+ importing shell functions from the environment; import is enabled by
+ default.
+
+m. `printf -v var ""' will now set `var' to the empty string, as if `var=""'
+ had been executed.
+
+n. GLOBIGNORE, the pattern substitution word expansion, and programmable
+ completion match filtering now honor the value of the `nocasematch' option.
+
+o. There is a new ${parameter@spec} family of operators to transform the
+ value of `parameter'.
+
+p. Bash no longer attempts to perform compound assignment if a variable on the
+ rhs of an assignment statement argument to `declare' has the form of a
+ compound assignment (e.g., w='(word)' ; declare foo=$w); compound
+ assignments are accepted if the variable was already declared as an array,
+ but with a warning.
+
+q. The declare builtin no longer displays array variables using the compound
+ assignment syntax with quotes; that will generate warnings when re-used as
+ input, and isn't necessary.
+
+r. Executing the rhs of && and || will no longer cause the shell to fork if
+ it's not necessary.
+
+s. The `local' builtin takes a new argument: `-', which will cause it to save
+ the single-letter shell options and restore their previous values at
+ function return.
+
+t. `complete' and `compgen' have a new `-o nosort' option, which forces
+ readline to not sort the completion matches.
+
+u. Bash now allows waiting for the most recent process substitution, since it
+ appears as $!.
+
+v. The `unset' builtin now unsets a scalar variable if it is subscripted with
+ a `0', analogous to the ${var[0]} expansion.
+
+w. `set -i' is no longer valid, as in other shells.
+
+x. BASH_SUBSHELL is now updated for process substitution and group commands
+ in pipelines, and is available with the same value when running any exit
+ trap.
+
+y. Bash now checks $INSIDE_EMACS as well as $EMACS when deciding whether or
+ not bash is being run in a GNU Emacs shell window.
+
+z. Bash now treats SIGINT received when running a non-builtin command in a
+ loop the way it has traditionally treated running a builtin command:
+ running any trap handler and breaking out of the loop.
+
+aa. New variable: EXECIGNORE; a colon-separate list of patterns that will
+ cause matching filenames to be ignored when searching for commands.
+
+bb. Aliases whose value ends in a shell metacharacter now expand in a way to
+ allow them to be `pasted' to the next token, which can potentially change
+ the meaning of a command (e.g., turning `&' into `&&').
+
+4. New Features in Readline
+
+a. The history truncation code now uses the same error recovery mechansim as
+ the history writing code, and restores the old version of the history file
+ on error. The error recovery mechanism handles symlinked history files.
+
+b. There is a new bindable variable, `enable-bracketed-paste', which enables
+ support for a terminal's bracketed paste mode.
+
+c. The editing mode indicators can now be strings and are user-settable
+ (new `emacs-mode-string', `vi-cmd-mode-string' and `vi-ins-mode-string'
+ variables). Mode strings can contain invisible character sequences.
+ Setting mode strings to null strings restores the defaults.
+
+d. Prompt expansion adds the mode string to the last line of a multi-line
+ prompt (one with embedded newlines).
+
+e. There is a new bindable variable, `colored-completion-prefix', which, if
+ set, causes the common prefix of a set of possible completions to be
+ displayed in color.
+
+f. There is a new bindable command `vi-yank-pop', a vi-mode version of emacs-
+ mode yank-pop.
+
+g. The redisplay code underwent several efficiency improvements for multibyte
+ locales.
+
+h. The insert-char function attempts to batch-insert all pending typeahead
+ that maps to self-insert, as long as it is coming from the terminal.
+
+i. rl_callback_sigcleanup: a new application function that can clean up and
+ unset any state set by readline's callback mode. Intended to be used
+ after a signal.
+
+------------------------------------------------------------------------------
+This document details the changes between this version, bash-4.3-release, and
+the previous version, bash-4.3-rc2.
+
+1. Changes to Bash
+
+a. Only Posix-mode shells should exit on an assignment failure in the
+ temporary environment preceding a special builtin. This is how it's been
+ documented.
+
+b. Fixed a bug that caused a failed special builtin to not exit a posix-mode
+ shell if the failing builtin was on the LHS of a && or ||.
+
+c. Changed the handling of unquoted backslashes in regular expressions to be
+ closer to bash-4.2.
+
+d. globstar (**) no longer traverses symbolic links that resolve to
+ directories. This eliminates some duplicate entries.
+
+e. Fixed a bug that caused a SIGCHLD trap handler to not be able to change the
+ SIGCHLD disposition.
+
+f. Fixed a bug that caused a crash when -x was enabled and a command
+ contained a printable multibyte (wide) character.
+
+g. Fixed a bug that caused an interactive shell without line editing enabled
+ to read invalid data after receiving a SIGINT.
+
+h. Fixed a bug that caused command word completion to fail if the directory in
+ $PATH where the completion would be found contained single or double quotes.
+
+i. Fixed a bug that caused a shell with -v enabled to print commands in $()
+ multiple times.
+
+2. Changes to Readline
+
+a. Fixed a bug that caused `undo' to reference freed memory or null pointers.
+
+3. New Features in Bash
+
+a. The [[ -v ]] option now understands array references (foo[1]) and returns
+ success if the referenced element has a value.
+
+------------------------------------------------------------------------------
+This document details the changes between this version, bash-4.3-rc2, and the
+previous version, bash-4.3-rc1.
+
+1. Changes to Bash
+
+a. Fixed a bug that left variables set by printf -v marked as invisible.
+
+b. Fixed an off-by-one error in a job control warning message.
+
+c. Fixed a bug that caused the shell to crash after declaring a nameref variable
+ without a value.
+
+d. Fixed a bug that caused asynchronous commands to not set $? correctly.
+
+e. Fixed a bug that caused out-of-order execution when executing aliases with
+ embedded newlines containing `.' commands.
+
+f. Fixed a bug that caused error messages generated by expansion errors in
+ `for' commands to have the wrong line number.
+
+g. Fixed a bug that caused the `wait' builtin to not be interruptible in an
+ interactive shell with job control enabled.
+
+h. Fixed a bug that caused SIGINT and SIGQUIT to not be trappable in
+ asynchronous subshell commands.
+
+i. Bash now requires that the value assigned to a nameref variable be a valid
+ shell identifier (variable name or array reference).
+
+j. Converting an existing variable to a nameref variable now turns off the
+ -i/-l/-u/-c attributes.
+
+k. Displaying a nameref variable with `declare -p' now displays the nameref
+ variable and its value rather than following the nameref chain.
+
+l. Fixed a problem with interrupt handling that caused a second and subsequent
+ SIGINT to be ignored by interactive shells.
+
+m. Fixed a bug that caused certain positional parameter and array expansions
+ to mishandle (discard) null positional parameters and array elements.
+
+n. The shell no longer blocks receipt of signals while running trap handlers
+ for those signals, and allows most trap handlers to be run recursively
+ (running trap handlers while a trap handler is executing).
+
+o. The shell now handles backslashes in regular expression arguments to the
+ [[ command's =~ operator slightly differently, resulting in more
+ consistent behavior.
+
+2. Changes to Readline
+
+a. Fixed a bug that could cause readline to crash and seg fault attempting to
+ expand an empty history entry.
+
+b. Fixed a bug that caused a bad entry in the $LS_COLORS variable to abort all
+ color processing but leave color enabled.
+
+c. Fixed a bug that caused display problems with multi-line prompts containing
+ invisible characters on multiple lines.
+
+d. Fixed a bug that caused effects made by undoing changes to a history line to
+ be discarded.
+
+3. New Features in Bash
+
+4. New Features in Readline
+
+a. When creating shared libraries on Mac OS X, the pathname written into the
+ library (install_name) no longer includes the minor version number.
+------------------------------------------------------------------------------
+This document details the changes between this version, bash-4.3-rc1, and the
+previous version, bash-4.3-beta2.
+
+1. Changes to Bash
+
+a. Fixed a bug in bash completion that caused a tilde to be expanded even if
+ the `direxpand' option was not enabled.
+
+b. Fixed a potential bug that could cause corrupted input in interactive shells
+ running without line editing and with `ignoreeof' enabled.
+
+c. Fixed a bug that could cause failures when opening pipes back to shells
+ created to run process substitutions.
+
+d. Fixed a bug that caused an assignment to TEXTDOMAIN to require TEXTDOMAINDIR
+ to be set in order to actually change the current text domain.
+
+e. Changed the way redirections are printed to avoid confusion when the target
+ of an output redirection is a process substitution beginning with `>'.
+
+2. Changes to Readline
+
+a. Shared library building is now supported on Mac OS X 10.9 (Darwin 13).
+
+3. New Features in Bash
+
+a. `cd' has a new `-@' option to browse a file's extended attributes on
+ systems that support O_XATTR.
+
+4. New Features in Readline
+
+a. There are additional default key bindings for MinGW32
+
+------------------------------------------------------------------------------
+This document details the changes between this version, bash-4.3-beta2, and the
+previous version, bash-4.3-beta.
+
+1. Changes to Bash
+
+a. Fixed a bug that caused assignment to an unset variable using a negative
+ subscript to result in a segmentation fault.
+
+b. Fixed a bug that caused assignment to a string variable using a negative
+ subscript to use the incorrect index.
+
+c. Fixed a bug that caused some strings to be interpreted as invalid
+ extended globbing expressions when used with the help builtin.
+
+d. Fixed a bug that caused an attempt to trap a signal whose disposition
+ cannot be changed to reference uninitialized memory.
+
+e. Command completion now skips assignment statements preceding a command
+ name and completes the command.
+
+f. Fixed a bug that caused `compgen -f' in a non-interactive shell to dump
+ core under certain circumstances.
+
+g. Fixed a bug that caused the `read -N' to misbehave when the input stream
+ contains 0xff.
+
+2. Changes to Readline
+
+a. Changed message when an incremental search fails to include "failed" in
+ the prompt and display the entire search string instead of just the last
+ matching portion.
+
+b. Fixed a bug that caused an arrow key typed to an incremental search prompt
+ to process the key sequence incorrectly.
+
+c. Additional key bindings for arrow keys on MinGW.
+
+3. New Features in Bash
+
+a. The help builtin now attempts substring matching (as it did through
+ bash-4.2) if exact string matching fails.
+
+b. The fc builtin now interprets -0 as the current command line.
+
+c. Completing directory names containing shell variables now adds a trailing
+ slash if the expanded result is a directory.
+
+4. New Features in Readline
+
+a. rl_change_environment: new application-settable variable that controls
+ whether or not Readline modifies the environment (currently readline
+ modifies only LINES and COLUMNS).
+
+------------------------------------------------------------------------------
+This document details the changes between this version, bash-4.3-beta, and the
+previous version, bash-4.3-alpha.
+
+1. Changes to Bash
+
+a. Fixed a bug in the prompt directory name "trimming" code that caused
+ memory corruption and garbled the results.
+
+b. Fixed a bug that caused single quotes that resulted from $'...' quoting
+ in the replacement portion of a double-quoted ${word/pat/rep} expansion
+ to be treated as quote characters.
+
+c. Fixed a bug that caused assignment statements preceding a command word to
+ result in assignment statements following a declaration command to not be
+ expanded like assignment statements.
+
+d. Fixed a bug with variable search order in the presence of local variables
+ with the same name as variables in the temporary environment supplied to
+ a shell function.
+
+e. Fixed a bug that caused constructs like 1<(2) to be interpreted as process
+ substitutions even in an arithmetic context.
+
+f. Fixed several cases where `invisible' variables (variables with attributes
+ but no values, which are technically unset) were treated incorrectly.
+
+g. Fixed a bug that caused group commands in pipelines that were not the
+ last element to not run the EXIT trap.
+
+h. Fixed a bug that caused `unset -n' to not unset a nameref variable in
+ certain cases.
+
+i. Fixed the nameref circular reference checking to be less strict and only
+ disallow a nameref variable with the same value as its name at the global
+ scope.
+
+j. Fixed a bug that caused trap handlers to be executed recursively,
+ corrupting internal data structures.
+
+k. Fixed a bug that could result in bash not compiling if certain options were
+ not enabled.
+
+l. Fixed a bug that caused the arithmetic expansion code to attempt variable
+ assignments when operator precedence prohibited them.
+
+m. Word expansions like ${foo##bar} now understand indirect variable references.
+
+n. Fixed a bug that caused `declare -fp name' to not display a function
+ definition.
+
+o. Fixed a bug that caused asynchronous child processes to modify the stdin
+ file pointer when bash was using it to read a script, which modified the
+ parent's value as well.
+
+2. Changes to Readline
+
+a. Fixed a bug in vi mode that caused the arrow keys to set the saved last
+ vi-mode command to the wrong value.
+
+b. Fixed a bug that caused double-quoted strings to be scanned incorrectly
+ when being used as the value of a readline variable assignment.
+
+c. Fixed a bug with vi mode that prevented `.' from repeating a command
+ entered on a previous line (command).
+
+d. Fixed a bug that could cause completion to core dump if it was interrupted
+ by a signal.
+
+e. Readline now sends the meta-key enable string to the terminal if the
+ terminal has been successfully initialized.
+
+f. Readline now calls the signal hook after resizing the terminal when it
+ receives a SIGWINCH.
+
+g. Fixed a bug that could cause the history list code to perform an out-of-
+ bounds array reference if the history list is empty.
+
+3. New Features in Bash
+
+a. Shells started to run process substitutions now run any trap set on EXIT.
+
+b. There is now a configure-time option to enable the globasciiranges option
+ by default.
+
+c. The read builtin now checks its first variable argument for validity before
+ trying to read any input.
+
+------------------------------------------------------------------------------
+This document details the changes between this version, bash-4.3-alpha,
+and the previous version, bash-4.2-release.
+
+1. Changes to Bash
+
+a. Fixed several bugs concerning incomplete bracket expressions in filename
+ generation (globbing) patterns.
+
+b. Fixed a bug with single quotes and WORD in ${param op WORD} when running
+ in Posix mode.
+
+c. Fixed a bug that caused the pattern removal and pattern substitution word
+ expansions and case statement word expansion to not match the empty string.
+
+d. Fixed a bug that caused the tzset() function to not work after changing
+ the TZ enviroment variable.
+
+e. Fixed a bug that caused the RHS of an assignment statement to undergo
+ word splitting when it contained an unquoted $@.
+
+f. Fixed bugs that caused the shell to not react to a SIGINT sent while
+ waiting for a child process to exit.
+
+g. Bash doesn't try to run things in a signal handler context when it gets a
+ signal (SIGINT/SIGHUP/etc) while reading input using readline but still
+ be responsive to terminating signals.
+
+h. Fixed a bug that caused bash to go into an infinite loop if a filename
+ to be matched contained an invalid multibyte character.
+
+i. Fixed a bug that caused PS4 to end up being truncated if it is longer
+ than 128 bytes.
+
+j. Fixed a bug that caused brace expansion to not skip over double-quoted
+ command substitution.
+
+k. System-specific updates for: DJGPP, HP/UX, Mac OS X
+
+l. Fixed a bug in displaying commands that caused redirections to be associated
+ with the wrong part of the command.
+
+m. Fixed the coproc cleanup to unset the appropriate shell variables when a
+ coproc terminates.
+
+n. Fixed a bug that caused `fc' to dump core due to incorrect calculation of
+ the last history entry.
+
+o. Added workarounds for FreeBSD's implementation of faccessat/eaccess and
+ `test -x'.
+
+p. Fixed a bug that caused the shell to not match patterns containing
+ control-A.
+
+q. Fixed a bug that could result in doubled error messages when the `printf'
+ builtin got a write error.
+
+r. Fixed a bug that caused the shell to not correctly expand words containing
+ multiple consecutive quoted empty strings (""""""aa).
+
+s. Fixed a bug that caused the shell to not correctly parse multi-line
+ process substitutions containing comments and quoted strings.
+
+t. Fixed a problem with the bash malloc's internal idea of the top of the
+ memory heap that resulted in incorrect decisions to try to reduce the
+ break and give memory back to the kernel.
+
+u. There are changes to the expansions peformed on compound array assignments,
+ in an effort to make foo=( [ind1]=bar [ind2]=baz ) identical to
+ foo[ind1]=bar foo[ind2]=baz.
+
+v. Bash now reports an error if `read -a name' is used when `name' is an
+ existing associative array.
+
+w. Fixed a bug that allowed an attempted assignment to a readonly variable
+ in an arithmetic expression to not return failure.
+
+x. Fixed several bugs that caused completion functions to be invoked even when
+ the cursor was before the first word in the command.
+
+y. Fixed a bug that caused parsing a command substitution to overwrite the
+ parsing state associated with the complete input line.
+
+z. Fixed several bugs with the built-in snprintf replacement and field widths
+ and floating point.
+
+aa. Fixed a bug that caused incorrect offset calculations and input buffer
+ corruption when reading files longer than 2^31 bytes.
+
+bb. Fixed several bugs where bash performed arithmetic evaluation in contexts
+ where evaluation is suppressed.
+
+cc. Fixed a bug that caused bash to close FIFOs used for process substitution
+ too early when a shell function was executing, but protect against using
+ all file descriptors when the shell functions are invoked inside loops.
+
+dd. Added checks for printable (and non-printable) multibyte characters for
+ use in error messages.
+
+ee. Fixed a bug that caused ^O (operate-and-get-next) to not work correctly
+ at the end of the history list.
+
+ff. Fixed a bug that caused command-oriented history to incorrectly combine
+ here documents into one line.
+
+gg. Fixed a bug that caused importing SHELLOPTS from the environment into a
+ Posix-mode shell to print an error message and refuse to parse it.
+
+hh. Fixed a bug that caused the shell to delete an extra history entry when
+ using `history -s'.
+
+ii. Fixed a bug that caused floating-point exceptions and overflow errors
+ for the / and % arithmetic operators when using INTMAX_MIN and -1.
+
+jj. Fixed a bug that caused parsing errors when reading an arithmetic for
+ loop inside a command substitution.
+
+kk. Fixed a bug that caused a readonly function to be unset when unset was
+ called without the -f or -v option.
+
+ll. Fixed several bugs in the code that quotes characters special to regular
+ expressions when used in a quoted string on the RHS of the =~ operator
+ to the [[ command.
+
+mm. Fixed a bug that caused redirections to fail because the file descriptor
+ limit was set to a value less than 10.
+
+nn. Fixed a bug that caused the `read' builtin to execute code in a signal
+ handler context if read timed out.
+
+oo. Fixed a bug that caused extended globbing patterns to not match files
+ beginning with `.' correctly when a `.' was explicitly supplied in the
+ pattern.
+
+pp. Fixed a bug that caused key sequences longer than two characters to not
+ work when used with `bind -x'.
+
+qq. Fixed a bug that resulted in redefined functions having the wrong source
+ file names in BASH_SOURCE.
+
+rr. Fixed a bug that caused the read builtin to assign null strings to variables
+ when using `read -N', which caused core dumps when referenced
+
+ss. Fixed a bug that caused `bash -m script' to not enable job control while
+ running the script.
+
+tt. Fixed a bug that caused `printf -v var' to dump core when used with the
+ %b format code.
+
+uu. Fixed a bug that caused the shell to exit with the wrong status if -e was
+ active and the shell exited on a substitution error.
+
+vv. Fixed a bug that caused the shell to seg fault if an array variable with
+ the same name as an existing associative array was implicitly created by
+ an assignment (declare a[n]=b).
+
+ww. Fixed a bug that caused a redirection to misbehave if the number specified
+ for a file descriptor overflows an intmax_t.
+
+xx. Fixed several bugs with the handling of valid and invalid unicode character
+ values when used with the \u and \U escape sequences to printf and $'...'.
+
+yy. Fixed a bug that caused tildes to not be escaped in expanded filenames,
+ making them subject to later expansion.
+
+zz. When using the pattern substitution word expansion, bash now runs the
+ replacement string through quote removal, since it allows quotes in that
+ string to act as escape characters. This is not backwards compatible, so
+ it can be disabled by setting the bash compatibility mode to 4.2.
+
+aaa. Fixed the rest of the cases where the shell runs non-allowed code in a
+ signal handler context.
+
+bbb. Fixed a bug that caused spurious DEL characters (\177) to appear in
+ double-quoted expansion where the RHS is evaluated to the empty string.
+
+ccc. Fixed a bug that caused the use of the shell's internal random number
+ generator for temporary file names to perturb the random number
+ sequence.
+
+ddd. Fixed several bugs that caused `declare -g' to not set the right global
+ variables or to misbehave when declaring global indexed arrays.
+
+eee. Fixed a logic bug that caused extended globbing in a multibyte locale to
+ cause failures when using the pattern substititution word expansions.
+
+fff. Fixed a bug that caused the `lastpipe' option to corrupt the file
+ descriptor used to read the script.
+
+ggg. Fixed a bug that causes the shell to delete DEL characters in the
+ expanded value of variables used in the same quoted string as variables
+ that expand to nothing.
+
+hhh. Fixed a bug that caused the shell to assign the wrong value from an
+ assignment like (( x=7 )) when `x' was an existing array variable.
+
+iii. Fixed a bug that caused the shell to misbehave when generating sequences
+ and the boundary values overflow an intmax_t.
+
+jjj. Fixed a bug caused expansion errors if an expansion of "$@" appeared
+ next to another expansion (e.g.. "${@}${x}").
+
+kkk. Fixed a potential buffer overflow bug when performing /dev/fd expansion.
+
+lll. Fixed a bug that resulted in an extra semicolon being added to compound
+ assignments when they were added to the history list.
+
+mmm. Fixed a bug that caused mapfile to read one extra line from the input.
+
+nnn. Fixed a bug that caused the mail checking code to use uninitialized
+ values.
+
+ooo. Fixed a bug that prevented history timestamps from being saved if the
+ history comment character is unset.
+
+ppp. Fixed a bug that caused the case-modifying expansions to not work with
+ multibyte characters.
+
+qqq. Fixed a bug that caused the edit-and-execute bindable readline command
+ to see the wrong data if invoked in the middle of a multi-line quoted
+ string.
+
+rrr. Fixed a bug that resulted in the shell returning the wrong exit status
+ for a background command on systems that recycle PIDs very quickly.
+
+sss. Fixed a bug that caused asynchronous group commands to not run any EXIT
+ trap defined in the body of the command.
+
+ttt. Fixed a bug that caused `eval "... ; return"' to not clean up properly.
+
+uuu. Fixed a bug that caused the shell to dump core if `read' reads an escaped
+ IFS whitespace character.
+
+vvv. Fixed a bug that caused BASH_COMMAND to be set to an incorrect value when
+ executing a (...) subshell.
+
+www. Fixed a couple of pointer aliasing bugs with the token string in arithmetic
+ evaluation.
+
+xxx. Fixed a bug with parsing multi-line command substitutions when reading
+ the `do' keyword followed by whitespace.
+
+yyy. Fixed a bug that caused the shell to seg fault if the time given to the
+ printf %(...)T format overflowed the value accepted by localtime(3).
+
+zzz. Fixed a problem with displaying help topics in two columns when the
+ translated text contained multibyte characters.
+
+aaaa. Fixed a bug with the extended globbing pattern matcher where a `*' was
+ followed by a negated extended glob pattern.
+
+bbbb. Fixed a race condition with short-lived coproc creation and reaping that
+ caused the child process to be reaped before the various coproc shell
+ variables were initialized.
+
+cccc. Fixed a bug where turning off `errexit' in command substitution subshells
+ was not reflected in $SHELLOPTS.
+
+dddd. Partially fixed an inconsistency in how the shell treated shell
+ functions run from an EXIT trap.
+
+eeee. Fixed a bug in how the shell invalidated FIFOs used for process
+ substitution when executing a pipeline (once rather than in every child).
+
+ffff. Fixed a bug that occurred when expanding a special variable ($@, $*)
+ within double quotes and the expansion resulted in an empty string.
+
+gggg. Fixed bugs with executing a SIGCHLD trap handler to make sure that it's
+ executed once per exited child.
+
+hhhh. Fixed a bug that caused `declare' and `test' to find variables that
+ had been given attributes but not assigned values. Such variables are
+ not set.
+
+iiii. Fixed a bug that caused commands in process substitutions to not look in
+ the local temporary environment when performing word expansions.
+
+jjjj. Fixed several problems with globstar expansions (**/**) returning null
+ filenames and multiple instances of the same pathname.
+
+kkkk. Fixed an oversight that did not allow the exit status of `coproc' to
+ be inverted using `!'.
+
+llll. Fixed a bug that caused the -e option to be re-enabled using `set -e'
+ even when executing in a context where -e is ignored.
+
+mmmm. Fixed a (mostly theoretical) bug with input lines longer than SIZE_MAX.
+
+nnnn. Fixed a bug that could result in double evaluation of command
+ substitutions when they appear in failed redirections.
+
+oooo. Fixed a bug that could cause seg faults during `mapfile' callbacks if
+ the callback unsets the array variable mapfile is using.
+
+pppp. Fixed several problems with variable assignments using ${var:=value}
+ when the variable assignment is supposed to have side effects.
+
+qqqq. Fixed a bug that caused a failure of an assignment statement preceding a
+ builtin caused the next invocation of a special builtin to exit the shell.
+
+rrrr. Fixed several problems with IFS when it appears in the temporary environment
+ and is used in redirections.
+
+ssss. Fixed a problem that caused IFS changes using ${IFS:=value} to modify
+ how preceding expansions were split.
+
+tttt. Fixed a problem that caused subshells to not run an EXIT trap they set.
+
+uuuu. Fixed a problem that caused shells started in posix mode to attempt to
+ import shell functions with invalid names from the environment. We now
+ print a warning.
+
+vvvv. Worked around a kernel problem that caused SIGCHLD to interrupt open(2)
+ on a FIFO used for process substitution, even if the SIGCHLD handler was
+ installed with the SA_RESTART flag.
+
+wwww. Fixed a problem that resulted in inconsistent expansion of $* and ${a[*]}.
+
+xxxx. Fixed a problem that caused `read -t' to crash when interrupted by
+ SIGINT.
+
+yyyy. Fixed a problem that caused pattern removal to fail randomly because the
+ pattern matcher read beyond the end of a string.
+
+zzzz. Fixed a bug that caused core dumps when shell functions tried to create
+ local shadow copies of special variables like GROUPS.
+
+aaaaa. Fixed a bug that caused SIGTERM to be occasionally lost by children of
+ interactive shells when it arrived before the child process reset the
+ handler from SIG_DFL.
+
+bbbbb. Fixed a bug that caused redirections like <&n- to leave file descriptor
+ n closed if executed with a builtin command.
+
+ccccc. Fixed a bug that caused incorrect completion quoting when completing a
+ word containing a globbing character with `show-all-if-ambiguous' set.
+
+ddddd. Fixed a bug that caused printf's %q format specifier not to quote a
+ tilde even if it appeared in a location where it would be subject to
+ tilde expansion.
+
+2. Changes to Readline
+
+a. Fixed a bug that did not allow the `dd', `cc', or `yy' vi editing mode
+ commands to work on the entire line.
+
+b. Fixed a bug that caused redisplay problems with prompts longer than 128
+ characters and history searches.
+
+c. Fixed a bug that caused readline to try and run code to modify its idea
+ of the screen size in a signal handler context upon receiving a SIGWINCH.
+
+d. Fixed a bug that caused the `meta' key to be enabled beyond the duration
+ of an individual call top readline().
+
+e. Added a workaround for a wcwidth bug in Mac OS X that caused readline's
+ redisplay to mishandle zero-width combining characters.
+
+f. Fixed a bug that caused readline to `forget' part of a key sequence when
+ a multiple-key sequence caused it to break out of an incremental search.
+
+g. Fixed bugs that caused readline to execute code in a signal handler
+ context if interrupted while reading from the file system during completion.
+
+h. Fixed a bug that caused readline to `forget' part of a key sequence when
+ reading an unbound multi-character key sequence.
+
+i. Fixed a bug that caused Readline's signal handlers to be installed beyond
+ the bounds of a single call to readline().
+
+j. Fixed a bug that caused the `.' command to not redo the most recent `R'
+ command in vi mode.
+
+k. Fixed a bug that caused ignoring case in completion matches to result in
+ readline using the wrong match.
+
+l. Paren matching now works in vi insert mode.
+
+m. Fix menu-completion to make show-all-if-ambiguous and menu-complete-display-prefix
+ work together.
+
+n. Fixed a bug that didn't allow the `cc', `dd', or `yy' commands to be redone
+ in vi editing mode.
+
+o. Fixed a bug that caused the filename comparison code to not compare
+ multibyte characters correctly when using case-sensitive or case-mapping
+ comparisons.
+
+p. Fixed the input reading loop to call the input hook function only when there
+ is no terminal input available.
+
+q. Fixed a bug that caused binding a macro to a multi-character key sequence
+ where the sequence and macro value share a common prefix to not perform
+ the macro replacement.
+
+r. Fixed several redisplay errors with multibyte characters and prompts
+ containing invisible characters when using horizontal scrolling.
+
+s. Fixed a bug that caused redisplay errors when trying to overwrite
+ existing characters using multibyte characters.
+
+3. New Features in Bash
+
+a. The `helptopic' completion action now maps to all the help topics, not just
+ the shell builtins.
+
+b. The `help' builtin no longer does prefix substring matching, so `help read'
+ does not match `readonly'.
+
+c. The shell can be compiled to not display a message about processes that
+ terminate due to SIGTERM.
+
+d. Non-interactive shells now react to the setting of checkwinsize and set
+ LINES and COLUMNS after a foreground job exits.
+
+e. There is a new shell option, `globasciiranges', which, when set to on,
+ forces globbing range comparisons to use character ordering as if they
+ were run in the C locale.
+
+f. There is a new shell option, `direxpand', which makes filename completion
+ expand variables in directory names in the way bash-4.1 did.
+
+g. In Posix mode, the `command' builtin does not change whether or not a
+ builtin it shadows is treated as an assignment builtin.
+
+h. The `return' and `exit' builtins accept negative exit status arguments.
+
+i. The word completion code checks whether or not a filename containing a
+ shell variable expands to a directory name and appends `/' to the word
+ as appropriate. The same code expands shell variables in command names
+ when performing command completion.
+
+j. In Posix mode, it is now an error to attempt to define a shell function
+ with the same name as a Posix special builtin.
+
+k. When compiled for strict Posix conformance, history expansion is disabled
+ by default.
+
+l. The history expansion character (!) does not cause history expansion when
+ followed by the closing quote in a double-quoted string.
+
+m. `complete' and its siblings compgen/compopt now takes a new `-o noquote'
+ option to inhibit quoting of the completions.
+
+n. Setting HISTSIZE to a value less than zero causes the history list to be
+ unlimited (setting it 0 zero disables the history list).
+
+o. Setting HISTFILESIZE to a value less than zero causes the history file size
+ to be unlimited (setting it to 0 causes the history file to be truncated
+ to zero size).
+
+p. The `read' builtin now skips NUL bytes in the input.
+
+q. There is a new `bind -X' option to print all key sequences bound to Unix
+ commands.
+
+r. When in Posix mode, `read' is interruptible by a trapped signal. After
+ running the trap handler, read returns 128+signal and throws away any
+ partially-read input.
+
+s. The command completion code skips whitespace and assignment statements
+ before looking for the command name word to be completed.
+
+t. The build process has a new mechanism for constructing separate help files
+ that better reflects the current set of compilation options.
+
+u. The -nt and -ot options to test now work with files with nanosecond
+ timestamp resolution.
+
+v. The shell saves the command history in any shell for which history is
+ enabled and HISTFILE is set, not just interactive shells.
+
+w. The shell has `nameref' variables and new -n(/+n) options to declare and
+ unset to use them, and a `test -R' option to test for them.
+
+x. The shell now allows assigning, referencing, and unsetting elements of
+ indexed arrays using negative subscripts (a[-1]=2, echo ${a[-1]}) which
+ count back from the last element of the array.
+
+y. The {x}<word redirection feature now allows words like {array[ind]} and
+ can use variables with special meanings to the shell (e.g., BASH_XTRACEFD).
+
+z. There is a new CHILD_MAX special shell variable; its value controls the
+ number of exited child statuses the shell remembers.
+
+aa. There is a new configuration option (--enable-direxpand-default) that
+ causes the `direxpand' shell option to be enabled by default.
+
+bb. Bash does not do anything special to ensure that the file descriptor
+ assigned to X in {x}<foo remains open after the block containing it
+ completes.
+
+cc. The `wait' builtin has a new `-n' option to wait for the next child to
+ change status.
+
+dd. The `printf' %(...)T format specifier now uses the current time if no
+ argument is supplied.
+
+ee. There is a new variable, BASH_COMPAT, that controls the current shell
+ compatibility level.
+
+ff. The `popd' builtin now treats additional arguments as errors.
+
+gg. The brace expansion code now treats a failed sequence expansion as a
+ simple string and will continue to expand brace terms in the remainder
+ of the word.
+
+4. New Features in Readline
+
+a. Readline is now more responsive to SIGHUP and other fatal signals when
+ reading input from the terminal or performing word completion but no
+ longer attempts to run any not-allowable functions from a signal handler
+ context.
+
+b. There are new bindable commands to search the history for the string of
+ characters between the beginning of the line and the point
+ (history-substring-search-forward, history-substring-search-backward)
+
+c. Readline allows quoted strings as the values of variables when setting
+ them with `set'. As a side effect, trailing spaces and tabs are ignored
+ when setting a string variable's value.
+
+d. The history library creates a backup of the history file when writing it
+ and restores the backup on a write error.
+
+e. New application-settable variable: rl_filename_stat_hook: a function called
+ with a filename before using it in a call to stat(2). Bash uses it to
+ expand shell variables so things like $HOME/Downloads have a slash
+ appended.
+
+f. New bindable function `print-last-kbd-macro', prints the most-recently-
+ defined keyboard macro in a reusable format.
+
+g. New user-settable variable `colored-stats', enables use of colored text
+ to denote file types when displaying possible completions (colored analog
+ of visible-stats).
+
+h. New user-settable variable `keyseq-timout', acts as an inter-character
+ timeout when reading input or incremental search strings.
+
+i. New application-callable function: rl_clear_history. Clears the history list
+ and frees all readline-associated private data.
+
+j. New user-settable variable, show-mode-in-prompt, adds a characters to the
+ beginning of the prompt indicating the current editing mode.
+
+k. New application-settable variable: rl_input_available_hook; function to be
+ called when readline needs to check whether there is data available on its
+ input source. The default hook checks rl_instream.
+
+l. Readline calls an application-set event hook (rl_signal_event_hook) after
+ it gets a signal while reading input (read returns -1/EINTR but readline
+ does not handle the signal immediately) to allow the application to handle
+ or otherwise note it. Not currently called for SIGHUP or SIGTERM.
+
+m. If the user-settable variable `history-size' is set to a value less than
+ 0, the history list size is unlimited.
+
+------------------------------------------------------------------------------
+This document details the changes between this version, bash-4.2-release,
+and the previous version, bash-4.2-rc2.
+
+1. Changes to Bash
+
+a. Fixed a bug that caused some variables to be clobbered by a longjmp,
+ resulting in stack corruption.
+
+------------------------------------------------------------------------------
+This document details the changes between this version, bash-4.2-rc2,
+and the previous version, bash-4.2-rc1.
+
+1. Changes to Bash
+
+a. Changes to bash_directory_completion_hook so that it's assigned to the
+ readline rl_directory_rewrite_hook variable, which modifies the directory
+ name passed to opendir without modifying the directory name the user
+ typed.
+
+b. Fixed bug in select builtin that caused it to not terminate correctly if
+ the read timed out due to $TMOUT.
+
+c. Fixed a problem that resulted in non-repeatable sequences of random
+ numbers when RANDOM=0.
+
+------------------------------------------------------------------------------
+This document details the changes between this version, bash-4.2-rc1,
+and the previous version, bash-4.2-beta.
+
+1. Changes to Bash
+
+a. Fixed a bug that caused some redirection errors to leak file descriptors.
+
+b. Fixed a bug that caused unary `+' and `-' arithmetic operators to have a
+ higher precedence than unary `!' and `~'.
+
+c. Fixed a bug that caused simple commands in a pipeline to affect the exit
+ status ($?) seen by subsequent pipeline commands.
+
+d. A number of cygwin-specific changes to avoid the use of text-mode files
+ and file access, and to make sure that \r is handled correctly.
+
+e. Fixed a bug that caused the read builtin to not return failure if an
+ attempt is made to assign to a readonly variable.
+
+f. Fixed a bug that caused some builtin usage messages to not be translated.
+
+g. Fixed a bug that caused the getopts builtin to not return failure if an
+ attempt is made to assign to a readonly variable. Now it returns 2.
+
+h. Fixed the cd and pwd builtins to return failure if PWD is readonly and
+ cannot be assigned to.
+
+i. Added code to check the return value of access(2) on Solaris systems,
+ since it returns success for executable tests (e.g., `test -x') when
+ run by root, even if the file permissions don't allow execution.
+
+2. Changes to Readline
+
+a. Fixed a bug that caused directory names in words to be completed to not
+ be dequoted correctly.
+
+3. New Features in Bash
+
+4. New Features in Readline
+
+------------------------------------------------------------------------------
+This document details the changes between this version, bash-4.2-beta,
+and the previous version, bash-4.2-alpha.
+
+1. Changes to Bash
+
+a. Fixed a bug that caused the \W prompt string escape to not add a closing
+ NULL.
+
+b. Fixed a bug that caused partially-quoted words that were not subject to
+ word splitting to retained quoted NULLs.
+
+c. Added considerable efficiency speedups when pattern matching in multibyte
+ locales by skipping multibyte character functions where possible.
+
+d. Added considerable speedups to variable expansion when in multibyte locales.
+
+e. Fixed a bug that caused the expansion of $* when there are no positional
+ parameters to cause the shell to dump core when used in a pattern
+ matching context.
+
+f. Fixed a bug that caused variable expansions preceding regular builtins to
+ not change the shell environment during their execution.
+
+2. Changes to Readline
+
+a. Fixed a bug that made an explicit argument of 0 to yank-last-arg behave
+ as if it were a negative argument.
+
+------------------------------------------------------------------------------
+This document details the changes between this version, bash-4.2-alpha,
+and the previous version, bash-4.1-release.
+
+1. Changes to Bash
+
+a. Fixed a bug in the parser when processing alias expansions containing
+ quoted newlines.
+
+b. Fixed a memory leak in associative array expansion.
+
+c. Fixed a bug that caused quoted here-strings to be requoted when printed.
+
+d. Fixed a bug in arithmetic expansion that caused the index in an array
+ expansion to be evaluated twice under certain circumstances.
+
+e. Fixed several bugs with the expansion and display of variables that have
+ been given attributes but not values and are technically unset.
+
+f. Fixed a bug that caused core dumps when using filename completion that
+ expands to a filename containing a globbing character.
+
+g. Fixed a bug that caused assignment statements preceding a special builtin
+ when running in Posix mode to not persist after the builtin completed
+ when the special builtin was executed in a shell function without any
+ local variables.
+
+h. Fixed a bug that caused a command to remain in the hash table even after
+ `hash command' did not find anything if there was already an existing
+ hashed pathname.
+
+i. Fixed several bugs caused by executing unsafe functions from a signal
+ handler in the cases where a signal handler is executed immediately
+ rather than setting a flag for later execution.
+
+j. Fixed a bug that caused some internal flag variables to be set
+ incorrectly if `read -t' timed out.
+
+k. Fixed a Posix compatibility issue by making sure that a backslash escaping
+ a `}' within a double-quoted ${...} parameter expansion is removed as part
+ of the parameter expansion.
+
+l. Fixed a bug that caused execution of a trap to overwrite PIPESTATUS.
+
+m. Fixed a bug that caused here documents to not be displayed correctly
+ when attached to commands inside compound commands.
+
+n. Fixed a bug that caused the printf builtin to use the wrong precision
+ when using the `*' modifier.
+
+o. Fixed a bug that caused an arriving SIGCHLD to interrupt output functions
+ like those invoked by echo or printf.
+
+p. Changed to use a more robust mechanism than eaccess(2) when test is
+ checking filenames for execution permission.
+
+q. Fixed a bug that caused spurious semicolons to be added into the command
+ history in certain cases.
+
+r. Fixed a bug that caused the shell to free non-allocated memory when
+ unsetting element 0 of an associative array after it was assigned
+ implicitly.
+
+s. Fixed a bug that could cause the shell to dump core if using the `v'
+ vi editing command on a multi-line command.
+
+t. Fixed a bug that left FIFOs opened by process substitutions open long
+ enough to potentially cause file descriptor exhaustion when running a
+ shell function or shell builtin.
+
+u. Fixed a bug that caused the history expansion functions to not recognize
+ process substitution or extended glob patterns as single words.
+
+v. Fixed a bug that caused restricted shells to set a restricted command's
+ exit status incorrectly.
+
+w. Fixed a bug that caused bash to ignore the wrong set of filenames when
+ completing a command using the `complete-filename' readline command.
+
+x. Fixed a bug that caused a -PID argument following a -s sig or -n sig to
+ not be interpreted as a signal specification.
+
+y. Changed posix-mode behavior of a parse error in a `.' script or `eval'
+ command to exit the shell under Posix-specified conditions. Previous
+ versions printed a warning.
+
+z. Fixed a bug in \W prompt expansion that resulted in incorrect expansion
+ in the event of overlapping strings.
+
+aa. Fixed a bug that caused the := parameter expansion operator to return the
+ wrong value as the result of the expansion.
+
+bb. When in Posix mode, a single quote is not treated specially in a
+ double-quoted ${...} expansion, unless the expansion operator is
+ # or % or the non-Posix `//', `^', and `,'. In particular, it does
+ not define a new quoting context. This is from Posix interpretation 221.
+
+cc. Fixed a bug that inadvertently allowed program names containing slashes
+ to be entered into the command hash table.
+
+dd. Fixed a bug that caused the select builtin to incorrectly compute the
+ display width of the arguments in the presence of multibyte characters.
+
+ee. Fixed a bug that caused bash to not change the xtrace file descriptor if
+ BASH_XTRACEFD was found in the shell environment at startup.
+
+ff. Fixed a memory leak in the pattern removal parameter expansion.
+
+gg. Fixed a bug that caused SIGINT to fail to interrupt a nested loop if the
+ loop was in a pipeline.
+
+hh. Fixed a problem in $(...) parsing that caused the parser to add an extra
+ space to a here-document delimiter if the first word contained a `/'.
+
+ii. Fixed a bug that caused functions defined with the `function' reserved
+ word to require braces around the function body.
+
+jj. Fixed a bug that caused bash to dump core when a variable expansion being
+ used as an array subscript failed.
+
+kk. Fixed a bug that caused bash to dump core if the case-modification
+ expansions were used on a variable with a null value.
+
+ll. Fixed a bug that caused partially-quoted strings to be split incorrectly
+ if a variable with a null value was expanded within double quotes.
+
+mm. The pattern substitution word expansion has been sped up dramatically
+ when running in a locale with multibyte characters.
+
+nn. Fixed a bug that caused history -a to not write the correct lines to
+ the history file if all the new lines in the history list were added
+ since the last time the history file was read or written.
+
+oo. Fixed a bug that caused completion of a word with an unclosed `` command
+ substitution to set the prompt incorrectly.
+
+pp. Fixed a bug that caused extended globbing patterns in $HISTIGNORE or
+ $GLOBIGNORE to be incorrectly scanned.
+
+qq. Fixed a bug caused by closing file descriptors 3-20 on shell startup. The
+ shell now sets them to close-on-exec.
+
+rr. Fixed a bug that caused the exit status of `exec file' to be set incorrectly
+ if `file' was a directory.
+
+ss. Fixed a bug in the `.' builtin to make a non-interactive posix-mode shell
+ exit if the file argument to `.' is not found. Prefixing exec with
+ `command' makes the shell not exit. Posix requires this behavior.
+
+tt. Fixed a bug that caused `sh -c 'command exec; exit 1' to hang.
+
+uu. Fixed a bug in $(...) command substitution parsing that caused the shell
+ to treat backslash-newline incorrectly when parsing a comment.
+
+vv. Fixed bug that caused brace expansion sequence generation to misbehave
+ when supplied integers greater than 2**31 - 1.
+
+ww. Fixed a bug that caused failure to save file descriptors for redirections
+ to corrupt shell file descriptors.
+
+xx. Fixed a bug that caused bash-forward-shellword to not correctly handle
+ quoted strings.
+
+2. Changes to Readline
+
+a. Fixed a bug that caused the unconverted filename to be added to the list of
+ completions when the application specified filename conversion functions.
+
+b. Fixed a bug that caused the wrong filename to be passed to opendir when the
+ application has specified a filename dequoting function.
+
+c. Fixed a bug when repeating a character search in vi mode in the case where
+ there was no search to repeat.
+
+d. When show-all-if-ambiguous is set, the completion routines no longer insert
+ a common match prefix that is shorter than the text being completed.
+
+e. The full set of vi editing commands may now be used in callback mode.
+
+f. Fixed a bug that caused readline to not update its idea of the terminal
+ dimensions while running in `no-echo' mode.
+
+h. Fixed a bug that caused readline to dump core if an application called
+ rl_prep_terminal without setting rl_instream.
+
+i. Fixed a bug that caused meta-prefixed characters bound to incremental
+ search forward or backward to not be recognized if they were typed
+ subsequently.
+
+j. The incremental search code treats key sequences that map to the same
+ functions as (default) ^G, ^W, and ^Y as equivalent to those characters.
+
+k. Fixed a bug in menu-complete that caused it to misbehave with large
+ negative argument.
+
+l. Fixed a bug that caused vi-mode yank-last-arg to ring the bell when invoked
+ at the end of the line.
+
+3. New Features in Bash
+
+a. `exec -a foo' now sets $0 to `foo' in an executable shell script without a
+ leading #!.
+
+b. Subshells begun to execute command substitutions or run shell functions or
+ builtins in subshells do not reset trap strings until a new trap is
+ specified. This allows $(trap) to display the caller's traps and the
+ trap strings to persist until a new trap is set.
+
+c. `trap -p' will now show signals ignored at shell startup, though their
+ disposition still cannot be modified.
+
+d. $'...', echo, and printf understand \uXXXX and \UXXXXXXXX escape sequences.
+
+e. declare/typeset has a new `-g' option, which creates variables in the
+ global scope even when run in a shell function.
+
+f. test/[/[[ have a new -v variable unary operator, which returns success if
+ `variable' has been set.
+
+g. Posix parsing changes to allow `! time command' and multiple consecutive
+ instances of `!' (which toggle) and `time' (which have no cumulative
+ effect).
+
+h. Posix change to allow `time' as a command by itself to print the elapsed
+ user, system, and real times for the shell and its children.
+
+j. $((...)) is always parsed as an arithmetic expansion first, instead of as
+ a potential nested command substitution, as Posix requires.
+
+k. A new FUNCNEST variable to allow the user to control the maximum shell
+ function nesting (recursive execution) level.
+
+l. The mapfile builtin now supplies a third argument to the callback command:
+ the line about to be assigned to the supplied array index.
+
+m. The printf builtin has a new %(fmt)T specifier, which allows time values
+ to use strftime-like formatting.
+
+n. There is a new `compat41' shell option.
+
+o. The cd builtin has a new Posix-mandated `-e' option.
+
+p. Negative subscripts to indexed arrays, previously errors, now are treated
+ as offsets from the maximum assigned index + 1.
+
+q. Negative length specifications in the ${var:offset:length} expansion,
+ previously errors, are now treated as offsets from the end of the variable.
+
+r. Parsing change to allow `time -p --'.
+
+s. Posix-mode parsing change to not recognize `time' as a keyword if the
+ following token begins with a `-'. This means no more Posix-mode
+ `time -p'. Posix interpretation 267.
+
+t. There is a new `lastpipe' shell option that runs the last command of a
+ pipeline in the current shell context. The lastpipe option has no
+ effect if job control is enabled.
+
+u. History expansion no longer expands the `$!' variable expansion.
+
+v. Posix mode shells no longer exit if a variable assignment error occurs
+ with an assignment preceding a command that is not a special builtin.
+
+w. Non-interactive mode shells exit if -u is enabled and an attempt is made
+ to use an unset variable with the % or # expansions, the `//', `^', or
+ `,' expansions, or the parameter length expansion.
+
+x. Posix-mode shells use the argument passed to `.' as-is if a $PATH search
+ fails, effectively searching the current directory. Posix-2008 change.
+
+4. New Features in Readline
+
+a. The history library does not try to write the history filename in the
+ current directory if $HOME is unset. This closes a potential security
+ problem if the application does not specify a history filename.
+
+b. New bindable variable `completion-display-width' to set the number of
+ columns used when displaying completions.
+
+c. New bindable variable `completion-case-map' to cause case-insensitive
+ completion to treat `-' and `_' as identical.
+
+d. There are new bindable vi-mode command names to avoid readline's case-
+ insensitive matching not allowing them to be bound separately.
+
+e. New bindable variable `menu-complete-display-prefix' causes the menu
+ completion code to display the common prefix of the possible completions
+ before cycling through the list, instead of after.
+
+------------------------------------------------------------------------------
+This document details the changes between this version, bash-4.1-rc,
+and the previous version, bash-4.1-beta.
+
+1. Changes to Bash
+
+a. Fixed a bug that caused printf to not return a partial value when it
+ encountered an error while converting an integer argument.
+
+b. Fixed a bug that caused setting one of the compatNN options to not
+ turn off the others.
+
+c. The (undocumented) --wordexp option is no longer included by default.
+
+d. Fixed a bug in conditional command execution that caused it to not
+ correctly ignore the exit status under certain circumstances.
+
+e. Added a configure-time check for correctly-working asprintf/snprintf.
+
+f. Fixed some problems with line number calculation and display when sourcing
+ a file in an interactive shell.
+
+g. Fixed a bug that caused the shell to crash when using `declare -A foo=bar'.
+
+h. Fixed a bug that caused an off-by-one error when calculating the directories
+ to display with the PROMPT_DIRTRIM option.
+
+2. Changes to Readline
+
+a. Fixed a bug that caused applications using the callback interface to not
+ react to SIGINT (or other signals) until another character arrived.
+
+------------------------------------------------------------------------------
+This document details the changes between this version, bash-4.1-beta,
+and the previous version, bash-4.1-alpha.
+
+1. Changes to Bash
+
+a. Fixed a bug in mapfile that caused the shell to crash if it was passed the
+ name of an associative array.
+
+b. Fixed a bug that caused the shell to incorrectly split case patterns if
+ they contained characters in $IFS.
+
+c. Fixed a bug that caused the shell to set $? to the wrong value when using
+ a construct ending with a variable assignment with set -x enabled and PS4
+ containing a command substitution.
+
+d. Fixed a bug that caused the shell to read commands incorrectly if an
+ expansion error occurred under certain conditions in a user-specified
+ subshell.
+
+e. Fixed a bug that caused the shell to set $? incorrectly if a parse error
+ occurred in an evaluation context ("eval", trap command, dot script, etc.)
+
+f. Fixed a bug that caused the shell to attempt command substitution
+ completion within a single-quoted string.
+
+g. Fixed a bug that caused the shell to insert an extra single quote during
+ word completion.
+
+h. Fixed a bug that caused the shell to crash if invoked with the environment
+ variable EMACS having a null value.
+
+i. Fixed a bug that caused bash to incorrectly report the presence of new
+ mail in a `maildir' environment.
+
+j. Fixed a bug that caused the shell to not recognize a here-document ending
+ delimiter inside a command substitution.
+
+k. Fixed a bug that caused the shell to crash when a a dynamic array variable
+ was assigned a scalar value.
+
+2. Changes to Readline
+
+3. New Features in Bash
+
+a. The mapfile/readarray builtin no longer stores the commands it invokes via
+ callbacks in the history list.
+
+b. There is a new `compat40' shopt option.
+
+c. The < and > operators to [[ do string comparisons using the current locale
+ only if the compatibility level is greater than 40 (set to 41 by default).
+
+4. New Features in Readline
+
+------------------------------------------------------------------------------
+This document details the changes between this version, bash-4.1-alpha,
+and the previous version, bash-4.0-release.
+
+1. Changes to Bash
+
+a. Fixed bugs in the parser involving new parsing of the commands contained
+ in command substitution when the substitution is read.
+
+b. Fixed a bug that caused the shell to dump core when performing programmable
+ completion using a shell function.
+
+c. Fixed a bug in `mapfile' that caused it to invoke callbacks at the wrong
+ time.
+
+d. Fixed a bug that caused the shell to dump core when listing jobs in the
+ `exit' builtin.
+
+e. Fixed several bugs encountered when reading subscripts in associative
+ array assignments and expansions.
+
+f. Fixed a bug that under some circumstances caused an associative array to
+ be converted to an indexed array.
+
+g. Fixed a bug that caused syntax errors and SIGINT interrupts to not set
+ $? to a value > 128.
+
+h. Fixed a bug that caused the shell to remove FIFOs associated with process
+ substitution inside shell functions.
+
+i. Fixed a bug that caused terminal attributes to not be reset when the
+ `read' builtin timed out.
+
+j. Fixed a bug in brace expansion that caused unwanted zero padding of the
+ expanded terms.
+
+k. Fixed a bug that prevented the |& construct from working as intended when
+ used with a simple command with additional redirections.
+
+l. Fixed a bug with the case statment ;& terminator that caused the shell to
+ dereference a NULL pointer.
+
+m. Fixed a bug that caused assignment statements or redirections preceding
+ a simple command name to inhibit alias expansion.
+
+n. Fixed the behavior of `set -u' to conform to the latest Posix interpretation:
+ every expansion of an unset variable except $@ and $* will cause the
+ shell to exit.
+
+o. Fixed a bug that caused double-quoted expansions of $* inside word
+ expansions like ${x#$*} to not expand properly when $IFS is empty.
+
+p. Fixed a bug that caused traps to set $LINENO to the wrong value when they
+ execute.
+
+q. Fixed a bug that caused off-by-one errors when computing history lines in
+ the `fc' builtin.
+
+r. Fixed a bug that caused some terminating signals to not exit the shell
+ quickly enough, forcing the kernel to send the signal (e.g., SIGSEGV)
+ multiple times.
+
+s. Fixed a bug that caused the shell to attempt to add empty lines to the
+ history list when reading here documents.
+
+t. Made some internal changes that dramatically speeds up sequential indexed
+ array access.
+
+u. Fixed a bug that caused the shell to write past the end of a string when
+ completing a double-quoted string ending in a backslash.
+
+v. Fixed a bug that caused the shell to replace too many characters when a
+ pattern match was null in a ${foo//bar} expansion.
+
+w. Fixed bugs in the expansion of ** that caused duplicate directory names
+ and the contents of the current directory to be omitted.
+
+x. Fixed a bug that caused $? to not be set correctly when referencing an
+ unset variable with set -u and set -e enabled.
+
+y. Fixed a bug caused by executing an external program from the DEBUG trap
+ while a pipeline was running. The effect was to disturb the pipeline
+ state, occasionally causing it to hang.
+
+z. Fixed a bug that caused the ** glob expansion to dump core if it
+ encountered an unsearchable directory.
+
+aa. Fixed a bug that caused `command -v' and `command -V' to not honor the
+ path set by the -p option.
+
+bb. Fixed a bug that caused brace expansion to take place too soon in some
+ compound array assignments.
+
+cc. Fixed a bug that caused programmable completion functions' changes to
+ READLINE_POINT to not be reflected back to readline.
+
+dd. Fixed a bug that caused the shell to dump core if a trap was executed
+ during a shell assignment statement.
+
+ee. Fixed an off-by-one error when computing the number of positional
+ parameters for the ${@:0:n} expansion.
+
+ff. Fixed a problem with setting COMP_CWORD for programmable completion
+ functions that could leave it set to -1.
+
+gg. Fixed a bug that caused the ERR trap to be triggered in some cases where
+ `set -e' would not have caused the shell to exit.
+
+hh. Fixed a bug that caused changes made by `compopt' to not persist past the
+ completion function in which compopt was executed.
+
+ii. Fixed a bug that caused the list of hostname completions to not be cleared
+ when HOSTNAME was unset.
+
+jj. Fixed a bug that caused variable expansion in here documents to look in
+ any temporary environment.
+
+kk. Bash and readline can now convert file names between precomposed and
+ decomposed Unicode on Mac OS X ("keyboard" and file system forms,
+ respectively). This affects filename completion (using new
+ rl_filename_rewrite_hook), globbing, and readline redisplay.
+
+ll. The ERR and EXIT traps now see a non-zero value for $? when a parser
+ error after set -e has been enabled causes the shell to exit.
+
+mm. Fixed a bug that in brace expansion that caused zero-prefixed terms to
+ not contain the correct number of digits.
+
+nn. Fixed a bug that caused the shell to free non-allocated memory when
+ unsetting an associative array which had had a value implicitly assigned
+ to index "0".
+
+oo. Fixed a memory leak in the ${!prefix@} expansion.
+
+pp. Fixed a bug that caused printf to not correctly report all write errors.
+
+qq. Fixed a bug that caused single and double quotes to act as delimiters
+ when splitting a command line into words for programmable completion.
+
+rr. Fixed a bug that caused ** globbing that caused **/path/* to match every
+ directory, not just those matching `path'.
+
+ss. Fixed a bug that caused the shell to dump core when running `help' without
+ arguments if the terminal width was fewer than 7 characters.
+
+2. Changes to Readline
+
+a. The SIGWINCH signal handler now avoids calling the redisplay code if
+ one arrives while in the middle of redisplay.
+
+b. Changes to the timeout code to make sure that timeout values greater
+ than one second are handled better.
+
+c. Fixed a bug in the redisplay code that was triggered by a prompt
+ containing invisible characters exactly the width of the screen.
+
+d. Fixed a bug in the redisplay code encountered when running in horizontal
+ scroll mode.
+
+e. Fixed a bug that prevented menu completion from properly completing
+ filenames.
+
+f. Fixed a redisplay bug caused by a multibyte character causing a line to
+ wrap.
+
+g. Fixed a bug that caused key sequences of two characters to not be
+ recognized when a longer sequence identical in the first two characters
+ was bound.
+
+h. Fixed a bug that caused history expansion to be attempted on $'...'
+ single-quoted strings.
+
+i. Fixed a bug that caused incorrect redisplay when the prompt contained
+ multibyte characters in an `invisible' sequence bracketed by \[ and
+ \].
+
+j. Fixed a bug that caused history expansion to short-circuit after
+ encountering a multibyte character.
+
+3. New Features in Bash
+
+a. Here-documents within $(...) command substitutions may once more be
+ delimited by the closing right paren, instead of requiring a newline.
+
+b. Bash's file status checks (executable, readable, etc.) now take file
+ system ACLs into account on file systems that support them.
+
+c. Bash now passes environment variables with names that are not valid
+ shell variable names through into the environment passed to child
+ processes.
+
+d. The `execute-unix-command' readline function now attempts to clear and
+ reuse the current line rather than move to a new one after the command
+ executes.
+
+e. `printf -v' can now assign values to array indices.
+
+f. New `complete -E' and `compopt -E' options that work on the "empty"
+ completion: completion attempted on an empty command line.
+
+g. New complete/compgen/compopt -D option to define a `default' completion:
+ a completion to be invoked on command for which no completion has been
+ defined. If this function returns 124, programmable completion is
+ attempted again, allowing a user to dynamically build a set of completions
+ as completion is attempted by having the default completion function
+ install individual completion functions each time it is invoked.
+
+h. When displaying associative arrays, subscripts are now quoted.
+
+i. Changes to dabbrev-expand to make it more `emacs-like': no space appended
+ after matches, completions are not sorted, and most recent history entries
+ are presented first.
+
+j. The [[ and (( commands are now subject to the setting of `set -e' and the
+ ERR trap.
+
+k. The source/. builtin now removes NUL bytes from the file before attempting
+ to parse commands.
+
+l. There is a new configuration option (in config-top.h) that forces bash to
+ forward all history entries to syslog.
+
+m. A new variable $BASHOPTS to export shell options settable using `shopt' to
+ child processes.
+
+n. There is a new confgure option that forces the extglob option to be
+ enabled by default.
+
+o. New variable $BASH_XTRACEFD; when set to an integer bash will write xtrace
+ output to that file descriptor.
+
+p. If the optional left-hand-side of a redirection is of the form {var}, the
+ shell assigns the file descriptor used to $var or uses $var as the file
+ descriptor to move or close, depending on the redirection operator.
+
+q. The < and > operators to the [[ conditional command now do string
+ comparison according to the current locale.
+
+r. Programmable completion now uses the completion for `b' instead of `a'
+ when completion is attempted on a line like: a $(b c.
+
+s. Force extglob on temporarily when parsing the pattern argument to
+ the == and != operators to the [[ command, for compatibility.
+
+t. Changed the behavior of interrupting the wait builtin when a SIGCHLD is
+ received and a trap on SIGCHLD is set to be Posix-mode only.
+
+u. The read builtin has a new `-N nchars' option, which reads exactly NCHARS
+ characters, ignoring delimiters like newline.
+
+4. New Features in Readline
+
+a. New bindable function: menu-complete-backward.
+
+b. In the vi insertion keymap, C-n is now bound to menu-complete by default,
+ and C-p to menu-complete-backward.
+
+c. When in vi command mode, repeatedly hitting ESC now does nothing, even
+ when ESC introduces a bound key sequence. This is closer to how
+ historical vi behaves.
+
+d. New bindable function: skip-csi-sequence. Can be used as a default to
+ consume key sequences generated by keys like Home and End without having
+ to bind all keys.
+
+e. New application-settable function: rl_filename_rewrite_hook. Can be used
+ to rewite or modify filenames read from the file system before they are
+ compared to the word to be completed.
+
+f. New bindable variable: skip-completed-text, active when completing in the
+ middle of a word. If enabled, it means that characters in the completion
+ that match characters in the remainder of the word are "skipped" rather
+ than inserted into the line.
+
+g. The pre-readline-6.0 version of menu completion is available as
+ "old-menu-complete" for users who do not like the readline-6.0 version.
+
+h. New bindable variable: echo-control-characters. If enabled, and the
+ tty ECHOCTL bit is set, controls the echoing of characters corresponding
+ to keyboard-generated signals.
+
+i. New bindable variable: enable-meta-key. Controls whether or not readline
+ sends the smm/rmm sequences if the terminal indicates it has a meta key
+ that enables eight-bit characters.
+
+------------------------------------------------------------------------------
+This document details the changes between this version, bash-4.0-release,
+and the previous version, bash-4.0-rc1.
+
+1. Changes to Bash
+
+a. Changed the message printed when setlocale(3) fails to only include the
+ strerror error text if the call changes errno.
+
+b. Changed trap command execution to reset the line number before running a
+ trap (except DEBUG and RETURN traps).
+
+c. Fixed behavior of case-modifiying word expansions to not work on
+ individual words within a variable's value.
+
+d. Fixed a bug that caused mapfile to not be interruptible when run in an
+ interactive shell.
+
+e. Fixed a bug that caused mapfile to not run callbacks for the first line
+ read.
+
+f. Fixed a bug that caused mapfile to not honor EOF typed in an interactive
+ shell.
+
+g. Fixed the coprocess reaping code to not run straight from a signal handler.
+
+h. Fixed a bug that caused printf -b to ignore the first % conversion specifier
+ in the format string on 64-bit systems.
+
+i. Fixed a bug that caused incorrect word splitting when `:', `=', or `~'
+ appeared in $IFS.
+
+j. Fixed a bug that caused data corruption in the programmable completion code
+ when a shell function called from a completion aborted execution.
+
+k. Fixed a bug that caused the CPU usage reported by the `time' builtin to be
+ capped at 100%.
+
+l. Changed behavior of shell when -e option is in effect to reflect consensus
+ of Posix shell standardization working group.
+
+m. Fixed a bug introduced in bash-4.0-alpha that caused redirections to not
+ be displayed by `type' or `declare' when appearing in functions under
+ certain circumstances.
+
+2. Changes to Readline
+
+a. Fixed a bug that caused !(...) extended glob patterns to inhibit later
+ history expansion.
+
+b. Reworked the signal handling to avoid calling disallowed functions from a
+ signal handler.
+
+3. New Features in Bash
+
+a. `readarray' is now a synonym for `mapfile'.
+------------------------------------------------------------------------------
+This document details the changes between this version, bash-4.0-rc1,
+and the previous version, bash-4.0-beta2.
+
+1. Changes to Bash
+
+a. Fixed a bug that caused parsing errors when a $()-style command
+ substitution was follwed immediately by a quoted newline.
+
+b. Fixed a bug that caused extended shell globbing patterns beginning with
+ `*(' to not work when used with pattern substitution word expansions.
+
+------------------------------------------------------------------------------
+This document details the changes between this version, bash-4.0-beta2,
+and the previous version, bash-4.0-beta.
+
+1. Changes to Bash
+
+a. Fixed a bug that caused failed word expansions to set $? but not
+ PIPESTATUS.
+
+b. Changed filename completion to quote the tilde in a filename with a
+ leading tilde that exists in the current directory.
+
+c. Fixed a bug that caused a file descriptor leak when performing
+ redirections attached to a compound command.
+
+d. Fixed a bug that caused expansions of $@ and $* to not exit the shell if
+ the -u option was enabled and there were no posititional parameters.
+
+e. Fixed a bug that resulted in bash not terminating immediately if a
+ terminating signal was received while performing output.
+
+f. Fixed a bug that caused the shell to crash after creating 256 process
+ substitutions during word completion.
+
+2. Changes to Readline
+
+a. Fixed a bug that caused redisplay errors when using prompts with invisible
+ characters and numeric arguments to a command in a multibyte locale.
+
+b. Fixed a bug that caused redisplay errors when using prompts with invisible
+ characters spanning more than two physical screen lines.
+
+------------------------------------------------------------------------------
+This document details the changes between this version, bash-4.0-beta,
+and the previous version, bash-4.0-alpha.
+
+1. Changes to Bash
+
+a. Fixed a typo that caused a variable to be used before initialization
+ while parsing Posix-style command substitutions.
+
+b. Fixed a bug that caused stray ^? when the expansion of a parameter used
+ as part of a pattern removal expansion is empty, but part of a non-
+ empty string.
+
+c. Fixed a bug that could cause strings not converted to numbers by strtol
+ to be treated as if the conversion had been successful.
+
+d. The `return' builtin now accepts no options and requires a `--' before
+ a negative return value, as Posix requires.
+
+e. Fixed a bug that caused local variables to be created with the empty
+ string for a value rather than no value.
+
+f. Changed behavior so the shell now acts as if it received an interrupt
+ when a pipeline is killed by SIGINT while executing a list.
+
+g. Fixed a bug that caused `declare var' and `typeset var' to initialize
+ `var' to the empty string.
+
+h. Changed `bind' builtin to print a warning but proceed if invoked when
+ line editing is not active.
+
+i. Fixed a bug that caused the shell to exit when the `errexit' option is
+ set and a command in a pipeline returns a non-zero exit status.
+
+j. Fixed a bug that caused the shell to not run the exit trap in a command
+ run with `bash -c' under some circumstances.
+
+k. Fixed a bug that caused parser errors to occasionally not set $? when
+ running commands with `eval'.
+
+l. Fixed a bug that caused stray control characters when evaluating compound
+ array assignments containing $'\x7f' escapes.
+
+m. Fixed a bug that caused redirections involving file descriptor 10 as the
+ target to behave incorrectly.
+
+n. Fixed a bug that could cause memory to be freed multiple times when
+ assigning to COMP_WORDBREAKS.
+
+o. Fixed a bug that could cause NULL pointer dereferences when COMP_WORDBREAKS
+ was unset.
+
+2. Changes to Readline
+
+3. New Features in Bash
+
+a. A value of 0 for the -t option to `read' now returns success if there is
+ input available to be read from the specified file descriptor.
+
+b. CDPATH and GLOBIGNORE are ignored when the shell is running in privileged
+ mode.
+
+c. New bindable readline functions shell-forward-word and shell-backward-word,
+ which move forward and backward words delimited by shell metacharacters
+ and honor shell quoting.
+
+d. New bindable readline functions shell-backward-kill-word and shell-kill-word
+ which kill words backward and forward, but use the same word boundaries
+ as shell-forward-word and shell-backward-word.
+
+4. New Features in Readline
+
+a. If the kernel supports it, readline displays special characters
+ corresponding to a keyboard-generated signal when the signal is received.
+
+------------------------------------------------------------------------------
+This document details the changes between this version, bash-4.0-alpha,
+and the previous version, bash-3.2-release.
+
+1. Changes to Bash
+
+a. Fixed several bugs in old-style `` command substitution parsing, including
+ comment parsing and quoted string handling.
+
+b. Fixed problems parsing arguments to the [[ command's =~ regular expression
+ matching operator: metacharacter and whitespace parsing.
+
+c. Fixed a bug that caused the shell to inappropriately reuse high-numbered
+ file descriptors it used internally.
+
+d. Fixed a bug in pattern replacement word expansions that caused a `/' as
+ the first character of an expanded pattern to be mistaken for a global
+ replacement specifier.
+
+e. Fixed several problems with the asprintf and snprintf replacement functions
+ that caused hangs and crashes.
+
+f. Fixed a bug in the calculation of the current and previous job that caused
+ it to refer to incorrect jobs.
+
+g. Fixed a bug in the check for the validity of a hashed command pathname that
+ caused unnecessary hash table deletions and additions.
+
+h. Fixed a bug that caused child processes to inherit the wrong value for $!.
+
+i. Fixed a bug that caused `.' to fail to read and execute commands from non-
+ regular files such as devices or named pipes.
+
+j. Fixed a bug in printf formatting for the %x and %X expansions that occurred
+ on some systems.
+
+k. Fixed a bug that caused the shell to crash when creating temporary files if
+ $TMPDIR named a non-writable directory.
+
+l. Fixed a bug that caused the shell to ignore $TMPDIR when creating temporary
+ files under some circumstances.
+
+m. Fixed a bug that caused named pipes created by process substitution to not
+ be cleaned up.
+
+n. Fixed a bug that caused HISTTIMEFORMAT to not be honored when it appeared
+ in the initial shell environment.
+
+o. Fixed several bugs in the expansion of $* and $@ (quoted and unquoted)
+ when IFS is null or contains non-whitespace characters; the same changes
+ apply to arrays subscripted with * or @.
+
+p. Fixed several problems with pattern substitution expansions on the
+ positional parameters and arrays subscripted with * or @ that occurred
+ when $IFS was set to the empty string.
+
+q. Made a change to the default locale initialization code that should
+ result in better behavior from the locale-aware library functions.
+
+r. Fixed a bug that caused compacting the jobs list to drop jobs.
+
+s. Fixed a bug that caused jumps back to the top-level processing loop from
+ a builtin command to leave the shell in an inconsistent state.
+
+t. Fixed a bug that caused characters that would be escaped internally to be
+ doubled when escaped with a backslash.
+
+u. Fixed the initialization of mailboxes to not cause maildirs to be read
+ (and stat(2) called for every message file) at shell startup.
+
+v. Fixed a bug that caused the shell to not display $PS2 when the read builtin
+ reads a line continued with a backslash.
+
+w. Fixed a bug that caused errors in word splitting when $IFS contained
+ characters used for internal quoting.
+
+x. Fixed bugs that caused problems with output from shell builtins not being
+ completely displayed on some systems.
+
+y. Fixed a bug that caused output to be lost when a redirection is acting on
+ the shell's output file descriptor.
+
+z. Fixed bugs caused by shell builtins not checking for all write errors.
+
+aa. Fixed a problem that caused the shell to dump core if expansions on the
+ pattern passed to the pattern removal word expansions resulted in expansion
+ errors.
+
+bb. Fixed a bug that caused bash to loop infinitely after creating and
+ waiting for 4096 jobs.
+
+cc. Fixed a bug that caused bash to lose the status of a background job under
+ certain circumstances.
+
+dd. Fixed a bug that caused bash to not look in the temporary environment
+ when performing variable lookup under certain circumstances.
+
+ee. Fixed a bug that caused bash to close file descriptors greater than 10
+ when they were used in redirections.
+
+ff. Fixed a problem that caused the shell to attempt to read from the standard
+ input when called as `bash -i script'.
+
+gg. Fixed a memory leak and variable initialization problems when the -v option
+ was supplied to `printf' that could cause incorrect results.
+
+hh. Fixed a bug that caused the `read' builtin to count bytes when the -n option
+ was supplied, rather than (possibly multibyte) characters.
+
+ii. Fixed a bug when displaying a function due to not converting the function
+ to an external form.
+
+jj. Changed job control initialization to ensure that the shell has a tty
+ as its controlling terminal before enabling job control.
+
+kk. Fixed a bug with the `test' builtin that caused it to misinterpret
+ arguments beginning with `-' but containing more than one character.
+
+ll. Fixed bug that could cause the shell to dump core in certain cases where
+ a command sets the SIGINT disposition to the default.
+
+mm. Fixed a bug in the pattern replacement (affecting both word expansion
+ and the `fc' builtin) that occurred when the pattern and replacement
+ strings were empty.
+
+nn. Fixed a bug that caused an arithmetic evaluation error to disable all
+ further evaluation.
+
+oo. Fixed a bug in pathname expansion that caused it to interpret backslashes
+ in the pathname as quoting characters.
+
+pp. Fixed a bug in the replacement getcwd() implementation that could cause
+ memory to be overwritten.
+
+qq. When in Posix mode, the `ulimit' builtin now uses a block size of 512 for
+ the `-c' and `-f' options.
+
+rr. Brace expansion now allows process substitutions to pass through unchanged.
+
+ss. Fixed a problem in the command name completion code to avoid quoting
+ escaped special characters twice when the command name begins with a tilde.
+
+tt. Fixed a problem in the printf builtin that resulted in single-byte
+ output for the "'" escape, even when using multibyte characters.
+
+uu. Fixed a bug that caused the failure exit status to be lost when redirections
+ attached to a compound command failed.
+
+vv. Fixed a bug that caused the internal random number generator to not be
+ re-seeded correctly when creating a subshell.
+
+ww. Fixed a bug that could cause the bash replacement getcwd to overwrite
+ memory.
+
+xx. Fixed a bug that caused the shell to not receive SIGINT if it was sent
+ while the shell was waiting for a command substitution to terminate, and
+ make sure the exit status is correct when it does.
+
+yy. Fixed a bug that resulted in the second and subsequent children spawned
+ by a shell begun to run a command substitution being placed into the
+ wrong process group.
+
+zz. Fixed a bug that caused the results of successful tilde expansion to be
+ subject to pathname expansion and word splitting.
+
+aaa. Fixed a bug that could cause the shell to hang if it encountered an
+ error that caused it to jump back to the top processing loop during a
+ command substitution or `eval' command.
+
+bbb. Fixed a bug that caused the `read' builtin to use the tty's attributes
+ instead of those of the file descriptor passed with the -u option when
+ processing the -n and -d options.
+
+ccc. Fixed a bug that caused incorrect expansion of ${array[@]:foo} if the
+ first character of $IFS was not whitespace.
+
+ddd. Fixed a bug that occurred when scanning for the ending delimiter of a
+ ${parameter/pat/sub} expansion.
+
+eee. Fixed a bug that caused the shell to inappropriately expand command
+ substitutions in words when expanding directory names for completion.
+
+fff. Fixed a bug that caused the `fc' builtin to look too far back in the
+ history list under certain circumstances.
+
+ggg. Fixed a bug that caused a shell running in Posix mode to search $PWD for
+ a file specified as an argument to source/. when the file was not found
+ in $PATH.
+
+hhh. Fixed a bug that caused the shell to modify the case of a command word
+ found via command completion when the shell was performing case-
+ insensitive completion.
+
+iii. Fixed a bug that caused the shell to search $PATH for an argument to
+ source/. even when it contained a `/'.
+
+jjj. Fixed a bug that caused brace expansion to misorder expansions when the
+ locale did not have a collating order like aAbBcC...zZ.
+
+kkk. Fixed a bug that did not allow `set +o history' to have any effect when
+ run in a startup file or from a sourced file.
+
+lll. Fixed a bug with the precedence of the ?: conditional arithmetic operator.
+
+mmm. Fixed a bug that caused side effects of temporary variable assignments
+ to persist in the shell environment.
+
+nnn. Fixed a bug that caused the terminal to be left in non-canonical mode
+ when using editing commands that invoke the an editor on the current
+ command line.
+
+ooo. Fixed a bug that caused globbing characters and characters in $IFS to not
+ be quoted appropriately when displaying assignment statements.
+
+ppp. Fixed a bug that caused the `-e' option to be inherited when sourcing a
+ file or evaluating a command with `eval' even if the return value of the
+ command was supposed to be ignored.
+
+qqq. Fixed a bug that caused the shell to attempt to created variables with
+ invalid names if such names appeared in the initial environment.
+
+rrr. Fixed a bug with quote removal in strings where the final character is a
+ backslash.
+
+sss. Fixed a bug that caused the effects of special variables to persist even
+ when the variables were unset as part of the shell reinitializing itself
+ to execute a shell script.
+
+ttt. Fixed a bug that caused the history to not be saved after `history -c' or
+ `history -d' was executed until a sufficient number of commands had been
+ saved to the history.
+
+uuu. Bash now parses command substitutions according to Posix rules: parsing
+ the command contained in $() to find the closing delimiter.
+
+vvv. Fixed a bug that caused traps on SIGCHLD set in a SIGCHLD handler to
+ not persist.
+
+www. Fixed a bug that didn't allow SIGCHLD to interrupt the `wait' builtin
+ as Posix specifies.
+
+xxx. Invalid numeric arguments to shell builtins no longer cause the shell to
+ short-circuit any executing compound command.
+
+yyy. Fixed a bug that caused the exit status to be lost when `break' was
+ used to short-circuit a loop's execution.
+
+zzz. Fixed a bug that caused stray ^? characters to be left in expansions of
+ "${array[*]}".
+
+aaaa. Bash now prints better error messages for here documents terminated by
+ EOF and for identifying the incorrect token in an invalid arithmetic
+ expression.
+
+bbbb. Fixed a bug in the variable length word expansion that caused it to
+ incorrectly calculate the number of multibyte characters.
+
+cccc. Fixed a race condition that could result in the top-level shell setting
+ the terminal's process group to an incorrect value if the process
+ group was changed by a child of a child of the shell.
+
+dddd. Fixed a bug that caused here documents belonging to commands within a
+ compound command to be displayed in a syntactially-incorrect form, which
+ prevented them from being re-read as input.
+
+eeee. The shell displays more warnings about failures to set the locale.
+
+ffff. Fixed a bug that caused the body of a here-document to not be saved to
+ the history list.
+
+gggg. Fixed a bug that caused configure to incorrectly conclude that FreeBSD
+ had /dev/fd available, resulting in problems with process substitution.
+
+2. Changes to Readline
+
+a. Fixed a number of redisplay errors in environments supporting multibyte
+ characters.
+
+b. Fixed bugs in vi command mode that caused motion commands to inappropriately
+ set the mark.
+
+c. When using the arrow keys in vi insertion mode, readline allows movement
+ beyond the current end of the line (unlike command mode).
+
+d. Fixed bugs that caused readline to loop when the terminal has been taken
+ away and reads return -1/EIO.
+
+e. Fixed bugs in redisplay occurring when displaying prompts containing
+ invisible characters.
+
+f. Fixed a bug that caused the completion append character to not be reset to
+ the default after an application-specified completion function changed it.
+
+g. Fixed a problem that caused incorrect positioning of the cursor while in
+ emacs editing mode when moving forward at the end of a line while using
+ a locale supporting multibyte characters.
+
+h. Fixed an off-by-one error that caused readline to drop every 511th
+ character of buffered input.
+
+i. Fixed a bug that resulted in SIGTERM not being caught or cleaned up.
+
+j. Fixed redisplay bugs caused by multiline prompts with invisible characters
+ or no characters following the final newline.
+
+k. Fixed redisplay bug caused by prompts consisting solely of invisible
+ characters.
+
+l. Fixed a bug in the code that buffers characters received very quickly in
+ succession which caused characters to be dropped.
+
+m. Fixed a bug that caused readline to reference uninitialized data structures
+ if it received a SIGWINCH before completing initialzation.
+
+n. Fixed a bug that caused the vi-mode `last command' to be set incorrectly
+ and therefore unrepeatable.
+
+o. Fixed a bug that caused readline to disable echoing when it was being used
+ with an output file descriptor that was not a terminal.
+
+p. Readline now blocks SIGINT while manipulating internal data structures
+ during redisplay.
+
+q. Fixed a bug in redisplay that caused readline to segfault when pasting a
+ very long line (over 130,000 characters).
+
+r. Fixed bugs in redisplay when using prompts with no visible printing
+ characters.
+
+3. New Features in Bash
+
+a. When using substring expansion on the positional parameters, a starting
+ index of 0 now causes $0 to be prefixed to the list.
+
+b. The `help' builtin now prints its columns with entries sorted vertically
+ rather than horizontally.
+
+c. There is a new variable, $BASHPID, which always returns the process id of
+ the current shell.
+
+d. There is a new `autocd' option that, when enabled, causes bash to attempt
+ to `cd' to a directory name that is supplied as the first word of a
+ simple command.
+
+e. There is a new `checkjobs' option that causes the shell to check for and
+ report any running or stopped jobs at exit.
+
+f. The programmable completion code exports a new COMP_TYPE variable, set to
+ a character describing the type of completion being attempted.
+
+g. The programmable completion code exports a new COMP_KEY variable, set to
+ the character that caused the completion to be invoked (e.g., TAB).
+
+h. If creation of a child process fails due to insufficient resources, bash
+ will try again several times before reporting failure.
+
+i. The programmable completion code now uses the same set of characters as
+ readline when breaking the command line into a list of words.
+
+j. The block multiplier for the ulimit -c and -f options is now 512 when in
+ Posix mode, as Posix specifies.
+
+k. Changed the behavior of the read builtin to save any partial input received
+ in the specified variable when the read builtin times out. This also
+ results in variables specified as arguments to read to be set to the empty
+ string when there is no input available. When the read builtin times out,
+ it returns an exit status greater than 128.
+
+l. The shell now has the notion of a `compatibility level', controlled by
+ new variables settable by `shopt'. Setting this variable currently
+ restores the bash-3.1 behavior when processing quoted strings on the rhs
+ of the `=~' operator to the `[[' command.
+
+m. The `ulimit' builtin now has new -b (socket buffer size) and -T (number
+ of threads) options.
+
+n. The -p option to `declare' now displays all variable values and attributes
+ (or function values and attributes if used with -f).
+
+o. There is a new `compopt' builtin that allows completion functions to modify
+ completion options for existing completions or the completion currently
+ being executed.
+
+p. The `read' builtin has a new -i option which inserts text into the reply
+ buffer when using readline.
+
+q. A new `-E' option to the complete builtin allows control of the default
+ behavior for completion on an empty line.
+
+r. There is now limited support for completing command name words containing
+ globbing characters.
+
+s. Changed format of internal help documentation for all builtins to roughly
+ follow man page format.
+
+t. The `help' builtin now has a new -d option, to display a short description,
+ and a -m option, to print help information in a man page-like format.
+
+u. There is a new `mapfile' builtin to populate an array with lines from a
+ given file.
+
+v. If a command is not found, the shell attempts to execute a shell function
+ named `command_not_found_handle', supplying the command words as the
+ function arguments.
+
+w. There is a new shell option: `globstar'. When enabled, the globbing code
+ treats `**' specially -- it matches all directories (and files within
+ them, when appropriate) recursively.
+
+x. There is a new shell option: `dirspell'. When enabled, the filename
+ completion code performs spelling correction on directory names during
+ completion.
+
+y. The `-t' option to the `read' builtin now supports fractional timeout
+ values.
+
+z. Brace expansion now allows zero-padding of expanded numeric values and
+ will add the proper number of zeroes to make sure all values contain the
+ same number of digits.
+
+aa. There is a new bash-specific bindable readline function: `dabbrev-expand'.
+ It uses menu completion on a set of words taken from the history list.
+
+bb. The command assigned to a key sequence with `bind -x' now sets two new
+ variables in the environment of the executed command: READLINE_LINE_BUFFER
+ and READLINE_POINT. The command can change the current readline line
+ and cursor position by modifying READLINE_LINE_BUFFER and READLINE_POINT,
+ respectively.
+
+cc. There is a new &>> redirection operator, which appends the standard output
+ and standard error to the named file.
+
+dd. The parser now understands `|&' as a synonym for `2>&1 |', which redirects
+ the standard error for a command through a pipe.
+
+ee. The new `;&' case statement action list terminator causes execution to
+ continue with the action associated with the next pattern in the
+ statement rather than terminating the command.
+
+ff. The new `;;&' case statement action list terminator causes the shell to
+ test the next set of patterns after completing execution of the current
+ action, rather than terminating the command.
+
+gg. The shell understands a new variable: PROMPT_DIRTRIM. When set to an
+ integer value greater than zero, prompt expansion of \w and \W will
+ retain only that number of trailing pathname components and replace
+ the intervening characters with `...'.
+
+hh. There are new case-modifying word expansions: uppercase (^[^]) and
+ lowercase (,[,]). They can work on either the first character or
+ array element, or globally. They accept an optional shell pattern
+ that determines which characters to modify. There is an optionally-
+ configured feature to include capitalization operators.
+
+ii. The shell provides associative array variables, with the appropriate
+ support to create, delete, assign values to, and expand them.
+
+jj. The `declare' builtin now has new -l (convert value to lowercase upon
+ assignment) and -u (convert value to uppercase upon assignment) options.
+ There is an optionally-configurable -c option to capitalize a value at
+ assignment.
+
+kk. There is a new `coproc' reserved word that specifies a coprocess: an
+ asynchronous command run with two pipes connected to the creating shell.
+ Coprocs can be named. The input and output file descriptors and the
+ PID of the coprocess are available to the calling shell in variables
+ with coproc-specific names.
+
+4. New Features in Readline
+
+a. A new variable, rl_sort_completion_matches; allows applications to inhibit
+ match list sorting (but beware: some things don't work right if
+ applications do this).
+
+b. A new variable, rl_completion_invoking_key; allows applications to discover
+ the key that invoked rl_complete or rl_menu_complete.
+
+c. The functions rl_block_sigint and rl_release_sigint are now public and
+ available to calling applications who want to protect critical sections
+ (like redisplay).
+
+d. The functions rl_save_state and rl_restore_state are now public and
+ available to calling applications; documented rest of readline's state
+ flag values.
+
+e. A new user-settable variable, `history-size', allows setting the maximum
+ number of entries in the history list.
+
+f. There is a new implementation of menu completion, with several improvements
+ over the old; the most notable improvement is a better `completions
+ browsing' mode.
+
+g. The menu completion code now uses the rl_menu_completion_entry_function
+ variable, allowing applications to provide their own menu completion
+ generators.
+
+h. There is support for replacing a prefix of a pathname with a `...' when
+ displaying possible completions. This is controllable by setting the
+ `completion-prefix-display-length' variable. Matches with a common prefix
+ longer than this value have the common prefix replaced with `...'.
+
+i. There is a new `revert-all-at-newline' variable. If enabled, readline will
+ undo all outstanding changes to all history lines when `accept-line' is
+ executed.
+
+------------------------------------------------------------------------------
+This document details the changes between this version, bash-3.2-release,
+and the previous version, bash-3.2-beta.
+
+1. Changes to Bash
+
+a. Fixed a bug that caused the temporary environment passed to a command to
+ affect the shell's environment under certain circumstances.
+
+b. Fixed a bug in the printf builtin that caused the %q format specifier to
+ ignore empty string arguments.
+
+c. Improved multibyte character environment detection at configuration time.
+
+d. Fixed a bug in the read builtin that left spurious escape characters in the
+ input after processing backslashes when assigning to an array variable.
+
+2. Changes to Readline
+
+a. Fixed a redisplay bug that occurred in multibyte-capable locales when the
+ prompt was one character longer than the screen width.
+------------------------------------------------------------------------------
+This document details the changes between this version, bash-3.2-beta,
+and the previous version, bash-3.2-alpha.
+
+1. Changes to Bash
+
+a. Changed the lexical analyzer to treat locale-specific blank characters as
+ white space.
+
+b. Fixed a bug in command printing to avoid confusion between redirections and
+ process substitution.
+
+c. Fixed problems with cross-compiling originating from inherited environment
+ variables.
+
+d. Added write error reporting to printf builtin.
+
+e. Fixed a bug in the variable expansion code that could cause a core dump in
+ a multi-byte locale.
+
+f. Fixed a bug that caused substring expansion of a null string to return
+ incorrect results.
+
+g. BASH_COMMAND now retains its previous value while executing commands as the
+ result of a trap, as the documentation states.
+
+2. Changes to Readline
+
+a. Fixed a bug with prompt redisplay in a multi-byte locale to avoid redrawing
+ the prompt and input line multiple times.
+
+b. Fixed history expansion to not be confused by here-string redirection.
+
+c. Readline no longer treats read errors by converting them to newlines, as
+ it does with EOF. This caused partial lines to be returned from readline().
+
+------------------------------------------------------------------------------
+This document details the changes between this version, bash-3.2-alpha,
+and the previous version, bash-3.1-release.
+
+1. Changes to Bash
+
+a. Fixed a source bug that caused the minimal configuration to not compile.
+
+b. Fixed memory leaks in error handling for the `read' builtin.
+
+c. Changed the [[ and (( compound commands to set PIPESTATUS with their exit
+ status.
+
+d. Fixed some parsing problems with compound array assignments.
+
+e. Added additional configuration changes for: NetBSD (incomplete multibyte
+ character support)
+
+f. Fixed two bugs with local array variable creation when shadowing a variable
+ of the same name from a previous context.
+
+g. Fixed the `read' builtin to restore the correct set of completion functions
+ if a timeout occurs.
+
+h. Added code to defer the initialization of HISTSIZE (and its stifling of the
+ history list) until the history file is loaded, allowing a startup file to
+ override the default value.
+
+i. Tightened up the arithmetic expression parsing to produce better error
+ messages when presented with invalid operators.
+
+j. Fixed the cross-compilation support to build the signal list at shell
+ invocation rather than compile time if cross-compiling.
+
+k. Fixed multibyte support for non-gcc compilers (or compilers that do not
+ allow automatic array variable sizing based on a non-constant value).
+
+l. Several fixes to the code that manages the list of terminated jobs and
+ their exit statuses, and the list of active and recently-terminated jobs
+ to avoid pid aliasing/wraparound and allocation errors.
+
+m. Fixed a problem that allowed scripts to die due to SIGINT while waiting
+ for children, even when started in the background or otherwise ignoring
+ SIGINT.
+
+n. Fixed a bug that caused shells invoked as -/bin/bash from not being
+ recognized as login shells.
+
+o. Fixed a problem that caused shells in the background to give the terminal
+ to a process group other than the foreground shell process group.
+
+p. Fixed a problem with extracting the `varname' in ${#varname}.
+
+q. Fixed the code that handles SIGQUIT to not exit immediately -- thereby
+ calling functions that may not be called in a signal handler context --
+ but set a flag and exit afterward (like SIGINT).
+
+r. Changed the brace expansion code to skip over braces that don't begin a
+ valid matched brace expansion construct.
+
+s. Fixed `typeset' and `declare' to not require that their shell function
+ operands to be valid shell identifiers.
+
+t. Changed `test' to use access(2) with a temporary uid/euid swap when testing
+ file attributes and running setuid, and access(2) in most other cases.
+
+u. Changed completion code to not attempt command name completion on a line
+ consisting solely of whitespace when no_empty_command_completion is set.
+
+v. The `hash' builtin now prints nothing in posix mode when the hash table is
+ empty, and prints a message to that effect to stdout instead of stderr
+ when not in posix mode.
+
+w. Fixed a bug in the extended pattern matching code that caused it to fail to
+ match periods with certain patterns.
+
+x. Fixed a bug that caused the shell to dump core when performing filename
+ generation in directories with thousands of files.
+
+y. Returned to the original Bourne shell rules for parsing ``: no recursive
+ parsing of embedded quoted strings or ${...} constructs.
+
+z. The inheritence of the DEBUG, RETURN, and ERR traps is now dependent only
+ on the settings of the `functrace' and `errtrace' shell options, rather
+ than whether or not the shell is in debugging mode.
+
+aa. Fixed a problem with $HOME being converted to ~ in the expansion of
+ members of the DIRSTACK array.
+
+bb. Fixed a problem with quoted arguments to arithmetic expansions in certain
+ constructs.
+
+cc. The command word completion code now no longer returns matching directories
+ while searching $PATH.
+
+dd. Fixed a bug with zero-padding and precision handling in snprintf()
+ replacement.
+
+ee. Fixed a bug that caused the command substitution code not to take embedded
+ shell comments into account.
+
+ff. Fixed a bug that caused $((...);(...)) to be misinterpreted as an
+ arithmetic substitution.
+
+gg. Fixed a bug in the prompt expansion code that inappropriately added a
+ \001 before a \002 under certain circumstances.
+
+hh. Fixed a bug that caused `unset LANG' to not properly reset the locale
+ (previous versions would set the locale back to what it was when bash
+ was started rather than the system's "native" locale).
+
+ii. Fixed a bug that could cause file descriptors > 10 to not be closed even
+ when closed explicitly by a script.
+
+jj. Fixed a bug that caused single quotes to be stripped from ANSI-C quoting
+ inside double-quoted command substitutions.
+
+kk. Fixed a bug that could cause core dumps when `return' was executed as the
+ last element of a pipeline inside a shell function.
+
+ll. Fixed a bug that caused DEBUG trap strings to overwrite commands stored in
+ the jobs list.
+
+2. Changes to Readline
+
+a. Fixed a problem that caused segmentation faults when using readline in
+ callback mode and typing consecutive DEL characters on an empty line.
+
+b. Fixed several redisplay problems with multibyte characters, all having to
+ do with the different code paths and variable meanings between single-byte
+ and multibyte character redisplay.
+
+c. Fixed a problem with key sequence translation when presented with the
+ sequence \M-\C-x.
+
+d. Fixed a problem that prevented the `a' command in vi mode from being
+ undone and redone properly.
+
+e. Fixed a problem that prevented empty inserts in vi mode from being undone
+ properly.
+
+f. Fixed a problem that caused readline to initialize with an incorrect idea
+ of whether or not the terminal can autowrap.
+
+g. Fixed output of key bindings (like bash `bind -p') to honor the setting of
+ convert-meta and use \e where appropriate.
+
+h. Changed the default filename completion function to call the filename
+ dequoting function if the directory completion hook isn't set. This means
+ that any directory completion hooks need to dequote the directory name,
+ since application-specific hooks need to know how the word was quoted,
+ even if no other changes are made.
+
+i. Fixed a bug with creating the prompt for a non-interactive search string
+ when there are non-printing characters in the primary prompt.
+
+j. Fixed a bug that caused prompts with invisible characters to be redrawn
+ multiple times in a multibyte locale.
+
+k. Fixed a bug that could cause the key sequence scanning code to return the
+ wrong function.
+
+l. Fixed a problem with the callback interface that caused it to fail when
+ using multi-character keyboard macros.
+
+m. Fixed a bug that could cause a core dump when an edited history entry was
+ re-executed under certain conditions.
+
+n. Fixed a bug that caused readline to reference freed memory when attmpting
+ to display a portion of the prompt.
+
+3. New Features in Bash
+
+a. Changed the parameter pattern replacement functions to not anchor the
+ pattern at the beginning of the string if doing global replacement - that
+ combination doesn't make any sense.
+
+b. When running in `word expansion only' mode (--wordexp option), inhibit
+ process substitution.
+
+c. Loadable builtins now work on MacOS X 10.[34].
+
+d. Shells running in posix mode no longer set $HOME, as POSIX requires.
+
+e. The code that checks for binary files being executed as shell scripts now
+ checks only for NUL rather than any non-printing character.
+
+f. Quoting the string argument to the [[ command's =~ operator now forces
+ string matching, as with the other pattern-matching operators.
+
+4. New Features in Readline
+
+a. Calling applications can now set the keyboard timeout to 0, allowing
+ poll-like behavior.
+
+b. The value of SYS_INPUTRC (configurable at compilation time) is now used as
+ the default last-ditch startup file.
+
+c. The history file reading functions now allow windows-like \r\n line
+ terminators.
+
+------------------------------------------------------------------------------
+This document details the changes between this version, bash-3.1-release,
+and the previous version, bash-3.1-rc2.
+
+1. Changes to Readline
+
+a. Several changes to the multibyte redisplay code to fix problems with
+ prompts containing invisible characters.
+
+------------------------------------------------------------------------------
+This document details the changes between this version, bash-3.1-rc2,
+and the previous version, bash-3.1-rc1.
+
+1. Changes to Bash
+
+a. Fixed a bug that caused a DEBUG trap to overwrite a command string that's
+ eventually attached to a background job.
+
+b. Changed some code so that filenames with leading tildes with spaces in the
+ name aren't tilde-expanded by the bash completion code.
+
+c. Fixed a bug that caused the pushd builtin to fail to change to
+ directories with leading `-'.
+
+d. Fixed a small memory leak in the programmable completion code.
+
+2. Changes to Readline
+
+a. Fixed a redisplay bug caused by moving the cursor vertically to a line
+ with invisible characters in the prompt in a multibyte locale.
+
+b. Fixed a bug that could cause the terminal special chars to be bound in the
+ wrong keymap in vi mode.
+
+3. New Features in Bash
+
+a. If compiled for strict POSIX conformance, LINES and COLUMNS may now
+ override the true terminal size.
+
+4. New Features in Readline
+
+a. A new external application-controllable variable that allows the LINES
+ and COLUMNS environment variables to set the window size regardless of
+ what the kernel returns.
+
+------------------------------------------------------------------------------
+This document details the changes between this version, bash-3.1-rc1,
+and the previous version, bash-3.1-beta1.
+
+1. Changes to Bash
+
+a. Fixed a bug that could cause core dumps due to accessing the current
+ pipeline while in the middle of modifying it.
+
+b. Fixed a bug that caused pathnames with backslashes still quoting characters
+ to be passed to opendir().
+
+c. Command word completion now obeys the setting of completion-ignore-case.
+
+d. Fixed a problem with redirection that caused file descriptors greater than
+ 2 to be inappropriately marked as close-on-exec.
+
+e. In Posix mode, after `wait' is called to wait for a particular process
+ explicitly, that process is removed from the list of processes known to
+ the shell, and subsequent attempts to wait for it return errors.
+
+f. Fixed a bug that caused extended pattern matching to incorrectly scan
+ backslash-escaped pattern characters.
+
+g. Fixed a synchronization problem that could cause core dumps when handling
+ a SIGWINCH.
+
+h. Fixed a bug that caused an unmatched backquote to be accepted without an
+ error when processing here documents.
+
+i. Fixed a small memory leak in the `cd' builtin.
+
+j. Fix for MacOS X so it gets the values for the HOSTTYPE, MACHTYPE, and
+ OSTYPE variables at build time, to support universal binaries.
+
+k. Fixed a bug that could cause an exit trap to return the exit status of
+ the trap command rather than the status as it was before the trap was
+ run as the shell's exit status.
+
+2. New Features in Bash
+
+3. Changes to Readline
+
+a. Fixed a bug that caused reversing the incremental search direction to
+ not work correctly.
+
+b. Fixed the vi-mode `U' command to only undo up to the first time insert mode
+ was entered, as Posix specifies.
+
+c. Fixed a bug in the vi-mode `r' command that left the cursor in the wrong
+ place.
+
+4. New Features in Readline
+
+a. New application-callable auxiliary function, rl_variable_value, returns
+ a string corresponding to a readline variable's value.
+
+b. When parsing inputrc files and variable binding commands, the parser
+ strips trailing whitespace from values assigned to boolean variables
+ before checking them.
+
+
+------------------------------------------------------------------------------
+This document details the changes between this version, bash-3.1-beta1,
+and the previous version, bash-3.1-alpha1.
+
+1. Changes to Bash
+
+a. Added some system-specific signal names.
+
+b. Fixed a typo in the ulimit builtin to make `x' the right option to
+ maniuplate the limit on file locks.
+
+c. Fixed a problem with using += to append to index 0 of an array variable
+ when not using subscript syntax.
+
+d. A few changes to configure.in to remove calls to obsolete or outdated
+ macros.
+
+e. Make sure changes to variables bash handles specially (e.g., LC_ALL) are
+ made when the variable is set in the temporary environment to a command.
+
+f. Make sure changes to variables bash handles specially (e.g., LC_ALL) are
+ made when the variable is modified using `printf -v'.
+
+g. The export environment is now remade on cygwin when HOME is changed, so
+ DLLs bash is linked against pick up the new value. This fixes problems
+ with tilde expansion when linking against and already-installed readline.
+
+h. Small fix to the logic for performing tilde expansion in posix mode, so
+ expansion on the right-hand side of an assignment statement takes place.
+
+i. Fixed a bug that prevented redirections associated with a shell function
+ from being executed when in a subshell.
+
+j. Fixed `source' and `.' builtins to not require an executable file when
+ searching $PATH for a file to source.
+
+k. Fixed a bug that caused incorrect word splitting in a function when IFS
+ was declared local, then unset.
+
+l. Fixed a problem with the `kill' builtin that prevented sending signals
+ to a process group under certain circumstances when providing a pid < 0.
+
+m. When in POSIX mode, `pwd' now checks that the value it prints is the same
+ directory as `.', even when displaying $PWD.
+
+n. Fixed a problem with the `read' builtin when reading a script from standard
+ input and reading data from the same file.
+
+o. Fixed a problem with the `type' and `command' builtins that caused absolute
+ pathnames to be displayed incorrectly.
+
+p. Some changes to the `bg' builtin for POSIX conformance.
+
+q. The `fc' builtin now removes the `fc' command that caused it to invoke an
+ editor on specified history entries from the history entirely, rather than
+ simply ignoring it.
+
+r. When in POSIX mode, the `v' command in vi editing mode simply invokes vi
+ on the current command, rather than checking $FCEDIT and $EDITOR.
+
+s. Fixed a small memory leak in the pathname canonicalization code.
+
+t. Fixed a bug that caused the expanded value of a $'...' string to be
+ incorrectly re-quoted if it occurred within a double-quoted ${...}
+ parameter expansion.
+
+u. Restored default emacs-mode key binding of M-TAB to dynamic-complete-history.
+
+v. Fixed a bug that caused core dumps when interrupting loops running builtins
+ on some systems.
+
+w. Make sure that some of the functions bash provides replacements for are
+ not cpp defines.
+
+x. The code that scans embedded commands for the parser (`...` and $(...)) is
+ now more aware of embedded comments and their effect on quoted strings.
+
+y. Changed the `-n' option to the `history' builtin to not reset the number of
+ history lines read in the current session after reading the new lines from
+ the history file if the history is being appended when it is written to
+ the file, since the appending takes care of the problem that the adjustment
+ was intended to solve.
+
+z. Improved the error message displayed when a shell script fails to execute
+ because the environment and size of command line arguments are too large.
+
+aa. A small fix to make sure that $HISTCMD is evaluated whenever the shell is
+ saving commands to the history list, not just when HISTSIZE is defined.
+
+2. Changes to Readline
+
+a. The `change-case' command now correctly changes the case of multibyte
+ characters.
+
+b. Changes to the shared library construction scripts to deal with Windows
+ DLL naming conventions for Cygwin.
+
+c. Fixed the redisplay code to avoid core dumps resulting from a poorly-timed
+ SIGWINCH.
+
+d. Fixed the non-incremental search code in vi mode to dispose of any current
+ undo list when copying a line from the history into the current editing
+ buffer.
+
+e. The variable assignment code now ignores whitespace at the end of lines
+ when assigning to boolean variables.
+
+f. The `C-w' binding in incremental search now understands multibyte
+ characters.
+
+3. New Features in Bash
+
+a. A new configuration option, `--enable-strict-posix-default', which will
+ build bash to be POSIX conforming by default.
+
+4. New Features in Readline
+
+a. If the rl_completion_query_items is set to a value < 0, readline never
+ asks the user whether or not to view the possible completions.
+
+------------------------------------------------------------------------------
+This document details the changes between this version, bash-3.1-alpha1,
+and the previous version, bash-3.0-release.
+
+1. Changes to Bash
+
+a. Fixed a bug that caused bash to crash if referencing an unset local array.
+
+b. Fixed a problem that caused tilde expansion to not be performed before
+ attempting globbing word completion.
+
+c. Fixed an incompatibility so that a first argument to trap that's a valid
+ signal number will be trated as a signal rather than a command to execute.
+
+d. Fixed ${#word} expansion to correctly compute the length of a string
+ containing multibyte characters.
+
+e. Fixed a bug that caused bash to not pass the correct flags for signal
+ disposition to child processes.
+
+f. Fixed a bug that caused `fc -l' to list one too many history entries.
+
+g. Some fixes to `fc' for POSIX conformance.
+
+h. Some fixes to job status display for POSIX conformance.
+
+i. Fixed a bug that caused `command -v' to display output if a command was not
+ found -- it should be silent.
+
+j. In POSIX mode, `type' and `command -[vV]' do not report non-executable
+ files, even if the shell will attempt to execute them.
+
+k. Fixed a bug that caused the `==' operator to the [[ command to not attempt
+ extended pattern matching.
+
+l. Fixed the brace expansion code to handle characters whose value exceeds 128.
+
+m. Fixed `printf' to handle strings with a leading `\0' whose length is
+ non-zero.
+
+n. Fixed a couple of problems with brace expansion where `${' was handled
+ incorrectly.
+
+o. Fixed off-by-one error when calculating the upper bound of `offset' when
+ processing the ${array[@]:offset:length} expansion.
+
+p. System-specific configuration changes for: FreeBSD 5.x, Interix, MacOS X
+ 10.4, Linux 2.4+ kernels, Linux 3.x kernels, Dragonfly BSD, QNX 6.x,
+ Cygwin
+
+q. Fixed a bug that caused the shell to ignore the status of the rightmost
+ command in a pipeline when the `pipefail' option was enabled.
+
+r. Fixed a completion bug that caused core dumps when expanding a directory
+ name.
+
+s. Fixed a bug that prevented `hash -d' from removing commands from the hash
+ table.
+
+t. Fixed word splitting to avoid really bad quadratic performance when
+ expanding long lists.
+
+u. Fixed a bug that caused negative offsets in substring expansion to use the
+ wrong values.
+
+v. Fixed a bug in printf that caused it to not return failure on write errors.
+
+w. Fixed a bug that caused commands in subshells to not be properly timed.
+
+x. The shell parser no longer attempts to parse a compound assignment specially
+ unless in a position where an assignment statement is acceptable or parsing
+ arguments to a builtin that accepts assignment statements.
+
+y. Fixed a problem that caused a `case' statement to be added to the history
+ incorrectly as a single command if the `case word' was on one line and the
+ `in' on another.
+
+z. Fixed a problem that caused internal shell quoting characters to be
+ incorrectly quoted with backslashes under some circumstances.
+
+aa. The shell now performs correct word splitting when IFS contains multibyte
+ characters.
+
+bb. The mail checking code now resets the cached file information if the size
+ drops to 0, even if the times don't change.
+
+cc. A completed command name that is found in $PATH as well as the name of a
+ directory in the current directory no longer has a slash appended in certain
+ circumstances: a single instance found in $PATH when `.' is not in $PATH,
+ and multiple instances found in $PATH, even when `.' is in $PATH.
+
+dd. Incorporated tilde expansion into the word expansion code rather than as a
+ separately-called function, fixing some cases where it was performed
+ inappropriately (e.g., after the second `=' in an assignment statement or
+ in a double-quoted parameter expansion).
+
+ee. Fixed several bugs encountered when parsing compound assignment statements,
+ so that compound assignments appearing as arguments to builtins are no
+ longer double-expanded.
+
+ff. Fixed a bug in the command execution code that caused asynchronous commands
+ containing command substitutions to not put the terminal in the wrong
+ process group.
+
+gg. Bash now handles the case where the WCONTINUED flag causes waitpid() to
+ return -1/EINVAL at runtime as well as configuration time.
+
+hh. Fixed parser to generate an error when the pipeline `argument' to `!' or
+ `time' is NULL.
+
+ii. The shell now takes a little more care when manipulating file descriptors
+ greater than 9 with the `exec' builtin.
+
+jj. Fixed a bug that caused variable assignments preceding the `command' builtin
+ preceding a special builtin to be preserved after the command completed in
+ POSIX mode.
+
+kk. Fixed a bug that allowed variables beginning with a digit to be created.
+
+ll. Fixed a bug that caused a \<newline> to be removed when parsing a $'...'
+ construct.
+
+mm. A shell whose name begins with `-' will now be a restricted shell if the
+ remainder of the name indicates it should be restricted.
+
+nn. Fixed a bug that could cause a core dump if FUNCNAME were changed or unset
+ during a function's execution.
+
+oo. Fixed a bug that caused executing a `return' in a function to not execute
+ a RETURN trap. The RETURN trap is inherited by shell functions only if
+ function tracing is globally enabled or has been enabled for that function.
+
+pp. Fixed cases where var[@] was not handled exactly like var, when var is a
+ scalar variable.
+
+qq. Fixed a bug that caused the first character after a SIGINT to be discarded
+ under certain circumstances.
+
+rr. Fixed exit status code so that a suspended job returns 128+signal as its
+ exit status (preventing commands after it in `&&' lists from being
+ executed).
+
+ss. Fixed a bug that caused the shell parser state to be changed by executing
+ a shell function as a result of word completion.
+
+tt. Fixed a long-standing bug that caused '\177' characters in variable
+ values to be discarded when expanded in double-quoted strings.
+
+uu. Fixed a bug that caused $RANDOM to be re-seeded multiple times in a
+ subshell environment.
+
+vv. Extensive changes to the job management code to avoid the pid-reuse and
+ pid-aliasing problems caused by retaining the exit status of too many jobs,
+ but still retain as many background job statuses as POSIX requires.
+
+ww. Fixed a parser bug in processing \<newline> that caused things like
+
+ ((echo 5) \
+ (echo 6))
+
+ to not work correctly.
+
+xx. `pwd -P' now sets $PWD to a directory name containing no symbolic links
+ when in posix mode, as POSIX requires.
+
+yy. In posix mode, bash no longer sets $PWD to a name containing no symbolic
+ links if a directory is chosen from $CDPATH.
+
+zz. The word splitting code now treats an IFS character that is not space,
+ tab, or newline and any adjacent IFS white space as a single delimiter, as
+ SUSv3/XPG6 require.
+
+aaa. The `read' builtin now checks whether or not the number of fields read is
+ exactly the same as the number of variables instead of just assigning the
+ rest of the line (minus any trailing IFS white space) to the last
+ variable. This is what POSIX/SUS/XPG all require.
+
+bbb. Fixed a bug that caused `read' to always check whether or not fd 0 was a
+ pipe, even when reading from another file descriptor.
+
+ccc. Fixed a bug that caused short-circuiting of execution even if the return
+ value was being inverted.
+
+ddd. Fixed a bug that caused a core dump while decoding \W escapes in PS1 if
+ PWD was unset.
+
+eee. Fixed a bug in `read' that counted internal quoting characters for the
+ purposes of `read -n'.
+
+fff. Fixed a bug so that a function definition in a pipeline causes a child
+ process to be forked at the right time.
+
+ggg. Bash will not attempt to link against a readline library that doesn't
+ have rl_gnu_readline_p == 1.
+
+hhh. Fixed a bug that caused `read' to consume one too many characters when
+ reading a fixed number of characters and the Nth character is a backslash.
+
+iii. Fixed a bug that caused `unset' on variables in the temporary environment
+ to leave them set when `unset' completed.
+
+jjj. Fixed a bug that caused bash to close fd 2 if an `exec' failed and the
+ shell didn't exit.
+
+kkk. The completion code is more careful to not turn `/' or `///' into `//',
+ for those systems on which `//' has special meaning.
+
+lll. Fixed a bug that caused command substitution in asynchronous commands to
+ close the wrong file descriptors.
+
+mmm. The shell no longer prints status messages about terminated background
+ processes unless job control is active.
+
+nnn. Fixed a bug that prevented multiple consecutive invocations of `history -s'
+ from adding all the commands to the history list.
+
+ooo. Added a couple of changes to make arithmetic expansion more consistent in
+ all its contexts (still not perfect).
+
+ppp. Fixed a bug that caused the parser to occasionally not find the right
+ terminating "`" in an old-style command substitution.
+
+qqq. Fixed a bug that caused core dumps when the shell was reading its non-
+ interactive input from fd 0 and fd 0 was duplicated and restored using a
+ combination of `exec' (to save) and redirection (to restore).
+
+rrr. Fixed a problem that caused loops in sourced scripts to not be cleaned
+ up properly when a `return' is executed.
+
+sss. Change internal command substitution completion function to append a slash
+ to directory names in the command.
+
+2. Changes to Readline
+
+a. Fixed a bug that caused multiliine prompts to be wrapped and displayed
+ incorrectly.
+
+b. Fixed a bug that caused ^P/^N in emacs mode to fail to display the current
+ line correctly.
+
+c. Fixed a problem in computing the number of invisible characters on the first
+ line of a prompt whose length exceeds the screen width.
+
+d. Fixed vi-mode searching so that failure preserves the current line rather
+ than the last line in the history list.
+
+e. Fixed the vi-mode `~' command (change-case) to have the correct behavior at
+ end-of-line when manipulating multibyte characters.
+
+f. Fixed the vi-mode `r' command (change-char) to have the correct behavior at
+ end-of-line when manipulating multibyte characters.
+
+g. Fixed multiple bugs in the redisplay of multibyte characters: displaying
+ prompts longer than the screen width containing multibyte characters,
+
+h. Fix the calculation of the number of physical characters in the prompt
+ string when it contains multibyte characters.
+
+i. A non-zero value for the `rl_complete_suppress_append' variable now causes
+ no `/' to be appended to a directory name.
+
+j. Fixed forward-word and backward-word to work when words contained
+ multibyte characters.
+
+k. Fixed a bug in finding the delimiter of a `?' substring when performing
+ history expansion in a locale that supports multibyte characters.
+
+l. Fixed a memory leak caused by not freeing the timestamp in a history entry.
+
+m. Fixed a bug that caused "\M-x" style key bindings to not obey the setting
+ of the `convert-meta' variable.
+
+n. Fixed saving and restoring primary prompt when prompting for incremental
+ and non-incremental searches; search prompts now display multibyte
+ characters correctly.
+
+o. Fixed a bug that caused keys originally bound to self-insert but shadowed
+ by a multi-character key sequence to not be inserted.
+
+p. Fixed code so rl_prep_term_function and rl_deprep_term_function aren't
+ dereferenced if NULL (matching the documentation).
+
+q. Extensive changes to readline to add enough state so that commands
+ requiring additional characters (searches, multi-key sequences, numeric
+ arguments, commands requiring an additional specifier character like
+ vi-mode change-char, etc.) work without synchronously waiting for
+ additional input.
+
+r. Lots of changes so readline builds and runs on MinGW.
+
+s. Readline no longer tries to modify the terminal settings when running in
+ callback mode.
+
+t. The Readline display code no longer sets the location of the last invisible
+ character in the prompt if the \[\] sequence is empty.
+
+3. New Features in Bash
+
+a. Bash now understands LC_TIME as a special variable so that time display
+ tracks the current locale.
+
+b. BASH_ARGC, BASH_ARGV, BASH_SOURCE, and BASH_LINENO are no longer created
+ as `invisible' variables and may not be unset.
+
+c. In POSIX mode, if `xpg_echo' option is enabled, the `echo' builtin doesn't
+ try to interpret any options at all, as POSIX requires.
+
+d. The `bg' builtin now accepts multiple arguments, as POSIX seems to specify.
+
+e. Fixed vi-mode word completion and glob expansion to perform tilde
+ expansion.
+
+f. The `**' mathematic exponentiation operator is now right-associative.
+
+g. The `ulimit' builtin has new options: -i (max number of pending signals),
+ -q (max size of POSIX message queues), and -x (max number of file locks).
+
+h. A bare `%' once again expands to the current job when used as a job
+ specifier.
+
+i. The `+=' assignment operator (append to the value of a string or array) is
+ now supported for assignment statements and arguments to builtin commands
+ that accept assignment statements.
+
+j. BASH_COMMAND now preserves its value when a DEBUG trap is executed.
+
+k. The `gnu_errfmt' option is enabled automatically if the shell is running
+ in an emacs terminal window.
+
+l. New configuration option: --single-help-strings. Causes long help text
+ to be written as a single string; intended to ease translation.
+
+m. The COMP_WORDBREAKS variable now causes the list of word break characters
+ to be emptied when the variable is unset.
+
+n. An unquoted expansion of $* when $IFS is empty now causes the positional
+ parameters to be concatenated if the expansion doesn't undergo word
+ splitting.
+
+o. Bash now inherits $_ from the environment if it appears there at startup.
+
+p. New shell option: nocasematch. If non-zero, shell pattern matching ignores
+ case when used by `case' and `[[' commands.
+
+q. The `printf' builtin takes a new option: -v var. That causes the output
+ to be placed into var instead of on stdout.
+
+r. By default, the shell no longer reports processes dying from SIGPIPE.
+
+s. Bash now sets the extern variable `environ' to the export environment it
+ creates, so C library functions that call getenv() (and can't use the
+ shell-provided replacement) get current values of environment variables.
+
+4. New Features in Readline
+
+a. The key sequence sent by the keypad `delete' key is now automatically
+ bound to delete-char.
+
+b. A negative argument to menu-complete now cycles backward through the
+ completion list.
+
+c. A new bindable readline variable: bind-tty-special-chars. If non-zero,
+ readline will bind the terminal special characters to their readline
+ equivalents when it's called (on by default).
+
+d. New bindable command: vi-rubout. Saves deleted text for possible
+ reinsertion, as with any vi-mode `text modification' command; `X' is bound
+ to this in vi command mode.
+
+------------------------------------------------------------------------------
+This document details the changes between this version, bash-3.0-release,
+and the previous version, bash-3.0-rc1.
+
+1. Changes to Bash
+
+a. Fixed a boundary overrun that could cause segmentation faults when the
+ completion code hands an incomplete construct to the word expansion
+ functions.
+
+b. Changed posix mode behavior so that an error in a variable assignment
+ preceding a special builtin causes a non-interactive shell to exit.
+
+c. Change the directory expansion portion of the completion code to not
+ expand embedded command substitutions if the directory name appears in
+ the file system.
+
+d. Fixed a problem that caused `bash -r' to turn on restrictions before
+ reading the startup files.
+
+e. Fixed a problem with the default operation of the `umask' builtin.
+
+2. Changes to Readline
+
+a. Fixed a problem with readline saving the contents of the current line
+ before beginning a non-interactive search.
+
+b. Fixed a problem with EOF detection when using rl_event_hook.
+
+c. Fixed a problem with the vi mode `p' and `P' commands ignoring numeric
+ arguments.
+
+------------------------------------------------------------------------------
+This document details the changes between this version, bash-3.0-rc1,
+and the previous version, bash-3.0-beta1.
+
+1. Changes to Bash
+
+a. Fixed a bug that caused incorrect behavior when referecing element 0 of
+ an array using $array, element 0 was unset, and `set -u' was enabled.
+
+b. System-specific changes for: SCO Unix 3.2, Tandem.
+
+c. Fixed a bug that caused inappropriate word splitting when a variable was
+ expanded within a double-quoted string that also included $@.
+
+d. Fixed a bug that caused `pwd' to not display anything in physical mode
+ when the file system had changed underneath the shell.
+
+e. Fixed a bug in the pre- and post- increment and decrement parsing in the
+ expression evaluator that caused errors when the operands and corresponding
+ operators were separated by whitespace.
+
+f. Fixed a bug that caused `history -p' to add an entry to the history list,
+ counter to the documentation. (Keeps the history expansions invoked by
+ emacs-mode command line editing from doing that as well.)
+
+g. Fixed a bug that could cause a core dump if `cd' is asked to print out a
+ pathname longer than PATH_MAX characters.
+
+h. Fixed a bug that caused jobs to be put into the wrong process group under
+ some circumstances after enabling job control with `set -m'.
+
+i. `unalias' now returns failure if no alias name arguments are supplied.
+
+j. Documented the characters not allowed to appear in an alias name.
+
+k. $* is no longer expanded as if in double quotes when it appears in the
+ body of a here document, as the SUS seems to require.
+
+l. The `bashbug' script now uses a directory in $TMPDIR for exclusive
+ access rather than trying to guess how the underlying OS provides for
+ secure temporary file creation.
+
+m. Fixed a few problems with `cd' and `pwd' when asked to operate on pathnames
+ longer than PATH_MAX characters.
+
+n. Fixed a memory leak caused when creating multiple local array variables
+ with identical names.
+
+o. Fixed a problem with calls to getcwd() so that bash now operates better
+ when the full pathname to the current directory is longer than PATH_MAX
+ bytes.
+
+p. The `trap' builtin now reports an error if a single non-signal argument
+ is specified.
+
+q. Fixed a bug that caused `umask' to not work correctly when presented
+ with a mask of all 0s.
+
+r. When `getopts' reaches the end of options, OPTARG is unset, as POSIX
+ appears to specify.
+
+s. Interactive mode now depends on whether or not stdin and stderr are
+ connected to a tty; formerly it was stdin and stdout. POSIX requires
+ this.
+
+t. Fixed vi-mode completion to work more as POSIX specifies (e.g., doing the
+ right kind of filename generation).
+
+2. Changes to Readline
+
+a. Fixed a problem that could cause readline to refer to freed memory when
+ moving between history lines while doing searches.
+
+b. Improvements to the code that expands and displays prompt strings
+ containing multibyte characters.
+
+c. Fixed a problem with vi-mode not correctly remembering the numeric argument
+ to the last `c'hange command for later use with `.'.
+
+d. Fixed a bug in vi-mode that caused multi-digit count arguments to work
+ incorrectly.
+
+e. Fixed a problem in vi-mode that caused the last text modification command
+ to not be remembered across different command lines.
+
+f. Fixed problems with changing characters and changing case at the end of
+ the line.
+
+3. New Features in Bash
+
+a. The `jobs', `kill', and `wait' builtins now accept job control notation
+ even if job control is not enabled.
+
+b. The historical behavior of `trap' that allows a missing `action' argument
+ to cause each specified signal's handling to be reset to its default is
+ now only supported when `trap' is given a single non-option argument.
+
+4. New Features in Readline
+
+a. When listing completions, directories have a `/' appended if the
+ `mark-directories' option has been enabled.
+
+------------------------------------------------------------------------------
+This document details the changes between this version, bash-3.0-beta1,
+and the previous version, bash-3.0-alpha.
+
+1. Changes to Bash
+
+a. Fixes to build correctly when arrays are not compiled into the shell.
+
+b. Fixed command substitution to run any exit trap defined in the command
+ substitution before returning; the exit trap is not inherited from the
+ calling shell.
+
+c. Fixes to process group synchronization code so that every child process
+ attempts to set the terminal's process group; fixes some synchronization
+ problems on Linux kernels that schedule the child to always run before
+ the parent.
+
+d. Fixed processing of octal and hex constants in printf builtin for POSIX.2
+ compliance.
+
+e. Fixed a couple of core dumps in the pattern removal code.
+
+f. Fixes to the array subrange extraction code to deal better with sparse
+ arrays.
+
+g. Parser errors and other errors that result in the shell exiting now cause
+ the exit trap to be run.
+
+h. Change the command substitution completion functions to not append any
+ closing quote, because it would be inserted a closing "`" or ")".
+
+i. Fix history initialization so assignments to $histchars made in startup
+ files are honored.
+
+j. If an exit trap does not contain a call to `exit', the shell now uses
+ the exit status of the last command executed before the trap as the exit
+ status of the shell.
+
+k. The parser now prompts with $PS2 if it reads a newline while parsing a
+ compound array assignment statement.
+
+l. When performing a compound array assignment, the parser doesn't treat
+ words of the form [index]=value as assignments if they're the result of
+ expansions.
+
+m. Fixed a bug that caused `return' executed in a trap command to make the
+ shell think it was still running the trap.
+
+n. Fixed the value of errno set by the pathname canonicalization functions.
+
+o. Changed the grammar so that `time' alone on a line times a null command
+ rather than being a syntax error.
+
+p. The pattern substitution code no longer performs quote removal on the
+ pattern before trying to match it, as the pattern removal functions do.
+
+q. Fixed a bug that could cause core dumps when checking whether a quoted
+ command name was being completed.
+
+r. Fixes to the pattern removal and pattern replacement expansions to deal
+ with multibyte characters better (and faster).
+
+s. Fix to the substring expansion (${param:off[:len]}) to deal with (possibly
+ multibyte) characters instead of raw bytes.
+
+t. Fixed a bug that caused some key bindings set in an inputrc to be ignored
+ at shell startup.
+
+u. Fixed a bug that caused unsetting a local variable within a function to
+ not work correctly.
+
+v. Fixed a bug that caused invalid variables to be created when using
+ `read -a'.
+
+w. Fixed a bug that caused "$@" to expand incorrectly when used as the right
+ hand side of a parameter expansion such as ${word:="$@"} if the first
+ character of $IFS was not a space.
+
+x. Fixed a slight cosmetic problem when printing commands containing a
+ `>&word' redirection.
+
+y. Fixed a problem that could cause here documents to not be created correctly
+ if the system temporary directory did not allow writing.
+
+2. Changes to Readline
+
+a. Change to history expansion functions to treat `^' as equivalent to word
+ one, as the documention states.
+
+b. Some changes to the display code to improve display and redisplay of
+ multibyte characters.
+
+c. Changes to speed up the multibyte character redisplay code.
+
+d. Fixed a bug in the vi-mode `E' command that caused it to skip over the
+ last character of a word if invoked while point was on the word's
+ next-to-last character.
+
+e. Fixed a bug that could cause incorrect filename quoting when
+ case-insensitive completion was enabled and the word being completed
+ contained backslashes quoting word break characters.
+
+f. Fixed a bug in redisplay triggered when the prompt string contains
+ invisible characters.
+
+g. Fixed some display (and other) bugs encountered in multibyte locales
+ when a non-ascii character was the last character on a line.
+
+h. Fixed some display bugs caused by multibyte characters in prompt strings.
+
+i. Fixed a problem with history expansion caused by non-whitespace characters
+ used as history word delimiters.
+
+3. New Features in Bash
+
+a. printf builtin understands two new escape sequences: \" and \?.
+
+b. `echo -e' understands two new escape sequences: \" and \?.
+
+c. The GNU `gettext' package and libintl have been integrated; the shell's
+ messages can be translated into different languages.
+
+d. The `\W' prompt expansion now abbreviates $HOME as `~', like `\w'.
+
+e. The error message printed when bash cannot open a shell script supplied
+ as argument 1 now includes the name of the shell, to better identify
+ the error as coming from bash.
+
+4. New Features in Readline
+
+a. New application variable, rl_completion_quote_character, set to any
+ quote character readline finds before it calls the application completion
+ function.
+
+b. New application variable, rl_completion_suppress_quote, settable by an
+ application completion function. If set to non-zero, readline does not
+ attempt to append a closing quote to a completed word.
+
+c. New application variable, rl_completion_found_quote, set to a non-zero
+ value if readline determines that the word to be completed is quoted.
+ Set before readline calls any application completion function.
+
+d. New function hook, rl_completion_word_break_hook, called when readline
+ needs to break a line into words when completion is attempted. Allows
+ the word break characters to vary based on position in the line.
+
+e. New bindable command: unix-filename-rubout. Does the same thing as
+ unix-word-rubout, but adds `/' to the set of word delimiters.
+
+------------------------------------------------------------------------------
+This document details the changes between this version, bash-3.0-alpha,
+and the previous version, bash-2.05b-release.
+
+1. Changes to Bash
+
+a. Fixes so that the shell will compile without some of the default options
+ defined.
+
+b. Fixed an error message that did not pass enough arguments to printf.
+
+c. Fixed a bug that caused input redirection to a builtin inside a script
+ being read from standard input to result in the rest of the already-
+ read and buffered script to be discarded.
+
+d. Fixed a bug that caused subshell initialization to close the file
+ descriptor from which the shell was reading a script under certain
+ circumstances.
+
+e. Fixed a bug that caused the shell to not advance a string pointer over
+ a null wide character when doing string operations.
+
+f. Fixed the internal logout code so that shells that time out waiting for
+ input (using $TMOUT) run ~/.bash_logout.
+
+g. Portability and configuration changes for: cygwin, HP/UX, GNU/FreeBSD.
+
+h. The parser no longer adds implicit double quotes to ((...)) arithmetic
+ commands.
+
+i. The ((...)) arithmetic command evaluation code was fixed to not dump core
+ when the expanded string is null.
+
+j. The ((...)) arithmetic command evaluation code was fixed to not perform
+ variable assignments while expanding the expression.
+
+k. Fixed a bug that caused word splitting to be performed incorrectly when
+ IFS is set, but null.
+
+l. Fixed a bug in brace expansion that caused a quoted `$' preceding an
+ open brace to inhibit brace expansion.
+
+m. Fixed a bug that caused a leading `-' in the shell's name to cause it to
+ not be recognized as a restricted shell.
+
+n. Fixed a bug in the arithmetic evaluation code that could cause longjmps
+ to an invalid location and result in a core dump.
+
+o. Fixed a bug in the calculation of how many history lines are new in a
+ single shell session when reading new history lines from a file with
+ `history -n'.
+
+p. Fixed a bug in pathname canonicalization that caused the shell to dump
+ core when presented with a pathname longer than PATH_MAX.
+
+q. Fixed the parser so that it doesn't try to compare a char variable to
+ EOF, which fails when chars are unsigned.
+
+r. Fixed a bug in the simple command execution code that caused occasional
+ core dumps.
+
+s. The shell does a better job of saving any partial parsing state during
+ operations which cause a command to be executed while a line is being
+ entered and parsed.
+
+t. The completion code now splits words more like the expansion code when
+ $IFS is used to split.
+
+u. The locale code does a better job of recomputing the various locale
+ variable values when LC_ALL is unset.
+
+v. The programmable completion code does a better job of dequoting expanded
+ word lists before comparing them against the word to be matched.
+
+w. The shell no longer seg faults if the expanded value of $PS4 is null
+ and `set -x' is enabled.
+
+x. Fixed a bug that caused core dumps when a here string expanded to NULL.
+
+y. The mail checking code now makes sure the mailbox is bigger before
+ reporting the existence of new mail.
+
+z. The parser does not try to expand $'...' and $"..." when the appear
+ within double quotes unless the `extquote' option has been enabled with
+ `shopt'. For backwards compatibility, it is enabled by default.
+
+aa. Fixed a bug that caused `for x; do ...' and `select x; do ... to use
+ $@ instead of "$@" for the implicit list of arguments.
+
+bb. Fixed a bug that caused a subshell of a restricted shell (e.g., one
+ spawned to execute a pipeline) to not exit immediately if attempting
+ to use a command containing a slash.
+
+cc. Fixed a problem with empty replacements for a pattern that doesn't match
+ when performing ${param/word/} expansion.
+
+dd. Word expansions performed while expanding redirections no longer search
+ a command's temporary environment to expand variable values.
+
+ee. Improvements to the alias expansion code when expanding subsequent words
+ because an aliase's value ends with a space.
+
+ff. `cd -' now prints the current working directory after a successful chdir
+ even when the shell is not interactive, as the standard requires.
+
+gg. The shell does a better job of ensuring a child process dies of SIGINT
+ before resending SIGINT to itself.
+
+hh. The arithmetic expansion variable assignment code now does the right
+ thing when assigning to `special' variables like OPTIND.
+
+ii. When history expansion verification is enabled, the bash readline helper
+ functions that do history expansion on the current line don't print
+ the results.
+
+jj. Fixed bugs with multiple consecutive alias expansion when one of the
+ expansions ends with a space.
+
+kk. Fixed a problem in the programmable completion code that could cause core
+ dumps when trying to initialize a set of possible completions from a
+ list of variables.
+
+ll. The \[ and \] escape characters are now ignored when decoding the prompt
+ string if the shell is started with editing disabled.
+
+mm. Fixed a bug that could leave extra characters in a string when doing
+ quoted null character removal.
+
+nn. Command substitution and other subshell operations no longer reset the
+ line number (aids the bash debugger).
+
+oo. Better line number management when executing simple commands, conditional
+ commands, for commands, and select commands.
+
+pp. The globbing code now uses malloc, with its better failure properties,
+ rather than alloca().
+
+qq. Fixed a bug that caused expansions like #{a[2]:=value} to create the
+ appropriate array element instead of a variable named `a[2]'.
+
+rr. Fixed a bug in the handling of a `?(...)' pattern immediately following
+ a `*' when extglob is enabled.
+
+ss. Fixed a bug that caused a `return' invoked in an exit trap when exit is
+ invoked in a function to misbehave.
+
+tt. Fixed a bug that caused CTLESC and CTLNUL characters to not be escaped
+ by the internal shell string quoting functions.
+
+uu. Fixed a bug that caused quoted null characters in an expanded word list
+ to be inappropriately assigned to an array variable when using `read -a'.
+
+vv. Fixed a bug that caused redirections accompanying a null command to persist
+ in the current shell.
+
+ww. Fixed a bug that caused the prompt to be printed when the shell was
+ expanding a multiline alias.
+
+xx. Fixed a bug that resulted in core dumps when the completion for a command
+ changed the compspec.
+
+yy. Fixed a bug that caused evaluation of programmable completions to print
+ notifications of completed jobs.
+
+zz. Bash now disables line editing when $EMACS == `t' and $TERM == `dumb'
+ (which is what emacs shell windows do).
+
+aaa. In posix mode, `kill -l' causes signal names to be displayed without
+ a leading `SIG'.
+
+bbb. Clear error flag on standard output so it doesn't persist across multiple
+ builtin commands.
+
+ccc. In posix mode, `alias' displays alias values without the leading `alias',
+ so the output cannot be used as subsequent input.
+
+ddd. In posix mode, the `trap' builtin doesn't check whether or not its
+ first argument is a signal specification and revert the signal handling
+ to its original disposition if it is.
+
+eee. Fixed several bugs in the handling of "$*" and "${array[*]}" by the
+ pattern substitution and removal expansions.
+
+fff. Fixed several problems with the handling of ${array[@]}, ${array[*]},
+ $@, and $* by the indirect variable expansion code.
+
+ggg. Fixed a bug that did not allow `time' to be aliased.
+
+hhh. Improved the mail checking code so it won't check (and possibly cause an
+ NFS file system mount) until MAILPATH or MAIL is given a value -- there
+ is no default if DEFAULT_MAIL_DIRECTORY is not defined at compile time.
+ (It is computed by configure, but can be #undef'd in config-bot.h.)
+
+iii. If the `chkwinsize' option is enabled, the shell checks for window size
+ changes if a child process exits due to a signal.
+
+jjj. Removed the attempts to avoid adding a slash at the end of a completed
+ executable name if there was a directory with the same name in the
+ current directory.
+
+kkk. Fixed PATH lookup code so it treats the permission bits separately for
+ owner, group, and other, rather than checking them all.
+
+lll. Fixed the locale code to reset the parser's idea of the character class
+ <blank>, which controls how it splits tokens, when the locale changes.
+
+mmm. The shell now binds its special readline functions and key bindings only
+ if the user's inputrc file has not already bound them.
+
+nnn. The shell now reports on processes that dump core due to signals when
+ invoked as `-c command'.
+
+2. Changes to Readline
+
+a. Fixes to avoid core dumps because of null pointer references in the
+ multibyte character code.
+
+b. Fix to avoid infinite recursion caused by certain key combinations.
+
+c. Fixed a bug that caused the vi-mode `last command' to be set incorrectly.
+
+d. Readline no longer tries to read ahead more than one line of input, even
+ when more is available.
+
+e. Fixed the code that adjusts the point to not mishandle null wide
+ characters.
+
+f. Fixed a bug in the history expansion `g' modifier that caused it to skip
+ every other match.
+
+g. Fixed a bug that caused the prompt to overwrite previous output when the
+ output doesn't contain a newline and the locale supports multibyte
+ characters. This same change fixes the problem of readline redisplay
+ slowing down dramatically as the line gets longer in multibyte locales.
+
+h. History traversal with arrow keys in vi insertion mode causes the cursor
+ to be placed at the end of the new line, like in emacs mode.
+
+i. The locale initialization code does a better job of using the right
+ precedence and defaulting when checking the appropriate environment
+ variables.
+
+j. Fixed the history word tokenizer to handle <( and >( better when used as
+ part of bash.
+
+k. The overwrite mode code received several bug fixes to improve undo.
+
+l. Many speedups to the multibyte character redisplay code.
+
+m. The callback character reading interface should not hang waiting to read
+ keyboard input.
+
+n. Fixed a bug with redoing vi-mode `s' command.
+
+o. The code that initializes the terminal tracks changes made to the terminal
+ special characters with stty(1) (or equivalent), so that these changes
+ are reflected in the readline bindings. New application-callable function
+ to make it work: rl_tty_unset_default_bindings().
+
+p. Fixed a bug that could cause garbage to be inserted in the buffer when
+ changing character case in vi mode when using a multibyte locale.
+
+q. Fixed a bug in the redisplay code that caused problems on systems
+ supporting multibyte characters when moving between history lines when the
+ new line has more glyphs but fewer bytes.
+
+r. Undo and redo now work better after exiting vi insertion mode.
+
+s. Make sure system calls are restarted after a SIGWINCH is received using
+ SA_RESTART.
+
+t. Improvements to the code that displays possible completions when using
+ multibyte characters.
+
+u. Fixed a problem when parsing nested if statements in inputrc files.
+
+v. The completer now takes multibyte characters into account when looking for
+ quoted substrings on which to perform completion.
+
+w. The history search functions now perform better bounds checking on the
+ history list.
+
+3. New Features in Bash
+
+a. ANSI string expansion now implements the \x{hexdigits} escape.
+
+b. There is a new loadable `strftime' builtin.
+
+c. New variable, COMP_WORDBREAKS, which controls the readline completer's
+ idea of word break characters.
+
+d. The `type' builtin no longer reports on aliases unless alias expansion
+ will actually be performed.
+
+e. HISTCONTROL is now a colon-separated list of values, which permits
+ more extensibility and backwards compatibility.
+
+f. HISTCONTROL may now include the `erasedups' option, which causes all lines
+ matching a line being added to be removed from the history list.
+
+g. `configure' has a new `--enable-multibyte' argument that permits multibyte
+ character support to be disabled even on systems that support it.
+
+h. New variables to support the bash debugger: BASH_ARGC, BASH_ARGV,
+ BASH_SOURCE, BASH_LINENO, BASH_SUBSHELL, BASH_EXECUTION_STRING,
+ BASH_COMMAND
+
+i. FUNCNAME has been changed to support the debugger: it's now an array
+ variable.
+
+j. for, case, select, arithmetic commands now keep line number information
+ for the debugger.
+
+k. There is a new `RETURN' trap executed when a function or sourced script
+ returns (not inherited child processes; inherited by command substitution
+ if function tracing is enabled and the debugger is active).
+
+l. New invocation option: --debugger. Enables debugging and turns on new
+ `extdebug' shell option.
+
+m. New `functrace' and `errtrace' options to `set -o' cause DEBUG and ERR
+ traps, respectively, to be inherited by shell functions. Equivalent to
+ `set -T' and `set -E' respectively. The `functrace' option also controls
+ whether or not the DEBUG trap is inherited by sourced scripts.
+
+n. The DEBUG trap is run before binding the variable and running the action
+ list in a `for' command, binding the selection variable and running the
+ query in a `select' command, and before attempting a match in a `case'
+ command.
+
+o. New `--enable-debugger' option to `configure' to compile in the debugger
+ support code.
+
+p. `declare -F' now prints out extra line number and source file information
+ if the `extdebug' option is set.
+
+q. If `extdebug' is enabled, a non-zero return value from a DEBUG trap causes
+ the next command to be skipped, and a return value of 2 while in a
+ function or sourced script forces a `return'.
+
+r. New `caller' builtin to provide a call stack for the bash debugger.
+
+s. The DEBUG trap is run just before the first command in a function body is
+ executed, for the debugger.
+
+t. `for', `select', and `case' command heads are printed when `set -x' is
+ enabled.
+
+u. There is a new {x..y} brace expansion, which is shorthand for {x.x+1,
+ x+2,...,y}. x and y can be integers or single characters; the sequence
+ may ascend or descend; the increment is always 1.
+
+v. New ksh93-like ${!array[@]} expansion, expands to all the keys (indices)
+ of array.
+
+w. New `force_fignore' shopt option; if enabled, suffixes specified by
+ FIGNORE cause words to be ignored when performing word completion even
+ if they're the only possibilities.
+
+x. New `gnu_errfmt' shopt option; if enabled, error messages follow the `gnu
+ style' (filename:lineno:message) format.
+
+y. New `-o bashdefault' option to complete and compgen; if set, causes the
+ whole set of bash completions to be performed if the compspec doesn't
+ result in a match.
+
+z. New `-o plusdirs' option to complete and compgen; if set, causes directory
+ name completion to be performed and the results added to the rest of the
+ possible completions.
+
+aa. `kill' is available as a builtin even when the shell is built without
+ job control.
+
+bb. New HISTTIMEFORMAT variable; value is a format string to pass to
+ strftime(3). If set and not null, the `history' builtin prints out
+ timestamp information according to the specified format when displaying
+ history entries. If set, bash tells the history library to write out
+ timestamp information when the history file is written.
+
+cc. The [[ ... ]] command has a new binary `=~' operator that performs
+ extended regular expression (egrep-like) matching.
+
+dd. `configure' has a new `--enable-cond-regexp' option (enabled by default)
+ to enable the =~ operator and regexp matching in [[ ... ]].
+
+ee. Subexpressions matched by the =~ operator are placed in the new
+ BASH_REMATCH array variable.
+
+ff. New `failglob' option that causes an expansion error when pathname
+ expansion fails to produce a match.
+
+gg. New `set -o pipefail' option that causes a pipeline to return a failure
+ status if any of the processes in the pipeline fail, not just the last
+ one.
+
+4. New Features in Readline
+
+a. History expansion has a new `a' modifier equivalent to the `g' modifier
+ for compatibility with the BSD csh.
+
+b. History expansion has a new `G' modifier equivalent to the BSD csh `g'
+ modifier, which performs a substitution once per word.
+
+c. All non-incremental search operations may now undo the operation of
+ replacing the current line with the history line.
+
+d. The text inserted by an `a' command in vi mode can be reinserted with
+ `.'.
+
+e. New bindable variable, `show-all-if-unmodified'. If set, the readline
+ completer will list possible completions immediately if there is more
+ than one completion and partial completion cannot be performed.
+
+f. There is a new application-callable `free_history_entry()' function.
+
+g. History list entries now contain timestamp information; the history file
+ functions know how to read and write timestamp information associated
+ with each entry.
+
+h. Four new key binding functions have been added:
+
+ rl_bind_key_if_unbound()
+ rl_bind_key_if_unbound_in_map()
+ rl_bind_keyseq_if_unbound()
+ rl_bind_keyseq_if_unbound_in_map()
+
+------------------------------------------------------------------------------
+This document details the changes between this version, bash-2.05b-release,
+and the previous version, bash-2.05b-beta2.
+
+1. Changes to Bash
+
+a. Fixed an off-by-one error in the function that translates job
+ specifications.
+
+b. Note that we're running under Emacs and disable line editing if
+ $EMACS == `t'.
+
+------------------------------------------------------------------------------
+This document details the changes between this version, bash-2.05b-beta2,
+and the previous version, bash-2.05b-beta1.
+
+1. Changes to Bash
+
+a. Fixed the /= and %= arithmetic operators to catch division by zero.
+
+b. Added putenv, setenv, unsetenv to getenv replacement for completeness.
+
+c. Fixed a bug that could cause the -O expand_aliases invocation option
+ to not take effect.
+
+d. Fixed a problem with process substitution that resulted in incorrect
+ behavior when the number of process substitutions in an individual
+ command approached 64.
+
+2. Changes to Readline
+
+a. Fixed a problem with backward-char-search when on a system with support
+ for multibyte characters when running in a locale without any multibyte
+ characters.
+
+------------------------------------------------------------------------------
+This document details the changes between this version, bash-2.05b-beta1,
+and the previous version, bash-2.05b-alpha1.
+
+1. Changes to Bash
+
+a. Fixed a problem when parsing a POSIX.2 character class name while
+ evaluating a bracket expression containing multibyte characters.
+
+b. Changed the help text for `bind' to make it clear that any command
+ that may be placed in ~/.inputrc is a valid argument to `bind'.
+
+c. Added `help' builtin entries for `((', `[[', and arithmetic for.
+
+d. malloc updated again:
+ o slightly better overflow and underflow detection by putting the
+ chunk size at the beginning and end of the chunk and making
+ sure they match in free/realloc
+ o partial page allocated to make things page-aligned no longer
+ completely wasted
+ o block coalescing now enabled by default
+ o splitting and coalescing enabled for 32-byte chunks, the most
+ common size requested
+ o fixed a problem that resulted in spurious underflow messages and
+ aborts
+ o bin sizes are precomputed and stored in an array rather than
+ being computed at run time
+ o malloc will return memory blocks back to the system if the block
+ being freed is at the top of the heap and of sufficient size to
+ make it worthwhile
+ o malloc/free/realloc now inline memset instead of calling the
+ libc function; uses Duff's device for good performance
+
+e. Check for getservent(); make the service name completion code dependent
+ on its presence.
+
+f. Changed the readline callback that executes a command bound to a key
+ sequence to not save the executed command on the history list and to
+ save and restore the parsing state.
+
+g. Changes to lib/sh/snprintf.c: fixed some bugs in the `g' and `G'
+ floating point format display; implemented the "'" flag character
+ that turns on thousands' grouping; fixed behavior on systems where
+ MB_CUR_MAX does not evaluate to a constant.
+
+h. The `unset' builtin no longer returns a failure status when asked to
+ unset a previously-unset variable or function.
+
+i. Changes to the build system to make it easier to cross-compile bash
+ for different systems.
+
+j. Added `,' to the characters that are backslash-escaped during filename
+ completion, to avoid problems with complete-into-braces and RCS filenames
+ containing commas.
+
+k. Some changes to the multibyte character support code to avoid many calls
+ to strlen().
+
+l. Bash now correctly honors setting LANG to some value when LC_ALL does not
+ already have a value.
+
+m. Fixed a bug that could cause SIGSEGV when processing nested traps with
+ trap handlers.
+
+n. The `source/.' builtin now restores the positional parameters when it
+ returns unless they were changed using the `set' builtin during the file's
+ execution.
+
+o. Fixed a bug that caused a syntax error when a command was terminated by
+ EOF.
+
+2. New Features in Bash
+
+a. There is now support for placing the long help text into separate files
+ installed into ${datadir}/bash. Not enabled by default; can be turned
+ on with `--enable-separate-helpfiles' option to configure.
+
+b. All builtins that take operands accept a `--' pseudo-option, except
+ `echo'.
+
+c. The `echo' builtin now accepts \0xxx (zero to three octal digits following
+ the `0') in addition to \xxx (one to three octal digits) for SUSv3/XPG6/
+ POSIX.1-2001 compliance.
+
+3. Changes to Readline
+
+a. Fixed a small problem in _rl_insert_char with multibyte characters.
+
+b. Fixes from IBM for line wrapping problems when using multibyte characters.
+
+c. Fixed a problem which caused the display to be messed up when the last
+ line of a multi-line prompt (possibly containing invisible characters)
+ was longer than the screen width.
+
+d. Fixed a problem with the vi-mode `r' command that ocurred on systems with
+ support for multibyte characters when running in a locale without any
+ multibyte characters.
+
+------------------------------------------------------------------------------
+This document details the changes between this version, bash-2.05b-alpha1,
+and the previous version, bash-2.05a-release.
+
+1. Changes to Bash
+
+a. Some changes to work around inlining differences between compilers.
+
+b. Added more prototypes for internal shell typedefs, to catch argument
+ passing errors when using pointers to functions.
+
+c. The `cd' builtin now fails in posix mode when a valid directory cannot be
+ constructed from a relative pathname argument and the $PWD using pathname
+ canonicalization, and the -P option has not been supplied. Previously,
+ the shell would attempt to use what the user typed, leading to weird
+ values for $PWD and discrepancies between the value of $PWD and the
+ actual working directory.
+
+d. The `cd' builtin now resets $PWD when canonicalization fails but a chdir
+ to the pathname passed as an argument succeeds (when not in posix mode).
+
+e. The `fc' builtin has been fixed, as POSIX requires, to use the closest
+ history position in range when given an out-of-range argument.
+
+f. The history file loading code was changed to allow lines to be saved in
+ the history list from the shell startup files.
+
+g. `history -s args' now works better in compound commands.
+
+h. The tilde expansion code was fixed to better recognize when it's being
+ invoked in an assignment context, which enables expansion after `='
+ and `:'.
+
+i. Fixed the command name completion code so a slash is no longer appended
+ to a single match if there happens to be a directory with that name in
+ $PWD.
+
+j. Fixed compound array assignment to no longer perform alias expansion, to
+ allow reserved words as array members, and to not produce extra output
+ when the `-v' option had been enabled.
+
+k. Fixed the programmable completion code to better handle newlines in lists
+ of possible completions (e.g., `complete -W').
+
+l. Removed the reserved words from the `bash-builtins' manual page.
+
+m. Parser error reporting now attempts to do a better job of identifying the
+ token in error rather than doing straight textual analysis.
+
+n. Fixes for Inf/NaN, locales, wide/multibyte characters and zero-length
+ arguments in the library snprintf(3) replacement.
+
+o. `read -e' no longer does command name completion on the first word on
+ the line being read.
+
+p. `select' now returns failure if the read of the user's selection fails.
+
+q. Fixed a bug that could cause a core dump when setting $PIPESTATUS.
+
+r. Fixes to not allocate so many job slots when the shell is running a loop
+ with job control enabled in a subshell of an interactive shell.
+
+s. Fixed a bug in the trap code that caused traps to be inherited by
+ command substitutions in some cases.
+
+t. Fixed a bug that could cause alias expansion to inappropriately expand
+ the word following the alias.
+
+u. Fixed a bug in the `kill' builtin that mishandled negative pid arguments.
+
+v. The parser is less lenient when parsing assignment statements where the
+ characters before the `=' don't comprise a valid identifier.
+
+w. The arithmetic expression evaluation code now honors the setting of the
+ `-u' option when expanding variable names.
+
+x. Fixed the arithmetic evaluation code to allow array subscripts to be
+ assigned (`let b[7]=42') and auto-incremented and auto-decremented
+ (e.g., b[7]++).
+
+y. Reimplemented the existing prompt string date and time expansions using
+ strftime(3), which changed the output of \@ in some locales.
+
+z. Fixed a bug that could cause a core dump when a special shell variable
+ (like RANDOM) was converted to an array with a variable assignment.
+
+aa. Fixed a bug that would reset the handler for a signal the user had
+ trapped to a function that would exit the shell when setting the exit
+ trap in a non-interactive shell.
+
+bb. Changed the execve(2) wrapper code to check whether or not a failing
+ command is a directory before looking at whether a `#!' interpreter
+ failed for some reason.
+
+cc. Fixed a bug in the command printing code so it no longer inserts a `;'
+ after a newline, which produces a syntax error when reused as input.
+
+dd. The code that expands $PS4 no longer inherits the `-x' flag.
+
+ee. The bash-specific completion functions may now take advantage of the
+ double-TAB and M-? features of the standard readline completion
+ functions.
+
+ff. The mail checking code no longer prints a message if the checked file's
+ size has not increased, even if the access time is less than the modification time.
+
+gg. Rewrote the variable symbol table code: there is now a stack of
+ contexts, each possibly including a separate symbol table; there can
+ be more than one temporary environment supplied to nested invocations
+ of `./source'; the temporary environments no longer require so much
+ special-case code; shell functions now handle the temporary environment
+ and local variables more consistently; function scope exit is faster now
+ that the entire symbol table does not have to be traversed to dispose of
+ local variables; it is now easier to push vars from the temporary
+ environment to the shell's variable table in posix mode; some duplicated
+ code has been removed.
+
+hh. Regularized the error message printing code; builtin_error is now called
+ more consistently, and common error message strings are handled by small
+ functions. This should make eventual message translation easier.
+
+ii. Error messages now include the line number in a script when the shell
+ is not interactive.
+
+jj. Array subscript expansion now takes place even when the array variable is
+ unset, so side effects will take place.
+
+kk. Fixed a bug in the SICGHLD child-reaping code so that it won't find
+ jobs already marked as terminated if the OS reuses pids quickly enough.
+
+ll. Fixed a bug that could cause a signal to not interrupt the `wait'
+ builtin while it was waiting for a background process to terminate.
+
+mm. A couple of changes to make it easier for multiple shells to share history
+ files using `history -n', `history -r', and `history -w'.
+
+nn. The `getopts' builtin always increments OPTIND to point to the next
+ option to be handled when an option is returned, whether it's valid
+ or not, as POSIX 1003.x-2001 requires.
+
+oo. Changed some parts of the expansion code to avoid allocating and
+ immediately freeing memory without using the results for anything.
+
+pp. The shell now keeps track of $IFS internally, updating its internal map
+ each time the variable is assigned a new value (or at local scope exit).
+ This saves thousands of hash lookups for IFS, which, while individually
+ cheap, add up.
+
+qq. Rewrote the hash table code: searching and insertion are much faster now,
+ and it uses a better string hashing function; augmented the function
+ interface to simplify other parts of the code and remove duplicated code
+
+rr. The shell now uses a simple, generic `object cache' for allocating and
+ caching words and word lists, which were the major users of
+ malloc/free.
+
+ss. Fixed the assignment statement parsing code to allow whitespace and
+ newlines in subscripts when performing array element assignment.
+
+tt. The shell now issues many fewer calls to sigprocmask and other signal
+ masking system calls.
+
+uu. Fixed the `test' and conditional command file comparison operators to
+ work right when one file has a non-positive timestamp and the other
+ does not exist.
+
+vv. Fixed some cases where the special characters '\001' and '\177' in the
+ values of variables or positional parameters caused incorrect expansion
+ results.
+
+2. Changes to Readline
+
+a. Fixed output of comment-begin character when listing variable values.
+
+b. Added some default key bindings for common escape sequences produced by
+ HOME and END keys.
+
+c. Fixed the mark handling code to be more emacs-compatible.
+
+d. A bug was fixed in the code that prints possible completions to keep it
+ from printing empty strings in certain circumstances.
+
+e. Change the key sequence printing code to print ESC as M\- if ESC is a
+ meta-prefix character -- it's easier for users to understand than \e.
+
+f. Fixed unstifle_history() to return values that match the documentation.
+
+g. Fixed the event loop (rl_event_hook) to handle the case where the input
+ file descriptor is invalidated.
+
+h. Fixed the prompt display code to work better when the application has a
+ custom redisplay function.
+
+i. Changes to make reading and writing the history file a little faster, and
+ to cope with huge history files without calling abort(3) from xmalloc.
+
+j. The vi-mode `S' and `s' commands are now undone correctly.
+
+3. New Features in Bash
+
+a. If set, TMOUT is the default timeout for the `read' builtin.
+
+b. `type' has two new options: `-f' suppresses shell function lookup, and
+ `-P' forces a $PATH search.
+
+c. New code to handle multibyte characters.
+
+d. `select' was changed to be more ksh-compatible, in that the menu is
+ reprinted each time through the loop only if REPLY is set to NULL.
+ The previous behavior is available as a compile-time option.
+
+e. `complete -d' and `complete -o dirnames' now force a slash to be
+ appended to names which are symlinks to directories.
+
+f. There is now a bindable edit-and-execute-command readline command,
+ like the vi-mode `v' command, bound to C-xC-e in emacs mode.
+
+g. Added support for ksh93-like [:word:] character class in pattern matching.
+
+h. The $'...' quoting construct now expands \cX to Control-X.
+
+i. A new \D{...} prompt expansion; passes the `...' to strftime and inserts
+ the result into the expanded prompt.
+
+j. The shell now performs arithmetic in the largest integer size the
+ machine supports (intmax_t), instead of long.
+
+k. If a numeric argument is supplied to one of the bash globbing completion
+ functions, a `*' is appended to the word before expansion is attempted.
+
+l. The bash globbing completion functions now allow completions to be listed
+ with double tabs or if `show-all-if-ambiguous' is set.
+
+m. New `-o nospace' option for `complete' and `compgen' builtins; suppresses
+ readline's appending a space to the completed word.
+
+n. 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).
+
+p. There is a new configuration option `--enable-mem-scramble', controls
+ bash malloc behavior of writing garbage characters into memory at
+ allocation and free time.
+
+q. The `complete' and `compgen' builtins now have a new `-s/-A service'
+ option to complete on names from /etc/services.
+
+r. `read' has a new `-u fd' option to read from a specified file descriptor.
+
+s. Fix the completion code so that expansion errors in a directory name
+ don't cause a longjmp back to the command loop.
+
+t. Fixed word completion inside command substitution to work a little more
+ intuitively.
+
+u. The `printf' %q format specifier now uses $'...' quoting to print the
+ argument if it contains non-printing characters.
+
+v. The `declare' and `typeset' builtins have a new `-t' option. When applied
+ to functions, it causes the DEBUG trap to be inherited by the named
+ function. Currently has no effect on variables.
+
+w. The DEBUG trap is now run *before* simple commands, ((...)) commands,
+ [[...]] conditional commands, and for ((...)) loops.
+
+x. 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.
+
+y. 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. Code
+ from Gary Vaughan.
+
+z. New [n]<&word- and [n]>&word- redirections from ksh93 -- move fds (dup
+ and close).
+
+aa. There is a new `-l' invocation option, equivalent to `--login'.
+
+bb. The `hash' builtin has a new `-l' option to list contents in a reusable
+ format, and a `-d' option to remove a name from the hash table.
+
+4. New Features in Readline
+
+a. Support for key `subsequences': allows, e.g., ESC and ESC-a to both
+ be bound to readline functions. Now the arrow keys may be used in vi
+ insert mode.
+
+b. When listing completions, and the number of lines displayed is more than
+ the screen length, readline uses an internal pager to display the results.
+ This is controlled by the `page-completions' variable (default on).
+
+c. New code to handle editing and displaying multibyte characters.
+
+d. The behavior introduced in bash-2.05a of deciding whether or not to
+ append a slash to a completed name that is a symlink to a directory has
+ been made optional, controlled by the `mark-symlinked-directories'
+ variable (default is the 2.05a behavior).
+
+e. The `insert-comment' command now acts as a toggle if given a numeric
+ argument: if the first characters on the line don't specify a
+ comment, insert one; if they do, delete the comment text
+
+f. New application-settable completion variable:
+ rl_completion_mark_symlink_dirs, allows an application's completion
+ function to temporarily override the user's preference for appending
+ slashes to names which are symlinks to directories.
+
+g. New function available to application completion functions:
+ rl_completion_mode, to tell how the completion function was invoked
+ and decide which argument to supply to rl_complete_internal (to list
+ completions, etc.).
+
+h. Readline now has an overwrite mode, toggled by the `overwrite-mode'
+ bindable command, which could be bound to `Insert'.
+
+i. New application-settable completion variable:
+ rl_completion_suppress_append, inhibits appending of
+ rl_completion_append_character to completed words.
+
+j. New key bindings when reading an incremental search string: ^W yanks
+ the currently-matched word out of the current line into the search
+ string; ^Y yanks the rest of the current line into the search string,
+ DEL or ^H deletes characters from the search string.
+
+------------------------------------------------------------------------------
+This document details the changes between this version, bash-2.05a-release,
+and the previous version, bash-2.05a-rc1.
+
+1. Changes to Bash
+
+a. Fixed the `printf' builtin so that the variable name supplied as an
+ argument to a %n conversion must be a valid shell identifier.
+
+b. Improved the random number generator slightly.
+
+c. Changes to configuration to not put -I/usr/include into $CFLAGS, since
+ it messes up some includes.
+
+d. Corrected description of POSIXLY_CORRECT in man page and info manual.
+
+e. Fixed a couple of cases of incorrect function prototypes that sneaked
+ through and caused compilation problems.
+
+f. A few changes to avoid potential core dumps in the programmable completion
+ code.
+
+g. Fixed a configure problem that could cause a non-existent file to show
+ up in LIBOBJS.
+
+h. Fixed a configure problem that could cause siglist.o to not be built when
+ required.
+
+i. Changes to the strtoimax and strtoumax replacement functions to work
+ around buggy compilers.
+
+j. Fixed a problem with the snprintf replacement function that could
+ potentially cause a core dump.
+
+2. Changes to Readline
+
+a. Fixed a locale-specific problem in the vi-mode `goto mark' command.
+
+b. Fixed Makefile to not put -I/usr/include into CFLAGS, since it can cause
+ include file problems.
+
+------------------------------------------------------------------------------
+This document details the changes between this version, bash-2.05a-rc1,
+and the previous version, bash-2.05a-beta1.
+
+1. Changes to Bash
+
+a. Fixed the snprintf replacement to correctly implement the `alternate form'
+ of the %g and %G conversions.
+
+b. Fixed snprintf to correctly handle the optional precision with the %g and
+ %G conversions.
+
+c. Fixed the arithmetic evaluation code to correct the values of `@' and `_'
+ when translating base-64 constants (they were backwards).
+
+d. New library functions for formatting long and long long ints.
+
+e. Fixed a few places where negative array subscripts could have occurred,
+ mostly as the result of systems using signed characters.
+
+f. Fixed a few places that assumed a pid_t was no wider than an int.
+
+g. Fixed the `maildir' mail checking code to work on systems where a
+ `struct stat' doesn't include an `st_blocks' member.
+
+h. Fixed snprintf to make `unsigned long long' conversion formats (%llu)
+ work better.
+
+i. Fixed snprintf to not print a sign when asked to do an unsigned conversion.
+
+j. Made configure changes to avoid compiling empty source files in lib/sh.
+
+k. New replacement functions (if necessary) for strtoull, strtoll, strtoimax,
+ strtoumax.
+
+l. The `printf' builtin now handles the `ll' and `j' length modifiers
+ directly, since they can affect the type and width of the argument
+ passed to printf(3).
+
+m. Renamed a number of the bash-specific autoconf macros in aclocal.m4 to
+ have more sytematic naming, with accompanying changes to configure.in.
+
+n. Fixed snprintf to handle long doubles and the %a/%A conversions by
+ falling back to sprintf, as long as sprintf supports them.
+
+o. Fixed return value from vsnprintf/snprintf to be the number of characters
+ that would have been printed, even if that number exceeds the buffer
+ size passed as an argument.
+
+p. Bash no longer attempts to define its own versions of some ctype macros
+ if they are implemented as functions in libc but not as macros in
+ <ctype.h>.
+
+q. Changed the variable printing code (used by `set', `export', etc.) to
+ not use the $'...' syntax when in posix mode, since that caused
+ interoperability problems with other shells (most notably with autoconf).
+ When not in posix mode, it uses $'...' if the string to be printed
+ contains non-printing characters and regular single quotes otherwise.
+
+r. snprintf now recognizes the %F conversion.
+
+s. Fixed a bug that could cause the wrong status to be returned by a shell
+ function when the shell is compiled without job control and a null
+ command containing a command substutition was executed in the function.
+
+t. When in posix mode, the default value for MAILCHECK is 600.
+
+u. Bash only initializes FUNCNAME, GROUPS, and DIRSTACK as special variables
+ if they're not in the initial environment.
+
+v. If SECONDS appears in the initial environment with a valid integer value,
+ bash uses that as the starting value, as if an assignment had been
+ performed.
+
+w. Bash no longer auto-exports HOME, PATH, SHELL, or TERM, even though it
+ gives them default values if they don't appear in the initial environment.
+
+x. Bash no longer auto-exports HOSTNAME, HOSTTYPE, MACHTYPE, or OSTYPE,
+ even if it assigns them default values.
+
+y. Bash no longer removes the export attribute from SSH_CLIENT or SSH2_CLIENT
+ if they appear in the initial environment.
+
+z. Bash no longer attempts to discover if it's being run by sshd in order to
+ run the startup files. If the SSH_SOURCE_BASHRC is uncommented in
+ config-top.h it will attempt to do so as previously, but that's commented
+ out in the distributed version.
+
+aa. Fixed a typo in the code that tests for LC_NUMERIC.
+
+bb. The POSIXLY_CORRECT shell variable and its effects are now documented.
+
+cc. Some changes to several of the support shell scripts included in the
+ definitions to try to avoid race conditions and attacks.
+
+dd. Several changes to avoid warnings from `gcc -Wall'.
+
+ee. Fixed a problem with the `unset' builtin that could cause incorrect
+ results if asked to unset a variable and an array subscript in the
+ same command.
+
+ff. A few changes to the shell's temporary file creation code to avoid
+ potential file descriptor leaks and to prefer the system's idea of
+ the temporary directory to use.
+
+gg. Fixes to build with the C alloca in lib/malloc/alloca.c if the system
+ requires it but the shell has been configured --without-bash-malloc.
+
+hh. Updated the documentation to note that only interactive shells resend
+ SIGHUP to all jobs before exiting.
+
+ii. Fixes to only pass unquoted tilde words to tilde_expand, rather than
+ rely on tilde_expand or getpwnam(3) to handle the quotes (MacOS 10.x
+ will remove backslashes in any login name passed to getpwnam(3)).
+
+jj. Small change from Paul Eggert to make LINENO right in commands run with
+ `bash -c'.
+
+2. New Features in Bash
+
+a. The `printf' builtin now handles the %a and %A conversions if they're
+ implemented by printf(3).
+
+b. The `printf' builtin now handles the %F conversion (just about like %f).
+
+c. The `printf' builtin now handles the %n conversion like printf(3). The
+ corresponding argument is the name of a shell variable to which the
+ value is assigned.
+
+3. Changes to Readline
+
+a. Fixed a few places where negative array subscripts could have occurred.
+
+b. Fixed the vi-mode code to use a better method to determine the bounds of
+ the array used to hold the marks.
+
+c. Fixed the defines in chardefs.h to work better when chars are signed.
+
+d. Fixed configure.in to use the new names for bash autoconf macros.
+
+e. Readline no longer attempts to define its own versions of some ctype
+ macros if they are implemented as functions in libc but not as macros in
+ <ctype.h>.
+
+f. Fixed a problem where rl_backward could possibly set point to before
+ the beginning of the line.
+
+------------------------------------------------------------------------------
+This document details the changes between this version, bash-2.05a-beta1,
+and the previous version, bash-2.05a-alpha1.
+
+1. Changes to Bash
+
+a. Fixed a bug in the evalution of arithmetic `for' statements when the
+ expanded expression is NULL.
+
+b. Fixed an unassigned variable problem in the redirection printing code.
+
+c. Added more prototypes to extern function declarations in the header
+ files and to static function declarations in C source files.
+
+d. Make sure called functions have a prototype in scope, to get the arguments
+ and return values right instead of casting. Removed extern function
+ declarations from C source files that were already included in header
+ files.
+
+e. Changed some function arguments to use function typedefs in general.h so
+ the prototypes can be checked. The only use of Function and VFunction
+ now is for unwind-protects.
+
+f. More const changes to function arguments and appropriate variables.
+
+g. Changed the mail checking support to handle `maildir'-style mail
+ directories.
+
+h. Augmented the bash malloc to pass in the file and line number information
+ for each malloc, realloc, and free. This should result in better error
+ messages.
+
+i. The `old' gnu malloc is no longer a configuration option.
+
+j. Augmented the bash malloc with optional tracing and registering allocated
+ and freed memory.
+
+k. Prompt string decoding now saves and restores the value of $? when it
+ expands the prompt string, so command substitutions don't change $?.
+
+i. Array indices are now `long', since shell arithmetic is performed as long,
+ and the internal arrayind_t type is used consistently.
+
+j. Some more `unsigned char *' fixes from Paul Eggert.
+
+k. Fixed a bad call to builtin_error that could cause core dumps when making
+ local variables.
+
+l. `return' may no longer be used to terminate a `select' command, for
+ compatibility with ksh.
+
+m. Changed code that reads octal numbers to do a better job of detecting
+ overflows.
+
+n. The time formatting code no longer uses absolute indices into a buffer,
+ because the buffer size changes depending on the size of a `time_t'.
+
+o. `umask' now prints four digits when printing in octal mode, for
+ compatibility with other shells.
+
+p. Lots of changes to the `printf' builtin from Paul Eggert: it handles `L'
+ formats and long doubles better, and internal functions have been
+ simpified where appropriate.
+
+q. Some `time_t' fixes for machines were a time_t is bigger than a long.
+
+r. Replaced some bash-specific autoconf macros with standard equivalents.
+
+s. Improvmed the code that constructs temporary filenames to make the
+ generated names a bit more random.
+
+t. Added code that checks for ascii before calling any of the is* ctype
+ functions.
+
+u. Changed some places where a `char' was used as an array subscript to use
+ `unsigned char', since a `char' can be negative if it's signed by default.
+
+v. Lots of changes to the `ulimit' builtin from Paul Eggert to add support
+ for the new POSIX-200x RLIM_SAVED_CUR and RLIM_SAVED_MAX values and
+ simplify the code.
+
+w. `ulimit' now prints the description of a resource in any error message
+ relating to fetching or setting that resource's limits.
+
+x. The `snprintf' replacement now computes maximum values at compile
+ time rather than using huge constants for things like long long.
+
+y. Interactive shells now ignore `set -n'.
+
+z. Changed the malloc bookkeeping information so that it's now 8 bytes
+ instead of 12 on most 32-bit machines (saving 4 bytes per allocation),
+ restoring 8-byte alignment.
+
+aa. The malloc error reporting code now attempts to print the file and line
+ number of the call that caused the error.
+
+bb. Changed the redirection error reporting code to catch EBADF errors and
+ report the file descriptor number rather than the file being redirected
+ to or from (e.g., things like `exec 4242<x' where 4242 is an out-of-range
+ file descriptor).
+
+cc. `printf', `echo -e', and the $'...' code now process only two hex digits
+ after a `\x' escape sequence for compatibility with other shells, and
+ the documentation was changed to note that the octal and hex escape
+ sequences result in an eight-bit value rather than strict ASCII.
+
+2. Changes to Readline
+
+a. The completion code now attempts to do a better job of preserving the
+ case of the word the user typed if ignoring case in completions.
+
+b. Readline defaults to not echoing the input and lets the terminal
+ initialization code enable echoing if there is a controlling terminal.
+
+c. The key binding code now processes only two hex digits after a `\x'
+ escape sequence, and the documentation was changed to note that the
+ octal and hex escape sequences result in an eight-bit value rather
+ than strict ASCII.
+
+3. New Features in Bash
+
+a. The builtin `ulimit' now takes two new non-numeric arguments: `hard',
+ meaning the current hard limit, and `soft', meaning the current soft
+ limit, in addition to `unlimited'
+
+b. `ulimit' now prints the option letter associated with a particular
+ resource when printing more than one limit.
+
+c. `ulimit' prints `hard' or `soft' when a value is not `unlimited' but is
+ one of RLIM_SAVED_MAX or RLIM_SAVED_CUR, respectively.
+
+4. New Features in Readline
+
+a. New bindable variable `history-preserve-point'. If set, the history
+ code attempts to place the user at the same location on each history
+ line retrived with previous-history or next-history.
+
+------------------------------------------------------------------------------
+This document details the changes between this version, bash-2.05a-alpha1,
+and the previous version, bash-2.05-release.
+
+1. Changes to Bash
+
+a. Better checks in the redirection code for write errors.
+
+b. bashbug now uses $TMPDIR, defaulting to /tmp, and uses mktemp(1) more
+ portably.
+
+c. System-specific configuration changes for: Interix, OpenBSD, FreeBSD,
+ MacOS X.
+
+d. Some more `const' cleanups through the code.
+
+e. Fixed a typo in the /dev/fd redirection code, better checks for valid
+ numeric fds in /dev/fd.
+
+f. Fixed many parts of the shell to handle integer overflow more gracefully
+ and to do more stringent checks for valid numbers.
+
+g. Fixed mksignames to include config.h.
+
+h. Fixed an uninitialized variable problem that could cause the shell to core
+ dump when replacing characters in a string.
+
+i. New mechanism for updating the patch level when official patches are
+ released (patchlevel.h).
+
+j. configure.in changed to no longer require external files _distribution and
+ _patchlevel.
+
+k. Fixed non-interactive shell initialization problem when bash started as
+ `bash -i filename'.
+
+l. Fixed printf builtin conversion error handling to be POSIX.2-conformant.
+
+m. autoconf-2.52 is now used to build configure; autoconf-2.50 or newer is
+ required. Some of the bash-specific macros were removed, since they are
+ now standard.
+
+n. Startup files and files read with source or `.' are no longer required to
+ be regular files.
+
+o. Fixed core dump in builtin printf when user-supplied precision or field
+ width is 0.
+
+p. Fixed builtin printf to treat a negative field width as a positive field
+ width with left-justification.
+
+r. New unwind-protect implementation from Paul Eggert.
+
+s. Fixed an inadvertently-unclosed comment in the bash completion code that
+ caused programmable completions to not add trailing slashes or spaces to
+ completions.
+
+t. Fixed the process substitution code to cope better when stdin is closed.
+
+v. Fixes, mostly from Paul Eggert, for a few possible buffer overflows in
+ the shell.
+
+w. Fixes from Paul Eggert to avoid most of the type casts in the shell code,
+ and use more appropriate types for a number of variables.
+
+x. Command substition no longer inherits the DEBUG trap.
+
+y. Some fixes to the process substition code on machines without /dev/fd so
+ that named pipes are not removed inappropriately.
+
+z. The loadable `getconf' builtin is now much more complete, and will become
+ part of the shell in the future.
+
+aa. The select command no longer terminates on a `return', so it can be used
+ to return from an enclosing function (as ksh does it).
+
+bb. Fixed the extended pattern matching code to behave better when presented
+ with incorrectly-formed patterns.
+
+cc. Some changes were made with the intent of making cross-compilation easier.
+
+dd. The network code (/dev/tcp and /dev/udp redirections) uses getaddrinfo(3)
+ if it's available, which adds support for IPv6.
+
+ee. Subshells of login shells no longer source ~/.bash_logout when they exit.
+
+ff. Fixes so that subshells don't exit inappropriately if the -e option has
+ been set.
+
+gg. Restricted shells no longer allow functions to be exported.
+
+hh. Changes to the pattern matching code so extended pattern matching works
+ on systems with deficient shared library implementations, like MacOS X.
+
+ii. Better error messages when a script with a leading `#!interp' fails
+ to execute because of problems with `interp'.
+
+jj. Fixed `compgen' to handle the `-o default' option better.
+
+kk. Fixed the job control code to force an asynchronous process's standard
+ input to /dev/null only if job control is not active.
+
+ll. Fixed a possible infinite recursion problem when `fc ""=abc' (a null
+ pattern) is used to re-execute a previous command.
+
+mm. Fixed `declare [-a] var=value' to assign VALUE to element 0 if VAR is an
+ array variable. Similarly for `declare [-a] var[N]=value'. This is like
+ ksh93.
+
+nn. Fixed a bug that caused `read -a aname' to work even if ANAME had been
+ declared readonly.
+
+oo. Fixed a possible integer overflow problem when constructing names for
+ temporary files.
+
+2. New Features in Bash
+
+a. Added support for DESTDIR installation root prefix, so you can do a
+ `make install DESTDIR=bash-root' and do easier binary packaging.
+
+b. Added support for builtin printf "'" flag character as per latest POSIX
+ drafts.
+
+c. Support for POSIX.2 printf(1) length specifiers `j', `t', and `z' (from
+ ISO C99).
+
+d. New autoconf macro, RL_LIB_READLINE_VERSION, for use by other applications
+ (bash doesn't use very much of what it returns).
+
+e. `set [-+]o nolog' is recognized as required by the latest POSIX drafts,
+ but ignored.
+
+f. New read-only `shopt' option: login_shell. Set to non-zero value if the
+ shell is a login shell.
+
+g. New `\A' prompt string escape sequence; expands to time in 24 HH:MM format.
+
+h. New `-A group/-g' option to complete and compgen; does group name
+ completion.
+
+i. New `-t' option to `hash' to list hash values for each filename argument.
+
+j. New [-+]O invocation option to set and unset `shopt' options at startup.
+
+k. configure's `--with-installed-readline' option now takes an optional
+ `=PATH' suffix to set the root of the tree where readline is installed
+ to PATH.
+
+l. The ksh-like `ERR' trap has been added. The `ERR' trap will be run
+ whenever the shell would have exited if the -e option were enabled.
+ It is not inherited by shell functions.
+
+m. `readonly', `export', and `declare' now print variables which have been
+ given attributes but not set by assigning a value as just a command and
+ a variable name (like `export foo') when listing, as the latest POSIX
+ drafts require.
+
+n. `bashbug' now requires that the subject be changed from the default.
+
+o. configure has a new `--enable-largefile' option, like other GNU utilities.
+
+p. `for' loops now allow empty word lists after `in', like the latest POSIX
+ drafts require.
+
+3. Changes to Readline
+
+a. More `const' and type casting fixes.
+
+b. Changed rl_message() to use vsnprintf(3) (if available) to fix buffer
+ overflow problems.
+
+c. The completion code no longer appends a `/' or ` ' to a match when
+ completing a symbolic link that resolves to a directory name, unless
+ the match does not add anything to the word being completed. This
+ means that a tab will complete the word up to the full name, but not
+ add anything, and a subsequent tab will add a slash.
+
+d. Fixed a trivial typo that made the vi-mode `dT' command not work.
+
+e. Fixed the tty code so that ^S and ^Q can be inserted with rl_quoted_insert.
+
+f. Fixed the tty code so that ^V works more than once.
+
+g. Changed the use of __P((...)) for function prototypes to PARAMS((...))
+ because the use of __P in typedefs conflicted g++ and glibc.
+
+4. New Features in Readline
+
+a. Added extern declaration for rl_get_termcap to readline.h, making it a
+ public function (it was always there, just not in readline.h).
+
+b. New #defines in readline.h: RL_READLINE_VERSION, currently 0x0402,
+ RL_VERSION_MAJOR, currently 4, and RL_VERSION_MINOR, currently 2.
+
+c. New readline variable: rl_readline_version, mirrors RL_READLINE_VERSION.
+
+d. New bindable boolean readline variable: match-hidden-files. Controls
+ completion of files beginning with a `.' (on Unix). Enabled by default.
+
+e. The history expansion code now allows any character to terminate a
+ `:first-' modifier, like csh.
+
+f. The incremental search code remembers the last search string and uses
+ it if ^R^R is typed without a search string.
+
+------------------------------------------------------------------------------
This document details the changes between this version, bash-2.05-release,
and the previous version, bash-2.05-beta2.
projects / thirdparty / bash.git / blobdiff