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 op-
erand must be a separate argument. Expressions are composed of
- the primaries described in the b\bba\bas\bsh\bh manual page under C\bCO\bON\bND\bDI\bI-\b-
- T\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.
+ 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,
+ Expressions may be combined using the following operators,
listed in decreasing order of precedence. The evaluation
- depends on the number of arguments; see below. Operator prece-
+ depends on the number of arguments; see below. Operator prece-
dence is used 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
the normal precedence of operators.
_\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
If the first argument is !\b!, the result is the negation of
- the three-argument expression composed of the remaining
+ the three-argument expression composed of the remaining
arguments. Otherwise, the expression is parsed and eval-
- uated according to precedence using the rules listed
+ uated 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 used with t\bte\bes\bst\bt or [\b[, the <\b< and >\b> operators sort lexico-
+ When used with t\bte\bes\bst\bt or [\b[, the <\b< and >\b> operators sort lexico-
graphically using ASCII ordering.
- 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\bp] [[_\ba_\br_\bg] _\bs_\bi_\bg_\bs_\bp_\be_\bc ...]
- The command _\ba_\br_\bg is to be read and executed when the shell
- receives signal(s) _\bs_\bi_\bg_\bs_\bp_\be_\bc. If _\ba_\br_\bg is absent (and there is a
- single _\bs_\bi_\bg_\bs_\bp_\be_\bc) or -\b-, each specified signal is reset to its
- original disposition (the value it had upon entrance to the
- shell). If _\ba_\br_\bg 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 _\ba_\br_\bg is not present and -\b-p\bp has been supplied, then the trap
- commands associated with each _\bs_\bi_\bg_\bs_\bp_\be_\bc are displayed. If no
- arguments are supplied or if only -\b-p\bp is given, t\btr\bra\bap\bp prints the
- list of commands associated with each signal. The -\b-l\bl option
- causes the shell to print a list of signal names and their cor-
- responding 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
+ The command _\ba_\br_\bg is to be read and executed when the shell
+ receives signal(s) _\bs_\bi_\bg_\bs_\bp_\be_\bc. If _\ba_\br_\bg is absent (and there is a
+ single _\bs_\bi_\bg_\bs_\bp_\be_\bc) or -\b-, each specified signal is reset to its
+ original disposition (the value it had upon entrance to the
+ shell). If _\ba_\br_\bg 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 _\ba_\br_\bg is not present and -\b-p\bp has been supplied, then the trap
+ commands associated with each _\bs_\bi_\bg_\bs_\bp_\be_\bc are displayed. If no
+ arguments are supplied or if only -\b-p\bp is given, t\btr\bra\bap\bp prints the
+ list of commands associated with each signal. The -\b-l\bl option
+ causes the shell to print a list of signal names and their cor-
+ responding 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 insensitive and the S\bSI\bIG\bG prefix is optional.
- If a _\bs_\bi_\bg_\bs_\bp_\be_\bc is E\bEX\bXI\bIT\bT (0) the command _\ba_\br_\bg is executed on exit
- from the shell. If a _\bs_\bi_\bg_\bs_\bp_\be_\bc is D\bDE\bEB\bBU\bUG\bG, the command _\ba_\br_\bg is exe-
- cuted 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, every arithmetic _\bf_\bo_\br command, 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 option to the
+ If a _\bs_\bi_\bg_\bs_\bp_\be_\bc is E\bEX\bXI\bIT\bT (0) the command _\ba_\br_\bg is executed on exit
+ from the shell. If a _\bs_\bi_\bg_\bs_\bp_\be_\bc is D\bDE\bEB\bBU\bUG\bG, the command _\ba_\br_\bg is exe-
+ cuted 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, every arithmetic _\bf_\bo_\br command, 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 option to the
s\bsh\bho\bop\bpt\bt builtin for details of its effect 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, the command _\ba_\br_\bg is executed each time a shell
function or a script executed with the .\b. or s\bso\bou\bur\brc\bce\be builtins fin-
ishes executing.
- If a _\bs_\bi_\bg_\bs_\bp_\be_\bc is E\bER\bRR\bR, the command _\ba_\br_\bg is executed whenever a
+ If a _\bs_\bi_\bg_\bs_\bp_\be_\bc is E\bER\bRR\bR, the command _\ba_\br_\bg 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
+ 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 keyword, part of the test in an _\bi_\bf statement,
+ a w\bwh\bhi\bil\ble\be or u\bun\bnt\bti\bil\bl keyword, part of the test in an _\bi_\bf statement,
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, 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)
+ following the final &\b&&\b& or |\b||\b|, any command in a pipeline but the
+ last, 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)
option.
- Signals ignored upon entry to the shell cannot be trapped or
- reset. Trapped signals that are not being ignored are reset to
+ Signals ignored upon entry to the shell cannot be trapped or
+ reset. Trapped signals that are not being ignored are reset to
their original values in a subshell or subshell environment when
- one is created. The return status is false if any _\bs_\bi_\bg_\bs_\bp_\be_\bc is
+ 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\bty\byp\bpe\be [-\b-a\baf\bft\btp\bpP\bP] _\bn_\ba_\bm_\be [_\bn_\ba_\bm_\be ...]
- With no options, indicate how each _\bn_\ba_\bm_\be would be interpreted if
+ With no options, 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 disk file, respectively. If the _\bn_\ba_\bm_\be is not found,
- then nothing is printed, and an exit status of false is
- returned. If the -\b-p\bp option is used, t\bty\byp\bpe\be either returns the
+ 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 disk file, respectively. If the _\bn_\ba_\bm_\be is not found,
+ then nothing is printed, and an exit status of false is
+ returned. If the -\b-p\bp option is used, t\bty\byp\bpe\be either returns the
name of the disk file that would be executed if _\bn_\ba_\bm_\be were speci-
fied as a command name, 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,
+ 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 name'' would not return _\bf_\bi_\bl_\be. If a command is
hashed, -\b-p\bp and -\b-P\bP print the hashed value, which is not necessar-
- ily 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 an executable
+ ily 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 an executable
named _\bn_\ba_\bm_\be. This includes aliases and functions, if and only if
the -\b-p\bp option is not also used. The table of hashed commands is
- not consulted when using -\b-a\ba. The -\b-f\bf option suppresses shell
+ not consulted when using -\b-a\ba. The -\b-f\bf option suppresses shell
function lookup, as with the c\bco\bom\bmm\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\bSa\bab\bbc\bcd\bde\bef\bfi\bik\bkl\blm\bmn\bnp\bpq\bqr\brs\bst\btu\buv\bvx\bxP\bPT\bT [_\bl_\bi_\bm_\bi_\bt]]
- Provides control over the resources available to the shell and
- to processes started by it, on systems that allow such control.
+ Provides control over the resources available to the shell and
+ to processes started by it, on systems that allow such control.
The -\b-H\bH and -\b-S\bS options specify that the hard or soft limit is set
- for the given resource. A hard limit cannot be increased by a
- non-root user once it is set; a soft limit may be increased up
- to the value of the hard limit. If neither -\b-H\bH nor -\b-S\bS is speci-
+ 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-
fied, both the soft and hard limits are set. 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, the current value of the
- soft limit of the resource is printed, unless the -\b-H\bH option is
+ current hard limit, the current soft limit, and no limit,
+ respectively. If _\bl_\bi_\bm_\bi_\bt is omitted, the current value of the
+ soft limit of the resource is printed, unless the -\b-H\bH option is
given. When more than one resource is specified, the limit name
and unit are printed before the value. Other options are inter-
preted as follows:
-\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-T\bT The maximum number of threads
- If _\bl_\bi_\bm_\bi_\bt is given, 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 given,
- then -\b-f\bf is assumed. Values are in 1024-byte increments, except
- for -\b-t\bt, which is in seconds; -\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;
+ If _\bl_\bi_\bm_\bi_\bt is given, 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 given,
+ then -\b-f\bf is assumed. Values are in 1024-byte increments, except
+ for -\b-t\bt, which is in seconds; -\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 incre-
ments. The return status is 0 unless an invalid option or argu-
ment 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]
The user file-creation mask is set to _\bm_\bo_\bd_\be. If _\bm_\bo_\bd_\be begins with
- a digit, it is interpreted as an octal number; otherwise it is
- interpreted as a symbolic mode mask similar to that accepted by
- _\bc_\bh_\bm_\bo_\bd(1). If _\bm_\bo_\bd_\be is omitted, the current value of the mask is
- printed. The -\b-S\bS option causes the mask to be printed in sym-
- bolic form; the default output is an octal number. If the -\b-p\bp
+ a digit, it is interpreted as an octal number; otherwise it is
+ interpreted as a symbolic mode mask similar to that accepted by
+ _\bc_\bh_\bm_\bo_\bd(1). If _\bm_\bo_\bd_\be is omitted, the current value of the mask is
+ printed. The -\b-S\bS option causes the mask to be printed in sym-
+ bolic form; 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 0 if the mode
- was successfully changed or if no _\bm_\bo_\bd_\be argument was supplied,
+ was successfully changed or if no _\bm_\bo_\bd_\be argument was supplied,
and false 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, all alias definitions are removed. The return value
+ Remove each _\bn_\ba_\bm_\be from the list of defined aliases. If -\b-a\ba is
+ supplied, all alias definitions are removed. 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. Read-only variables may not be
- unset. If -\b-f\bf is specified, each _\bn_\ba_\bm_\be refers to a shell func-
- tion, and the function definition is removed. 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. If no options are
- supplied, each _\bn_\ba_\bm_\be refers to a variable; if there is no vari-
- able by that name, any function with that name is unset. Each
- unset variable or function is removed from the environment
- passed to subsequent commands. If any of C\bCO\bOM\bMP\bP_\b_W\bWO\bOR\bRD\bDB\bBR\bRE\bEA\bAK\bKS\bS, R\bRA\bAN\bN-\b-
+ and that variable is removed. Read-only variables may not be
+ unset. If -\b-f\bf is specified, each _\bn_\ba_\bm_\be refers to a shell func-
+ tion, and the function definition is removed. 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. If no options are
+ supplied, each _\bn_\ba_\bm_\be refers to a variable; if there is no vari-
+ able by that name, any function with that name is unset. Each
+ unset variable or function is removed from the environment
+ passed to subsequent commands. If any of C\bCO\bOM\bMP\bP_\b_W\bWO\bOR\bRD\bDB\bBR\bRE\bEA\bAK\bKS\bS, R\bRA\bAN\bN-\b-
D\bDO\bOM\bM, S\bSE\bEC\bCO\bON\bND\bDS\bS, L\bLI\bIN\bNE\bEN\bNO\bO, H\bHI\bIS\bST\bTC\bCM\bMD\bD, F\bFU\bUN\bNC\bCN\bNA\bAM\bME\bE, G\bGR\bRO\bOU\bUP\bPS\bS, or D\bDI\bIR\bRS\bST\bTA\bAC\bCK\bK are
unset, they lose their special properties, even if they are sub-
sequently reset. The exit status is true unless a _\bn_\ba_\bm_\be is read-
w\bwa\bai\bit\bt [-\b-f\bfn\bn] [_\bi_\bd _\b._\b._\b.]
Wait for each specified child process and return its termination
- status. Each _\bi_\bd may be a process ID or a job specification; if
- a job spec is given, all processes in that job's pipeline are
- waited for. If _\bi_\bd is not given, w\bwa\bai\bit\bt waits for all running
- background jobs and the last-executed process substitution, if
+ status. Each _\bi_\bd may be a process ID or a job specification; if
+ a job spec is given, all processes in that job's pipeline are
+ waited for. If _\bi_\bd is not given, 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 a single job to
+ If the -\b-n\bn option is supplied, w\bwa\bai\bit\bt waits for a single job to
terminate and returns its exit status. Supplying the -\b-f\bf option,
- when job control is enabled, forces w\bwa\bai\bit\bt to wait for _\bi_\bd to ter-
+ when job control is enabled, forces w\bwa\bai\bit\bt to wait for _\bi_\bd to ter-
minate before returning its status, instead of returning when it
- changes status. If _\bi_\bd specifies a non-existent process or job,
- the return status is 127. Otherwise, the return status is the
+ changes status. If _\bi_\bd specifies a non-existent process or job,
+ the return status is 127. Otherwise, the return status is the
exit status of the last process or job waited for.
S\bSE\bEE\bE A\bAL\bLS\bSO\bO
projects / thirdparty / bash.git / commitdiff
