f\bfa\bal\bls\bse\be Does nothing; returns a non-zero status.
- f\bfc\bc [-\b-e\be _\be_\bn_\ba_\bm_\be] [-\b-l\bln\bnr\br] [_\bf_\bi_\br_\bs_\bt] [_\bl_\ba_\bs_\bt]
+ f\bfc\bc [-\b-e\be _\be_\bn_\ba_\bm_\be] [-\b-D\bD] [-\b-l\bln\bnr\br] [_\bf_\bi_\br_\bs_\bt] [_\bl_\ba_\bs_\bt]
f\bfc\bc -\b-s\bs [_\bp_\ba_\bt=_\br_\be_\bp] [_\bc_\bm_\bd]
The first form selects a range of commands from _\bf_\bi_\br_\bs_\bt to _\bl_\ba_\bs_\bt
from the history list and displays or edits and re-executes
value of the F\bFC\bCE\bED\bDI\bIT\bT variable, and the value of E\bED\bDI\bIT\bTO\bOR\bR if F\bFC\bCE\bED\bDI\bIT\bT
is not set. If neither variable is set, f\bfc\bc uses _\bv_\bi_\b. When edit-
ing is complete, f\bfc\bc reads the file containing the edited com-
- mands and echoes and executes them.
+ mands and echoes and executes them. The -\b-D\bD option, if supplied,
+ causes f\bfc\bc to remove the selected commands from the history list
+ before executing the file of edited commands. -\b-D\bD is only active
+ when f\bfc\bc is invoked in this way.
- In the second form, f\bfc\bc re-executes _\bc_\bo_\bm_\bm_\ba_\bn_\bd after replacing each
- instance of _\bp_\ba_\bt with _\br_\be_\bp. _\bC_\bo_\bm_\bm_\ba_\bn_\bd is interpreted the same as
+ In the second form, f\bfc\bc re-executes _\bc_\bo_\bm_\bm_\ba_\bn_\bd after replacing each
+ instance of _\bp_\ba_\bt with _\br_\be_\bp. _\bC_\bo_\bm_\bm_\ba_\bn_\bd is interpreted the same as
_\bf_\bi_\br_\bs_\bt above.
- A useful alias to use with f\bfc\bc is "r="fc -s"", so that typing "r
+ A useful alias to use with f\bfc\bc is "r="fc -s"", so that typing "r
cc" runs the last command beginning with "cc" and typing "r" re-
executes the last command.
- If the first form is used, the return value is zero unless an
- invalid option is encountered or _\bf_\bi_\br_\bs_\bt or _\bl_\ba_\bs_\bt specify history
- lines out of range. When editing and re-executing a file of
+ If the first form is used, the return value is zero unless an
+ invalid option is encountered or _\bf_\bi_\br_\bs_\bt or _\bl_\ba_\bs_\bt specify history
+ lines out of range. When editing and re-executing a file of
commands, the return value is the value of the last command exe-
cuted or failure if an error occurs with the temporary file. If
the second form is used, the return status is that of the re-ex-
- ecuted command, unless _\bc_\bm_\bd does not specify a valid history en-
+ ecuted command, unless _\bc_\bm_\bd does not specify a valid history en-
try, in which case f\bfc\bc returns a non-zero status.
f\bfg\bg [_\bj_\bo_\bb_\bs_\bp_\be_\bc]
- Resume _\bj_\bo_\bb_\bs_\bp_\be_\bc in the foreground, and make it the current job.
- If _\bj_\bo_\bb_\bs_\bp_\be_\bc is not present, f\bfg\bg uses the shell's notion of the
- _\bc_\bu_\br_\br_\be_\bn_\bt _\bj_\bo_\bb. The return value is that of the command placed
- into the foreground, or failure if run when job control is dis-
+ Resume _\bj_\bo_\bb_\bs_\bp_\be_\bc in the foreground, and make it the current job.
+ If _\bj_\bo_\bb_\bs_\bp_\be_\bc is not present, f\bfg\bg uses the shell's notion of the
+ _\bc_\bu_\br_\br_\be_\bn_\bt _\bj_\bo_\bb. The return value is that of the command placed
+ into the foreground, or failure if run when job control is dis-
abled or, when run with job control enabled, if _\bj_\bo_\bb_\bs_\bp_\be_\bc does not
- specify a valid job or _\bj_\bo_\bb_\bs_\bp_\be_\bc specifies a job that was started
+ specify a valid job or _\bj_\bo_\bb_\bs_\bp_\be_\bc specifies a job that was started
without job control.
g\bge\bet\bto\bop\bpt\bts\bs _\bo_\bp_\bt_\bs_\bt_\br_\bi_\bn_\bg _\bn_\ba_\bm_\be [_\ba_\br_\bg ...]
- g\bge\bet\bto\bop\bpt\bts\bs is used by shell scripts and functions to parse posi-
- tional parameters and obtain options and their arguments. _\bo_\bp_\bt_\b-
- _\bs_\bt_\br_\bi_\bn_\bg contains the option characters to be recognized; if a
+ g\bge\bet\bto\bop\bpt\bts\bs is used by shell scripts and functions to parse posi-
+ tional parameters and obtain options and their arguments. _\bo_\bp_\bt_\b-
+ _\bs_\bt_\br_\bi_\bn_\bg contains the option characters to be recognized; if a
character is followed by a colon, the option is expected to have
- an argument, which should be separated from it by white space.
+ an argument, which should be separated from it by white space.
The colon and question mark characters may not be used as option
characters.
- Each time it is invoked, g\bge\bet\bto\bop\bpt\bts\bs places the next option in the
+ Each time it is invoked, g\bge\bet\bto\bop\bpt\bts\bs places the next option in the
shell variable _\bn_\ba_\bm_\be, initializing _\bn_\ba_\bm_\be if it does not exist, and
the index of the next argument to be processed into the variable
- O\bOP\bPT\bTI\bIN\bND\bD. O\bOP\bPT\bTI\bIN\bND\bD is initialized to 1 each time the shell or a
- shell script is invoked. When an option requires an argument,
+ O\bOP\bPT\bTI\bIN\bND\bD. O\bOP\bPT\bTI\bIN\bND\bD is initialized to 1 each time the shell or a
+ shell script is invoked. When an option requires an argument,
g\bge\bet\bto\bop\bpt\bts\bs places that argument into the variable O\bOP\bPT\bTA\bAR\bRG\bG.
- The shell does not reset O\bOP\bPT\bTI\bIN\bND\bD automatically; it must be manu-
- ally reset between multiple calls to g\bge\bet\bto\bop\bpt\bts\bs within the same
+ The shell does not reset O\bOP\bPT\bTI\bIN\bND\bD automatically; it must be manu-
+ ally reset between multiple calls to g\bge\bet\bto\bop\bpt\bts\bs within the same
shell invocation to use a new set of parameters.
- When it reaches the end of options, g\bge\bet\bto\bop\bpt\bts\bs exits with a return
- value greater than zero. O\bOP\bPT\bTI\bIN\bND\bD is set to the index of the
+ When it reaches the end of options, g\bge\bet\bto\bop\bpt\bts\bs exits with a return
+ value greater than zero. O\bOP\bPT\bTI\bIN\bND\bD is set to the index of the
first non-option argument, and _\bn_\ba_\bm_\be is set to ?.
- g\bge\bet\bto\bop\bpt\bts\bs normally parses the positional parameters, but if more
- arguments are supplied as _\ba_\br_\bg values, g\bge\bet\bto\bop\bpt\bts\bs parses those in-
+ g\bge\bet\bto\bop\bpt\bts\bs normally parses the positional parameters, but if more
+ arguments are supplied as _\ba_\br_\bg values, g\bge\bet\bto\bop\bpt\bts\bs parses those in-
stead.
- g\bge\bet\bto\bop\bpt\bts\bs can report errors in two ways. If the first character
- of _\bo_\bp_\bt_\bs_\bt_\br_\bi_\bn_\bg is a colon, g\bge\bet\bto\bop\bpt\bts\bs uses _\bs_\bi_\bl_\be_\bn_\bt error reporting.
- In normal operation, g\bge\bet\bto\bop\bpt\bts\bs prints diagnostic messages when it
- encounters invalid options or missing option arguments. If the
- variable O\bOP\bPT\bTE\bER\bRR\bR is set to 0, g\bge\bet\bto\bop\bpt\bts\bs does not display any error
- messages, even if the first character of _\bo_\bp_\bt_\bs_\bt_\br_\bi_\bn_\bg is not a
+ g\bge\bet\bto\bop\bpt\bts\bs can report errors in two ways. If the first character
+ of _\bo_\bp_\bt_\bs_\bt_\br_\bi_\bn_\bg is a colon, g\bge\bet\bto\bop\bpt\bts\bs uses _\bs_\bi_\bl_\be_\bn_\bt error reporting.
+ In normal operation, g\bge\bet\bto\bop\bpt\bts\bs prints diagnostic messages when it
+ encounters invalid options or missing option arguments. If the
+ variable O\bOP\bPT\bTE\bER\bRR\bR is set to 0, g\bge\bet\bto\bop\bpt\bts\bs does not display any error
+ messages, even if the first character of _\bo_\bp_\bt_\bs_\bt_\br_\bi_\bn_\bg is not a
colon.
If g\bge\bet\bto\bop\bpt\bts\bs detects an invalid option, it places ? into _\bn_\ba_\bm_\be and,
- if not silent, prints an error message and unsets O\bOP\bPT\bTA\bAR\bRG\bG. If
- g\bge\bet\bto\bop\bpt\bts\bs is silent, it assigns the option character found to O\bOP\bP-\b-
+ if not silent, prints an error message and unsets O\bOP\bPT\bTA\bAR\bRG\bG. If
+ g\bge\bet\bto\bop\bpt\bts\bs is silent, it assigns the option character found to O\bOP\bP-\b-
T\bTA\bAR\bRG\bG and does not print a diagnostic message.
- If a required argument is not found, and g\bge\bet\bto\bop\bpt\bts\bs is not silent,
+ If a required argument is not found, and g\bge\bet\bto\bop\bpt\bts\bs is not silent,
it sets the value of _\bn_\ba_\bm_\be to a question mark (?\b?), unsets O\bOP\bPT\bTA\bAR\bRG\bG,
- and prints a diagnostic message. If g\bge\bet\bto\bop\bpt\bts\bs is silent, it sets
- the value of _\bn_\ba_\bm_\be to a colon (:\b:) and sets O\bOP\bPT\bTA\bAR\bRG\bG to the option
+ and prints a diagnostic message. If g\bge\bet\bto\bop\bpt\bts\bs is silent, it sets
+ the value of _\bn_\ba_\bm_\be to a colon (:\b:) and sets O\bOP\bPT\bTA\bAR\bRG\bG to the option
character found.
- g\bge\bet\bto\bop\bpt\bts\bs returns true if an option, specified or unspecified, is
+ g\bge\bet\bto\bop\bpt\bts\bs returns true if an option, specified or unspecified, is
found. It returns false if the end of options is encountered or
an error occurs.
h\bha\bas\bsh\bh [-\b-l\blr\br] [-\b-p\bp _\bf_\bi_\bl_\be_\bn_\ba_\bm_\be] [-\b-d\bdt\bt] [_\bn_\ba_\bm_\be]
Each time h\bha\bas\bsh\bh is invoked, it remembers the full pathname of the
- command _\bn_\ba_\bm_\be as determined by searching the directories in
- $\b$P\bPA\bAT\bTH\bH. Any previously-remembered pathname associated with _\bn_\ba_\bm_\be
- is discarded. If the -\b-p\bp option is supplied, h\bha\bas\bsh\bh uses _\bf_\bi_\bl_\be_\bn_\ba_\bm_\be
+ command _\bn_\ba_\bm_\be as determined by searching the directories in
+ $\b$P\bPA\bAT\bTH\bH. Any previously-remembered pathname associated with _\bn_\ba_\bm_\be
+ is discarded. If the -\b-p\bp option is supplied, h\bha\bas\bsh\bh uses _\bf_\bi_\bl_\be_\bn_\ba_\bm_\be
as the full pathname of the command.
- The -\b-r\br option causes the shell to forget all remembered loca-
- tions. Assigning to the P\bPA\bAT\bTH\bH variable also clears all hashed
- filenames. The -\b-d\bd option causes the shell to forget the remem-
+ The -\b-r\br option causes the shell to forget all remembered loca-
+ tions. Assigning to the P\bPA\bAT\bTH\bH variable also clears all hashed
+ filenames. The -\b-d\bd option causes the shell to forget the remem-
bered location of each _\bn_\ba_\bm_\be.
If the -\b-t\bt option is supplied, h\bha\bas\bsh\bh prints the full pathname cor-
- responding to each _\bn_\ba_\bm_\be. If multiple _\bn_\ba_\bm_\be arguments are sup-
- plied with -\b-t\bt, h\bha\bas\bsh\bh prints the _\bn_\ba_\bm_\be before the corresponding
+ responding to each _\bn_\ba_\bm_\be. If multiple _\bn_\ba_\bm_\be arguments are sup-
+ plied with -\b-t\bt, h\bha\bas\bsh\bh prints the _\bn_\ba_\bm_\be before the corresponding
hashed full pathname. The -\b-l\bl option displays output in a format
that may be reused as input.
- If no arguments are given, or if only -\b-l\bl is supplied, h\bha\bas\bsh\bh
- prints information about remembered commands. The -\b-t\bt, -\b-d\bd, and
- -\b-p\bp options (the options that act on the _\bn_\ba_\bm_\be arguments) are mu-
+ If no arguments are given, or if only -\b-l\bl is supplied, h\bha\bas\bsh\bh
+ prints information about remembered commands. The -\b-t\bt, -\b-d\bd, and
+ -\b-p\bp options (the options that act on the _\bn_\ba_\bm_\be arguments) are mu-
tually exclusive. Only one will be active. If more than one is
- supplied, -\b-t\bt has higher priority than -\b-p\bp, and both have higher
+ supplied, -\b-t\bt has higher priority than -\b-p\bp, and both have higher
priority than -\b-d\bd.
- The return status is zero unless a _\bn_\ba_\bm_\be is not found or an in-
+ The return status is zero unless a _\bn_\ba_\bm_\be is not found or an in-
valid option is supplied.
h\bhe\bel\blp\bp [-\b-d\bdm\bms\bs] [_\bp_\ba_\bt_\bt_\be_\br_\bn]
- Display helpful information about builtin commands. If _\bp_\ba_\bt_\bt_\be_\br_\bn
- is specified, h\bhe\bel\blp\bp gives detailed help on all commands matching
- _\bp_\ba_\bt_\bt_\be_\br_\bn as described below; otherwise it displays a list of all
+ Display helpful information about builtin commands. If _\bp_\ba_\bt_\bt_\be_\br_\bn
+ is specified, h\bhe\bel\blp\bp gives detailed help on all commands matching
+ _\bp_\ba_\bt_\bt_\be_\br_\bn as described below; otherwise it displays a list of all
the builtins and shell compound commands.
Options, if supplied, have the follow meanings:
format
-\b-s\bs Display only a short usage synopsis for each _\bp_\ba_\bt_\bt_\be_\br_\bn
- If _\bp_\ba_\bt_\bt_\be_\br_\bn contains pattern matching characters (see P\bPa\bat\btt\bte\ber\brn\bn
- M\bMa\bat\btc\bch\bhi\bin\bng\bg above) it's treated as a shell pattern and h\bhe\bel\blp\bp prints
+ If _\bp_\ba_\bt_\bt_\be_\br_\bn contains pattern matching characters (see P\bPa\bat\btt\bte\ber\brn\bn
+ M\bMa\bat\btc\bch\bhi\bin\bng\bg above) it's treated as a shell pattern and h\bhe\bel\blp\bp prints
the description of each help topic matching _\bp_\ba_\bt_\bt_\be_\br_\bn.
- If not, and _\bp_\ba_\bt_\bt_\be_\br_\bn exactly matches the name of a help topic,
- h\bhe\bel\blp\bp prints the description associated with that topic. Other-
- wise, h\bhe\bel\blp\bp performs prefix matching and prints the descriptions
+ If not, and _\bp_\ba_\bt_\bt_\be_\br_\bn exactly matches the name of a help topic,
+ h\bhe\bel\blp\bp prints the description associated with that topic. Other-
+ wise, h\bhe\bel\blp\bp performs prefix matching and prints the descriptions
of all matching help topics.
The return status is 0 unless no command matches _\bp_\ba_\bt_\bt_\be_\br_\bn.
h\bhi\bis\bst\bto\bor\bry\by -\b-a\ban\bnr\brw\bw [_\bf_\bi_\bl_\be_\bn_\ba_\bm_\be]
h\bhi\bis\bst\bto\bor\bry\by -\b-p\bp _\ba_\br_\bg [_\ba_\br_\bg ...]
h\bhi\bis\bst\bto\bor\bry\by -\b-s\bs _\ba_\br_\bg [_\ba_\br_\bg ...]
- With no options, display the command history list with numbers.
- Entries prefixed with a *\b* have been modified. An argument of _\bn
- lists only the last _\bn entries. If the shell variable H\bHI\bIS\bST\bTT\bTI\bIM\bME\bE-\b-
- F\bFO\bOR\bRM\bMA\bAT\bT is set and not null, it is used as a format string for
- _\bs_\bt_\br_\bf_\bt_\bi_\bm_\be(3) to display the time stamp associated with each dis-
- played history entry. If h\bhi\bis\bst\bto\bor\bry\by uses H\bHI\bIS\bST\bTT\bTI\bIM\bME\bEF\bFO\bOR\bRM\bMA\bAT\bT, it does
- not print an intervening space between the formatted time stamp
+ With no options, display the command history list with numbers.
+ Entries prefixed with a *\b* have been modified. An argument of _\bn
+ lists only the last _\bn entries. If the shell variable H\bHI\bIS\bST\bTT\bTI\bIM\bME\bE-\b-
+ F\bFO\bOR\bRM\bMA\bAT\bT is set and not null, it is used as a format string for
+ _\bs_\bt_\br_\bf_\bt_\bi_\bm_\be(3) to display the time stamp associated with each dis-
+ played history entry. If h\bhi\bis\bst\bto\bor\bry\by uses H\bHI\bIS\bST\bTT\bTI\bIM\bME\bEF\bFO\bOR\bRM\bMA\bAT\bT, it does
+ not print an intervening space between the formatted time stamp
and the history entry.
If _\bf_\bi_\bl_\be_\bn_\ba_\bm_\be is supplied, h\bhi\bis\bst\bto\bor\bry\by uses it as the name of the his-
- tory file; if not, it uses the value of H\bHI\bIS\bST\bTF\bFI\bIL\bLE\bE. If _\bf_\bi_\bl_\be_\bn_\ba_\bm_\be
- is not supplied and H\bHI\bIS\bST\bTF\bFI\bIL\bLE\bE is unset or null, the -\b-a\ba,\b, -\b-n\bn,\b, -\b-r\br,\b,
+ tory file; if not, it uses the value of H\bHI\bIS\bST\bTF\bFI\bIL\bLE\bE. If _\bf_\bi_\bl_\be_\bn_\ba_\bm_\be
+ is not supplied and H\bHI\bIS\bST\bTF\bFI\bIL\bLE\bE is unset or null, the -\b-a\ba,\b, -\b-n\bn,\b, -\b-r\br,\b,
and -\b-w\bw options have no effect.
Options, if supplied, have the following meanings:
can be used with the other options to replace the history
list.
-\b-d\bd _\bo_\bf_\bf_\bs_\be_\bt
- Delete the history entry at position _\bo_\bf_\bf_\bs_\be_\bt. If _\bo_\bf_\bf_\bs_\be_\bt
+ Delete the history entry at position _\bo_\bf_\bf_\bs_\be_\bt. If _\bo_\bf_\bf_\bs_\be_\bt
is negative, it is interpreted as relative to one greater
than the last history position, so negative indices count
- back from the end of the history, and an index of -1
+ back from the end of the history, and an index of -1
refers to the current h\bhi\bis\bst\bto\bor\bry\by -\b-d\bd command.
-\b-d\bd _\bs_\bt_\ba_\br_\bt-_\be_\bn_\bd
- Delete the range of history entries between positions
- _\bs_\bt_\ba_\br_\bt and _\be_\bn_\bd, inclusive. Positive and negative values
+ Delete the range of history entries between positions
+ _\bs_\bt_\ba_\br_\bt and _\be_\bn_\bd, inclusive. Positive and negative values
for _\bs_\bt_\ba_\br_\bt and _\be_\bn_\bd are interpreted as described above.
- -\b-a\ba Append the "new" history lines to the history file.
- These are history lines entered since the beginning of
+ -\b-a\ba Append the "new" history lines to the history file.
+ These are history lines entered since the beginning of
the current b\bba\bas\bsh\bh session, but not already appended to the
history file.
- -\b-n\bn Read the history lines not already read from the history
+ -\b-n\bn Read the history lines not already read from the history
file and add them to the current history list. These are
lines appended to the history file since the beginning of
the current b\bba\bas\bsh\bh session.
rent history list.
-\b-w\bw Write the current history list to the history file, over-
writing the history file.
- -\b-p\bp Perform history substitution on the following _\ba_\br_\bg_\bs and
- display the result on the standard output, without stor-
- ing the results in the history list. Each _\ba_\br_\bg must be
+ -\b-p\bp Perform history substitution on the following _\ba_\br_\bg_\bs and
+ display the result on the standard output, without stor-
+ ing the results in the history list. Each _\ba_\br_\bg must be
quoted to disable normal history expansion.
- -\b-s\bs Store the _\ba_\br_\bg_\bs in the history list as a single entry.
- The last command in the history list is removed before
+ -\b-s\bs Store the _\ba_\br_\bg_\bs in the history list as a single entry.
+ The last command in the history list is removed before
adding the _\ba_\br_\bg_\bs.
- If the H\bHI\bIS\bST\bTT\bTI\bIM\bME\bEF\bFO\bOR\bRM\bMA\bAT\bT variable is set, h\bhi\bis\bst\bto\bor\bry\by writes the time
+ If the H\bHI\bIS\bST\bTT\bTI\bIM\bME\bEF\bFO\bOR\bRM\bMA\bAT\bT variable is set, h\bhi\bis\bst\bto\bor\bry\by writes the time
stamp information associated with each history entry to the his-
- tory file, marked with the history comment character as de-
- scribed above. When the history file is read, lines beginning
- with the history comment character followed immediately by a
- digit are interpreted as timestamps for the following history
+ tory file, marked with the history comment character as de-
+ scribed above. When the history file is read, lines beginning
+ with the history comment character followed immediately by a
+ digit are interpreted as timestamps for the following history
entry.
- The return value is 0 unless an invalid option is encountered,
- an error occurs while reading or writing the history file, an
+ The return value is 0 unless an invalid option is encountered,
+ an error occurs while reading or writing the history file, an
invalid _\bo_\bf_\bf_\bs_\be_\bt or range is supplied as an argument to -\b-d\bd, or the
history expansion supplied as an argument to -\b-p\bp fails.
The first form lists the active jobs. The options have the fol-
lowing meanings:
-\b-l\bl List process IDs in addition to the normal information.
- -\b-n\bn Display information only about jobs that have changed
+ -\b-n\bn Display information only about jobs that have changed
status since the user was last notified of their status.
- -\b-p\bp List only the process ID of the job's process group
+ -\b-p\bp List only the process ID of the job's process group
leader.
-\b-r\br Display only running jobs.
-\b-s\bs Display only stopped jobs.
- If _\bj_\bo_\bb_\bs_\bp_\be_\bc is supplied, j\bjo\bob\bbs\bs restricts output to information
+ If _\bj_\bo_\bb_\bs_\bp_\be_\bc is supplied, j\bjo\bob\bbs\bs restricts output to information
about that job. The return status is 0 unless an invalid option
is encountered or an invalid _\bj_\bo_\bb_\bs_\bp_\be_\bc is supplied.
k\bki\bil\bll\bl [-\b-s\bs _\bs_\bi_\bg_\bs_\bp_\be_\bc | -\b-n\bn _\bs_\bi_\bg_\bn_\bu_\bm | -\b-_\bs_\bi_\bg_\bs_\bp_\be_\bc] _\bi_\bd [ ... ]
k\bki\bil\bll\bl -\b-l\bl|-\b-L\bL [_\bs_\bi_\bg_\bs_\bp_\be_\bc | _\be_\bx_\bi_\bt_\b__\bs_\bt_\ba_\bt_\bu_\bs]
- Send the signal specified by _\bs_\bi_\bg_\bs_\bp_\be_\bc or _\bs_\bi_\bg_\bn_\bu_\bm to the processes
+ Send the signal specified by _\bs_\bi_\bg_\bs_\bp_\be_\bc or _\bs_\bi_\bg_\bn_\bu_\bm to the processes
named by each _\bi_\bd. Each _\bi_\bd may be a job specification _\bj_\bo_\bb_\bs_\bp_\be_\bc or
- a process ID _\bp_\bi_\bd. _\bs_\bi_\bg_\bs_\bp_\be_\bc is either a case-insensitive signal
- name such as S\bSI\bIG\bGK\bKI\bIL\bLL\bL (with or without the S\bSI\bIG\bG prefix) or a sig-
- nal number; _\bs_\bi_\bg_\bn_\bu_\bm is a signal number. If _\bs_\bi_\bg_\bs_\bp_\be_\bc is not sup-
+ a process ID _\bp_\bi_\bd. _\bs_\bi_\bg_\bs_\bp_\be_\bc is either a case-insensitive signal
+ name such as S\bSI\bIG\bGK\bKI\bIL\bLL\bL (with or without the S\bSI\bIG\bG prefix) or a sig-
+ nal number; _\bs_\bi_\bg_\bn_\bu_\bm is a signal number. If _\bs_\bi_\bg_\bs_\bp_\be_\bc is not sup-
plied, then k\bki\bil\bll\bl sends S\bSI\bIG\bGT\bTE\bER\bRM\bM.
The -\b-l\bl option lists the signal names. If any arguments are sup-
plied when -\b-l\bl is given, k\bki\bil\bll\bl lists the names of the signals cor-
- responding to the arguments, and the return status is 0. The
- _\be_\bx_\bi_\bt_\b__\bs_\bt_\ba_\bt_\bu_\bs argument to -\b-l\bl is a number specifying either a sig-
- nal number or the exit status of a process terminated by a sig-
- nal; if it is supplied, k\bki\bil\bll\bl prints the name of the signal that
+ responding to the arguments, and the return status is 0. The
+ _\be_\bx_\bi_\bt_\b__\bs_\bt_\ba_\bt_\bu_\bs argument to -\b-l\bl is a number specifying either a sig-
+ nal number or the exit status of a process terminated by a sig-
+ nal; if it is supplied, k\bki\bil\bll\bl prints the name of the signal that
caused the process to terminate. k\bki\bil\bll\bl assumes that process exit
statuses are greater than 128; anything less than that is a sig-
nal number. The -\b-L\bL option is equivalent to -\b-l\bl.
- k\bki\bil\bll\bl returns true if at least one signal was successfully sent,
+ k\bki\bil\bll\bl returns true if at least one signal was successfully sent,
or false if an error occurs or an invalid option is encountered.
l\ble\bet\bt _\ba_\br_\bg [_\ba_\br_\bg ...]
- Each _\ba_\br_\bg is evaluated as an arithmetic expression (see A\bAR\bRI\bIT\bTH\bH-\b-
- M\bME\bET\bTI\bIC\bC E\bEV\bVA\bAL\bLU\bUA\bAT\bTI\bIO\bON\bN above). If the last _\ba_\br_\bg evaluates to 0, l\ble\bet\bt
+ Each _\ba_\br_\bg is evaluated as an arithmetic expression (see A\bAR\bRI\bIT\bTH\bH-\b-
+ M\bME\bET\bTI\bIC\bC E\bEV\bVA\bAL\bLU\bUA\bAT\bTI\bIO\bON\bN above). If the last _\ba_\br_\bg evaluates to 0, l\ble\bet\bt
returns 1; otherwise l\ble\bet\bt returns 0.
l\blo\boc\bca\bal\bl [_\bo_\bp_\bt_\bi_\bo_\bn] [_\bn_\ba_\bm_\be[=_\bv_\ba_\bl_\bu_\be] ... | - ]
For each argument, create a local variable named _\bn_\ba_\bm_\be and assign
- it _\bv_\ba_\bl_\bu_\be. The _\bo_\bp_\bt_\bi_\bo_\bn can be any of the options accepted by d\bde\be-\b-
- c\bcl\bla\bar\bre\be. When l\blo\boc\bca\bal\bl is used within a function, it causes the
- variable _\bn_\ba_\bm_\be to have a visible scope restricted to that func-
- tion and its children. It is an error to use l\blo\boc\bca\bal\bl when not
+ it _\bv_\ba_\bl_\bu_\be. The _\bo_\bp_\bt_\bi_\bo_\bn can be any of the options accepted by d\bde\be-\b-
+ c\bcl\bla\bar\bre\be. When l\blo\boc\bca\bal\bl is used within a function, it causes the
+ variable _\bn_\ba_\bm_\be to have a visible scope restricted to that func-
+ tion and its children. It is an error to use l\blo\boc\bca\bal\bl when not
within a function.
- If _\bn_\ba_\bm_\be is -, it makes the set of shell options local to the
- function in which l\blo\boc\bca\bal\bl is invoked: any shell options changed
- using the s\bse\bet\bt builtin inside the function after the call to l\blo\bo-\b-
- c\bca\bal\bl are restored to their original values when the function re-
- turns. The restore is performed as if a series of s\bse\bet\bt commands
- were executed to restore the values that were in place before
+ If _\bn_\ba_\bm_\be is -, it makes the set of shell options local to the
+ function in which l\blo\boc\bca\bal\bl is invoked: any shell options changed
+ using the s\bse\bet\bt builtin inside the function after the call to l\blo\bo-\b-
+ c\bca\bal\bl are restored to their original values when the function re-
+ turns. The restore is performed as if a series of s\bse\bet\bt commands
+ were executed to restore the values that were in place before
the function.
- With no operands, l\blo\boc\bca\bal\bl writes a list of local variables to the
+ With no operands, l\blo\boc\bca\bal\bl writes a list of local variables to the
standard output.
- The return status is 0 unless l\blo\boc\bca\bal\bl is used outside a function,
+ The return status is 0 unless l\blo\boc\bca\bal\bl is used outside a function,
an invalid _\bn_\ba_\bm_\be is supplied, or _\bn_\ba_\bm_\be is a readonly variable.
l\blo\bog\bgo\bou\but\bt [\b[_\bn]\b]
- Exit a login shell, returning a status of _\bn to the shell's par-
+ Exit a login shell, returning a status of _\bn to the shell's par-
ent.
m\bma\bap\bpf\bfi\bil\ble\be [-\b-d\bd _\bd_\be_\bl_\bi_\bm] [-\b-n\bn _\bc_\bo_\bu_\bn_\bt] [-\b-O\bO _\bo_\br_\bi_\bg_\bi_\bn] [-\b-s\bs _\bc_\bo_\bu_\bn_\bt] [-\b-t\bt] [-\b-u\bu _\bf_\bd] [-\b-C\bC
_\bc_\ba_\bl_\bl_\bb_\ba_\bc_\bk] [-\b-c\bc _\bq_\bu_\ba_\bn_\bt_\bu_\bm] [_\ba_\br_\br_\ba_\by]
r\bre\bea\bad\bda\bar\brr\bra\bay\by [-\b-d\bd _\bd_\be_\bl_\bi_\bm] [-\b-n\bn _\bc_\bo_\bu_\bn_\bt] [-\b-O\bO _\bo_\br_\bi_\bg_\bi_\bn] [-\b-s\bs _\bc_\bo_\bu_\bn_\bt] [-\b-t\bt] [-\b-u\bu _\bf_\bd] [-\b-C\bC
_\bc_\ba_\bl_\bl_\bb_\ba_\bc_\bk] [-\b-c\bc _\bq_\bu_\ba_\bn_\bt_\bu_\bm] [_\ba_\br_\br_\ba_\by]
- Read lines from the standard input, or from file descriptor _\bf_\bd
- if the -\b-u\bu option is supplied, into the indexed array variable
- _\ba_\br_\br_\ba_\by. The variable M\bMA\bAP\bPF\bFI\bIL\bLE\bE is the default _\ba_\br_\br_\ba_\by. Options, if
+ Read lines from the standard input, or from file descriptor _\bf_\bd
+ if the -\b-u\bu option is supplied, into the indexed array variable
+ _\ba_\br_\br_\ba_\by. The variable M\bMA\bAP\bPF\bFI\bIL\bLE\bE is the default _\ba_\br_\br_\ba_\by. Options, if
supplied, have the following meanings:
- -\b-d\bd Use the first character of _\bd_\be_\bl_\bi_\bm to terminate each input
+ -\b-d\bd Use the first character of _\bd_\be_\bl_\bi_\bm to terminate each input
line, rather than newline. If _\bd_\be_\bl_\bi_\bm is the empty string,
m\bma\bap\bpf\bfi\bil\ble\be will terminate a line when it reads a NUL charac-
ter.
-\b-n\bn Copy at most _\bc_\bo_\bu_\bn_\bt lines. If _\bc_\bo_\bu_\bn_\bt is 0, copy all lines.
- -\b-O\bO Begin assigning to _\ba_\br_\br_\ba_\by at index _\bo_\br_\bi_\bg_\bi_\bn. The default
+ -\b-O\bO Begin assigning to _\ba_\br_\br_\ba_\by at index _\bo_\br_\bi_\bg_\bi_\bn. The default
index is 0.
-\b-s\bs Discard the first _\bc_\bo_\bu_\bn_\bt lines read.
- -\b-t\bt Remove a trailing _\bd_\be_\bl_\bi_\bm (default newline) from each line
+ -\b-t\bt Remove a trailing _\bd_\be_\bl_\bi_\bm (default newline) from each line
read.
- -\b-u\bu Read lines from file descriptor _\bf_\bd instead of the stan-
+ -\b-u\bu Read lines from file descriptor _\bf_\bd instead of the stan-
dard input.
- -\b-C\bC Evaluate _\bc_\ba_\bl_\bl_\bb_\ba_\bc_\bk each time _\bq_\bu_\ba_\bn_\bt_\bu_\bm lines are read. The
+ -\b-C\bC Evaluate _\bc_\ba_\bl_\bl_\bb_\ba_\bc_\bk each time _\bq_\bu_\ba_\bn_\bt_\bu_\bm lines are read. The
-\b-c\bc option specifies _\bq_\bu_\ba_\bn_\bt_\bu_\bm.
- -\b-c\bc Specify the number of lines read between each call to
+ -\b-c\bc Specify the number of lines read between each call to
_\bc_\ba_\bl_\bl_\bb_\ba_\bc_\bk.
- If -\b-C\bC is specified without -\b-c\bc, the default quantum is 5000.
+ If -\b-C\bC is specified without -\b-c\bc, the default quantum is 5000.
When _\bc_\ba_\bl_\bl_\bb_\ba_\bc_\bk is evaluated, it is supplied the index of the next
array element to be assigned and the line to be assigned to that
- element as additional arguments. _\bc_\ba_\bl_\bl_\bb_\ba_\bc_\bk is evaluated after
+ element as additional arguments. _\bc_\ba_\bl_\bl_\bb_\ba_\bc_\bk is evaluated after
the line is read but before the array element is assigned.
- If not supplied with an explicit origin, m\bma\bap\bpf\bfi\bil\ble\be will clear _\ba_\br_\b-
+ If not supplied with an explicit origin, m\bma\bap\bpf\bfi\bil\ble\be will clear _\ba_\br_\b-
_\br_\ba_\by before assigning to it.
m\bma\bap\bpf\bfi\bil\ble\be returns zero unless an invalid option or option argument
- is supplied, _\ba_\br_\br_\ba_\by is invalid or unassignable, or if _\ba_\br_\br_\ba_\by is
+ is supplied, _\ba_\br_\br_\ba_\by is invalid or unassignable, or if _\ba_\br_\br_\ba_\by is
not an indexed array.
p\bpo\bop\bpd\bd [-n\bn] [+_\bn] [-_\bn]
- Remove entries from the directory stack. The elements are num-
- bered from 0 starting at the first directory listed by d\bdi\bir\brs\bs, so
- p\bpo\bop\bpd\bd is equivalent to "popd +0." With no arguments, p\bpo\bop\bpd\bd re-
- moves the top directory from the stack, and changes to the new
+ Remove entries from the directory stack. The elements are num-
+ bered from 0 starting at the first directory listed by d\bdi\bir\brs\bs, so
+ p\bpo\bop\bpd\bd is equivalent to "popd +0." With no arguments, p\bpo\bop\bpd\bd re-
+ moves the top directory from the stack, and changes to the new
top directory. Arguments, if supplied, have the following mean-
ings:
-\b-n\bn Suppress the normal change of directory when removing di-
rectories from the stack, only manipulate the stack.
- +\b+_\bn Remove the _\bnth entry counting from the left of the list
- shown by d\bdi\bir\brs\bs, starting with zero, from the stack. For
+ +\b+_\bn Remove the _\bnth entry counting from the left of the list
+ shown by d\bdi\bir\brs\bs, starting with zero, from the stack. For
example: "popd +0" removes the first directory, "popd +1"
the second.
- -\b-_\bn Remove the _\bnth entry counting from the right of the list
- shown by d\bdi\bir\brs\bs, starting with zero. For example: "popd
- -0" removes the last directory, "popd -1" the next to
+ -\b-_\bn Remove the _\bnth entry counting from the right of the list
+ shown by d\bdi\bir\brs\bs, starting with zero. For example: "popd
+ -0" removes the last directory, "popd -1" the next to
last.
- If the top element of the directory stack is modified, and the
- -\b-n\bn option was not supplied, p\bpo\bop\bpd\bd uses the c\bcd\bd builtin to change
+ If the top element of the directory stack is modified, and the
+ -\b-n\bn option was not supplied, p\bpo\bop\bpd\bd uses the c\bcd\bd builtin to change
to the directory at the top of the stack. If the c\bcd\bd fails, p\bpo\bop\bpd\bd
returns a non-zero value.
- Otherwise, p\bpo\bop\bpd\bd returns false if an invalid option is supplied,
- the directory stack is empty, or _\bn specifies a non-existent di-
+ Otherwise, p\bpo\bop\bpd\bd returns false if an invalid option is supplied,
+ the directory stack is empty, or _\bn specifies a non-existent di-
rectory stack entry.
- If the p\bpo\bop\bpd\bd command is successful, b\bba\bas\bsh\bh runs d\bdi\bir\brs\bs to show the
- final contents of the directory stack, and the return status is
+ If the p\bpo\bop\bpd\bd command is successful, b\bba\bas\bsh\bh runs d\bdi\bir\brs\bs to show the
+ final contents of the directory stack, and the return status is
0.
p\bpr\bri\bin\bnt\btf\bf [-\b-v\bv _\bv_\ba_\br] _\bf_\bo_\br_\bm_\ba_\bt [_\ba_\br_\bg_\bu_\bm_\be_\bn_\bt_\bs]
- Write the formatted _\ba_\br_\bg_\bu_\bm_\be_\bn_\bt_\bs to the standard output under the
- control of the _\bf_\bo_\br_\bm_\ba_\bt. The -\b-v\bv option assigns the output to the
+ Write the formatted _\ba_\br_\bg_\bu_\bm_\be_\bn_\bt_\bs to the standard output under the
+ control of the _\bf_\bo_\br_\bm_\ba_\bt. The -\b-v\bv option assigns the output to the
variable _\bv_\ba_\br rather than printing it to the standard output.
- The _\bf_\bo_\br_\bm_\ba_\bt is a character string which contains three types of
- objects: plain characters, which are simply copied to standard
- output, character escape sequences, which are converted and
- copied to the standard output, and format specifications, each
- of which causes printing of the next successive _\ba_\br_\bg_\bu_\bm_\be_\bn_\bt. In
- addition to the standard _\bp_\br_\bi_\bn_\bt_\bf(3) format characters c\bcC\bCs\bsS\bS-\b-
+ The _\bf_\bo_\br_\bm_\ba_\bt is a character string which contains three types of
+ objects: plain characters, which are simply copied to standard
+ output, character escape sequences, which are converted and
+ copied to the standard output, and format specifications, each
+ of which causes printing of the next successive _\ba_\br_\bg_\bu_\bm_\be_\bn_\bt. In
+ addition to the standard _\bp_\br_\bi_\bn_\bt_\bf(3) format characters c\bcC\bCs\bsS\bS-\b-
n\bnd\bdi\bio\bou\bux\bxX\bXe\beE\bEf\bfF\bFg\bgG\bGa\baA\bA, p\bpr\bri\bin\bnt\btf\bf interprets the following additional for-
mat specifiers:
%\b%b\bb causes p\bpr\bri\bin\bnt\btf\bf to expand backslash escape sequences in the
corresponding _\ba_\br_\bg_\bu_\bm_\be_\bn_\bt in the same way as e\bec\bch\bho\bo -\b-e\be.
- %\b%q\bq causes p\bpr\bri\bin\bnt\btf\bf to output the corresponding _\ba_\br_\bg_\bu_\bm_\be_\bn_\bt in a
- format that can be reused as shell input. %\b%q\bq and %\b%Q\bQ use
- the $\b$'\b''\b' quoting style if any characters in the argument
- string require it, and backslash quoting otherwise. If
- the format string uses the _\bp_\br_\bi_\bn_\bt_\bf alternate form, these
+ %\b%q\bq causes p\bpr\bri\bin\bnt\btf\bf to output the corresponding _\ba_\br_\bg_\bu_\bm_\be_\bn_\bt in a
+ format that can be reused as shell input. %\b%q\bq and %\b%Q\bQ use
+ the $\b$'\b''\b' quoting style if any characters in the argument
+ string require it, and backslash quoting otherwise. If
+ the format string uses the _\bp_\br_\bi_\bn_\bt_\bf alternate form, these
two formats quote the argument string using single
quotes.
- %\b%Q\bQ like %\b%q\bq, but applies any supplied precision to the _\ba_\br_\bg_\bu_\b-
+ %\b%Q\bQ like %\b%q\bq, but applies any supplied precision to the _\ba_\br_\bg_\bu_\b-
_\bm_\be_\bn_\bt before quoting it.
%\b%(\b(_\bd_\ba_\bt_\be_\bf_\bm_\bt)\b)T\bT
- causes p\bpr\bri\bin\bnt\btf\bf to output the date-time string resulting
- from using _\bd_\ba_\bt_\be_\bf_\bm_\bt as a format string for _\bs_\bt_\br_\bf_\bt_\bi_\bm_\be(3).
+ causes p\bpr\bri\bin\bnt\btf\bf to output the date-time string resulting
+ from using _\bd_\ba_\bt_\be_\bf_\bm_\bt as a format string for _\bs_\bt_\br_\bf_\bt_\bi_\bm_\be(3).
The corresponding _\ba_\br_\bg_\bu_\bm_\be_\bn_\bt is an integer representing the
number of seconds since the epoch. This format specifier
recognizes two special argument values: -1 represents the
- current time, and -2 represents the time the shell was
+ current time, and -2 represents the time the shell was
invoked. If no argument is specified, conversion behaves
- as if -1 had been supplied. This is an exception to the
+ as if -1 had been supplied. This is an exception to the
usual p\bpr\bri\bin\bnt\btf\bf behavior.
The %b, %q, and %T format specifiers all use the field width and
precision arguments from the format specification and write that
- many bytes from (or use that wide a field for) the expanded ar-
- gument, which usually contains more characters than the origi-
+ many bytes from (or use that wide a field for) the expanded ar-
+ gument, which usually contains more characters than the origi-
nal.
The %n format specifier accepts a corresponding argument that is
treated as a shell variable name.
- The %s and %c format specifiers accept an l (long) modifier,
+ The %s and %c format specifiers accept an l (long) modifier,
which forces them to convert the argument string to a wide-char-
acter string and apply any supplied field width and precision in
terms of characters, not bytes. The %S and %C format specifiers
are equivalent to %ls and %lc, respectively.
- Arguments to non-string format specifiers are treated as C con-
+ Arguments to non-string format specifiers are treated as C con-
stants, except that a leading plus or minus sign is allowed, and
- if the leading character is a single or double quote, the value
- is the numeric value of the following character, using the cur-
+ if the leading character is a single or double quote, the value
+ is the numeric value of the following character, using the cur-
rent locale.
- Format specifiers may apply to the _\bnth argument rather than the
- next sequential argument. In this case, the '%' in the format
- specifier is replaced by the sequence "%_\bn$", where _\bn is a deci-
+ Format specifiers may apply to the _\bnth argument rather than the
+ next sequential argument. In this case, the '%' in the format
+ specifier is replaced by the sequence "%_\bn$", where _\bn is a deci-
mal integer greater than 0, giving the argument number to use as
- the operand. The format string should not mix numbered and un-
- numbered argument specifiers, though this is allowed. Unnum-
+ the operand. The format string should not mix numbered and un-
+ numbered argument specifiers, though this is allowed. Unnum-
bered argument specifiers always refer to the next argument fol-
- lowing the last argument consumed by an unnumbered specifier;
- numbered argument specifiers refer to absolute positions in the
+ lowing the last argument consumed by an unnumbered specifier;
+ numbered argument specifiers refer to absolute positions in the
argument list.
- The _\bf_\bo_\br_\bm_\ba_\bt is reused as necessary to consume all of the _\ba_\br_\bg_\bu_\b-
+ The _\bf_\bo_\br_\bm_\ba_\bt is reused as necessary to consume all of the _\ba_\br_\bg_\bu_\b-
_\bm_\be_\bn_\bt_\bs. If the _\bf_\bo_\br_\bm_\ba_\bt requires more _\ba_\br_\bg_\bu_\bm_\be_\bn_\bt_\bs than are supplied,
- the extra format specifications behave as if a zero value or
- null string, as appropriate, had been supplied. If _\bf_\bo_\br_\bm_\ba_\bt is
- reused, a numbered argument specifier "%_\bn$" refers to the _\bnth
+ the extra format specifications behave as if a zero value or
+ null string, as appropriate, had been supplied. If _\bf_\bo_\br_\bm_\ba_\bt is
+ reused, a numbered argument specifier "%_\bn$" refers to the _\bnth
argument following the highest numbered argument consumed by the
previous use of _\bf_\bo_\br_\bm_\ba_\bt.
- The return value is zero on success, non-zero if an invalid op-
+ The return value is zero on success, non-zero if an invalid op-
tion is supplied or a write or assignment error occurs.
p\bpu\bus\bsh\bhd\bd [-\b-n\bn] [+_\bn] [-_\bn]
p\bpu\bus\bsh\bhd\bd [-\b-n\bn] [_\bd_\bi_\br]
Add a directory to the top of the directory stack, or rotate the
- stack, making the new top of the stack the current working di-
- rectory. With no arguments, p\bpu\bus\bsh\bhd\bd exchanges the top two ele-
- ments of the directory stack. Arguments, if supplied, have the
+ stack, making the new top of the stack the current working di-
+ rectory. With no arguments, p\bpu\bus\bsh\bhd\bd exchanges the top two ele-
+ ments of the directory stack. Arguments, if supplied, have the
following meanings:
- -\b-n\bn Suppress the normal change of directory when rotating or
- adding directories to the stack, only manipulate the
+ -\b-n\bn Suppress the normal change of directory when rotating or
+ adding directories to the stack, only manipulate the
stack.
+\b+_\bn Rotate the stack so that the _\bnth directory (counting from
- the left of the list shown by d\bdi\bir\brs\bs, starting with zero)
+ the left of the list shown by d\bdi\bir\brs\bs, starting with zero)
is at the top.
- -\b-_\bn Rotates the stack so that the _\bnth directory (counting
- from the right of the list shown by d\bdi\bir\brs\bs, starting with
+ -\b-_\bn Rotates the stack so that the _\bnth directory (counting
+ from the right of the list shown by d\bdi\bir\brs\bs, starting with
zero) is at the top.
_\bd_\bi_\br Adds _\bd_\bi_\br to the directory stack at the top.
After the stack has been modified, if the -\b-n\bn option was not sup-
- plied, p\bpu\bus\bsh\bhd\bd uses the c\bcd\bd builtin to change to the directory at
+ plied, p\bpu\bus\bsh\bhd\bd uses the c\bcd\bd builtin to change to the directory at
the top of the stack. If the c\bcd\bd fails, p\bpu\bus\bsh\bhd\bd returns a non-zero
value.
- Otherwise, if no arguments are supplied, p\bpu\bus\bsh\bhd\bd returns zero un-
- less the directory stack is empty. When rotating the directory
+ Otherwise, if no arguments are supplied, p\bpu\bus\bsh\bhd\bd returns zero un-
+ less the directory stack is empty. When rotating the directory
stack, p\bpu\bus\bsh\bhd\bd returns zero unless the directory stack is empty or
_\bn specifies a non-existent directory stack element.
- If the p\bpu\bus\bsh\bhd\bd command is successful, b\bba\bas\bsh\bh runs d\bdi\bir\brs\bs to show the
+ If the p\bpu\bus\bsh\bhd\bd command is successful, b\bba\bas\bsh\bh runs d\bdi\bir\brs\bs to show the
final contents of the directory stack.
p\bpw\bwd\bd [-\b-L\bLP\bP]
- Print the absolute pathname of the current working directory.
+ Print the absolute pathname of the current working directory.
The pathname printed contains no symbolic links if the -\b-P\bP option
is supplied or the -\b-o\bo p\bph\bhy\bys\bsi\bic\bca\bal\bl option to the s\bse\bet\bt builtin command
- is enabled. If the -\b-L\bL option is used, the pathname printed may
- contain symbolic links. The return status is 0 unless an error
+ is enabled. If the -\b-L\bL option is used, the pathname printed may
+ contain symbolic links. The return status is 0 unless an error
occurs while reading the name of the current directory or an in-
valid option is supplied.
r\bre\bea\bad\bd [-\b-E\bEe\ber\brs\bs] [-\b-a\ba _\ba_\bn_\ba_\bm_\be] [-\b-d\bd _\bd_\be_\bl_\bi_\bm] [-\b-i\bi _\bt_\be_\bx_\bt] [-\b-n\bn _\bn_\bc_\bh_\ba_\br_\bs] [-\b-N\bN _\bn_\bc_\bh_\ba_\br_\bs]
[-\b-p\bp _\bp_\br_\bo_\bm_\bp_\bt] [-\b-t\bt _\bt_\bi_\bm_\be_\bo_\bu_\bt] [-\b-u\bu _\bf_\bd] [_\bn_\ba_\bm_\be ...]
Read one line from the standard input, or from the file descrip-
- tor _\bf_\bd supplied as an argument to the -\b-u\bu option, split it into
- words as described above under W\bWo\bor\brd\bd S\bSp\bpl\bli\bit\btt\bti\bin\bng\bg, and assign the
- first word to the first _\bn_\ba_\bm_\be, the second word to the second
- _\bn_\ba_\bm_\be, and so on. If there are more words than names, the re-
- maining words and their intervening delimiters are assigned to
- the last _\bn_\ba_\bm_\be. If there are fewer words read from the input
- stream than names, the remaining names are assigned empty val-
- ues. The characters in the value of the I\bIF\bFS\bS variable are used
+ tor _\bf_\bd supplied as an argument to the -\b-u\bu option, split it into
+ words as described above under W\bWo\bor\brd\bd S\bSp\bpl\bli\bit\btt\bti\bin\bng\bg, and assign the
+ first word to the first _\bn_\ba_\bm_\be, the second word to the second
+ _\bn_\ba_\bm_\be, and so on. If there are more words than names, the re-
+ maining words and their intervening delimiters are assigned to
+ the last _\bn_\ba_\bm_\be. If there are fewer words read from the input
+ stream than names, the remaining names are assigned empty val-
+ ues. The characters in the value of the I\bIF\bFS\bS variable are used
to split the line into words using the same rules the shell uses
for expansion (described above under W\bWo\bor\brd\bd S\bSp\bpl\bli\bit\btt\bti\bin\bng\bg). The back-
- slash character (\\b\) removes any special meaning for the next
+ slash character (\\b\) removes any special meaning for the next
character read and is used for line continuation.
Options, if supplied, have the following meanings:
-\b-a\ba _\ba_\bn_\ba_\bm_\be
The words are assigned to sequential indices of the array
variable _\ba_\bn_\ba_\bm_\be, starting at 0. _\ba_\bn_\ba_\bm_\be is unset before any
- new values are assigned. Other _\bn_\ba_\bm_\be arguments are ig-
+ new values are assigned. Other _\bn_\ba_\bm_\be arguments are ig-
nored.
-\b-d\bd _\bd_\be_\bl_\bi_\bm
- The first character of _\bd_\be_\bl_\bi_\bm terminates the input line,
- rather than newline. If _\bd_\be_\bl_\bi_\bm is the empty string, r\bre\bea\bad\bd
+ The first character of _\bd_\be_\bl_\bi_\bm terminates the input line,
+ rather than newline. If _\bd_\be_\bl_\bi_\bm is the empty string, r\bre\bea\bad\bd
will terminate a line when it reads a NUL character.
- -\b-e\be If the standard input is coming from a terminal, r\bre\bea\bad\bd
- uses r\bre\bea\bad\bdl\bli\bin\bne\be (see R\bRE\bEA\bAD\bDL\bLI\bIN\bNE\bE above) to obtain the line.
- R\bRe\bea\bad\bdl\bli\bin\bne\be uses the current (or default, if line editing
- was not previously active) editing settings, but uses
+ -\b-e\be If the standard input is coming from a terminal, r\bre\bea\bad\bd
+ uses r\bre\bea\bad\bdl\bli\bin\bne\be (see R\bRE\bEA\bAD\bDL\bLI\bIN\bNE\bE above) to obtain the line.
+ R\bRe\bea\bad\bdl\bli\bin\bne\be uses the current (or default, if line editing
+ was not previously active) editing settings, but uses
r\bre\bea\bad\bdl\bli\bin\bne\be's default filename completion.
- -\b-E\bE If the standard input is coming from a terminal, r\bre\bea\bad\bd
- uses r\bre\bea\bad\bdl\bli\bin\bne\be (see R\bRE\bEA\bAD\bDL\bLI\bIN\bNE\bE above) to obtain the line.
- R\bRe\bea\bad\bdl\bli\bin\bne\be uses the current (or default, if line editing
- was not previously active) editing settings, but uses
+ -\b-E\bE If the standard input is coming from a terminal, r\bre\bea\bad\bd
+ uses r\bre\bea\bad\bdl\bli\bin\bne\be (see R\bRE\bEA\bAD\bDL\bLI\bIN\bNE\bE above) to obtain the line.
+ R\bRe\bea\bad\bdl\bli\bin\bne\be uses the current (or default, if line editing
+ was not previously active) editing settings, but uses
bash's default completion, including programmable comple-
tion.
-\b-i\bi _\bt_\be_\bx_\bt
- If r\bre\bea\bad\bdl\bli\bin\bne\be is being used to read the line, r\bre\bea\bad\bd places
+ If r\bre\bea\bad\bdl\bli\bin\bne\be is being used to read the line, r\bre\bea\bad\bd places
_\bt_\be_\bx_\bt into the editing buffer before editing begins.
-\b-n\bn _\bn_\bc_\bh_\ba_\br_\bs
- r\bre\bea\bad\bd returns after reading _\bn_\bc_\bh_\ba_\br_\bs characters rather than
- waiting for a complete line of input, unless it encoun-
- ters EOF or r\bre\bea\bad\bd times out, but honors a delimiter if it
+ r\bre\bea\bad\bd returns after reading _\bn_\bc_\bh_\ba_\br_\bs characters rather than
+ waiting for a complete line of input, unless it encoun-
+ ters EOF or r\bre\bea\bad\bd times out, but honors a delimiter if it
reads fewer than _\bn_\bc_\bh_\ba_\br_\bs characters before the delimiter.
-\b-N\bN _\bn_\bc_\bh_\ba_\br_\bs
- r\bre\bea\bad\bd returns after reading exactly _\bn_\bc_\bh_\ba_\br_\bs characters
- rather than waiting for a complete line of input, unless
+ r\bre\bea\bad\bd returns after reading exactly _\bn_\bc_\bh_\ba_\br_\bs characters
+ rather than waiting for a complete line of input, unless
it encounters EOF or r\bre\bea\bad\bd times out. Any delimiter char-
- acters in the input are not treated specially and do not
+ acters in the input are not treated specially and do not
cause r\bre\bea\bad\bd to return until it has read _\bn_\bc_\bh_\ba_\br_\bs characters.
The result is not split on the characters in I\bIF\bFS\bS; the in-
tent is that the variable is assigned exactly the charac-
- ters read (with the exception of backslash; see the -\b-r\br
+ ters read (with the exception of backslash; see the -\b-r\br
option below).
-\b-p\bp _\bp_\br_\bo_\bm_\bp_\bt
Display _\bp_\br_\bo_\bm_\bp_\bt on standard error, without a trailing new-
- line, before attempting to read any input, but only if
+ line, before attempting to read any input, but only if
input is coming from a terminal.
-\b-r\br Backslash does not act as an escape character. The back-
- slash is considered to be part of the line. In particu-
- lar, a backslash-newline pair may not then be used as a
+ slash is considered to be part of the line. In particu-
+ lar, a backslash-newline pair may not then be used as a
line continuation.
-\b-s\bs Silent mode. If input is coming from a terminal, charac-
ters are not echoed.
-\b-t\bt _\bt_\bi_\bm_\be_\bo_\bu_\bt
- Cause r\bre\bea\bad\bd to time out and return failure if it does not
- read a complete line of input (or a specified number of
- characters) within _\bt_\bi_\bm_\be_\bo_\bu_\bt seconds. _\bt_\bi_\bm_\be_\bo_\bu_\bt may be a
- decimal number with a fractional portion following the
- decimal point. This option is only effective if r\bre\bea\bad\bd is
- reading input from a terminal, pipe, or other special
- file; it has no effect when reading from regular files.
- If r\bre\bea\bad\bd times out, it saves any partial input read into
- the specified variable _\bn_\ba_\bm_\be, and the exit status is
- greater than 128. If _\bt_\bi_\bm_\be_\bo_\bu_\bt is 0, r\bre\bea\bad\bd returns immedi-
- ately, without trying to read any data. In this case,
- the exit status is 0 if input is available on the speci-
- fied file descriptor, or the read will return EOF, non-
+ Cause r\bre\bea\bad\bd to time out and return failure if it does not
+ read a complete line of input (or a specified number of
+ characters) within _\bt_\bi_\bm_\be_\bo_\bu_\bt seconds. _\bt_\bi_\bm_\be_\bo_\bu_\bt may be a
+ decimal number with a fractional portion following the
+ decimal point. This option is only effective if r\bre\bea\bad\bd is
+ reading input from a terminal, pipe, or other special
+ file; it has no effect when reading from regular files.
+ If r\bre\bea\bad\bd times out, it saves any partial input read into
+ the specified variable _\bn_\ba_\bm_\be, and the exit status is
+ greater than 128. If _\bt_\bi_\bm_\be_\bo_\bu_\bt is 0, r\bre\bea\bad\bd returns immedi-
+ ately, without trying to read any data. In this case,
+ the exit status is 0 if input is available on the speci-
+ fied file descriptor, or the read will return EOF, non-
zero otherwise.
- -\b-u\bu _\bf_\bd Read input from file descriptor _\bf_\bd instead of the stan-
+ -\b-u\bu _\bf_\bd Read input from file descriptor _\bf_\bd instead of the stan-
dard input.
- Other than the case where _\bd_\be_\bl_\bi_\bm is the empty string, r\bre\bea\bad\bd ig-
+ Other than the case where _\bd_\be_\bl_\bi_\bm is the empty string, r\bre\bea\bad\bd ig-
nores any NUL characters in the input.
- If no _\bn_\ba_\bm_\be_\bs are supplied, r\bre\bea\bad\bd assigns the line read, without
- the ending delimiter but otherwise unmodified, to the variable
+ If no _\bn_\ba_\bm_\be_\bs are supplied, r\bre\bea\bad\bd assigns the line read, without
+ the ending delimiter but otherwise unmodified, to the variable
R\bRE\bEP\bPL\bLY\bY.
The exit status is zero, unless end-of-file is encountered, r\bre\bea\bad\bd
- times out (in which case the status is greater than 128), a
+ times out (in which case the status is greater than 128), a
variable assignment error (such as assigning to a readonly vari-
- able) occurs, or an invalid file descriptor is supplied as the
+ able) occurs, or an invalid file descriptor is supplied as the
argument to -\b-u\bu.
r\bre\bea\bad\bdo\bon\bnl\bly\by [-\b-a\baA\bAf\bf] [-\b-p\bp] [_\bn_\ba_\bm_\be[=_\bw_\bo_\br_\bd] ...]
- The given _\bn_\ba_\bm_\be_\bs are marked readonly; the values of these _\bn_\ba_\bm_\be_\bs
+ The given _\bn_\ba_\bm_\be_\bs are marked readonly; the values of these _\bn_\ba_\bm_\be_\bs
may not be changed by subsequent assignment or unset. If the -\b-f\bf
- option is supplied, each _\bn_\ba_\bm_\be refers to a shell function. The
- -\b-a\ba option restricts the variables to indexed arrays; the -\b-A\bA op-
+ option is supplied, each _\bn_\ba_\bm_\be refers to a shell function. The
+ -\b-a\ba option restricts the variables to indexed arrays; the -\b-A\bA op-
tion restricts the variables to associative arrays. If both op-
- tions are supplied, -\b-A\bA takes precedence. If no _\bn_\ba_\bm_\be arguments
- are supplied, or if the -\b-p\bp option is supplied, print a list of
- all readonly names. The other options may be used to restrict
+ tions are supplied, -\b-A\bA takes precedence. If no _\bn_\ba_\bm_\be arguments
+ are supplied, or if the -\b-p\bp option is supplied, print a list of
+ all readonly names. The other options may be used to restrict
the output to a subset of the set of readonly names. The -\b-p\bp op-
tion displays output in a format that may be reused as input.
- r\bre\bea\bad\bdo\bon\bnl\bly\by allows the value of a variable to be set at the same
+ r\bre\bea\bad\bdo\bon\bnl\bly\by allows the value of a variable to be set at the same
time the readonly attribute is changed by following the variable
- name with =_\bv_\ba_\bl_\bu_\be. This sets the value of the variable is to
+ name with =_\bv_\ba_\bl_\bu_\be. This sets the value of the variable is to
_\bv_\ba_\bl_\bu_\be while modifying the readonly attribute.
- The return status is 0 unless an invalid option is encountered,
- one of the _\bn_\ba_\bm_\be_\bs is not a valid shell variable name, or -\b-f\bf is
+ The return status is 0 unless an invalid option is encountered,
+ one of the _\bn_\ba_\bm_\be_\bs is not a valid shell variable name, or -\b-f\bf is
supplied with a _\bn_\ba_\bm_\be that is not a function.
r\bre\bet\btu\bur\brn\bn [_\bn]
- Stop executing a shell function or sourced file and return the
+ Stop executing a shell function or sourced file and return the
value specified by _\bn to its caller. If _\bn is omitted, the return
- status is that of the last command executed. If r\bre\bet\btu\bur\brn\bn is exe-
- cuted by a trap handler, the last command used to determine the
+ status is that of the last command executed. If r\bre\bet\btu\bur\brn\bn is exe-
+ cuted by a trap handler, the last command used to determine the
status is the last command executed before the trap handler. If
r\bre\bet\btu\bur\brn\bn is executed during a D\bDE\bEB\bBU\bUG\bG trap, the last command used to
- determine the status is the last command executed by the trap
+ determine the status is the last command executed by the trap
handler before r\bre\bet\btu\bur\brn\bn was invoked.
When r\bre\bet\btu\bur\brn\bn is used to terminate execution of a script being ex-
- ecuted by the .\b. (s\bso\bou\bur\brc\bce\be) command, it causes the shell to stop
- executing that script and return either _\bn or the exit status of
- the last command executed within the script as the exit status
- of the script. If _\bn is supplied, the return value is its least
+ ecuted by the .\b. (s\bso\bou\bur\brc\bce\be) command, it causes the shell to stop
+ executing that script and return either _\bn or the exit status of
+ the last command executed within the script as the exit status
+ of the script. If _\bn is supplied, the return value is its least
significant 8 bits.
- Any command associated with the R\bRE\bET\bTU\bUR\bRN\bN trap is executed before
+ Any command associated with the R\bRE\bET\bTU\bUR\bRN\bN trap is executed before
execution resumes after the function or script.
- The return status is non-zero if r\bre\bet\btu\bur\brn\bn is supplied a non-nu-
+ The return status is non-zero if r\bre\bet\btu\bur\brn\bn is supplied a non-nu-
meric argument, or is used outside a function and not during ex-
ecution of a script by .\b. or s\bso\bou\bur\brc\bce\be.
s\bse\bet\bt [-\b-a\bab\bbe\bef\bfh\bhk\bkm\bmn\bnp\bpt\btu\buv\bvx\bxB\bBC\bCE\bEH\bHP\bPT\bT] [-\b-o\bo _\bo_\bp_\bt_\bi_\bo_\bn_\b-_\bn_\ba_\bm_\be] [-\b--\b-] [-\b-] [_\ba_\br_\bg ...]
s\bse\bet\bt [+\b+a\bab\bbe\bef\bfh\bhk\bkm\bmn\bnp\bpt\btu\buv\bvx\bxB\bBC\bCE\bEH\bHP\bPT\bT] [+\b+o\bo _\bo_\bp_\bt_\bi_\bo_\bn_\b-_\bn_\ba_\bm_\be] [-\b--\b-] [-\b-] [_\ba_\br_\bg ...]
s\bse\bet\bt -\b-o\bo
- s\bse\bet\bt +\b+o\bo Without options, display the name and value of each shell vari-
- able in a format that can be reused as input for setting or re-
+ s\bse\bet\bt +\b+o\bo Without options, display the name and value of each shell vari-
+ able in a format that can be reused as input for setting or re-
setting the currently-set variables. Read-only variables cannot
- be reset. In posix mode, only shell variables are listed. The
- output is sorted according to the current locale. When options
- are specified, they set or unset shell attributes. Any argu-
- ments remaining after option processing are treated as values
+ be reset. In posix mode, only shell variables are listed. The
+ output is sorted according to the current locale. When options
+ are specified, they set or unset shell attributes. Any argu-
+ ments remaining after option processing are treated as values
for the positional parameters and are assigned, in order, to $\b$1\b1,
- $\b$2\b2, ..., $\b$_\bn. Options, if specified, have the following mean-
+ $\b$2\b2, ..., $\b$_\bn. Options, if specified, have the following mean-
ings:
-\b-a\ba Each variable or function that is created or modified is
- given the export attribute and marked for export to the
+ given the export attribute and marked for export to the
environment of subsequent commands.
- -\b-b\bb Report the status of terminated background jobs immedi-
+ -\b-b\bb Report the status of terminated background jobs immedi-
ately, rather than before the next primary prompt or af-
- ter a foreground command terminates. This is effective
+ ter a foreground command terminates. This is effective
only when job control is enabled.
- -\b-e\be Exit immediately if a _\bp_\bi_\bp_\be_\bl_\bi_\bn_\be (which may consist of a
- single _\bs_\bi_\bm_\bp_\bl_\be _\bc_\bo_\bm_\bm_\ba_\bn_\bd), a _\bl_\bi_\bs_\bt, or a _\bc_\bo_\bm_\bp_\bo_\bu_\bn_\bd _\bc_\bo_\bm_\bm_\ba_\bn_\bd
+ -\b-e\be Exit immediately if a _\bp_\bi_\bp_\be_\bl_\bi_\bn_\be (which may consist of a
+ single _\bs_\bi_\bm_\bp_\bl_\be _\bc_\bo_\bm_\bm_\ba_\bn_\bd), a _\bl_\bi_\bs_\bt, or a _\bc_\bo_\bm_\bp_\bo_\bu_\bn_\bd _\bc_\bo_\bm_\bm_\ba_\bn_\bd
(see S\bSH\bHE\bEL\bLL\bL G\bGR\bRA\bAM\bMM\bMA\bAR\bR above), exits with a non-zero status.
- The shell does not exit if the command that fails is
- part of the command list immediately following a w\bwh\bhi\bil\ble\be
- or u\bun\bnt\bti\bil\bl reserved word, part of the test following the
- i\bif\bf or e\bel\bli\bif\bf reserved words, part of any command executed
- in a &\b&&\b& or |\b||\b| list except the command following the fi-
- nal &\b&&\b& or |\b||\b|, any command in a pipeline but the last
- (subject to the state of the p\bpi\bip\bpe\bef\bfa\bai\bil\bl shell option), or
- if the command's return value is being inverted with !\b!.
- If a compound command other than a subshell returns a
- non-zero status because a command failed while -\b-e\be was
- being ignored, the shell does not exit. A trap on E\bER\bRR\bR,
+ The shell does not exit if the command that fails is
+ part of the command list immediately following a w\bwh\bhi\bil\ble\be
+ or u\bun\bnt\bti\bil\bl reserved word, part of the test following the
+ i\bif\bf or e\bel\bli\bif\bf reserved words, part of any command executed
+ in a &\b&&\b& or |\b||\b| list except the command following the fi-
+ nal &\b&&\b& or |\b||\b|, any command in a pipeline but the last
+ (subject to the state of the p\bpi\bip\bpe\bef\bfa\bai\bil\bl shell option), or
+ if the command's return value is being inverted with !\b!.
+ If a compound command other than a subshell returns a
+ non-zero status because a command failed while -\b-e\be was
+ being ignored, the shell does not exit. A trap on E\bER\bRR\bR,
if set, is executed before the shell exits. This option
applies to the shell environment and each subshell envi-
- ronment separately (see C\bCO\bOM\bMM\bMA\bAN\bND\bD E\bEX\bXE\bEC\bCU\bUT\bTI\bIO\bON\bN E\bEN\bNV\bVI\bIR\bRO\bON\bNM\bME\bEN\bNT\bT
+ ronment separately (see C\bCO\bOM\bMM\bMA\bAN\bND\bD E\bEX\bXE\bEC\bCU\bUT\bTI\bIO\bON\bN E\bEN\bNV\bVI\bIR\bRO\bON\bNM\bME\bEN\bNT\bT
above), and may cause subshells to exit before executing
all the commands in the subshell.
- If a compound command or shell function executes in a
- context where -\b-e\be is being ignored, none of the commands
- executed within the compound command or function body
- will be affected by the -\b-e\be setting, even if -\b-e\be is set
- and a command returns a failure status. If a compound
- command or shell function sets -\b-e\be while executing in a
- context where -\b-e\be is ignored, that setting will not have
- any effect until the compound command or the command
+ If a compound command or shell function executes in a
+ context where -\b-e\be is being ignored, none of the commands
+ executed within the compound command or function body
+ will be affected by the -\b-e\be setting, even if -\b-e\be is set
+ and a command returns a failure status. If a compound
+ command or shell function sets -\b-e\be while executing in a
+ context where -\b-e\be is ignored, that setting will not have
+ any effect until the compound command or the command
containing the function call completes.
-\b-f\bf Disable pathname expansion.
- -\b-h\bh Remember the location of commands as they are looked up
+ -\b-h\bh Remember the location of commands as they are looked up
for execution. This is enabled by default.
- -\b-k\bk All arguments in the form of assignment statements are
- placed in the environment for a command, not just those
+ -\b-k\bk All arguments in the form of assignment statements are
+ placed in the environment for a command, not just those
that precede the command name.
- -\b-m\bm Monitor mode. Job control is enabled. This option is
- on by default for interactive shells on systems that
- support it (see J\bJO\bOB\bB C\bCO\bON\bNT\bTR\bRO\bOL\bL above). All processes run
+ -\b-m\bm Monitor mode. Job control is enabled. This option is
+ on by default for interactive shells on systems that
+ support it (see J\bJO\bOB\bB C\bCO\bON\bNT\bTR\bRO\bOL\bL above). All processes run
in a separate process group. When a background job com-
pletes, the shell prints a line containing its exit sta-
tus.
-\b-n\bn Read commands but do not execute them. This may be used
- to check a shell script for syntax errors. This is ig-
+ to check a shell script for syntax errors. This is ig-
nored by interactive shells.
-\b-o\bo _\bo_\bp_\bt_\bi_\bo_\bn_\b-_\bn_\ba_\bm_\be
The _\bo_\bp_\bt_\bi_\bo_\bn_\b-_\bn_\ba_\bm_\be can be one of the following:
Same as -\b-a\ba.
b\bbr\bra\bac\bce\bee\bex\bxp\bpa\ban\bnd\bd
Same as -\b-B\bB.
- e\bem\bma\bac\bcs\bs Use an emacs-style command line editing inter-
+ e\bem\bma\bac\bcs\bs Use an emacs-style command line editing inter-
face. This is enabled by default when the shell
is interactive, unless the shell is started with
- the -\b--\b-n\bno\boe\bed\bdi\bit\bti\bin\bng\bg option. This also affects the
+ the -\b--\b-n\bno\boe\bed\bdi\bit\bti\bin\bng\bg option. This also affects the
editing interface used for r\bre\bea\bad\bd -\b-e\be.
e\ber\brr\bre\bex\bxi\bit\bt Same as -\b-e\be.
e\ber\brr\brt\btr\bra\bac\bce\be
H\bHI\bIS\bST\bTO\bOR\bRY\bY. This option is on by default in inter-
active shells.
i\big\bgn\bno\bor\bre\bee\beo\bof\bf
- The effect is as if the shell command
+ The effect is as if the shell command
"IGNOREEOF=10" had been executed (see S\bSh\bhe\bel\bll\bl
V\bVa\bar\bri\bia\bab\bbl\ble\bes\bs above).
k\bke\bey\byw\bwo\bor\brd\bd Same as -\b-k\bk.
p\bph\bhy\bys\bsi\bic\bca\bal\bl
Same as -\b-P\bP.
p\bpi\bip\bpe\bef\bfa\bai\bil\bl
- If set, the return value of a pipeline is the
- value of the last (rightmost) command to exit
- with a non-zero status, or zero if all commands
- in the pipeline exit successfully. This option
+ If set, the return value of a pipeline is the
+ value of the last (rightmost) command to exit
+ with a non-zero status, or zero if all commands
+ in the pipeline exit successfully. This option
is disabled by default.
- p\bpo\bos\bsi\bix\bx Enable posix mode; change the behavior of b\bba\bas\bsh\bh
- where the default operation differs from the
- POSIX standard to match the standard. See S\bSE\bEE\bE
- A\bAL\bLS\bSO\bO below for a reference to a document that
+ p\bpo\bos\bsi\bix\bx Enable posix mode; change the behavior of b\bba\bas\bsh\bh
+ where the default operation differs from the
+ POSIX standard to match the standard. See S\bSE\bEE\bE
+ A\bAL\bLS\bSO\bO below for a reference to a document that
details how posix mode affects bash's behavior.
p\bpr\bri\biv\bvi\bil\ble\beg\bge\bed\bd
Same as -\b-p\bp.
v\bve\ber\brb\bbo\bos\bse\be Same as -\b-v\bv.
- v\bvi\bi Use a vi-style command line editing interface.
+ v\bvi\bi Use a vi-style command line editing interface.
This also affects the editing interface used for
r\bre\bea\bad\bd -\b-e\be.
x\bxt\btr\bra\bac\bce\be Same as -\b-x\bx.
- If -\b-o\bo is supplied with no _\bo_\bp_\bt_\bi_\bo_\bn_\b-_\bn_\ba_\bm_\be, s\bse\bet\bt prints the
- current shell option settings. If +\b+o\bo is supplied with
- no _\bo_\bp_\bt_\bi_\bo_\bn_\b-_\bn_\ba_\bm_\be, s\bse\bet\bt prints a series of s\bse\bet\bt commands to
- recreate the current option settings on the standard
+ If -\b-o\bo is supplied with no _\bo_\bp_\bt_\bi_\bo_\bn_\b-_\bn_\ba_\bm_\be, s\bse\bet\bt prints the
+ current shell option settings. If +\b+o\bo is supplied with
+ no _\bo_\bp_\bt_\bi_\bo_\bn_\b-_\bn_\ba_\bm_\be, s\bse\bet\bt prints a series of s\bse\bet\bt commands to
+ recreate the current option settings on the standard
output.
- -\b-p\bp Turn on _\bp_\br_\bi_\bv_\bi_\bl_\be_\bg_\be_\bd mode. In this mode, the shell does
- not read the $\b$E\bEN\bNV\bV and $\b$B\bBA\bAS\bSH\bH_\b_E\bEN\bNV\bV files, shell functions
- are not inherited from the environment, and the S\bSH\bHE\bEL\bL-\b-
- L\bLO\bOP\bPT\bTS\bS, B\bBA\bAS\bSH\bHO\bOP\bPT\bTS\bS, C\bCD\bDP\bPA\bAT\bTH\bH, and G\bGL\bLO\bOB\bBI\bIG\bGN\bNO\bOR\bRE\bE variables, if
- they appear in the environment, are ignored. If the
- shell is started with the effective user (group) id not
- equal to the real user (group) id, and the -\b-p\bp option is
- not supplied, these actions are taken and the effective
+ -\b-p\bp Turn on _\bp_\br_\bi_\bv_\bi_\bl_\be_\bg_\be_\bd mode. In this mode, the shell does
+ not read the $\b$E\bEN\bNV\bV and $\b$B\bBA\bAS\bSH\bH_\b_E\bEN\bNV\bV files, shell functions
+ are not inherited from the environment, and the S\bSH\bHE\bEL\bL-\b-
+ L\bLO\bOP\bPT\bTS\bS, B\bBA\bAS\bSH\bHO\bOP\bPT\bTS\bS, C\bCD\bDP\bPA\bAT\bTH\bH, and G\bGL\bLO\bOB\bBI\bIG\bGN\bNO\bOR\bRE\bE variables, if
+ they appear in the environment, are ignored. If the
+ shell is started with the effective user (group) id not
+ equal to the real user (group) id, and the -\b-p\bp option is
+ not supplied, these actions are taken and the effective
user id is set to the real user id. If the -\b-p\bp option is
supplied at startup, the effective user id is not reset.
- Turning this option off causes the effective user and
+ Turning this option off causes the effective user and
group ids to be set to the real user and group ids.
-\b-r\br Enable restricted shell mode. This option cannot be un-
set once it has been set.
-\b-t\bt Exit after reading and executing one command.
-\b-u\bu Treat unset variables and parameters other than the spe-
- cial parameters "@" and "*", or array variables sub-
- scripted with "@" or "*", as an error when performing
- parameter expansion. If expansion is attempted on an
- unset variable or parameter, the shell prints an error
- message, and, if not interactive, exits with a non-zero
+ cial parameters "@" and "*", or array variables sub-
+ scripted with "@" or "*", as an error when performing
+ parameter expansion. If expansion is attempted on an
+ unset variable or parameter, the shell prints an error
+ message, and, if not interactive, exits with a non-zero
status.
-\b-v\bv Print shell input lines as they are read.
- -\b-x\bx After expanding each _\bs_\bi_\bm_\bp_\bl_\be _\bc_\bo_\bm_\bm_\ba_\bn_\bd, f\bfo\bor\br command, c\bca\bas\bse\be
+ -\b-x\bx After expanding each _\bs_\bi_\bm_\bp_\bl_\be _\bc_\bo_\bm_\bm_\ba_\bn_\bd, f\bfo\bor\br command, c\bca\bas\bse\be
command, s\bse\bel\ble\bec\bct\bt command, or arithmetic f\bfo\bor\br command, dis-
- play the expanded value of P\bPS\bS4\b4, followed by the command
- and its expanded arguments or associated word list, to
+ play the expanded value of P\bPS\bS4\b4, followed by the command
+ and its expanded arguments or associated word list, to
the standard error.
- -\b-B\bB The shell performs brace expansion (see B\bBr\bra\bac\bce\be E\bEx\bxp\bpa\ban\bns\bsi\bio\bon\bn
+ -\b-B\bB The shell performs brace expansion (see B\bBr\bra\bac\bce\be E\bEx\bxp\bpa\ban\bns\bsi\bio\bon\bn
above). This is on by default.
- -\b-C\bC If set, b\bba\bas\bsh\bh does not overwrite an existing file with
- the >\b>, >\b>&\b&, and <\b<>\b> redirection operators. Using the
- redirection operator >\b>|\b| instead of >\b> will override this
+ -\b-C\bC If set, b\bba\bas\bsh\bh does not overwrite an existing file with
+ the >\b>, >\b>&\b&, and <\b<>\b> redirection operators. Using the
+ redirection operator >\b>|\b| instead of >\b> will override this
and force the creation of an output file.
-\b-E\bE If set, any trap on E\bER\bRR\bR is inherited by shell functions,
- command substitutions, and commands executed in a sub-
- shell environment. The E\bER\bRR\bR trap is normally not inher-
+ command substitutions, and commands executed in a sub-
+ shell environment. The E\bER\bRR\bR trap is normally not inher-
ited in such cases.
-\b-H\bH Enable !\b! style history substitution. This option is on
by default when the shell is interactive.
- -\b-P\bP If set, the shell does not resolve symbolic links when
- executing commands such as c\bcd\bd that change the current
+ -\b-P\bP If set, the shell does not resolve symbolic links when
+ executing commands such as c\bcd\bd that change the current
working directory. It uses the physical directory
structure instead. By default, b\bba\bas\bsh\bh follows the logical
- chain of directories when performing commands which
+ chain of directories when performing commands which
change the current directory.
- -\b-T\bT If set, any traps on D\bDE\bEB\bBU\bUG\bG and R\bRE\bET\bTU\bUR\bRN\bN are inherited by
+ -\b-T\bT If set, any traps on D\bDE\bEB\bBU\bUG\bG and R\bRE\bET\bTU\bUR\bRN\bN are inherited by
shell functions, command substitutions, and commands ex-
- ecuted in a subshell environment. The D\bDE\bEB\bBU\bUG\bG and R\bRE\bET\bTU\bUR\bRN\bN
+ ecuted in a subshell environment. The D\bDE\bEB\bBU\bUG\bG and R\bRE\bET\bTU\bUR\bRN\bN
traps are normally not inherited in such cases.
-\b--\b- If no arguments follow this option, unset the positional
parameters. Otherwise, set the positional parameters to
the _\ba_\br_\bgs, even if some of them begin with a -\b-.
-\b- Signal the end of options, and assign all remaining _\ba_\br_\bgs
to the positional parameters. The -\b-x\bx and -\b-v\bv options are
- turned off. If there are no _\ba_\br_\bgs, the positional para-
+ turned off. If there are no _\ba_\br_\bgs, the positional para-
meters remain unchanged.
- The options are off by default unless otherwise noted. Using +
- rather than - causes these options to be turned off. The op-
+ The options are off by default unless otherwise noted. Using +
+ rather than - causes these options to be turned off. The op-
tions can also be specified as arguments to an invocation of the
- shell. The current set of options may be found in $\b$-\b-. The re-
- turn status is always zero unless an invalid option is encoun-
+ shell. The current set of options may be found in $\b$-\b-. The re-
+ turn status is always zero unless an invalid option is encoun-
tered.
s\bsh\bhi\bif\bft\bt [_\bn]
Rename positional parameters from _\bn+1 ... to $\b$1\b1 .\b..\b..\b..\b. Parameters
- represented by the numbers $\b$#\b# down to $\b$#\b#-_\bn+1 are unset. _\bn must
- be a non-negative number less than or equal to $\b$#\b#. If _\bn is 0,
- no parameters are changed. If _\bn is not given, it is assumed to
- be 1. If _\bn is greater than $\b$#\b#, the positional parameters are
- not changed. The return status is greater than zero if _\bn is
+ represented by the numbers $\b$#\b# down to $\b$#\b#-_\bn+1 are unset. _\bn must
+ be a non-negative number less than or equal to $\b$#\b#. If _\bn is 0,
+ no parameters are changed. If _\bn is not given, it is assumed to
+ be 1. If _\bn is greater than $\b$#\b#, the positional parameters are
+ not changed. The return status is greater than zero if _\bn is
greater than $\b$#\b# or less than zero; otherwise 0.
s\bsh\bho\bop\bpt\bt [-\b-p\bpq\bqs\bsu\bu] [-\b-o\bo] [_\bo_\bp_\bt_\bn_\ba_\bm_\be ...]
- Toggle the values of settings controlling optional shell behav-
- ior. The settings can be either those listed below, or, if the
+ Toggle the values of settings controlling optional shell behav-
+ ior. The settings can be either those listed below, or, if the
-\b-o\bo option is used, those available with the -\b-o\bo option to the s\bse\bet\bt
builtin command.
- With no options, or with the -\b-p\bp option, display a list of all
- settable options, with an indication of whether or not each is
- set; if any _\bo_\bp_\bt_\bn_\ba_\bm_\be_\bs are supplied, the output is restricted to
+ With no options, or with the -\b-p\bp option, display a list of all
+ settable options, with an indication of whether or not each is
+ set; if any _\bo_\bp_\bt_\bn_\ba_\bm_\be_\bs are supplied, the output is restricted to
those options. The -\b-p\bp option displays output in a form that may
be reused as input.
Other options have the following meanings:
-\b-s\bs Enable (set) each _\bo_\bp_\bt_\bn_\ba_\bm_\be.
-\b-u\bu Disable (unset) each _\bo_\bp_\bt_\bn_\ba_\bm_\be.
- -\b-q\bq Suppresses normal output (quiet mode); the return status
+ -\b-q\bq Suppresses normal output (quiet mode); the return status
indicates whether the _\bo_\bp_\bt_\bn_\ba_\bm_\be is set or unset. If multi-
- ple _\bo_\bp_\bt_\bn_\ba_\bm_\be arguments are supplied with -\b-q\bq, the return
+ ple _\bo_\bp_\bt_\bn_\ba_\bm_\be arguments are supplied with -\b-q\bq, the return
status is zero if all _\bo_\bp_\bt_\bn_\ba_\bm_\be_\bs are enabled; non-zero oth-
erwise.
- -\b-o\bo Restricts the values of _\bo_\bp_\bt_\bn_\ba_\bm_\be to be those defined for
+ -\b-o\bo Restricts the values of _\bo_\bp_\bt_\bn_\ba_\bm_\be to be those defined for
the -\b-o\bo option to the s\bse\bet\bt builtin.
- If either -\b-s\bs or -\b-u\bu is used with no _\bo_\bp_\bt_\bn_\ba_\bm_\be arguments, s\bsh\bho\bop\bpt\bt
- shows only those options which are set or unset, respectively.
- Unless otherwise noted, the s\bsh\bho\bop\bpt\bt options are disabled (unset)
+ If either -\b-s\bs or -\b-u\bu is used with no _\bo_\bp_\bt_\bn_\ba_\bm_\be arguments, s\bsh\bho\bop\bpt\bt
+ shows only those options which are set or unset, respectively.
+ Unless otherwise noted, the s\bsh\bho\bop\bpt\bt options are disabled (unset)
by default.
- The return status when listing options is zero if all _\bo_\bp_\bt_\bn_\ba_\bm_\be_\bs
- are enabled, non-zero otherwise. When setting or unsetting op-
- tions, the return status is zero unless an _\bo_\bp_\bt_\bn_\ba_\bm_\be is not a
+ The return status when listing options is zero if all _\bo_\bp_\bt_\bn_\ba_\bm_\be_\bs
+ are enabled, non-zero otherwise. When setting or unsetting op-
+ tions, the return status is zero unless an _\bo_\bp_\bt_\bn_\ba_\bm_\be is not a
valid shell option.
The list of s\bsh\bho\bop\bpt\bt options is:
a\bar\brr\bra\bay\by_\b_e\bex\bxp\bpa\ban\bnd\bd_\b_o\bon\bnc\bce\be
- If set, the shell suppresses multiple evaluation of as-
+ If set, the shell suppresses multiple evaluation of as-
sociative and indexed array subscripts during arithmetic
expression evaluation, while executing builtins that can
- perform variable assignments, and while executing
+ perform variable assignments, and while executing
builtins that perform array dereferencing.
a\bas\bss\bso\boc\bc_\b_e\bex\bxp\bpa\ban\bnd\bd_\b_o\bon\bnc\bce\be
Deprecated; a synonym for a\bar\brr\bra\bay\by_\b_e\bex\bxp\bpa\ban\bnd\bd_\b_o\bon\bnc\bce\be.
- a\bau\but\bto\boc\bcd\bd If set, a command name that is the name of a directory
- is executed as if it were the argument to the c\bcd\bd com-
+ a\bau\but\bto\boc\bcd\bd If set, a command name that is the name of a directory
+ is executed as if it were the argument to the c\bcd\bd com-
mand. This option is only used by interactive shells.
b\bba\bas\bsh\bh_\b_s\bso\bou\bur\brc\bce\be_\b_f\bfu\bul\bll\blp\bpa\bat\bth\bh
- If set, filenames added to the B\bBA\bAS\bSH\bH_\b_S\bSO\bOU\bUR\bRC\bCE\bE array vari-
- able are converted to full pathnames (see S\bSh\bhe\bel\bll\bl V\bVa\bar\bri\bi-\b-
+ If set, filenames added to the B\bBA\bAS\bSH\bH_\b_S\bSO\bOU\bUR\bRC\bCE\bE array vari-
+ able are converted to full pathnames (see S\bSh\bhe\bel\bll\bl V\bVa\bar\bri\bi-\b-
a\bab\bbl\ble\bes\bs above).
c\bcd\bda\bab\bbl\ble\be_\b_v\bva\bar\brs\bs
- If set, an argument to the c\bcd\bd builtin command that is
- not a directory is assumed to be the name of a variable
+ If set, an argument to the c\bcd\bd builtin command that is
+ not a directory is assumed to be the name of a variable
whose value is the directory to change to.
- c\bcd\bds\bsp\bpe\bel\bll\bl If set, the c\bcd\bd command attempts to correct minor errors
- in the spelling of a directory component. Minor errors
- include transposed characters, a missing character, and
+ c\bcd\bds\bsp\bpe\bel\bll\bl If set, the c\bcd\bd command attempts to correct minor errors
+ in the spelling of a directory component. Minor errors
+ include transposed characters, a missing character, and
one extra character. If c\bcd\bd corrects the directory name,
- it prints the corrected filename, and the command pro-
+ it prints the corrected filename, and the command pro-
ceeds. This option is only used by interactive shells.
c\bch\bhe\bec\bck\bkh\bha\bas\bsh\bh
If set, b\bba\bas\bsh\bh checks that a command found in the hash ta-
- ble exists before trying to execute it. If a hashed
- command no longer exists, b\bba\bas\bsh\bh performs a normal path
+ ble exists before trying to execute it. If a hashed
+ command no longer exists, b\bba\bas\bsh\bh performs a normal path
search.
c\bch\bhe\bec\bck\bkj\bjo\bob\bbs\bs
If set, b\bba\bas\bsh\bh lists the status of any stopped and running
- jobs before exiting an interactive shell. If any jobs
+ jobs before exiting an interactive shell. If any jobs
are running, b\bba\bas\bsh\bh defers the exit until a second exit is
- attempted without an intervening command (see J\bJO\bOB\bB C\bCO\bON\bN-\b-
- T\bTR\bRO\bOL\bL above). The shell always postpones exiting if any
+ attempted without an intervening command (see J\bJO\bOB\bB C\bCO\bON\bN-\b-
+ T\bTR\bRO\bOL\bL above). The shell always postpones exiting if any
jobs are stopped.
c\bch\bhe\bec\bck\bkw\bwi\bin\bns\bsi\biz\bze\be
- If set, b\bba\bas\bsh\bh checks the window size after each external
- (non-builtin) command and, if necessary, updates the
- values of L\bLI\bIN\bNE\bES\bS and C\bCO\bOL\bLU\bUM\bMN\bNS\bS, using the file descriptor
- associated with the standard error if it is a terminal.
+ If set, b\bba\bas\bsh\bh checks the window size after each external
+ (non-builtin) command and, if necessary, updates the
+ values of L\bLI\bIN\bNE\bES\bS and C\bCO\bOL\bLU\bUM\bMN\bNS\bS, using the file descriptor
+ associated with the standard error if it is a terminal.
This option is enabled by default.
- c\bcm\bmd\bdh\bhi\bis\bst\bt If set, b\bba\bas\bsh\bh attempts to save all lines of a multiple-
- line command in the same history entry. This allows
- easy re-editing of multi-line commands. This option is
- enabled by default, but only has an effect if command
+ c\bcm\bmd\bdh\bhi\bis\bst\bt If set, b\bba\bas\bsh\bh attempts to save all lines of a multiple-
+ line command in the same history entry. This allows
+ easy re-editing of multi-line commands. This option is
+ enabled by default, but only has an effect if command
history is enabled, as described above under H\bHI\bIS\bST\bTO\bOR\bRY\bY.
c\bco\bom\bmp\bpa\bat\bt3\b31\b1
c\bco\bom\bmp\bpa\bat\bt3\b32\b2
c\bco\bom\bmp\bpa\bat\bt4\b42\b2
c\bco\bom\bmp\bpa\bat\bt4\b43\b3
c\bco\bom\bmp\bpa\bat\bt4\b44\b4
- These control aspects of the shell's compatibility mode
+ These control aspects of the shell's compatibility mode
(see S\bSH\bHE\bEL\bLL\bL C\bCO\bOM\bMP\bPA\bAT\bTI\bIB\bBI\bIL\bLI\bIT\bTY\bY M\bMO\bOD\bDE\bE below).
c\bco\bom\bmp\bpl\ble\bet\bte\be_\b_f\bfu\bul\bll\blq\bqu\buo\bot\bte\be
- If set, b\bba\bas\bsh\bh quotes all shell metacharacters in file-
- names and directory names when performing completion.
+ If set, b\bba\bas\bsh\bh quotes all shell metacharacters in file-
+ names and directory names when performing completion.
If not set, b\bba\bas\bsh\bh removes metacharacters such as the dol-
- lar sign from the set of characters that will be quoted
- in completed filenames when these metacharacters appear
- in shell variable references in words to be completed.
- This means that dollar signs in variable names that ex-
- pand to directories will not be quoted; however, any
- dollar signs appearing in filenames will not be quoted,
- either. This is active only when bash is using back-
- slashes to quote completed filenames. This variable is
- set by default, which is the default bash behavior in
+ lar sign from the set of characters that will be quoted
+ in completed filenames when these metacharacters appear
+ in shell variable references in words to be completed.
+ This means that dollar signs in variable names that ex-
+ pand to directories will not be quoted; however, any
+ dollar signs appearing in filenames will not be quoted,
+ either. This is active only when bash is using back-
+ slashes to quote completed filenames. This variable is
+ set by default, which is the default bash behavior in
versions through 4.2.
d\bdi\bir\bre\bex\bxp\bpa\ban\bnd\bd
- If set, b\bba\bas\bsh\bh replaces directory names with the results
- of word expansion when performing filename completion.
+ If set, b\bba\bas\bsh\bh replaces directory names with the results
+ of word expansion when performing filename completion.
This changes the contents of the r\bre\bea\bad\bdl\bli\bin\bne\be editing
- buffer. If not set, b\bba\bas\bsh\bh attempts to preserve what the
+ buffer. If not set, b\bba\bas\bsh\bh attempts to preserve what the
user typed.
d\bdi\bir\brs\bsp\bpe\bel\bll\bl
- If set, b\bba\bas\bsh\bh attempts spelling correction on directory
- names during word completion if the directory name ini-
+ If set, b\bba\bas\bsh\bh attempts spelling correction on directory
+ names during word completion if the directory name ini-
tially supplied does not exist.
- d\bdo\bot\btg\bgl\blo\bob\bb If set, b\bba\bas\bsh\bh includes filenames beginning with a "." in
- the results of pathname expansion. The filenames _\b. and
+ d\bdo\bot\btg\bgl\blo\bob\bb If set, b\bba\bas\bsh\bh includes filenames beginning with a "." in
+ the results of pathname expansion. The filenames _\b. and
_\b._\b. must always be matched explicitly, even if d\bdo\bot\btg\bgl\blo\bob\bb is
set.
e\bex\bxe\bec\bcf\bfa\bai\bil\bl
If set, a non-interactive shell will not exit if it can-
- not execute the file specified as an argument to the
- e\bex\bxe\bec\bc builtin. An interactive shell does not exit if
+ not execute the file specified as an argument to the
+ e\bex\bxe\bec\bc builtin. An interactive shell does not exit if
e\bex\bxe\bec\bc fails.
e\bex\bxp\bpa\ban\bnd\bd_\b_a\bal\bli\bia\bas\bse\bes\bs
- If set, aliases are expanded as described above under
+ If set, aliases are expanded as described above under
A\bAL\bLI\bIA\bAS\bSE\bES\bS. This option is enabled by default for interac-
tive shells.
e\bex\bxt\btd\bde\beb\bbu\bug\bg
- If set at shell invocation, or in a shell startup file,
+ If set at shell invocation, or in a shell startup file,
arrange to execute the debugger profile before the shell
- starts, identical to the -\b--\b-d\bde\beb\bbu\bug\bgg\bge\ber\br option. If set af-
- ter invocation, behavior intended for use by debuggers
+ starts, identical to the -\b--\b-d\bde\beb\bbu\bug\bgg\bge\ber\br option. If set af-
+ ter invocation, behavior intended for use by debuggers
is enabled:
1\b1.\b. The -\b-F\bF option to the d\bde\bec\bcl\bla\bar\bre\be builtin displays the
source file name and line number corresponding to
each function name supplied as an argument.
- 2\b2.\b. If the command run by the D\bDE\bEB\bBU\bUG\bG trap returns a
- non-zero value, the next command is skipped and
+ 2\b2.\b. If the command run by the D\bDE\bEB\bBU\bUG\bG trap returns a
+ non-zero value, the next command is skipped and
not executed.
- 3\b3.\b. If the command run by the D\bDE\bEB\bBU\bUG\bG trap returns a
- value of 2, and the shell is executing in a sub-
- routine (a shell function or a shell script exe-
- cuted by the .\b. or s\bso\bou\bur\brc\bce\be builtins), the shell
+ 3\b3.\b. If the command run by the D\bDE\bEB\bBU\bUG\bG trap returns a
+ value of 2, and the shell is executing in a sub-
+ routine (a shell function or a shell script exe-
+ cuted by the .\b. or s\bso\bou\bur\brc\bce\be builtins), the shell
simulates a call to r\bre\bet\btu\bur\brn\bn.
- 4\b4.\b. B\bBA\bAS\bSH\bH_\b_A\bAR\bRG\bGC\bC and B\bBA\bAS\bSH\bH_\b_A\bAR\bRG\bGV\bV are updated as described
+ 4\b4.\b. B\bBA\bAS\bSH\bH_\b_A\bAR\bRG\bGC\bC and B\bBA\bAS\bSH\bH_\b_A\bAR\bRG\bGV\bV are updated as described
in their descriptions above).
- 5\b5.\b. Function tracing is enabled: command substitu-
+ 5\b5.\b. Function tracing is enabled: command substitu-
tion, shell functions, and subshells invoked with
(\b( _\bc_\bo_\bm_\bm_\ba_\bn_\bd )\b) inherit the D\bDE\bEB\bBU\bUG\bG and R\bRE\bET\bTU\bUR\bRN\bN traps.
- 6\b6.\b. Error tracing is enabled: command substitution,
- shell functions, and subshells invoked with (\b(
+ 6\b6.\b. Error tracing is enabled: command substitution,
+ shell functions, and subshells invoked with (\b(
_\bc_\bo_\bm_\bm_\ba_\bn_\bd )\b) inherit the E\bER\bRR\bR trap.
- e\bex\bxt\btg\bgl\blo\bob\bb If set, enable the extended pattern matching features
+ e\bex\bxt\btg\bgl\blo\bob\bb If set, enable the extended pattern matching features
described above under P\bPa\bat\bth\bhn\bna\bam\bme\be E\bEx\bxp\bpa\ban\bns\bsi\bio\bon\bn.
e\bex\bxt\btq\bqu\buo\bot\bte\be
- If set, $\b$'_\bs_\bt_\br_\bi_\bn_\bg' and $\b$"_\bs_\bt_\br_\bi_\bn_\bg" quoting is performed
- within $\b${\b{_\bp_\ba_\br_\ba_\bm_\be_\bt_\be_\br}\b} expansions enclosed in double
+ If set, $\b$'_\bs_\bt_\br_\bi_\bn_\bg' and $\b$"_\bs_\bt_\br_\bi_\bn_\bg" quoting is performed
+ within $\b${\b{_\bp_\ba_\br_\ba_\bm_\be_\bt_\be_\br}\b} expansions enclosed in double
quotes. This option is enabled by default.
f\bfa\bai\bil\blg\bgl\blo\bob\bb
- If set, patterns which fail to match filenames during
+ If set, patterns which fail to match filenames during
pathname expansion result in an expansion error.
f\bfo\bor\brc\bce\be_\b_f\bfi\big\bgn\bno\bor\bre\be
- If set, the suffixes specified by the F\bFI\bIG\bGN\bNO\bOR\bRE\bE shell
- variable cause words to be ignored when performing word
+ If set, the suffixes specified by the F\bFI\bIG\bGN\bNO\bOR\bRE\bE shell
+ variable cause words to be ignored when performing word
completion even if the ignored words are the only possi-
- ble completions. See S\bSh\bhe\bel\bll\bl V\bVa\bar\bri\bia\bab\bbl\ble\bes\bs above for a de-
- scription of F\bFI\bIG\bGN\bNO\bOR\bRE\bE. This option is enabled by de-
+ ble completions. See S\bSh\bhe\bel\bll\bl V\bVa\bar\bri\bia\bab\bbl\ble\bes\bs above for a de-
+ scription of F\bFI\bIG\bGN\bNO\bOR\bRE\bE. This option is enabled by de-
fault.
g\bgl\blo\bob\bba\bas\bsc\bci\bii\bir\bra\ban\bng\bge\bes\bs
- If set, range expressions used in pattern matching
- bracket expressions (see P\bPa\bat\btt\bte\ber\brn\bn M\bMa\bat\btc\bch\bhi\bin\bng\bg above) behave
- as if in the traditional C locale when performing com-
- parisons. That is, pattern matching does not take the
- current locale's collating sequence into account, so b\bb
- will not collate between A\bA and B\bB, and upper-case and
+ If set, range expressions used in pattern matching
+ bracket expressions (see P\bPa\bat\btt\bte\ber\brn\bn M\bMa\bat\btc\bch\bhi\bin\bng\bg above) behave
+ as if in the traditional C locale when performing com-
+ parisons. That is, pattern matching does not take the
+ current locale's collating sequence into account, so b\bb
+ will not collate between A\bA and B\bB, and upper-case and
lower-case ASCII characters will collate together.
g\bgl\blo\bob\bbs\bsk\bki\bip\bpd\bdo\bot\bts\bs
- If set, pathname expansion will never match the file-
- names _\b. and _\b._\b., even if the pattern begins with a ".".
+ If set, pathname expansion will never match the file-
+ names _\b. and _\b._\b., even if the pattern begins with a ".".
This option is enabled by default.
g\bgl\blo\bob\bbs\bst\bta\bar\br
If set, the pattern *\b**\b* used in a pathname expansion con-
- text will match all files and zero or more directories
- and subdirectories. If the pattern is followed by a /\b/,
+ text will match all files and zero or more directories
+ and subdirectories. If the pattern is followed by a /\b/,
only directories and subdirectories match.
g\bgn\bnu\bu_\b_e\ber\brr\brf\bfm\bmt\bt
If set, shell error messages are written in the standard
GNU error message format.
h\bhi\bis\bst\bta\bap\bpp\bpe\ben\bnd\bd
- If set, the history list is appended to the file named
+ If set, the history list is appended to the file named
by the value of the H\bHI\bIS\bST\bTF\bFI\bIL\bLE\bE variable when the shell ex-
its, rather than overwriting the file.
h\bhi\bis\bst\btr\bre\bee\bed\bdi\bit\bt
- If set, and r\bre\bea\bad\bdl\bli\bin\bne\be is being used, the user is given
- the opportunity to re-edit a failed history substitu-
+ If set, and r\bre\bea\bad\bdl\bli\bin\bne\be is being used, the user is given
+ the opportunity to re-edit a failed history substitu-
tion.
h\bhi\bis\bst\btv\bve\ber\bri\bif\bfy\by
- If set, and r\bre\bea\bad\bdl\bli\bin\bne\be is being used, the results of his-
- tory substitution are not immediately passed to the
- shell parser. Instead, the resulting line is loaded
+ If set, and r\bre\bea\bad\bdl\bli\bin\bne\be is being used, the results of his-
+ tory substitution are not immediately passed to the
+ shell parser. Instead, the resulting line is loaded
into the r\bre\bea\bad\bdl\bli\bin\bne\be editing buffer, allowing further modi-
fication.
h\bho\bos\bst\btc\bco\bom\bmp\bpl\ble\bet\bte\be
If set, and r\bre\bea\bad\bdl\bli\bin\bne\be is being used, b\bba\bas\bsh\bh will attempt to
- perform hostname completion when a word containing a @\b@
- is being completed (see C\bCo\bom\bmp\bpl\ble\bet\bti\bin\bng\bg under R\bRE\bEA\bAD\bDL\bLI\bIN\bNE\bE
+ perform hostname completion when a word containing a @\b@
+ is being completed (see C\bCo\bom\bmp\bpl\ble\bet\bti\bin\bng\bg under R\bRE\bEA\bAD\bDL\bLI\bIN\bNE\bE
above). This is enabled by default.
h\bhu\bup\bpo\bon\bne\bex\bxi\bit\bt
If set, b\bba\bas\bsh\bh will send S\bSI\bIG\bGH\bHU\bUP\bP to all jobs when an inter-
active login shell exits.
i\bin\bnh\bhe\ber\bri\bit\bt_\b_e\ber\brr\bre\bex\bxi\bit\bt
- If set, command substitution inherits the value of the
- e\ber\brr\bre\bex\bxi\bit\bt option, instead of unsetting it in the subshell
- environment. This option is enabled when posix mode is
+ If set, command substitution inherits the value of the
+ e\ber\brr\bre\bex\bxi\bit\bt option, instead of unsetting it in the subshell
+ environment. This option is enabled when posix mode is
enabled.
i\bin\bnt\bte\ber\bra\bac\bct\bti\biv\bve\be_\b_c\bco\bom\bmm\bme\ben\bnt\bts\bs
- In an interactive shell, a word beginning with #\b# causes
- that word and all remaining characters on that line to
- be ignored, as in a non-interactive shell (see C\bCO\bOM\bMM\bME\bEN\bNT\bTS\bS
+ In an interactive shell, a word beginning with #\b# causes
+ that word and all remaining characters on that line to
+ be ignored, as in a non-interactive shell (see C\bCO\bOM\bMM\bME\bEN\bNT\bTS\bS
above). This option is enabled by default.
l\bla\bas\bst\btp\bpi\bip\bpe\be
- If set, and job control is not active, the shell runs
+ If set, and job control is not active, the shell runs
the last command of a pipeline not executed in the back-
ground in the current shell environment.
- l\bli\bit\bth\bhi\bis\bst\bt If set, and the c\bcm\bmd\bdh\bhi\bis\bst\bt option is enabled, multi-line
+ l\bli\bit\bth\bhi\bis\bst\bt If set, and the c\bcm\bmd\bdh\bhi\bis\bst\bt option is enabled, multi-line
commands are saved to the history with embedded newlines
rather than using semicolon separators where possible.
l\blo\boc\bca\bal\blv\bva\bar\br_\b_i\bin\bnh\bhe\ber\bri\bit\bt
scope before any new value is assigned. The nameref at-
tribute is not inherited.
l\blo\boc\bca\bal\blv\bva\bar\br_\b_u\bun\bns\bse\bet\bt
- If set, calling u\bun\bns\bse\bet\bt on local variables in previous
- function scopes marks them so subsequent lookups find
+ If set, calling u\bun\bns\bse\bet\bt on local variables in previous
+ function scopes marks them so subsequent lookups find
them unset until that function returns. This is identi-
- cal to the behavior of unsetting local variables at the
+ cal to the behavior of unsetting local variables at the
current function scope.
l\blo\bog\bgi\bin\bn_\b_s\bsh\bhe\bel\bll\bl
- The shell sets this option if it is started as a login
- shell (see I\bIN\bNV\bVO\bOC\bCA\bAT\bTI\bIO\bON\bN above). The value may not be
+ The shell sets this option if it is started as a login
+ shell (see I\bIN\bNV\bVO\bOC\bCA\bAT\bTI\bIO\bON\bN above). The value may not be
changed.
m\bma\bai\bil\blw\bwa\bar\brn\bn
- If set, and a file that b\bba\bas\bsh\bh is checking for mail has
- been accessed since the last time it was checked, b\bba\bas\bsh\bh
- displays the message "The mail in _\bm_\ba_\bi_\bl_\bf_\bi_\bl_\be has been
+ If set, and a file that b\bba\bas\bsh\bh is checking for mail has
+ been accessed since the last time it was checked, b\bba\bas\bsh\bh
+ displays the message "The mail in _\bm_\ba_\bi_\bl_\bf_\bi_\bl_\be has been
read".
n\bno\bo_\b_e\bem\bmp\bpt\bty\by_\b_c\bcm\bmd\bd_\b_c\bco\bom\bmp\bpl\ble\bet\bti\bio\bon\bn
If set, and r\bre\bea\bad\bdl\bli\bin\bne\be is being used, b\bba\bas\bsh\bh does not search
- P\bPA\bAT\bTH\bH for possible completions when completion is at-
+ P\bPA\bAT\bTH\bH for possible completions when completion is at-
tempted on an empty line.
n\bno\boc\bca\bas\bse\beg\bgl\blo\bob\bb
- If set, b\bba\bas\bsh\bh matches filenames in a case-insensitive
+ If set, b\bba\bas\bsh\bh matches filenames in a case-insensitive
fashion when performing pathname expansion (see P\bPa\bat\bth\bhn\bna\bam\bme\be
E\bEx\bxp\bpa\ban\bns\bsi\bio\bon\bn above).
n\bno\boc\bca\bas\bse\bem\bma\bat\btc\bch\bh
- If set, b\bba\bas\bsh\bh matches patterns in a case-insensitive
+ If set, b\bba\bas\bsh\bh matches patterns in a case-insensitive
fashion when performing matching while executing c\bca\bas\bse\be or
[\b[[\b[ conditional commands, when performing pattern substi-
- tution word expansions, or when filtering possible com-
+ tution word expansions, or when filtering possible com-
pletions as part of programmable completion.
n\bno\boe\bex\bxp\bpa\ban\bnd\bd_\b_t\btr\bra\ban\bns\bsl\bla\bat\bti\bio\bon\bn
- If set, b\bba\bas\bsh\bh encloses the translated results of $\b$"\b"..."\b"
- quoting in single quotes instead of double quotes. If
+ If set, b\bba\bas\bsh\bh encloses the translated results of $\b$"\b"..."\b"
+ quoting in single quotes instead of double quotes. If
the string is not translated, this has no effect.
n\bnu\bul\bll\blg\bgl\blo\bob\bb
If set, pathname expansion patterns which match no files
removed, rather than expanding to themselves.
p\bpa\bat\bts\bsu\bub\bb_\b_r\bre\bep\bpl\bla\bac\bce\bem\bme\ben\bnt\bt
If set, b\bba\bas\bsh\bh expands occurrences of &\b& in the replacement
- string of pattern substitution to the text matched by
- the pattern, as described under P\bPa\bar\bra\bam\bme\bet\bte\ber\br E\bEx\bxp\bpa\ban\bns\bsi\bio\bon\bn
+ string of pattern substitution to the text matched by
+ the pattern, as described under P\bPa\bar\bra\bam\bme\bet\bte\ber\br E\bEx\bxp\bpa\ban\bns\bsi\bio\bon\bn
above. This option is enabled by default.
p\bpr\bro\bog\bgc\bco\bom\bmp\bp
- If set, enable the programmable completion facilities
+ If set, enable the programmable completion facilities
(see P\bPr\bro\bog\bgr\bra\bam\bmm\bma\bab\bbl\ble\be C\bCo\bom\bmp\bpl\ble\bet\bti\bio\bon\bn above). This option is en-
abled by default.
p\bpr\bro\bog\bgc\bco\bom\bmp\bp_\b_a\bal\bli\bia\bas\bs
- If set, and programmable completion is enabled, b\bba\bas\bsh\bh
- treats a command name that doesn't have any completions
+ If set, and programmable completion is enabled, b\bba\bas\bsh\bh
+ treats a command name that doesn't have any completions
as a possible alias and attempts alias expansion. If it
- has an alias, b\bba\bas\bsh\bh attempts programmable completion us-
+ has an alias, b\bba\bas\bsh\bh attempts programmable completion us-
ing the command word resulting from the expanded alias.
p\bpr\bro\bom\bmp\bpt\btv\bva\bar\brs\bs
If set, prompt strings undergo parameter expansion, com-
- mand substitution, arithmetic expansion, and quote re-
- moval after being expanded as described in P\bPR\bRO\bOM\bMP\bPT\bTI\bIN\bNG\bG
+ mand substitution, arithmetic expansion, and quote re-
+ moval after being expanded as described in P\bPR\bRO\bOM\bMP\bPT\bTI\bIN\bNG\bG
above. This option is enabled by default.
r\bre\bes\bst\btr\bri\bic\bct\bte\bed\bd_\b_s\bsh\bhe\bel\bll\bl
- The shell sets this option if it is started in re-
- stricted mode (see R\bRE\bES\bST\bTR\bRI\bIC\bCT\bTE\bED\bD S\bSH\bHE\bEL\bLL\bL below). The value
- may not be changed. This is not reset when the startup
- files are executed, allowing the startup files to dis-
+ The shell sets this option if it is started in re-
+ stricted mode (see R\bRE\bES\bST\bTR\bRI\bIC\bCT\bTE\bED\bD S\bSH\bHE\bEL\bLL\bL below). The value
+ may not be changed. This is not reset when the startup
+ files are executed, allowing the startup files to dis-
cover whether or not a shell is restricted.
s\bsh\bhi\bif\bft\bt_\b_v\bve\ber\brb\bbo\bos\bse\be
- If set, the s\bsh\bhi\bif\bft\bt builtin prints an error message when
+ If set, the s\bsh\bhi\bif\bft\bt builtin prints an error message when
the shift count exceeds the number of positional parame-
ters.
s\bso\bou\bur\brc\bce\bep\bpa\bat\bth\bh
If set, the .\b. (s\bso\bou\bur\brc\bce\be) builtin uses the value of P\bPA\bAT\bTH\bH to
- find the directory containing the file supplied as an
- argument when the -\b-p\bp option is not supplied. This op-
+ find the directory containing the file supplied as an
+ argument when the -\b-p\bp option is not supplied. This op-
tion is enabled by default.
v\bva\bar\brr\bre\bed\bdi\bir\br_\b_c\bcl\blo\bos\bse\be
- If set, the shell automatically closes file descriptors
- assigned using the _\b{_\bv_\ba_\br_\bn_\ba_\bm_\be_\b} redirection syntax (see
+ If set, the shell automatically closes file descriptors
+ assigned using the _\b{_\bv_\ba_\br_\bn_\ba_\bm_\be_\b} redirection syntax (see
R\bRE\bED\bDI\bIR\bRE\bEC\bCT\bTI\bIO\bON\bN above) instead of leaving them open when the
command completes.
x\bxp\bpg\bg_\b_e\bec\bch\bho\bo
- If set, the e\bec\bch\bho\bo builtin expands backslash-escape se-
- quences by default. If the p\bpo\bos\bsi\bix\bx shell option is also
+ If set, the e\bec\bch\bho\bo builtin expands backslash-escape se-
+ quences by default. If the p\bpo\bos\bsi\bix\bx shell option is also
enabled, e\bec\bch\bho\bo does not interpret any options.
s\bsu\bus\bsp\bpe\ben\bnd\bd [-\b-f\bf]
- Suspend the execution of this shell until it receives a S\bSI\bIG\bGC\bCO\bON\bNT\bT
- signal. A login shell, or a shell without job control enabled,
- cannot be suspended; the -\b-f\bf option will override this and force
- the suspension. The return status is 0 unless the shell is a
- login shell or job control is not enabled and -\b-f\bf is not sup-
+ Suspend the execution of this shell until it receives a S\bSI\bIG\bGC\bCO\bON\bNT\bT
+ signal. A login shell, or a shell without job control enabled,
+ cannot be suspended; the -\b-f\bf option will override this and force
+ the suspension. The return status is 0 unless the shell is a
+ login shell or job control is not enabled and -\b-f\bf is not sup-
plied.
t\bte\bes\bst\bt _\be_\bx_\bp_\br
[\b[ _\be_\bx_\bp_\br ]\b]
Return a status of 0 (true) or 1 (false) depending on the evalu-
- ation of the conditional expression _\be_\bx_\bp_\br. Each operator and
- operand must be a separate argument. Expressions are composed
- of the primaries described above under C\bCO\bON\bND\bDI\bIT\bTI\bIO\bON\bNA\bAL\bL E\bEX\bXP\bPR\bRE\bES\bSS\bSI\bIO\bON\bNS\bS.
- t\bte\bes\bst\bt does not accept any options, nor does it accept and ignore
+ ation of the conditional expression _\be_\bx_\bp_\br. Each operator and
+ operand must be a separate argument. Expressions are composed
+ of the primaries described above under C\bCO\bON\bND\bDI\bIT\bTI\bIO\bON\bNA\bAL\bL E\bEX\bXP\bPR\bRE\bES\bSS\bSI\bIO\bON\bNS\bS.
+ t\bte\bes\bst\bt does not accept any options, nor does it accept and ignore
an argument of -\b--\b- as signifying the end of options.
- Expressions may be combined using the following operators,
- listed in decreasing order of precedence. The evaluation de-
+ Expressions may be combined using the following operators,
+ listed in decreasing order of precedence. The evaluation de-
pends on the number of arguments; see below. t\bte\bes\bst\bt uses operator
precedence when there are five or more arguments.
!\b! _\be_\bx_\bp_\br True if _\be_\bx_\bp_\br is false.
(\b( _\be_\bx_\bp_\br )\b)
- Returns the value of _\be_\bx_\bp_\br. This may be used to override
+ Returns the value of _\be_\bx_\bp_\br. This may be used to override
normal operator precedence.
_\be_\bx_\bp_\br_\b1 -a\ba _\be_\bx_\bp_\br_\b2
True if both _\be_\bx_\bp_\br_\b1 and _\be_\bx_\bp_\br_\b2 are true.
null.
2 arguments
If the first argument is !\b!, the expression is true if and
- only if the second argument is null. If the first argu-
- ment is one of the unary conditional operators listed
- above under C\bCO\bON\bND\bDI\bIT\bTI\bIO\bON\bNA\bAL\bL E\bEX\bXP\bPR\bRE\bES\bSS\bSI\bIO\bON\bNS\bS, the expression is
+ only if the second argument is null. If the first argu-
+ ment is one of the unary conditional operators listed
+ above under C\bCO\bON\bND\bDI\bIT\bTI\bIO\bON\bNA\bAL\bL E\bEX\bXP\bPR\bRE\bES\bSS\bSI\bIO\bON\bNS\bS, the expression is
true if the unary test is true. If the first argument is
not a valid unary conditional operator, the expression is
false.
3 arguments
The following conditions are applied in the order listed.
- If the second argument is one of the binary conditional
+ If the second argument is one of the binary conditional
operators listed above under C\bCO\bON\bND\bDI\bIT\bTI\bIO\bON\bNA\bAL\bL E\bEX\bXP\bPR\bRE\bES\bSS\bSI\bIO\bON\bNS\bS, the
result of the expression is the result of the binary test
- using the first and third arguments as operands. The -\b-a\ba
- and -\b-o\bo operators are considered binary operators when
- there are three arguments. If the first argument is !\b!,
- the value is the negation of the two-argument test using
+ using the first and third arguments as operands. The -\b-a\ba
+ and -\b-o\bo operators are considered binary operators when
+ there are three arguments. If the first argument is !\b!,
+ the value is the negation of the two-argument test using
the second and third arguments. If the first argument is
exactly (\b( and the third argument is exactly )\b), the result
- is the one-argument test of the second argument. Other-
+ is the one-argument test of the second argument. Other-
wise, the expression is false.
4 arguments
The following conditions are applied in the order listed.
If the first argument is !\b!, the result is the negation of
- the three-argument expression composed of the remaining
- arguments. If the first argument is exactly (\b( and the
+ the three-argument expression composed of the remaining
+ arguments. If the first argument is exactly (\b( and the
fourth argument is exactly )\b), the result is the two-argu-
- ment test of the second and third arguments. Otherwise,
- the expression is parsed and evaluated according to
+ ment test of the second and third arguments. Otherwise,
+ the expression is parsed and evaluated according to
precedence using the rules listed above.
5 or more arguments
- The expression is parsed and evaluated according to
+ The expression is parsed and evaluated according to
precedence using the rules listed above.
When the shell is in posix mode, or if the expression is part of
the [\b[[\b[ command, the <\b< and >\b> operators sort using the current lo-
- cale. If the shell is not in posix mode, the t\bte\bes\bst\bt and [\b[ com-
+ cale. If the shell is not in posix mode, the t\bte\bes\bst\bt and [\b[ com-
mands sort lexicographically using ASCII ordering.
- The historical operator-precedence parsing with 4 or more argu-
- ments can lead to ambiguities when it encounters strings that
- look like primaries. The POSIX standard has deprecated the -\b-a\ba
- and -\b-o\bo primaries and enclosing expressions within parentheses.
- Scripts should no longer use them. It's much more reliable to
- restrict test invocations to a single primary, and to replace
+ The historical operator-precedence parsing with 4 or more argu-
+ ments can lead to ambiguities when it encounters strings that
+ look like primaries. The POSIX standard has deprecated the -\b-a\ba
+ and -\b-o\bo primaries and enclosing expressions within parentheses.
+ Scripts should no longer use them. It's much more reliable to
+ restrict test invocations to a single primary, and to replace
uses of -\b-a\ba and -\b-o\bo with the shell's &\b&&\b& and |\b||\b| list operators.
- t\bti\bim\bme\bes\bs Print the accumulated user and system times for the shell and
+ t\bti\bim\bme\bes\bs Print the accumulated user and system times for the shell and
for processes run from the shell. The return status is 0.
t\btr\bra\bap\bp [-\b-l\blp\bpP\bP] [[_\ba_\bc_\bt_\bi_\bo_\bn] _\bs_\bi_\bg_\bs_\bp_\be_\bc ...]
The _\ba_\bc_\bt_\bi_\bo_\bn is a command that is read and executed when the shell
- receives any of the signals _\bs_\bi_\bg_\bs_\bp_\be_\bc. If _\ba_\bc_\bt_\bi_\bo_\bn is absent (and
+ receives any of the signals _\bs_\bi_\bg_\bs_\bp_\be_\bc. If _\ba_\bc_\bt_\bi_\bo_\bn is absent (and
there is a single _\bs_\bi_\bg_\bs_\bp_\be_\bc) or -\b-, each specified _\bs_\bi_\bg_\bs_\bp_\be_\bc is reset
- to the value it had when the shell was started. If _\ba_\bc_\bt_\bi_\bo_\bn is
- the null string the signal specified by each _\bs_\bi_\bg_\bs_\bp_\be_\bc is ignored
+ to the value it had when the shell was started. If _\ba_\bc_\bt_\bi_\bo_\bn is
+ the null string the signal specified by each _\bs_\bi_\bg_\bs_\bp_\be_\bc is ignored
by the shell and by the commands it invokes.
- If no arguments are supplied, t\btr\bra\bap\bp displays the actions associ-
+ If no arguments are supplied, t\btr\bra\bap\bp displays the actions associ-
ated with each trapped signal as a set of t\btr\bra\bap\bp commands that can
- be reused as shell input to restore the current signal disposi-
- tions. If -\b-p\bp is given, and _\ba_\bc_\bt_\bi_\bo_\bn is not present, then t\btr\bra\bap\bp
- displays the actions associated with each _\bs_\bi_\bg_\bs_\bp_\be_\bc or, if none
+ be reused as shell input to restore the current signal disposi-
+ tions. If -\b-p\bp is given, and _\ba_\bc_\bt_\bi_\bo_\bn is not present, then t\btr\bra\bap\bp
+ displays the actions associated with each _\bs_\bi_\bg_\bs_\bp_\be_\bc or, if none
are supplied, for all trapped signals, as a set of t\btr\bra\bap\bp commands
- that can be reused as shell input to restore the current signal
- dispositions. The -\b-P\bP option behaves similarly, but displays
- only the actions associated with each _\bs_\bi_\bg_\bs_\bp_\be_\bc argument. -\b-P\bP re-
- quires at least one _\bs_\bi_\bg_\bs_\bp_\be_\bc argument. The -\b-P\bP or -\b-p\bp options may
- be used in a subshell environment (e.g., command substitution)
- and, as long as they are used before t\btr\bra\bap\bp is used to change a
+ that can be reused as shell input to restore the current signal
+ dispositions. The -\b-P\bP option behaves similarly, but displays
+ only the actions associated with each _\bs_\bi_\bg_\bs_\bp_\be_\bc argument. -\b-P\bP re-
+ quires at least one _\bs_\bi_\bg_\bs_\bp_\be_\bc argument. The -\b-P\bP or -\b-p\bp options may
+ be used in a subshell environment (e.g., command substitution)
+ and, as long as they are used before t\btr\bra\bap\bp is used to change a
signal's handling, will display the state of its parent's traps.
- The -\b-l\bl option prints a list of signal names and their corre-
- sponding numbers. Each _\bs_\bi_\bg_\bs_\bp_\be_\bc is either a signal name defined
+ The -\b-l\bl option prints a list of signal names and their corre-
+ sponding numbers. Each _\bs_\bi_\bg_\bs_\bp_\be_\bc is either a signal name defined
in <_\bs_\bi_\bg_\bn_\ba_\bl_\b._\bh>, or a signal number. Signal names are case insen-
- sitive and the S\bSI\bIG\bG prefix is optional. If -\b-l\bl is supplied with
+ sitive and the S\bSI\bIG\bG prefix is optional. If -\b-l\bl is supplied with
no _\bs_\bi_\bg_\bs_\bp_\be_\bc arguments, it prints a list of valid signal names.
- If a _\bs_\bi_\bg_\bs_\bp_\be_\bc is E\bEX\bXI\bIT\bT (0), _\ba_\bc_\bt_\bi_\bo_\bn is executed on exit from the
- shell. If a _\bs_\bi_\bg_\bs_\bp_\be_\bc is D\bDE\bEB\bBU\bUG\bG, _\ba_\bc_\bt_\bi_\bo_\bn is executed before every
- _\bs_\bi_\bm_\bp_\bl_\be _\bc_\bo_\bm_\bm_\ba_\bn_\bd, _\bf_\bo_\br command, _\bc_\ba_\bs_\be command, _\bs_\be_\bl_\be_\bc_\bt command, ((
- arithmetic command, [[ conditional command, arithmetic _\bf_\bo_\br com-
- mand, and before the first command executes in a shell function
- (see S\bSH\bHE\bEL\bLL\bL G\bGR\bRA\bAM\bMM\bMA\bAR\bR above). Refer to the description of the
- e\bex\bxt\btd\bde\beb\bbu\bug\bg shell option (see s\bsh\bho\bop\bpt\bt above) for details of its ef-
- fect on the D\bDE\bEB\bBU\bUG\bG trap. If a _\bs_\bi_\bg_\bs_\bp_\be_\bc is R\bRE\bET\bTU\bUR\bRN\bN, _\ba_\bc_\bt_\bi_\bo_\bn is exe-
+ If a _\bs_\bi_\bg_\bs_\bp_\be_\bc is E\bEX\bXI\bIT\bT (0), _\ba_\bc_\bt_\bi_\bo_\bn is executed on exit from the
+ shell. If a _\bs_\bi_\bg_\bs_\bp_\be_\bc is D\bDE\bEB\bBU\bUG\bG, _\ba_\bc_\bt_\bi_\bo_\bn is executed before every
+ _\bs_\bi_\bm_\bp_\bl_\be _\bc_\bo_\bm_\bm_\ba_\bn_\bd, _\bf_\bo_\br command, _\bc_\ba_\bs_\be command, _\bs_\be_\bl_\be_\bc_\bt command, ((
+ arithmetic command, [[ conditional command, arithmetic _\bf_\bo_\br com-
+ mand, and before the first command executes in a shell function
+ (see S\bSH\bHE\bEL\bLL\bL G\bGR\bRA\bAM\bMM\bMA\bAR\bR above). Refer to the description of the
+ e\bex\bxt\btd\bde\beb\bbu\bug\bg shell option (see s\bsh\bho\bop\bpt\bt above) for details of its ef-
+ fect on the D\bDE\bEB\bBU\bUG\bG trap. If a _\bs_\bi_\bg_\bs_\bp_\be_\bc is R\bRE\bET\bTU\bUR\bRN\bN, _\ba_\bc_\bt_\bi_\bo_\bn is exe-
cuted each time a shell function or a script executed with the .\b.
or s\bso\bou\bur\brc\bce\be builtins finishes executing.
- If a _\bs_\bi_\bg_\bs_\bp_\be_\bc is E\bER\bRR\bR, _\ba_\bc_\bt_\bi_\bo_\bn is executed whenever a pipeline
- (which may consist of a single simple command), a list, or a
- compound command returns a non-zero exit status, subject to the
- following conditions. The E\bER\bRR\bR trap is not executed if the
+ If a _\bs_\bi_\bg_\bs_\bp_\be_\bc is E\bER\bRR\bR, _\ba_\bc_\bt_\bi_\bo_\bn is executed whenever a pipeline
+ (which may consist of a single simple command), a list, or a
+ compound command returns a non-zero exit status, subject to the
+ following conditions. The E\bER\bRR\bR trap is not executed if the
failed command is part of the command list immediately following
a w\bwh\bhi\bil\ble\be or u\bun\bnt\bti\bil\bl reserved word, part of the test in an _\bi_\bf state-
- ment, part of a command executed in a &\b&&\b& or |\b||\b| list except the
- command following the final &\b&&\b& or |\b||\b|, any command in a pipeline
- but the last (subject to the state of the p\bpi\bip\bpe\bef\bfa\bai\bil\bl shell op-
- tion), or if the command's return value is being inverted using
+ ment, part of a command executed in a &\b&&\b& or |\b||\b| list except the
+ command following the final &\b&&\b& or |\b||\b|, any command in a pipeline
+ but the last (subject to the state of the p\bpi\bip\bpe\bef\bfa\bai\bil\bl shell op-
+ tion), or if the command's return value is being inverted using
!\b!. These are the same conditions obeyed by the e\ber\brr\bre\bex\bxi\bit\bt (-\b-e\be) op-
tion.
When the shell is not interactive, signals ignored upon entry to
the shell cannot be trapped or reset. Interactive shells permit
trapping signals ignored on entry. Trapped signals that are not
- being ignored are reset to their original values in a subshell
- or subshell environment when one is created. The return status
+ being ignored are reset to their original values in a subshell
+ or subshell environment when one is created. The return status
is false if any _\bs_\bi_\bg_\bs_\bp_\be_\bc is invalid; otherwise t\btr\bra\bap\bp returns true.
t\btr\bru\bue\be Does nothing, returns a 0 status.
Indicate how each _\bn_\ba_\bm_\be would be interpreted if used as a command
name.
- If the -\b-t\bt option is used, t\bty\byp\bpe\be prints a string which is one of
- _\ba_\bl_\bi_\ba_\bs, _\bk_\be_\by_\bw_\bo_\br_\bd, _\bf_\bu_\bn_\bc_\bt_\bi_\bo_\bn, _\bb_\bu_\bi_\bl_\bt_\bi_\bn, or _\bf_\bi_\bl_\be if _\bn_\ba_\bm_\be is an alias,
- shell reserved word, function, builtin, or executable file, re-
- spectively. If the _\bn_\ba_\bm_\be is not found, t\bty\byp\bpe\be prints nothing and
+ If the -\b-t\bt option is used, t\bty\byp\bpe\be prints a string which is one of
+ _\ba_\bl_\bi_\ba_\bs, _\bk_\be_\by_\bw_\bo_\br_\bd, _\bf_\bu_\bn_\bc_\bt_\bi_\bo_\bn, _\bb_\bu_\bi_\bl_\bt_\bi_\bn, or _\bf_\bi_\bl_\be if _\bn_\ba_\bm_\be is an alias,
+ shell reserved word, function, builtin, or executable file, re-
+ spectively. If the _\bn_\ba_\bm_\be is not found, t\bty\byp\bpe\be prints nothing and
returns a non-zero exit status.
- If the -\b-p\bp option is used, t\bty\byp\bpe\be either returns the pathname of
- the executable file that would be found by searching $\b$P\bPA\bAT\bTH\bH for
+ If the -\b-p\bp option is used, t\bty\byp\bpe\be either returns the pathname of
+ the executable file that would be found by searching $\b$P\bPA\bAT\bTH\bH for
_\bn_\ba_\bm_\be or nothing if "type -t name" would not return _\bf_\bi_\bl_\be. The -\b-P\bP
- option forces a P\bPA\bAT\bTH\bH search for each _\bn_\ba_\bm_\be, even if "type -t
+ option forces a P\bPA\bAT\bTH\bH search for each _\bn_\ba_\bm_\be, even if "type -t
name" would not return _\bf_\bi_\bl_\be. If _\bn_\ba_\bm_\be is present in the table of
- hashed commands, -\b-p\bp and -\b-P\bP print the hashed value, which is not
+ hashed commands, -\b-p\bp and -\b-P\bP print the hashed value, which is not
necessarily the file that appears first in P\bPA\bAT\bTH\bH.
- If the -\b-a\ba option is used, t\bty\byp\bpe\be prints all of the places that
- contain a command named _\bn_\ba_\bm_\be. This includes aliases, reserved
- words, functions, and builtins, but the path search options (-\b-p\bp
- and -\b-P\bP) can be supplied to restrict the output to executable
- files. t\bty\byp\bpe\be does not consult the table of hashed commands when
+ If the -\b-a\ba option is used, t\bty\byp\bpe\be prints all of the places that
+ contain a command named _\bn_\ba_\bm_\be. This includes aliases, reserved
+ words, functions, and builtins, but the path search options (-\b-p\bp
+ and -\b-P\bP) can be supplied to restrict the output to executable
+ files. t\bty\byp\bpe\be does not consult the table of hashed commands when
using -\b-a\ba with -\b-p\bp, and only performs a P\bPA\bAT\bTH\bH search for _\bn_\ba_\bm_\be.
The -\b-f\bf option suppresses shell function lookup, as with the c\bco\bom\bm-\b-
- m\bma\ban\bnd\bd builtin. t\bty\byp\bpe\be returns true if all of the arguments are
+ m\bma\ban\bnd\bd builtin. t\bty\byp\bpe\be returns true if all of the arguments are
found, false if any are not found.
u\bul\bli\bim\bmi\bit\bt [-\b-H\bHS\bS] -\b-a\ba
u\bul\bli\bim\bmi\bit\bt [-\b-H\bHS\bS] [-\b-b\bbc\bcd\bde\bef\bfi\bik\bkl\blm\bmn\bnp\bpq\bqr\brs\bst\btu\buv\bvx\bxP\bPR\bRT\bT [_\bl_\bi_\bm_\bi_\bt]]
- Provides control over the resources available to the shell and
+ Provides control over the resources available to the shell and
to processes it starts, on systems that allow such control.
- The -\b-H\bH and -\b-S\bS options specify whether the hard or soft limit is
+ The -\b-H\bH and -\b-S\bS options specify whether the hard or soft limit is
set for the given resource. A hard limit cannot be increased by
a non-root user once it is set; a soft limit may be increased up
- to the value of the hard limit. If neither -\b-H\bH nor -\b-S\bS is speci-
+ to the value of the hard limit. If neither -\b-H\bH nor -\b-S\bS is speci-
fied, u\bul\bli\bim\bmi\bit\bt sets both the soft and hard limits.
The value of _\bl_\bi_\bm_\bi_\bt can be a number in the unit specified for the
- resource or one of the special values h\bha\bar\brd\bd, s\bso\bof\bft\bt, or u\bun\bnl\bli\bim\bmi\bit\bte\bed\bd,
- which stand for the current hard limit, the current soft limit,
- and no limit, respectively. If _\bl_\bi_\bm_\bi_\bt is omitted, u\bul\bli\bim\bmi\bit\bt prints
- the current value of the soft limit of the resource, unless the
- -\b-H\bH option is given. When more than one resource is specified,
- the limit name and unit, if appropriate, are printed before the
+ resource or one of the special values h\bha\bar\brd\bd, s\bso\bof\bft\bt, or u\bun\bnl\bli\bim\bmi\bit\bte\bed\bd,
+ which stand for the current hard limit, the current soft limit,
+ and no limit, respectively. If _\bl_\bi_\bm_\bi_\bt is omitted, u\bul\bli\bim\bmi\bit\bt prints
+ the current value of the soft limit of the resource, unless the
+ -\b-H\bH option is given. When more than one resource is specified,
+ the limit name and unit, if appropriate, are printed before the
value. Other options are interpreted as follows:
-\b-a\ba Report all current limits; no limits are set.
-\b-b\bb The maximum socket buffer size.
-\b-c\bc The maximum size of core files created.
-\b-d\bd The maximum size of a process's data segment.
-\b-e\be The maximum scheduling priority ("nice").
- -\b-f\bf The maximum size of files written by the shell and its
+ -\b-f\bf The maximum size of files written by the shell and its
children.
-\b-i\bi The maximum number of pending signals.
-\b-k\bk The maximum number of kqueues that may be allocated.
-\b-l\bl The maximum size that may be locked into memory.
- -\b-m\bm The maximum resident set size (many systems do not honor
+ -\b-m\bm The maximum resident set size (many systems do not honor
this limit).
-\b-n\bn The maximum number of open file descriptors (most systems
do not allow this value to be set).
-\b-r\br The maximum real-time scheduling priority.
-\b-s\bs The maximum stack size.
-\b-t\bt The maximum amount of cpu time in seconds.
- -\b-u\bu The maximum number of processes available to a single
+ -\b-u\bu The maximum number of processes available to a single
user.
- -\b-v\bv The maximum amount of virtual memory available to the
+ -\b-v\bv The maximum amount of virtual memory available to the
shell and, on some systems, to its children.
-\b-x\bx The maximum number of file locks.
-\b-P\bP The maximum number of pseudoterminals.
- -\b-R\bR The maximum time a real-time process can run before
+ -\b-R\bR The maximum time a real-time process can run before
blocking, in microseconds.
-\b-T\bT The maximum number of threads.
- If _\bl_\bi_\bm_\bi_\bt is supplied, and the -\b-a\ba option is not used, _\bl_\bi_\bm_\bi_\bt is
- the new value of the specified resource. If no option is sup-
+ If _\bl_\bi_\bm_\bi_\bt is supplied, and the -\b-a\ba option is not used, _\bl_\bi_\bm_\bi_\bt is
+ the new value of the specified resource. If no option is sup-
plied, then -\b-f\bf is assumed.
- Values are in 1024-byte increments, except for -\b-t\bt, which is in
- seconds; -\b-R\bR, which is in microseconds; -\b-p\bp, which is in units of
- 512-byte blocks; -\b-P\bP, -\b-T\bT, -\b-b\bb, -\b-k\bk, -\b-n\bn, and -\b-u\bu, which are unscaled
- values; and, when in posix mode, -\b-c\bc and -\b-f\bf, which are in
- 512-byte increments. The return status is 0 unless an invalid
+ Values are in 1024-byte increments, except for -\b-t\bt, which is in
+ seconds; -\b-R\bR, which is in microseconds; -\b-p\bp, which is in units of
+ 512-byte blocks; -\b-P\bP, -\b-T\bT, -\b-b\bb, -\b-k\bk, -\b-n\bn, and -\b-u\bu, which are unscaled
+ values; and, when in posix mode, -\b-c\bc and -\b-f\bf, which are in
+ 512-byte increments. The return status is 0 unless an invalid
option or argument is supplied, or an error occurs while setting
a new limit.
u\bum\bma\bas\bsk\bk [-\b-p\bp] [-\b-S\bS] [_\bm_\bo_\bd_\be]
- Set the user file-creation mask to _\bm_\bo_\bd_\be. If _\bm_\bo_\bd_\be begins with a
+ Set the user file-creation mask to _\bm_\bo_\bd_\be. If _\bm_\bo_\bd_\be begins with a
digit, it is interpreted as an octal number; otherwise it is in-
- terpreted as a symbolic mode mask similar to that accepted by
+ terpreted as a symbolic mode mask similar to that accepted by
_\bc_\bh_\bm_\bo_\bd(1). If _\bm_\bo_\bd_\be is omitted, u\bum\bma\bas\bsk\bk prints the current value of
the mask. The -\b-S\bS option without a _\bm_\bo_\bd_\be argument prints the mask
in a symbolic format; the default output is an octal number. If
the -\b-p\bp option is supplied, and _\bm_\bo_\bd_\be is omitted, the output is in
- a form that may be reused as input. The return status is zero
- if the mode was successfully changed or if no _\bm_\bo_\bd_\be argument was
+ a form that may be reused as input. The return status is zero
+ if the mode was successfully changed or if no _\bm_\bo_\bd_\be argument was
supplied, and non-zero otherwise.
u\bun\bna\bal\bli\bia\bas\bs [-a\ba] [_\bn_\ba_\bm_\be ...]
- Remove each _\bn_\ba_\bm_\be from the list of defined aliases. If -\b-a\ba is
- supplied, remove all alias definitions. The return value is
+ Remove each _\bn_\ba_\bm_\be from the list of defined aliases. If -\b-a\ba is
+ supplied, remove all alias definitions. The return value is
true unless a supplied _\bn_\ba_\bm_\be is not a defined alias.
u\bun\bns\bse\bet\bt [-f\bfv\bv] [-n\bn] [_\bn_\ba_\bm_\be ...]
- For each _\bn_\ba_\bm_\be, remove the corresponding variable or function.
+ For each _\bn_\ba_\bm_\be, remove the corresponding variable or function.
If the -\b-v\bv option is given, each _\bn_\ba_\bm_\be refers to a shell variable,
- and that variable is removed. If -\b-f\bf is specified, each _\bn_\ba_\bm_\be
- refers to a shell function, and the function definition is re-
- moved. If the -\b-n\bn option is supplied, and _\bn_\ba_\bm_\be is a variable
- with the _\bn_\ba_\bm_\be_\br_\be_\bf attribute, _\bn_\ba_\bm_\be will be unset rather than the
- variable it references. -\b-n\bn has no effect if the -\b-f\bf option is
- supplied. Read-only variables and functions may not be unset.
- When variables or functions are removed, they are also removed
- from the environment passed to subsequent commands. If no op-
- tions are supplied, each _\bn_\ba_\bm_\be refers to a variable; if there is
- no variable by that name, a function with that name, if any, is
- unset. Some shell variables may not be unset. If any of
+ and that variable is removed. If -\b-f\bf is specified, each _\bn_\ba_\bm_\be
+ refers to a shell function, and the function definition is re-
+ moved. If the -\b-n\bn option is supplied, and _\bn_\ba_\bm_\be is a variable
+ with the _\bn_\ba_\bm_\be_\br_\be_\bf attribute, _\bn_\ba_\bm_\be will be unset rather than the
+ variable it references. -\b-n\bn has no effect if the -\b-f\bf option is
+ supplied. Read-only variables and functions may not be unset.
+ When variables or functions are removed, they are also removed
+ from the environment passed to subsequent commands. If no op-
+ tions are supplied, each _\bn_\ba_\bm_\be refers to a variable; if there is
+ no variable by that name, a function with that name, if any, is
+ unset. Some shell variables may not be unset. If any of
B\bBA\bAS\bSH\bH_\b_A\bAL\bLI\bIA\bAS\bSE\bES\bS, B\bBA\bAS\bSH\bH_\b_A\bAR\bRG\bGV\bV0\b0, B\bBA\bAS\bSH\bH_\b_C\bCM\bMD\bDS\bS, B\bBA\bAS\bSH\bH_\b_C\bCO\bOM\bMM\bMA\bAN\bND\bD, B\bBA\bAS\bSH\bH_\b_S\bSU\bUB\bB-\b-
- S\bSH\bHE\bEL\bLL\bL, B\bBA\bAS\bSH\bHP\bPI\bID\bD, C\bCO\bOM\bMP\bP_\b_W\bWO\bOR\bRD\bDB\bBR\bRE\bEA\bAK\bKS\bS, D\bDI\bIR\bRS\bST\bTA\bAC\bCK\bK, E\bEP\bPO\bOC\bCH\bHR\bRE\bEA\bAL\bLT\bTI\bIM\bME\bE,
- E\bEP\bPO\bOC\bCH\bHS\bSE\bEC\bCO\bON\bND\bDS\bS, F\bFU\bUN\bNC\bCN\bNA\bAM\bME\bE, G\bGR\bRO\bOU\bUP\bPS\bS, H\bHI\bIS\bST\bTC\bCM\bMD\bD, L\bLI\bIN\bNE\bEN\bNO\bO, R\bRA\bAN\bND\bDO\bOM\bM, S\bSE\bEC\bC-\b-
- O\bON\bND\bDS\bS, or S\bSR\bRA\bAN\bND\bDO\bOM\bM are unset, they lose their special properties,
- even if they are subsequently reset. The exit status is true
+ S\bSH\bHE\bEL\bLL\bL, B\bBA\bAS\bSH\bHP\bPI\bID\bD, C\bCO\bOM\bMP\bP_\b_W\bWO\bOR\bRD\bDB\bBR\bRE\bEA\bAK\bKS\bS, D\bDI\bIR\bRS\bST\bTA\bAC\bCK\bK, E\bEP\bPO\bOC\bCH\bHR\bRE\bEA\bAL\bLT\bTI\bIM\bME\bE,
+ E\bEP\bPO\bOC\bCH\bHS\bSE\bEC\bCO\bON\bND\bDS\bS, F\bFU\bUN\bNC\bCN\bNA\bAM\bME\bE, G\bGR\bRO\bOU\bUP\bPS\bS, H\bHI\bIS\bST\bTC\bCM\bMD\bD, L\bLI\bIN\bNE\bEN\bNO\bO, R\bRA\bAN\bND\bDO\bOM\bM, S\bSE\bEC\bC-\b-
+ O\bON\bND\bDS\bS, or S\bSR\bRA\bAN\bND\bDO\bOM\bM are unset, they lose their special properties,
+ even if they are subsequently reset. The exit status is true
unless a _\bn_\ba_\bm_\be is readonly or may not be unset.
w\bwa\bai\bit\bt [-\b-f\bfn\bn] [-\b-p\bp _\bv_\ba_\br_\bn_\ba_\bm_\be] [_\bi_\bd ...]
Wait for each specified child process _\bi_\bd and return the termina-
- tion status of the last _\bi_\bd. Each _\bi_\bd may be a process ID _\bp_\bi_\bd or
- a job specification _\bj_\bo_\bb_\bs_\bp_\be_\bc; if a jobspec is supplied, w\bwa\bai\bit\bt
+ tion status of the last _\bi_\bd. Each _\bi_\bd may be a process ID _\bp_\bi_\bd or
+ a job specification _\bj_\bo_\bb_\bs_\bp_\be_\bc; if a jobspec is supplied, w\bwa\bai\bit\bt
waits for all processes in the job.
- If no options or _\bi_\bds are supplied, w\bwa\bai\bit\bt waits for all running
- background jobs and the last-executed process substitution, if
+ If no options or _\bi_\bds are supplied, w\bwa\bai\bit\bt waits for all running
+ background jobs and the last-executed process substitution, if
its process id is the same as $\b$!\b!, and the return status is zero.
- If the -\b-n\bn option is supplied, w\bwa\bai\bit\bt waits for any one of the
+ If the -\b-n\bn option is supplied, w\bwa\bai\bit\bt waits for any one of the
given _\bi_\bds or, if no _\bi_\bds are supplied, any job or process substi-
tution, to complete and returns its exit status. If none of the
- supplied _\bi_\bds is a child of the shell, or if no _\bi_\bds are supplied
- and the shell has no unwaited-for children, the exit status is
+ supplied _\bi_\bds is a child of the shell, or if no _\bi_\bds are supplied
+ and the shell has no unwaited-for children, the exit status is
127.
- If the -\b-p\bp option is supplied, w\bwa\bai\bit\bt assigns the process or job
- identifier of the job for which the exit status is returned to
- the variable _\bv_\ba_\br_\bn_\ba_\bm_\be named by the option argument. The vari-
- able, which cannot be readonly, will be unset initially, before
- any assignment. This is useful only when used with the -\b-n\bn op-
+ If the -\b-p\bp option is supplied, w\bwa\bai\bit\bt assigns the process or job
+ identifier of the job for which the exit status is returned to
+ the variable _\bv_\ba_\br_\bn_\ba_\bm_\be named by the option argument. The vari-
+ able, which cannot be readonly, will be unset initially, before
+ any assignment. This is useful only when used with the -\b-n\bn op-
tion.
- Supplying the -\b-f\bf option, when job control is enabled, forces
- w\bwa\bai\bit\bt to wait for each _\bi_\bd to terminate before returning its sta-
- tus, instead of returning when it changes status. If there are
- no _\bi_\bd arguments, w\bwa\bai\bit\bt waits until all background processes have
+ Supplying the -\b-f\bf option, when job control is enabled, forces
+ w\bwa\bai\bit\bt to wait for each _\bi_\bd to terminate before returning its sta-
+ tus, instead of returning when it changes status. If there are
+ no _\bi_\bd arguments, w\bwa\bai\bit\bt waits until all background processes have
terminated.
- If none of the _\bi_\bds specify one of the shell's active child
- processes, the return status is 127. If w\bwa\bai\bit\bt is interrupted by
- a signal, any _\bv_\ba_\br_\bn_\ba_\bm_\be will remain unset, and the return status
- will be greater than 128, as described under S\bSI\bIG\bGN\bNA\bAL\bLS\bS above.
+ If none of the _\bi_\bds specify one of the shell's active child
+ processes, the return status is 127. If w\bwa\bai\bit\bt is interrupted by
+ a signal, any _\bv_\ba_\br_\bn_\ba_\bm_\be will remain unset, and the return status
+ will be greater than 128, as described under S\bSI\bIG\bGN\bNA\bAL\bLS\bS above.
Otherwise, the return status is the exit status of the last _\bi_\bd.
S\bSH\bHE\bEL\bLL\bL C\bCO\bOM\bMP\bPA\bAT\bTI\bIB\bBI\bIL\bLI\bIT\bTY\bY M\bMO\bOD\bDE\bE
- Bash-4.0 introduced the concept of a _\bs_\bh_\be_\bl_\bl _\bc_\bo_\bm_\bp_\ba_\bt_\bi_\bb_\bi_\bl_\bi_\bt_\by _\bl_\be_\bv_\be_\bl, speci-
+ Bash-4.0 introduced the concept of a _\bs_\bh_\be_\bl_\bl _\bc_\bo_\bm_\bp_\ba_\bt_\bi_\bb_\bi_\bl_\bi_\bt_\by _\bl_\be_\bv_\be_\bl, speci-
fied as a set of options to the shopt builtin (c\bco\bom\bmp\bpa\bat\bt3\b31\b1, c\bco\bom\bmp\bpa\bat\bt3\b32\b2, c\bco\bom\bm-\b-
- p\bpa\bat\bt4\b40\b0, c\bco\bom\bmp\bpa\bat\bt4\b41\b1, and so on). There is only one current compatibility
+ p\bpa\bat\bt4\b40\b0, c\bco\bom\bmp\bpa\bat\bt4\b41\b1, and so on). There is only one current compatibility
level -- each option is mutually exclusive. The compatibility level is
- intended to allow users to select behavior from previous versions that
- is incompatible with newer versions while they migrate scripts to use
- current features and behavior. It's intended to be a temporary solu-
+ intended to allow users to select behavior from previous versions that
+ is incompatible with newer versions while they migrate scripts to use
+ current features and behavior. It's intended to be a temporary solu-
tion.
- This section does not mention behavior that is standard for a particu-
- lar version (e.g., setting c\bco\bom\bmp\bpa\bat\bt3\b32\b2 means that quoting the right hand
- side of the regexp matching operator quotes special regexp characters
- in the word, which is default behavior in bash-3.2 and subsequent ver-
+ This section does not mention behavior that is standard for a particu-
+ lar version (e.g., setting c\bco\bom\bmp\bpa\bat\bt3\b32\b2 means that quoting the right hand
+ side of the regexp matching operator quotes special regexp characters
+ in the word, which is default behavior in bash-3.2 and subsequent ver-
sions).
- If a user enables, say, c\bco\bom\bmp\bpa\bat\bt3\b32\b2, it may affect the behavior of other
- compatibility levels up to and including the current compatibility
- level. The idea is that each compatibility level controls behavior
- that changed in that version of b\bba\bas\bsh\bh, but that behavior may have been
- present in earlier versions. For instance, the change to use locale-
- based comparisons with the [\b[[\b[ command came in bash-4.1, and earlier
+ If a user enables, say, c\bco\bom\bmp\bpa\bat\bt3\b32\b2, it may affect the behavior of other
+ compatibility levels up to and including the current compatibility
+ level. The idea is that each compatibility level controls behavior
+ that changed in that version of b\bba\bas\bsh\bh, but that behavior may have been
+ present in earlier versions. For instance, the change to use locale-
+ based comparisons with the [\b[[\b[ command came in bash-4.1, and earlier
versions used ASCII-based comparisons, so enabling c\bco\bom\bmp\bpa\bat\bt3\b32\b2 will enable
- ASCII-based comparisons as well. That granularity may not be suffi-
- cient for all uses, and as a result users should employ compatibility
- levels carefully. Read the documentation for a particular feature to
+ ASCII-based comparisons as well. That granularity may not be suffi-
+ cient for all uses, and as a result users should employ compatibility
+ levels carefully. Read the documentation for a particular feature to
find out the current behavior.
- Bash-4.3 introduced a new shell variable: B\bBA\bAS\bSH\bH_\b_C\bCO\bOM\bMP\bPA\bAT\bT. The value as-
+ Bash-4.3 introduced a new shell variable: B\bBA\bAS\bSH\bH_\b_C\bCO\bOM\bMP\bPA\bAT\bT. The value as-
signed to this variable (a decimal version number like 4.2, or an inte-
- ger corresponding to the c\bco\bom\bmp\bpa\bat\bt_\bN_\bN option, like 42) determines the com-
+ ger corresponding to the c\bco\bom\bmp\bpa\bat\bt_\bN_\bN option, like 42) determines the com-
patibility level.
Starting with bash-4.4, b\bba\bas\bsh\bh began deprecating older compatibility lev-
els. Eventually, the options will be removed in favor of B\bBA\bAS\bSH\bH_\b_C\bCO\bOM\bMP\bPA\bAT\bT.
- Bash-5.0 was the final version for which there was an individual shopt
- option for the previous version. B\bBA\bAS\bSH\bH_\b_C\bCO\bOM\bMP\bPA\bAT\bT is the only mechanism to
+ Bash-5.0 was the final version for which there was an individual shopt
+ option for the previous version. B\bBA\bAS\bSH\bH_\b_C\bCO\bOM\bMP\bPA\bAT\bT is the only mechanism to
control the compatibility level in versions newer than bash-5.0.
- The following table describes the behavior changes controlled by each
+ The following table describes the behavior changes controlled by each
compatibility level setting. The c\bco\bom\bmp\bpa\bat\bt_\bN_\bN tag is used as shorthand for
setting the compatibility level to _\bN_\bN using one of the following mecha-
- nisms. For versions prior to bash-5.0, the compatibility level may be
- set using the corresponding c\bco\bom\bmp\bpa\bat\bt_\bN_\bN shopt option. For bash-4.3 and
- later versions, the B\bBA\bAS\bSH\bH_\b_C\bCO\bOM\bMP\bPA\bAT\bT variable is preferred, and it is re-
+ nisms. For versions prior to bash-5.0, the compatibility level may be
+ set using the corresponding c\bco\bom\bmp\bpa\bat\bt_\bN_\bN shopt option. For bash-4.3 and
+ later versions, the B\bBA\bAS\bSH\bH_\b_C\bCO\bOM\bMP\bPA\bAT\bT variable is preferred, and it is re-
quired for bash-5.1 and later versions.
c\bco\bom\bmp\bpa\bat\bt3\b31\b1
ator (=~) has no special effect.
c\bco\bom\bmp\bpa\bat\bt3\b32\b2
- +\bo The <\b< and >\b> operators to the [\b[[\b[ command do not consider
+ +\bo The <\b< and >\b> operators to the [\b[[\b[ command do not consider
the current locale when comparing strings; they use ASCII
ordering.
c\bco\bom\bmp\bpa\bat\bt4\b40\b0
- +\bo The <\b< and >\b> operators to the [\b[[\b[ command do not consider
+ +\bo The <\b< and >\b> operators to the [\b[[\b[ command do not consider
the current locale when comparing strings; they use ASCII
ordering. B\bBa\bas\bsh\bh versions prior to bash-4.1 use ASCII col-
- lation and _\bs_\bt_\br_\bc_\bm_\bp(3); bash-4.1 and later use the current
+ lation and _\bs_\bt_\br_\bc_\bm_\bp(3); bash-4.1 and later use the current
locale's collation sequence and _\bs_\bt_\br_\bc_\bo_\bl_\bl(3).
c\bco\bom\bmp\bpa\bat\bt4\b41\b1
- +\bo In posix mode, t\bti\bim\bme\be may be followed by options and still
+ +\bo In posix mode, t\bti\bim\bme\be may be followed by options and still
be recognized as a reserved word (this is POSIX interpre-
tation 267).
+\bo In _\bp_\bo_\bs_\bi_\bx mode, the parser requires that an even number of
- single quotes occur in the _\bw_\bo_\br_\bd portion of a double-
- quoted parameter expansion and treats them specially, so
- that characters within the single quotes are considered
+ single quotes occur in the _\bw_\bo_\br_\bd portion of a double-
+ quoted parameter expansion and treats them specially, so
+ that characters within the single quotes are considered
quoted (this is POSIX interpretation 221).
c\bco\bom\bmp\bpa\bat\bt4\b42\b2
+\bo The replacement string in double-quoted pattern substitu-
- tion does not undergo quote removal, as it does in ver-
+ tion does not undergo quote removal, as it does in ver-
sions after bash-4.2.
- +\bo In posix mode, single quotes are considered special when
- expanding the _\bw_\bo_\br_\bd portion of a double-quoted parameter
- expansion and can be used to quote a closing brace or
- other special character (this is part of POSIX interpre-
- tation 221); in later versions, single quotes are not
+ +\bo In posix mode, single quotes are considered special when
+ expanding the _\bw_\bo_\br_\bd portion of a double-quoted parameter
+ expansion and can be used to quote a closing brace or
+ other special character (this is part of POSIX interpre-
+ tation 221); in later versions, single quotes are not
special within double-quoted word expansions.
c\bco\bom\bmp\bpa\bat\bt4\b43\b3
- +\bo Word expansion errors are considered non-fatal errors
- that cause the current command to fail, even in posix
- mode (the default behavior is to make them fatal errors
+ +\bo Word expansion errors are considered non-fatal errors
+ that cause the current command to fail, even in posix
+ mode (the default behavior is to make them fatal errors
that cause the shell to exit).
- +\bo When executing a shell function, the loop state
+ +\bo When executing a shell function, the loop state
(while/until/etc.) is not reset, so b\bbr\bre\bea\bak\bk or c\bco\bon\bnt\bti\bin\bnu\bue\be in
that function will break or continue loops in the calling
context. Bash-4.4 and later reset the loop state to pre-
vent this.
c\bco\bom\bmp\bpa\bat\bt4\b44\b4
- +\bo The shell sets up the values used by B\bBA\bAS\bSH\bH_\b_A\bAR\bRG\bGV\bV and
- B\bBA\bAS\bSH\bH_\b_A\bAR\bRG\bGC\bC so they can expand to the shell's positional
- parameters even if extended debugging mode is not en-
+ +\bo The shell sets up the values used by B\bBA\bAS\bSH\bH_\b_A\bAR\bRG\bGV\bV and
+ B\bBA\bAS\bSH\bH_\b_A\bAR\bRG\bGC\bC so they can expand to the shell's positional
+ parameters even if extended debugging mode is not en-
abled.
- +\bo A subshell inherits loops from its parent context, so
- b\bbr\bre\bea\bak\bk or c\bco\bon\bnt\bti\bin\bnu\bue\be will cause the subshell to exit.
- Bash-5.0 and later reset the loop state to prevent the
+ +\bo A subshell inherits loops from its parent context, so
+ b\bbr\bre\bea\bak\bk or c\bco\bon\bnt\bti\bin\bnu\bue\be will cause the subshell to exit.
+ Bash-5.0 and later reset the loop state to prevent the
exit
- +\bo Variable assignments preceding builtins like e\bex\bxp\bpo\bor\brt\bt and
+ +\bo Variable assignments preceding builtins like e\bex\bxp\bpo\bor\brt\bt and
r\bre\bea\bad\bdo\bon\bnl\bly\by that set attributes continue to affect variables
with the same name in the calling environment even if the
shell is not in posix mode.
c\bco\bom\bmp\bpa\bat\bt5\b50\b0
- +\bo Bash-5.1 changed the way $\b$R\bRA\bAN\bND\bDO\bOM\bM is generated to intro-
- duce slightly more randomness. If the shell compatibil-
+ +\bo Bash-5.1 changed the way $\b$R\bRA\bAN\bND\bDO\bOM\bM is generated to intro-
+ duce slightly more randomness. If the shell compatibil-
ity level is set to 50 or lower, it reverts to the method
- from bash-5.0 and previous versions, so seeding the ran-
- dom number generator by assigning a value to R\bRA\bAN\bND\bDO\bOM\bM will
+ from bash-5.0 and previous versions, so seeding the ran-
+ dom number generator by assigning a value to R\bRA\bAN\bND\bDO\bOM\bM will
produce the same sequence as in bash-5.0.
- +\bo If the command hash table is empty, bash versions prior
- to bash-5.1 printed an informational message to that ef-
- fect, even when producing output that can be reused as
- input. Bash-5.1 suppresses that message when the -\b-l\bl op-
+ +\bo If the command hash table is empty, bash versions prior
+ to bash-5.1 printed an informational message to that ef-
+ fect, even when producing output that can be reused as
+ input. Bash-5.1 suppresses that message when the -\b-l\bl op-
tion is supplied.
c\bco\bom\bmp\bpa\bat\bt5\b51\b1
- +\bo The u\bun\bns\bse\bet\bt builtin treats attempts to unset array sub-
- scripts @\b@ and *\b* differently depending on whether the ar-
- ray is indexed or associative, and differently than in
+ +\bo The u\bun\bns\bse\bet\bt builtin treats attempts to unset array sub-
+ scripts @\b@ and *\b* differently depending on whether the ar-
+ ray is indexed or associative, and differently than in
previous versions.
+\bo Arithmetic commands ( (\b((\b(...)\b))\b) ) and the expressions in an
arithmetic for statement can be expanded more than once.
- +\bo Expressions used as arguments to arithmetic operators in
- the [\b[[\b[ conditional command can be expanded more than
+ +\bo Expressions used as arguments to arithmetic operators in
+ the [\b[[\b[ conditional command can be expanded more than
once.
- +\bo The expressions in substring parameter brace expansion
+ +\bo The expressions in substring parameter brace expansion
can be expanded more than once.
+\bo The expressions in the $\b$(\b((\b(...)\b))\b) word expansion can be ex-
panded more than once.
- +\bo Arithmetic expressions used as indexed array subscripts
+ +\bo Arithmetic expressions used as indexed array subscripts
can be expanded more than once.
- +\bo t\bte\bes\bst\bt -\b-v\bv, when given an argument of A\bA[\b[@\b@]\b], where A\bA is an
+ +\bo t\bte\bes\bst\bt -\b-v\bv, when given an argument of A\bA[\b[@\b@]\b], where A\bA is an
existing associative array, will return true if the array
- has any set elements. Bash-5.2 will look for and report
+ has any set elements. Bash-5.2 will look for and report
on a key named @\b@.
+\bo The ${_\bp_\ba_\br_\ba_\bm_\be_\bt_\be_\br[\b[:\b:]\b]=\b=_\bv_\ba_\bl_\bu_\be} word expansion will return
- _\bv_\ba_\bl_\bu_\be, before any variable-specific transformations have
+ _\bv_\ba_\bl_\bu_\be, before any variable-specific transformations have
been performed (e.g., converting to lowercase). Bash-5.2
will return the final value assigned to the variable.
- +\bo Parsing command substitutions will behave as if extended
+ +\bo Parsing command substitutions will behave as if extended
globbing (see the description of the s\bsh\bho\bop\bpt\bt builtin above)
- is enabled, so that parsing a command substitution con-
+ is enabled, so that parsing a command substitution con-
taining an extglob pattern (say, as part of a shell func-
- tion) will not fail. This assumes the intent is to en-
- able extglob before the command is executed and word ex-
- pansions are performed. It will fail at word expansion
- time if extglob hasn't been enabled by the time the com-
+ tion) will not fail. This assumes the intent is to en-
+ able extglob before the command is executed and word ex-
+ pansions are performed. It will fail at word expansion
+ time if extglob hasn't been enabled by the time the com-
mand is executed.
c\bco\bom\bmp\bpa\bat\bt5\b52\b2
- +\bo The t\bte\bes\bst\bt builtin uses its historical algorithm to parse
- parenthesized subexpressions when given five or more ar-
+ +\bo The t\bte\bes\bst\bt builtin uses its historical algorithm to parse
+ parenthesized subexpressions when given five or more ar-
guments.
- +\bo If the -\b-p\bp or -\b-P\bP option is supplied to the b\bbi\bin\bnd\bd builtin,
+ +\bo If the -\b-p\bp or -\b-P\bP option is supplied to the b\bbi\bin\bnd\bd builtin,
b\bbi\bin\bnd\bd treats any arguments remaining after option process-
- ing as bindable command names, and displays any key se-
- quences bound to those commands, instead of treating the
+ ing as bindable command names, and displays any key se-
+ quences bound to those commands, instead of treating the
arguments as key sequences to bind.
R\bRE\bES\bST\bTR\bRI\bIC\bCT\bTE\bED\bD S\bSH\bHE\bEL\bLL\bL
If b\bba\bas\bsh\bh is started with the name r\brb\bba\bas\bsh\bh, or the -\b-r\br option is supplied at
- invocation, the shell becomes _\br_\be_\bs_\bt_\br_\bi_\bc_\bt_\be_\bd. A restricted shell is used
- to set up an environment more controlled than the standard shell. It
- behaves identically to b\bba\bas\bsh\bh with the exception that the following are
+ invocation, the shell becomes _\br_\be_\bs_\bt_\br_\bi_\bc_\bt_\be_\bd. A restricted shell is used
+ to set up an environment more controlled than the standard shell. It
+ behaves identically to b\bba\bas\bsh\bh with the exception that the following are
disallowed or not performed:
+\bo Changing directories with c\bcd\bd.
- +\bo Setting or unsetting the values of S\bSH\bHE\bEL\bLL\bL, P\bPA\bAT\bTH\bH, H\bHI\bIS\bST\bTF\bFI\bIL\bLE\bE, E\bEN\bNV\bV,
+ +\bo Setting or unsetting the values of S\bSH\bHE\bEL\bLL\bL, P\bPA\bAT\bTH\bH, H\bHI\bIS\bST\bTF\bFI\bIL\bLE\bE, E\bEN\bNV\bV,
or B\bBA\bAS\bSH\bH_\b_E\bEN\bNV\bV.
+\bo Specifying command names containing /\b/.
- +\bo Specifying a filename containing a /\b/ as an argument to the .\b.
+ +\bo Specifying a filename containing a /\b/ as an argument to the .\b.
builtin command.
- +\bo Using the -\b-p\bp option to the .\b. builtin command to specify a
+ +\bo Using the -\b-p\bp option to the .\b. builtin command to specify a
search path.
- +\bo Specifying a filename containing a slash as an argument to the
+ +\bo Specifying a filename containing a slash as an argument to the
h\bhi\bis\bst\bto\bor\bry\by builtin command.
- +\bo Specifying a filename containing a slash as an argument to the
+ +\bo Specifying a filename containing a slash as an argument to the
-\b-p\bp option to the h\bha\bas\bsh\bh builtin command.
- +\bo Importing function definitions from the shell environment at
+ +\bo Importing function definitions from the shell environment at
startup.
- +\bo Parsing the values of B\bBA\bAS\bSH\bHO\bOP\bPT\bTS\bS and S\bSH\bHE\bEL\bLL\bLO\bOP\bPT\bTS\bS from the shell en-
+ +\bo Parsing the values of B\bBA\bAS\bSH\bHO\bOP\bPT\bTS\bS and S\bSH\bHE\bEL\bLL\bLO\bOP\bPT\bTS\bS from the shell en-
vironment at startup.
- +\bo Redirecting output using the >, >|, <>, >&, &>, and >> redirec-
+ +\bo Redirecting output using the >, >|, <>, >&, &>, and >> redirec-
tion operators.
+\bo Using the e\bex\bxe\bec\bc builtin command to replace the shell with another
command.
- +\bo Adding or deleting builtin commands with the -\b-f\bf and -\b-d\bd options
+ +\bo Adding or deleting builtin commands with the -\b-f\bf and -\b-d\bd options
to the e\ben\bna\bab\bbl\ble\be builtin command.
- +\bo Using the e\ben\bna\bab\bbl\ble\be builtin command to enable disabled shell
+ +\bo Using the e\ben\bna\bab\bbl\ble\be builtin command to enable disabled shell
builtins.
+\bo Specifying the -\b-p\bp option to the c\bco\bom\bmm\bma\ban\bnd\bd builtin command.
- +\bo Turning off restricted mode with s\bse\bet\bt +\b+r\br or s\bsh\bho\bop\bpt\bt -\b-u\bu r\bre\be-\b-
+ +\bo Turning off restricted mode with s\bse\bet\bt +\b+r\br or s\bsh\bho\bop\bpt\bt -\b-u\bu r\bre\be-\b-
s\bst\btr\bri\bic\bct\bte\bed\bd_\b_s\bsh\bhe\bel\bll\bl.
These restrictions are enforced after any startup files are read.
When a command that is found to be a shell script is executed (see C\bCO\bOM\bM-\b-
- M\bMA\bAN\bND\bD E\bEX\bXE\bEC\bCU\bUT\bTI\bIO\bON\bN above), r\brb\bba\bas\bsh\bh turns off any restrictions in the shell
+ M\bMA\bAN\bND\bD E\bEX\bXE\bEC\bCU\bUT\bTI\bIO\bON\bN above), r\brb\bba\bas\bsh\bh turns off any restrictions in the shell
spawned to execute the script.
S\bSE\bEE\bE A\bAL\bLS\bSO\bO
_\b~_\b/_\b._\bb_\ba_\bs_\bh_\br_\bc
The individual per-interactive-shell startup file
_\b~_\b/_\b._\bb_\ba_\bs_\bh_\b__\bl_\bo_\bg_\bo_\bu_\bt
- The individual login shell cleanup file, executed when a login
+ The individual login shell cleanup file, executed when a login
shell exits
_\b~_\b/_\b._\bb_\ba_\bs_\bh_\b__\bh_\bi_\bs_\bt_\bo_\br_\by
- The default value of H\bHI\bIS\bST\bTF\bFI\bIL\bLE\bE, the file in which bash saves the
+ The default value of H\bHI\bIS\bST\bTF\bFI\bIL\bLE\bE, the file in which bash saves the
command history
_\b~_\b/_\b._\bi_\bn_\bp_\bu_\bt_\br_\bc
Individual _\br_\be_\ba_\bd_\bl_\bi_\bn_\be initialization file
B\bBU\bUG\bG R\bRE\bEP\bPO\bOR\bRT\bTS\bS
If you find a bug in b\bba\bas\bsh\bh, you should report it. But first, you should
- make sure that it really is a bug, and that it appears in the latest
- version of b\bba\bas\bsh\bh. The latest version is always available from
+ make sure that it really is a bug, and that it appears in the latest
+ version of b\bba\bas\bsh\bh. The latest version is always available from
<ftp://ftp.gnu.org/pub/gnu/bash/> and <http://git.savannah.gnu.org/
cgit/bash.git/snapshot/bash-master.tar.gz>.
- Once you have determined that a bug actually exists, use the _\bb_\ba_\bs_\bh_\bb_\bu_\bg
- command to submit a bug report. If you have a fix, you are encouraged
+ Once you have determined that a bug actually exists, use the _\bb_\ba_\bs_\bh_\bb_\bu_\bg
+ command to submit a bug report. If you have a fix, you are encouraged
to mail that as well! You may send suggestions and "philosophical" bug
- reports, as well as comments and bug reports concerning this manual
+ reports, as well as comments and bug reports concerning this manual
page, to to <bug-bash@gnu.org>.
_\bA_\bl_\bl bug reports should include:
+\bo the version number of b\bba\bas\bsh\bh ("echo $BASH_VERSION"),
+\bo the host platform and operating system ("uname -a"),
+\bo either
- (a) if you or an administrator built and installed b\bba\bas\bsh\bh from
- source, the name and version of the compiler used to build it,
+ (a) if you or an administrator built and installed b\bba\bas\bsh\bh from
+ source, the name and version of the compiler used to build it,
as reported by b\bba\bas\bsh\bh's "configure" script; or
- (b) if your site uses a distributor's b\bba\bas\bsh\bh package, the version of
+ (b) if your site uses a distributor's b\bba\bas\bsh\bh package, the version of
that package (for example, "dpkg -i bash" or "rpm -qi bash"),
+\bo a description of the behavior b\bba\bas\bsh\bh exhibited,
+\bo a description of the behavior you expected from b\bba\bas\bsh\bh, and
+\bo a short shell script or "recipe" exercising the unexpected behavior.
- _\bb_\ba_\bs_\bh_\bb_\bu_\bg inserts the first three items automatically into the template
+ _\bb_\ba_\bs_\bh_\bb_\bu_\bg inserts the first three items automatically into the template
it provides for filing a bug report.
B\bBU\bUG\bGS\bS
It's too big and too slow.
- There are some subtle differences between b\bba\bas\bsh\bh and historical versions
- of s\bsh\bh, due mostly to b\bba\bas\bsh\bh's independent implementation and the evolu-
+ There are some subtle differences between b\bba\bas\bsh\bh and historical versions
+ of s\bsh\bh, due mostly to b\bba\bas\bsh\bh's independent implementation and the evolu-
tion of the POSIX specification.
Aliases are confusing in some uses.
Shell builtin commands and functions are not stoppable/restartable.
- Compound commands and command lists of the form "a ; b ; c" are not
- handled gracefully when combined with process suspension. When a
- process is stopped, the shell immediately executes the next command in
- the list or breaks out of any existing loops. It suffices to enclose
- the command in parentheses to force it into a subshell, which may be
- stopped as a unit, or to start the command in the background and imme-
+ Compound commands and command lists of the form "a ; b ; c" are not
+ handled gracefully when combined with process suspension. When a
+ process is stopped, the shell immediately executes the next command in
+ the list or breaks out of any existing loops. It suffices to enclose
+ the command in parentheses to force it into a subshell, which may be
+ stopped as a unit, or to start the command in the background and imme-
diately bring it into the foreground.
Array variables may not (yet) be exported.
-GNU Bash 5.3 2025 December 2 _\bB_\bA_\bS_\bH(1)
+GNU Bash 5.3 2025 December 18 _\bB_\bA_\bS_\bH(1)
projects / thirdparty / bash.git / commitdiff
