mirror of
https://https.git.savannah.gnu.org/git/bash.git
synced 2026-08-06 10:12:38 +02:00
bash-5.0-alpha release
This commit is contained in:
Chet Ramey
+404
-81
@@ -3,7 +3,7 @@
|
||||
</HEAD>
|
||||
<BODY><TABLE WIDTH=100%>
|
||||
<TR>
|
||||
<TH ALIGN=LEFT width=33%>BASH(1)<TH ALIGN=CENTER width=33%>2016 August 26<TH ALIGN=RIGHT width=33%>BASH(1)
|
||||
<TH ALIGN=LEFT width=33%>BASH(1)<TH ALIGN=CENTER width=33%>2018 March 15<TH ALIGN=RIGHT width=33%>BASH(1)
|
||||
</TR>
|
||||
</TABLE>
|
||||
<BR><A HREF="#index">Index</A>
|
||||
@@ -42,7 +42,7 @@ bash - GNU Bourne-Again SHell
|
||||
<H3>COPYRIGHT</H3>
|
||||
|
||||
|
||||
Bash is Copyright © 1989-2016 by the Free Software Foundation, Inc.
|
||||
Bash is Copyright © 1989-2018 by the Free Software Foundation, Inc.
|
||||
<A NAME="lbAE"> </A>
|
||||
<H3>DESCRIPTION</H3>
|
||||
|
||||
@@ -68,8 +68,8 @@ can be configured to be POSIX-conformant by default.
|
||||
<H3>OPTIONS</H3>
|
||||
|
||||
All of the single-character shell options documented in the
|
||||
description of the <B>set</B> builtin command can be used as options
|
||||
when the shell is invoked.
|
||||
description of the <B>set</B> builtin command, including <B>-o</B>,
|
||||
can be used as options when the shell is invoked.
|
||||
In addition, <B>bash</B>
|
||||
interprets the following options when it is invoked:
|
||||
<P>
|
||||
@@ -139,7 +139,8 @@ If the
|
||||
option is present, or if no arguments remain after option
|
||||
processing, then commands are read from the standard input.
|
||||
This option allows the positional parameters to be set
|
||||
when invoking an interactive shell.
|
||||
when invoking an interactive shell or when reading input
|
||||
through a pipe.
|
||||
<DT><B>-D</B>
|
||||
|
||||
<DD>
|
||||
@@ -780,6 +781,12 @@ the time information.
|
||||
|
||||
Each command in a pipeline is executed as a separate process (i.e., in a
|
||||
subshell).
|
||||
See
|
||||
<FONT SIZE=-1><B>COMMAND EXECUTION ENVIRONMENT</B></FONT>
|
||||
for a description of a subshell environment.
|
||||
If the <B>lastpipe</B> option is enabled using the <B>shopt</B> builtin
|
||||
(see the description of <B>shopt</B> below),
|
||||
the last element of a pipeline may be run by the shell process.
|
||||
<A NAME="lbAN"> </A>
|
||||
<H4>Lists</H4>
|
||||
|
||||
@@ -855,7 +862,7 @@ An AND list has the form
|
||||
is executed if, and only if,
|
||||
<I>command1</I>
|
||||
|
||||
returns an exit status of zero.
|
||||
returns an exit status of zero (success).
|
||||
<P>
|
||||
|
||||
An OR list has the form
|
||||
@@ -871,7 +878,7 @@ An OR list has the form
|
||||
|
||||
<I>command2</I>
|
||||
|
||||
is executed if and only if
|
||||
is executed if, and only if,
|
||||
<I>command1</I>
|
||||
|
||||
returns a non-zero exit status.
|
||||
@@ -1110,11 +1117,11 @@ or zero if no commands were executed.
|
||||
<DT><B>case</B> <I>word</I> <B>in</B> [ [(] <I>pattern</I> [ <B>|</B> <I>pattern</I> ]
|
||||
<DD>
|
||||
A <B>case</B> command first expands <I>word</I>, and tries to match
|
||||
it against each <I>pattern</I> in turn, using the same matching rules
|
||||
as for pathname expansion (see
|
||||
<B>Pathname Expansion</B>
|
||||
it against each <I>pattern</I> in turn, using the matching rules
|
||||
described under
|
||||
<B>Pattern Matching</B>
|
||||
|
||||
below).
|
||||
below.
|
||||
The <I>word</I> is expanded using tilde
|
||||
expansion, parameter and variable expansion, arithmetic expansion,
|
||||
command substitution, process substitution and quote removal.
|
||||
@@ -1217,7 +1224,8 @@ command (see
|
||||
below).
|
||||
The file descriptors can be utilized as arguments to shell commands
|
||||
and redirections using standard word expansions.
|
||||
The file descriptors are not available in subshells.
|
||||
Other than those created to execute command and process substitutions,
|
||||
the file descriptors are not available in subshells.
|
||||
The process ID of the shell spawned to execute the coprocess is
|
||||
available as the value of the variable <I>NAME</I>_PID.
|
||||
The <B>wait</B>
|
||||
@@ -1463,7 +1471,7 @@ question mark
|
||||
|
||||
<DD>
|
||||
the eight-bit character whose value is the octal value <I>nnn</I>
|
||||
(one to three digits)
|
||||
(one to three octal digits)
|
||||
<DT><B>\x</B><I>HH</I>
|
||||
|
||||
<DD>
|
||||
@@ -1868,6 +1876,16 @@ This variable is read-only.
|
||||
Expands to the process ID of the current <B>bash</B> process.
|
||||
This differs from <B>$$</B> under certain circumstances, such as subshells
|
||||
that do not require <B>bash</B> to be re-initialized.
|
||||
Assignments to
|
||||
<FONT SIZE=-1><B>BASHPID</B>
|
||||
|
||||
</FONT>
|
||||
have no effect.
|
||||
If
|
||||
<B>BASHPID</B>
|
||||
|
||||
is unset, it loses its special properties, even if it is
|
||||
subsequently reset.
|
||||
<DT><B>BASH_ALIASES</B>
|
||||
|
||||
<DD>
|
||||
@@ -1903,7 +1921,9 @@ only when in extended debugging mode (see the description of the
|
||||
option to the
|
||||
<B>shopt</B>
|
||||
|
||||
builtin below)
|
||||
builtin below).
|
||||
Setting <B>extdebug</B> after the shell has started to execute a script
|
||||
may result in inconsistent values.
|
||||
<DT><B>BASH_ARGV</B>
|
||||
|
||||
<DD>
|
||||
@@ -1926,7 +1946,26 @@ only when in extended debugging mode
|
||||
option to the
|
||||
<B>shopt</B>
|
||||
|
||||
builtin below)
|
||||
builtin below).
|
||||
Setting <B>extdebug</B> after the shell has started to execute a script
|
||||
may result in inconsistent values.
|
||||
<DT><B>BASH_ARGV0</B>
|
||||
|
||||
<DD>
|
||||
When referenced, this variable expands to the name of the shell or shell
|
||||
script (identical to
|
||||
<B>$0</B>;
|
||||
|
||||
see the description of special parameter 0 above).
|
||||
Assignment to
|
||||
<B>BASH_ARGV0</B>
|
||||
|
||||
causes the value assigned to also be assigned to <B>$0</B>.
|
||||
If
|
||||
<B>BASH_ARGV0</B>
|
||||
|
||||
is unset, it loses its special properties, even if it is
|
||||
subsequently reset.
|
||||
<DT><B>BASH_CMDS</B>
|
||||
|
||||
<DD>
|
||||
@@ -2152,6 +2191,39 @@ Assignment to this variable will not change the current directory.
|
||||
If
|
||||
<FONT SIZE=-1><B>DIRSTACK</B>
|
||||
|
||||
</FONT>
|
||||
is unset, it loses its special properties, even if it is
|
||||
subsequently reset.
|
||||
<DT><B>EPOCHREALTIME</B>
|
||||
|
||||
<DD>
|
||||
Each time this parameter is referenced, it expands to the number of seconds
|
||||
since the Unix Epoch (see <I>time</I>(3)) as a floating point value
|
||||
with micro-second granularity.
|
||||
Assignments to
|
||||
<FONT SIZE=-1><B>EPOCHREALTIME</B>
|
||||
|
||||
</FONT>
|
||||
are ignored.
|
||||
If
|
||||
<FONT SIZE=-1><B>EPOCHREALTIME</B>
|
||||
|
||||
</FONT>
|
||||
is unset, it loses its special properties, even if it is
|
||||
subsequently reset.
|
||||
<DT><B>EPOCHSECONDS</B>
|
||||
|
||||
<DD>
|
||||
Each time this parameter is referenced, it expands to the number of seconds
|
||||
since the Unix Epoch (see <I>time</I>(3)).
|
||||
Assignments to
|
||||
<FONT SIZE=-1><B>EPOCHSECONDS</B>
|
||||
|
||||
</FONT>
|
||||
are ignored.
|
||||
If
|
||||
<FONT SIZE=-1><B>EPOCHSECONDS</B>
|
||||
|
||||
</FONT>
|
||||
is unset, it loses its special properties, even if it is
|
||||
subsequently reset.
|
||||
@@ -2612,9 +2684,9 @@ will cause the current command to abort.
|
||||
<DT><B>GLOBIGNORE</B>
|
||||
|
||||
<DD>
|
||||
A colon-separated list of patterns defining the set of filenames to
|
||||
A colon-separated list of patterns defining the set of file names to
|
||||
be ignored by pathname expansion.
|
||||
If a filename matched by a pathname expansion pattern also matches one
|
||||
If a file name matched by a pathname expansion pattern also matches one
|
||||
of the patterns in
|
||||
<FONT SIZE=-1><B>GLOBIGNORE</B>,
|
||||
|
||||
@@ -3035,6 +3107,7 @@ and the value is printed before each command
|
||||
<B>bash</B>
|
||||
|
||||
displays during an execution trace. The first character of
|
||||
the expanded value of
|
||||
<FONT SIZE=-1><B>PS4</B>
|
||||
|
||||
</FONT>
|
||||
@@ -3327,15 +3400,21 @@ The
|
||||
<B>unset</B>
|
||||
|
||||
builtin is used to destroy arrays. <B>unset</B> <I>name</I>[<I>subscript</I>]
|
||||
destroys the array element at index <I>subscript</I>.
|
||||
destroys the array element at index <I>subscript</I>,
|
||||
for both indexed and associative arrays.
|
||||
Negative subscripts to indexed arrays are interpreted as described above.
|
||||
Care must be taken to avoid unwanted side effects caused by pathname
|
||||
expansion.
|
||||
Unsetting the last element of an array variable does not unset the variable.
|
||||
<B>unset</B> <I>name</I>, where <I>name</I> is an array, or
|
||||
<B>unset</B> <I>name</I>[<I>subscript</I>], where
|
||||
<I>subscript</I> is <B>*</B> or <B>@</B>, removes the entire array.
|
||||
<P>
|
||||
|
||||
When using a variable name with a subscript as an argument to a command,
|
||||
such as with <B>unset</B>, without using the word expansion syntax
|
||||
described above, the argument is subject to pathname expansion.
|
||||
If pathname expansion is not desired, the argument should be quoted.
|
||||
<P>
|
||||
|
||||
The
|
||||
<B>declare</B>,
|
||||
|
||||
@@ -3413,10 +3492,11 @@ original word are removed unless they have been quoted themselves
|
||||
<P>
|
||||
|
||||
Only brace expansion, word splitting, and pathname expansion
|
||||
can change the number of words of the expansion; other expansions
|
||||
can increase the number of words of the expansion; other expansions
|
||||
expand a single word to a single word.
|
||||
The only exceptions to this are the expansions of
|
||||
"<B>$@</B>" and "<B>${</B><I>name</I><B>[@]}</B>"
|
||||
"<B>$@</B>" and "<B>${</B><I>name</I><B>[@]}</B>",
|
||||
and, in most cases, <B>$*</B> and <B>${</B><I>name</I><B>[*]}</B>
|
||||
as explained above (see
|
||||
<FONT SIZE=-1><B>PARAMETERS</B>).
|
||||
|
||||
@@ -3485,7 +3565,8 @@ Any incorrectly formed brace expansion is left unchanged.
|
||||
A <B>{</B> or <B>,</B> may be quoted with a backslash to prevent its
|
||||
being considered part of a brace expression.
|
||||
To avoid conflicts with parameter expansion, the string <B>${</B>
|
||||
is not considered eligible for brace expansion.
|
||||
is not considered eligible for brace expansion, and inhibits brace
|
||||
expansion until the closing <B>}</B>.
|
||||
<P>
|
||||
|
||||
This construct is typically used as shorthand when the common
|
||||
@@ -3663,6 +3744,8 @@ it introduces a level of variable indirection.
|
||||
expanded and that value is used in the rest of the substitution, rather
|
||||
than the value of <I>parameter</I> itself.
|
||||
This is known as <I>indirect expansion</I>.
|
||||
The value is subject to tilde expansion,
|
||||
parameter expansion, command substitution, and arithmetic expansion.
|
||||
If <I>parameter</I> is a nameref, this expands to the name of the
|
||||
variable referenced by <I>parameter</I> instead of performing the
|
||||
complete indirect expansion.
|
||||
@@ -3848,7 +3931,14 @@ The
|
||||
<I>word</I>
|
||||
|
||||
is expanded to produce a pattern just as in pathname
|
||||
expansion. If the pattern matches the beginning of
|
||||
expansion, and matched against the expanded value of
|
||||
<I>parameter</I>
|
||||
|
||||
using the rules described under
|
||||
<B>Pattern Matching</B>
|
||||
|
||||
below.
|
||||
If the pattern matches the beginning of
|
||||
the value of
|
||||
<I>parameter</I>,
|
||||
|
||||
@@ -3885,7 +3975,13 @@ array in turn, and the expansion is the resultant list.
|
||||
|
||||
<B>Remove matching suffix pattern</B>.
|
||||
The <I>word</I> is expanded to produce a pattern just as in
|
||||
pathname expansion.
|
||||
pathname expansion, and matched against the expanded value of
|
||||
<I>parameter</I>
|
||||
|
||||
using the rules described under
|
||||
<B>Pattern Matching</B>
|
||||
|
||||
below.
|
||||
If the pattern matches a trailing portion of the expanded value of
|
||||
<I>parameter</I>,
|
||||
|
||||
@@ -3919,9 +4015,13 @@ array in turn, and the expansion is the resultant list.
|
||||
<DT>${<I>parameter</I><B>/</B><I>pattern</I><B>/</B><I>string</I>}<DD>
|
||||
<B>Pattern substitution</B>.
|
||||
The <I>pattern</I> is expanded to produce a pattern just as in
|
||||
pathname expansion.
|
||||
pathname expansion,
|
||||
<I>Parameter</I> is expanded and the longest match of <I>pattern</I>
|
||||
against its value is replaced with <I>string</I>.
|
||||
The match is performed using the rules described under
|
||||
<B>Pattern Matching</B>
|
||||
|
||||
below.
|
||||
If <I>pattern</I> begins with <B>/</B>, all matches of <I>pattern</I> are
|
||||
replaced with <I>string</I>. Normally only the first match is replaced.
|
||||
If <I>pattern</I> begins with <B>#</B>, it must match at the beginning
|
||||
@@ -4018,7 +4118,7 @@ format that can be reused as input.
|
||||
|
||||
<DD>
|
||||
The expansion is a string that is the value of <I>parameter</I> with backslash
|
||||
escape sequences expanded as with the <B>$'...'</B> quoting mechansim.
|
||||
escape sequences expanded as with the <B>$'...'</B> quoting mechanism.
|
||||
<DT><B>P</B>
|
||||
|
||||
<DD>
|
||||
@@ -4059,7 +4159,7 @@ is an array variable subscripted with
|
||||
or
|
||||
<B>*</B>,
|
||||
|
||||
the case modification operation is applied to each member of the
|
||||
the operation is applied to each member of the
|
||||
array in turn, and the expansion is the resultant list.
|
||||
<P>
|
||||
The result of the expansion is subject to word splitting and pathname
|
||||
@@ -4354,12 +4454,27 @@ must be matched explicitly, unless the shell option
|
||||
<B>dotglob</B>
|
||||
|
||||
is set.
|
||||
When matching a pathname, the slash character must always be
|
||||
matched explicitly.
|
||||
The filenames
|
||||
<B>``.''</B>
|
||||
|
||||
and
|
||||
<B>``..''</B>
|
||||
|
||||
must always be matched explicitly, even if
|
||||
<B>dotglob</B>
|
||||
|
||||
is set.
|
||||
In other cases, the
|
||||
<B>``.''</B>
|
||||
|
||||
character is not treated specially.
|
||||
When matching a pathname, the slash character must always be
|
||||
matched explicitly by a slash in the pattern, but in other matching
|
||||
contexts it can be matched by a special pattern character as described
|
||||
below under
|
||||
<FONT SIZE=-1><B>Pattern Matching</B>.
|
||||
|
||||
</FONT>
|
||||
See the description of
|
||||
<B>shopt</B>
|
||||
|
||||
@@ -4384,14 +4499,14 @@ The
|
||||
<FONT SIZE=-1><B>GLOBIGNORE</B>
|
||||
|
||||
</FONT>
|
||||
shell variable may be used to restrict the set of filenames matching a
|
||||
shell variable may be used to restrict the set of file names matching a
|
||||
<I>pattern</I>.
|
||||
|
||||
If
|
||||
<FONT SIZE=-1><B>GLOBIGNORE</B>
|
||||
|
||||
</FONT>
|
||||
is set, each matching filename that also matches one of the patterns in
|
||||
is set, each matching file name that also matches one of the patterns in
|
||||
<FONT SIZE=-1><B>GLOBIGNORE</B>
|
||||
|
||||
</FONT>
|
||||
@@ -4613,6 +4728,13 @@ Matches anything except one of the given patterns
|
||||
</DL></DL>
|
||||
|
||||
|
||||
<P>
|
||||
|
||||
Complicated extended pattern matching against long strings is slow,
|
||||
especially when the patterns contain alternations and the strings
|
||||
contain multiple matches.
|
||||
Using separate matches against shorter strings, or using arrays of
|
||||
strings instead of a single long string, may be faster.
|
||||
<A NAME="lbBH"> </A>
|
||||
<H4>Quote Removal</H4>
|
||||
|
||||
@@ -4659,6 +4781,9 @@ than or equal to 10 and assign it to <I>varname</I>.
|
||||
If >&- or <&- is preceded
|
||||
by {<I>varname</I>}, the value of <I>varname</I> defines the file
|
||||
descriptor to close.
|
||||
If {<I>varname</I>} is supplied, the redirection persists beyond
|
||||
the scope of the command, allowing the shell programmer to manage
|
||||
the file descriptor himself.
|
||||
<P>
|
||||
|
||||
In the following descriptions, if the file descriptor number is
|
||||
@@ -5035,7 +5160,7 @@ A variant of here documents, the format is:
|
||||
<P>
|
||||
|
||||
The <I>word</I> undergoes
|
||||
brace expansion, tilde expansion, parameter and variable expansion,
|
||||
tilde expansion, parameter and variable expansion,
|
||||
command substitution, arithmetic expansion, and quote removal.
|
||||
Pathname expansion and word splitting are not performed.
|
||||
The result is supplied as a single string, with a newline appended,
|
||||
@@ -5339,6 +5464,47 @@ Variables local to the function may be declared with the
|
||||
|
||||
builtin command. Ordinarily, variables and their values
|
||||
are shared between the function and its caller.
|
||||
If a variable is declared <B>local</B>, the variable's visible scope
|
||||
is restricted to that function and its children (including the functions
|
||||
it calls).
|
||||
Local variables "shadow" variables with the same name declared at
|
||||
previous scopes.
|
||||
For instance, a local variable declared in a function
|
||||
hides a global variable of the same name: references and assignments
|
||||
refer to the local variable, leaving the global variable unmodified.
|
||||
When the function returns, the global variable is once again visible.
|
||||
<P>
|
||||
|
||||
The shell uses <I>dynamic scoping</I> to control a variable's visibility
|
||||
within functions.
|
||||
With dynamic scoping, visible variables and their values
|
||||
are a result of the sequence of function calls that caused execution
|
||||
to reach the current function.
|
||||
The value of a variable that a function sees depends
|
||||
on its value within its caller, if any, whether that caller is
|
||||
the "global" scope or another shell function.
|
||||
This is also the value that a local variable
|
||||
declaration "shadows", and the value that is restored when the function
|
||||
returns.
|
||||
<P>
|
||||
|
||||
For example, if a variable <I>var</I> is declared as local in function
|
||||
<I>func1</I>, and <I>func1</I> calls another function <I>func2</I>,
|
||||
references to <I>var</I> made from within <I>func2</I> will resolve to the
|
||||
local variable <I>var</I> from <I>func1</I>, shadowing any global variable
|
||||
named <I>var</I>.
|
||||
<P>
|
||||
|
||||
The <B>unset</B> builtin also acts using the same dynamic scope: if a
|
||||
variable is local to the current scope, <B>unset</B> will unset it;
|
||||
otherwise the unset will refer to the variable found in any calling scope
|
||||
as described above.
|
||||
If a variable at the current local scope is unset, it will remain so
|
||||
until it is reset in that scope or until the function returns.
|
||||
Once the function returns, any instance of the variable at a previous
|
||||
scope will become visible.
|
||||
If the unset acts on a variable at a previous scope, any instance of a
|
||||
variable with that name that had been shadowed will become visible.
|
||||
<P>
|
||||
|
||||
The <B>FUNCNEST</B> variable, if set to a numeric value greater
|
||||
@@ -5397,10 +5563,6 @@ the
|
||||
<B>unset</B>
|
||||
|
||||
builtin.
|
||||
Note that shell functions and variables with the same name may result
|
||||
in multiple identically-named entries in the environment passed to the
|
||||
shell's children.
|
||||
Care should be taken in cases where this may cause a problem.
|
||||
<P>
|
||||
|
||||
Functions may be recursive.
|
||||
@@ -5742,6 +5904,17 @@ and
|
||||
<I>arg2</I>
|
||||
|
||||
may be positive or negative integers.
|
||||
When used with the <B>[[</B> command,
|
||||
<I>Arg1</I>
|
||||
|
||||
and
|
||||
<I>Arg2</I>
|
||||
|
||||
are evaluated as arithmetic expressions (see
|
||||
<FONT SIZE=-1><B>ARITHMETIC EVALUATION</B>
|
||||
|
||||
</FONT>
|
||||
above).
|
||||
|
||||
</DL>
|
||||
<A NAME="lbBX"> </A>
|
||||
@@ -5834,9 +6007,10 @@ A full search of the directories in
|
||||
is performed only if the command is not found in the hash table.
|
||||
If the search is unsuccessful, the shell searches for a defined shell
|
||||
function named <B>command_not_found_handle</B>.
|
||||
If that function exists, it is invoked with the original command and
|
||||
If that function exists, it is invoked in a separate execution environment
|
||||
with the original command and
|
||||
the original command's arguments as its arguments, and the function's
|
||||
exit status becomes the exit status of the shell.
|
||||
exit status becomes the exit status of that subshell.
|
||||
If that function is not defined, the shell prints an error
|
||||
message and returns an exit status of 127.
|
||||
<P>
|
||||
@@ -6427,6 +6601,12 @@ command may then be used to inspect their status.
|
||||
If a second attempt to exit is made without an intervening command,
|
||||
the shell does not print another warning, and any stopped
|
||||
jobs are terminated.
|
||||
<P>
|
||||
|
||||
When the shell is waiting for a job or process using the <B>wait</B>
|
||||
builtin, and job control is enabled, <B>wait</B> will return when the
|
||||
job changes state. The <B>-f</B> option will force <B>wait</B> to wait
|
||||
until the job or process terminates before returning.
|
||||
<A NAME="lbCE"> </A>
|
||||
<H3>PROMPTING</H3>
|
||||
|
||||
@@ -6445,11 +6625,20 @@ when it needs more input to complete a command.
|
||||
<B>Bash</B>
|
||||
|
||||
displays
|
||||
<B>PS0</B>
|
||||
<FONT SIZE=-1><B>PS0</B>
|
||||
|
||||
</FONT>
|
||||
after it reads a command but before executing it.
|
||||
<B>Bash</B>
|
||||
|
||||
displays
|
||||
<FONT SIZE=-1><B>PS4</B>
|
||||
|
||||
</FONT>
|
||||
as described above
|
||||
before tracing each command when the <B>-x</B> option is enabled.
|
||||
<B>Bash</B>
|
||||
|
||||
allows these prompt strings to be customized by inserting a number of
|
||||
backslash-escaped special characters that are decoded as follows:
|
||||
<DL COMPACT><DT><DD>
|
||||
@@ -7134,6 +7323,17 @@ can be set to either
|
||||
or
|
||||
<B>vi</B>.
|
||||
|
||||
<DT><B>emacs-mode-string (@)</B>
|
||||
|
||||
<DD>
|
||||
If the <I>show-mode-in-prompt</I> variable is enabled,
|
||||
this string is displayed immediately before the last line of the primary
|
||||
prompt when emacs editing mode is active. The value is expanded like a
|
||||
key binding, so the standard set of meta- and control prefixes and
|
||||
backslash escape sequences is available.
|
||||
Use the \1 and \2 escapes to begin and end sequences of
|
||||
non-printing characters, which can be used to embed a terminal control
|
||||
sequence into the mode string.
|
||||
<DT><B>enable-bracketed-paste (Off)</B>
|
||||
|
||||
<DD>
|
||||
@@ -7217,16 +7417,6 @@ the value of
|
||||
<B>editing-mode</B>
|
||||
|
||||
also affects the default keymap.
|
||||
<DT><B>emacs-mode-string (@)</B>
|
||||
|
||||
<DD>
|
||||
This string is displayed immediately before the last line of the primary
|
||||
prompt when emacs editing mode is active. The value is expanded like a
|
||||
key binding, so the standard set of meta- and control prefixes and
|
||||
backslash escape sequences is available.
|
||||
Use the \1 and \2 escapes to begin and end sequences of
|
||||
non-printing characters, which can be used to embed a terminal control
|
||||
sequence into the mode string.
|
||||
<DT><B>keyseq-timeout (500)</B>
|
||||
|
||||
<DD>
|
||||
@@ -7320,9 +7510,9 @@ of ringing the bell.
|
||||
<DT><B>show-mode-in-prompt (Off)</B>
|
||||
|
||||
<DD>
|
||||
If set to <B>On</B>, add a character to the beginning of the prompt
|
||||
indicating the editing mode: emacs (@), vi command (:) or vi
|
||||
insertion (+).
|
||||
If set to <B>On</B>, add a string to the beginning of the prompt
|
||||
indicating the editing mode: emacs, vi command, or vi insertion.
|
||||
The mode strings are user-settable (e.g., <I>emacs-mode-string</I>).
|
||||
<DT><B>skip-completed-text (Off)</B>
|
||||
|
||||
<DD>
|
||||
@@ -7335,7 +7525,8 @@ following the cursor are not duplicated.
|
||||
<DT><B>vi-cmd-mode-string ((cmd))</B>
|
||||
|
||||
<DD>
|
||||
This string is displayed immediately before the last line of the primary
|
||||
If the <I>show-mode-in-prompt</I> variable is enabled,
|
||||
this string is displayed immediately before the last line of the primary
|
||||
prompt when vi editing mode is active and in command mode.
|
||||
The value is expanded like a
|
||||
key binding, so the standard set of meta- and control prefixes and
|
||||
@@ -7346,7 +7537,8 @@ sequence into the mode string.
|
||||
<DT><B>vi-ins-mode-string ((ins))</B>
|
||||
|
||||
<DD>
|
||||
This string is displayed immediately before the last line of the primary
|
||||
If the <I>show-mode-in-prompt</I> variable is enabled,
|
||||
this string is displayed immediately before the last line of the primary
|
||||
prompt when vi editing mode is active and in insertion mode.
|
||||
The value is expanded like a
|
||||
key binding, so the standard set of meta- and control prefixes and
|
||||
@@ -7378,8 +7570,9 @@ The
|
||||
|
||||
construct allows bindings to be made based on the
|
||||
editing mode, the terminal being used, or the application using
|
||||
readline. The text of the test extends to the end of the line;
|
||||
no characters are required to isolate it.
|
||||
readline. The text of the test, after any comparison operator,
|
||||
<BR> extends to the end of the line;
|
||||
unless otherwise noted, no characters are required to isolate it.
|
||||
<DL COMPACT><DT><DD>
|
||||
<DL COMPACT>
|
||||
<DT><B>mode</B><DD>
|
||||
@@ -7406,6 +7599,33 @@ and
|
||||
<I>sun-cmd</I>,
|
||||
|
||||
for instance.
|
||||
<DT><B>version</B><DD>
|
||||
The <B>version</B> test may be used to perform comparisons against
|
||||
specific readline versions.
|
||||
The <B>version</B> expands to the current readline version.
|
||||
The set of comparison operators includes
|
||||
<B>=</B>,
|
||||
|
||||
(and
|
||||
<B>==</B>),
|
||||
|
||||
<B>!=</B>,
|
||||
|
||||
<B><=</B>,
|
||||
|
||||
<B>>=</B>,
|
||||
|
||||
<B><</B>,
|
||||
|
||||
and
|
||||
<B>></B>.
|
||||
|
||||
The version number supplied on the right side of the operator consists
|
||||
of a major version number, an optional decimal point, and an optional
|
||||
minor version (e.g., <B>7.1</B>). If the minor version is omitted, it
|
||||
is assumed to be <B>0</B>.
|
||||
The operator may be separated from the string <B>version</B>
|
||||
and from the version number argument by whitespace.
|
||||
<DT><B>application</B><DD>
|
||||
The <B>application</B> construct is used to include
|
||||
application-specific settings. Each program using the readline
|
||||
@@ -7425,6 +7645,15 @@ key sequence that quotes the current or previous word in <B>bash</B>:
|
||||
|
||||
</DL>
|
||||
|
||||
<DT><I>variable</I><DD>
|
||||
The <I>variable</I> construct provides simple equality tests for readline
|
||||
variables and values.
|
||||
The permitted comparison operators are <I>=</I>, <I>==</I>, and <I>!=</I>.
|
||||
The variable name must be separated from the comparison operator by
|
||||
whitespace; the operator may be separated from the value on the right hand
|
||||
side by whitespace.
|
||||
Both string and boolean variables may be tested. Boolean variables must be
|
||||
tested against the values <I>on</I> and <I>off</I>.
|
||||
</DL></DL>
|
||||
|
||||
<DT><B>$endif</B><DD>
|
||||
@@ -7554,6 +7783,21 @@ Words are delimited by non-quoted shell metacharacters.
|
||||
<DD>
|
||||
Move back to the start of the current or previous word.
|
||||
Words are delimited by non-quoted shell metacharacters.
|
||||
<DT><B>previous-screen-line</B>
|
||||
|
||||
<DD>
|
||||
Attempt to move point to the same physical screen column on the previous
|
||||
physical screen line. This will not have the desired effect if the current
|
||||
Readline line does not take up more than one physical line or if point is not
|
||||
greater than the length of the prompt plus the screen width.
|
||||
<DT><B>next-screen-line</B>
|
||||
|
||||
<DD>
|
||||
Attempt to move point to the same physical screen column on the next
|
||||
physical screen line. This will not have the desired effect if the current
|
||||
Readline line does not take up more than one physical line or if the length
|
||||
of the current Readline line is not greater than the length of the prompt
|
||||
plus the screen width.
|
||||
<DT><B>clear-screen (C-l)</B>
|
||||
|
||||
<DD>
|
||||
@@ -7634,6 +7878,21 @@ This is a non-incremental search.
|
||||
Search backward through the history for the string of characters
|
||||
between the start of the current line and the point.
|
||||
This is a non-incremental search.
|
||||
<DT><B>history-substring-search-backward</B>
|
||||
|
||||
<DD>
|
||||
Search backward through the history for the string of characters
|
||||
between the start of the current line and the current cursor
|
||||
position (the <I>point</I>).
|
||||
The search string may match anywhere in a history line.
|
||||
This is a non-incremental search.
|
||||
<DT><B>history-substring-search-forward</B>
|
||||
|
||||
<DD>
|
||||
Search forward through the history for the string of characters
|
||||
between the start of the current line and the point.
|
||||
The search string may match anywhere in a history line.
|
||||
This is a non-incremental search.
|
||||
<DT><B>yank-nth-arg (M-C-y)</B>
|
||||
|
||||
<DD>
|
||||
@@ -7710,9 +7969,10 @@ A synonym for <B>yank-last-arg</B>.
|
||||
|
||||
<DD>
|
||||
Accept the current line for execution and fetch the next line
|
||||
relative to the current line from the history for editing. Any
|
||||
argument is ignored.
|
||||
<DT><B>edit-and-execute-command (C-xC-e)</B>
|
||||
relative to the current line from the history for editing.
|
||||
A numeric argument, if supplied, specifies the history entry to use instead
|
||||
of the current line.
|
||||
<DT><B>edit-and-execute-command (C-x C-e)</B>
|
||||
|
||||
<DD>
|
||||
Invoke an editor on the current command line, and execute the result as shell
|
||||
@@ -8124,11 +8384,12 @@ Abort the current editing command and
|
||||
ring the terminal's bell (subject to the setting of
|
||||
<B>bell-style</B>).
|
||||
|
||||
<DT><B>do-uppercase-version (M-a, M-b, M-</B><I>x</I>, ...)
|
||||
<DT><B>do-lowercase-version (M-A, M-B, M-</B><I>x</I>, ...)
|
||||
|
||||
<DD>
|
||||
If the metafied character <I>x</I> is lowercase, run the command
|
||||
that is bound to the corresponding uppercase character.
|
||||
If the metafied character <I>x</I> is uppercase, run the command
|
||||
that is bound to the corresponding metafied lowercase character.
|
||||
The behavior is undefined if <I>x</I> is already lowercase.
|
||||
<DT><B>prefix-meta (ESC)</B>
|
||||
|
||||
<DD>
|
||||
@@ -8542,7 +8803,7 @@ If <B>HISTFILESIZE</B> is unset, or set to null, a non-numeric value,
|
||||
or a numeric value less than zero, the history file is not truncated.
|
||||
When the history file is read,
|
||||
lines beginning with the history comment character followed immediately
|
||||
by a digit are interpreted as timestamps for the preceding history line.
|
||||
by a digit are interpreted as timestamps for the following history line.
|
||||
These timestamps are optionally displayed depending on the value of the
|
||||
<FONT SIZE=-1><B>HISTTIMEFORMAT</B>
|
||||
|
||||
@@ -8652,7 +8913,7 @@ for information on setting and unsetting shell options.
|
||||
|
||||
The shell supports a history expansion feature that
|
||||
is similar to the history expansion in
|
||||
<B>csh.</B>
|
||||
<B>csh</B>.
|
||||
|
||||
This section describes what syntax features are available. This
|
||||
feature is enabled by default for interactive shells, and can be
|
||||
@@ -8677,7 +8938,9 @@ fix errors in previous commands quickly.
|
||||
<P>
|
||||
|
||||
History expansion is performed immediately after a complete line
|
||||
is read, before the shell breaks it into words.
|
||||
is read, before the shell breaks it into words, and is performed
|
||||
on each line individually without taking quoting on previous lines into
|
||||
account.
|
||||
It takes place in two parts.
|
||||
The first is to determine which line from the history list
|
||||
to use during substitution.
|
||||
@@ -9035,7 +9298,7 @@ accepts
|
||||
<B>--</B>
|
||||
|
||||
to signify the end of the options.
|
||||
The <B>:</B>, <B>true</B>, <B>false</B>, and <B>test</B> builtins
|
||||
The <B>:</B>, <B>true</B>, <B>false</B>, and <B>test</B>/<B>[</B> builtins
|
||||
do not accept options and do not treat <B>--</B> specially.
|
||||
The <B>exit</B>, <B>logout</B>, <B>return</B>,
|
||||
<B>break</B>, <B>continue</B>, <B>let</B>,
|
||||
@@ -9705,6 +9968,13 @@ The <I>wordlist</I> is split using the characters in the
|
||||
|
||||
</FONT>
|
||||
special variable as delimiters, and each resultant word is expanded.
|
||||
Shell quoting is honored within <I>wordlist</I>,
|
||||
in order to provide a
|
||||
mechanism for the words to contain shell metacharacters or characters
|
||||
in the value of
|
||||
<FONT SIZE=-1><B>IFS</B>.
|
||||
|
||||
</FONT>
|
||||
The possible completions are the members of the resultant list which
|
||||
match the word being completed.
|
||||
<DT><B>-X</B> <I>filterpat</I><DD>
|
||||
@@ -10209,6 +10479,7 @@ unless the
|
||||
shell option
|
||||
is enabled. In that case, it returns failure.
|
||||
An interactive shell returns failure if the file cannot be executed.
|
||||
A subshell exits unconditionally if <B>exec</B> fails.
|
||||
If
|
||||
<I>command</I>
|
||||
|
||||
@@ -10292,7 +10563,7 @@ where a negative number is used as an offset from the current
|
||||
command number). If
|
||||
<I>last</I>
|
||||
|
||||
is not specified it is set to
|
||||
is not specified, it is set to
|
||||
the current command for listing (so that
|
||||
|
||||
<TT>fc -l -10</TT>
|
||||
@@ -10303,7 +10574,7 @@ otherwise.
|
||||
If
|
||||
<I>first</I>
|
||||
|
||||
is not specified it is set to the previous
|
||||
is not specified, it is set to the previous
|
||||
command for editing and -16 for listing.
|
||||
<P>
|
||||
The
|
||||
@@ -10349,7 +10620,7 @@ echoed and executed.
|
||||
<P>
|
||||
In the second form, <I>command</I> is re-executed after each instance
|
||||
of <I>pat</I> is replaced by <I>rep</I>.
|
||||
<I>Command</I> is intepreted the same as <I>first</I> above.
|
||||
<I>Command</I> is interpreted the same as <I>first</I> above.
|
||||
A useful alias to use with this is
|
||||
|
||||
<TT>r='fc -s'</TT>,
|
||||
@@ -10621,6 +10892,7 @@ The return status is 0 unless no command matches
|
||||
|
||||
<DT><B>history</B> <B>-c</B><DD>
|
||||
<DT><B>history -d</B> <I>offset</I><DD>
|
||||
<DT><B>history -d</B> <I>start</I>-<I>end</I><DD>
|
||||
<DT><B>history</B> <B>-anrw</B> [<I>filename</I>]<DD>
|
||||
<DT><B>history</B> <B>-p</B> <I>arg</I> [<I>arg ...</I>]<DD>
|
||||
<DT><B>history</B> <B>-s</B> <I>arg</I> [<I>arg ...</I>]<DD>
|
||||
@@ -10661,6 +10933,14 @@ is used. Options, if supplied, have the following meanings:
|
||||
Clear the history list by deleting all the entries.
|
||||
<DT><B>-d</B> <I>offset</I><DD>
|
||||
Delete the history entry at position <I>offset</I>.
|
||||
If <I>offset</I> 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 refers to the current
|
||||
<B>history -d</B> command.
|
||||
<DT><B>-d</B> <I>start</I>-<I>end</I><DD>
|
||||
Delete the history entries between positions <I>start</I> and <I>end</I>,
|
||||
inclusive. Positive and negative values for <I>start</I> and <I>end</I>
|
||||
are interpreted as described above.
|
||||
<DT><B>-a</B>
|
||||
|
||||
<DD>
|
||||
@@ -10935,6 +11215,8 @@ Options, if supplied, have the following meanings:
|
||||
<DD>
|
||||
The first character of <I>delim</I> is used to terminate each input line,
|
||||
rather than newline.
|
||||
If <I>delim</I> is the empty string, <B>mapfile</B> will terminate a line
|
||||
when it reads a NUL character.
|
||||
<DT><B>-n</B>
|
||||
|
||||
<DD>
|
||||
@@ -11250,6 +11532,8 @@ Other <I>name</I> arguments are ignored.
|
||||
<DD>
|
||||
The first character of <I>delim</I> is used to terminate the input line,
|
||||
rather than newline.
|
||||
If <I>delim</I> is the empty string, <B>read</B> will terminate a line
|
||||
when it reads a NUL character.
|
||||
<DT><B>-e</B>
|
||||
|
||||
<DD>
|
||||
@@ -11263,7 +11547,7 @@ is coming from a terminal,
|
||||
</FONT>
|
||||
above) is used to obtain the line.
|
||||
Readline uses the current (or default, if line editing was not previously
|
||||
active) editing settings.
|
||||
active) editing settings, but uses Readline's default filename completion.
|
||||
<DT><B>-i </B><I>text</I>
|
||||
|
||||
<DD>
|
||||
@@ -11409,7 +11693,7 @@ is omitted, the return status is that of the last command
|
||||
executed in the function body.
|
||||
If <B>return</B> is executed by a trap handler, the last command used to
|
||||
determine the status is the last command executed before the trap handler.
|
||||
if <B>return</B> is executed during a <B>DEBUG</B> trap, the last command
|
||||
If <B>return</B> is executed during a <B>DEBUG</B> trap, the last command
|
||||
used to determine the status is the last command executed by the trap
|
||||
handler before <B>return</B> was invoked.
|
||||
If
|
||||
@@ -11970,7 +12254,8 @@ With no options, or with the
|
||||
<B>-p</B>
|
||||
|
||||
option, a list of all settable options is displayed, with
|
||||
an indication of whether or not each is set.
|
||||
an indication of whether or not each is set;
|
||||
if <I>optnames</I> are supplied, the output is restricted to those options.
|
||||
The <B>-p</B> option causes output to be displayed in a form that
|
||||
may be reused as input.
|
||||
Other options have the following meanings:
|
||||
@@ -12035,6 +12320,12 @@ The list of <B>shopt</B> options is:
|
||||
|
||||
|
||||
<DL COMPACT>
|
||||
<DT><B>assoc_expand_once</B>
|
||||
|
||||
<DD>
|
||||
If set, the shell suppresses multiple evaluation of associative array
|
||||
subscripts during arithmetic expression evaluation and while executing
|
||||
builtins that can perform variable assignments.
|
||||
<DT><B>autocd</B>
|
||||
|
||||
<DD>
|
||||
@@ -12083,8 +12374,8 @@ postpones exiting if any jobs are stopped.
|
||||
<DT><B>checkwinsize</B>
|
||||
|
||||
<DD>
|
||||
If set, <B>bash</B> checks the window size after each command
|
||||
and, if necessary, updates the values of
|
||||
If set, <B>bash</B> checks the window size after each external (non-builtin)
|
||||
command and, if necessary, updates the values of
|
||||
<FONT SIZE=-1><B>LINES</B>
|
||||
|
||||
</FONT>
|
||||
@@ -12101,6 +12392,11 @@ If set,
|
||||
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
|
||||
<FONT SIZE=-1><B>HISTORY</B>.
|
||||
|
||||
</FONT>
|
||||
<DT><B>compat31</B>
|
||||
|
||||
<DD>
|
||||
@@ -12175,6 +12471,14 @@ to make them fatal errors that cause the shell to exit),
|
||||
and does not reset the
|
||||
loop state when a shell function is executed (this allows <B>break</B> or
|
||||
<B>continue</B> in a shell function to affect loops in the caller's context).
|
||||
<DT><B>compat44</B>
|
||||
|
||||
<DD>
|
||||
If set,
|
||||
<B>bash</B>
|
||||
|
||||
saves the positional parameters to BASH_ARGV and BASH_ARGC before they are
|
||||
used, regardless of whether or not extended debugging mode is enabled.
|
||||
<DT><B>complete_fullquote</B>
|
||||
|
||||
<DD>
|
||||
@@ -12226,6 +12530,16 @@ If set,
|
||||
|
||||
includes filenames beginning with a `.' in the results of pathname
|
||||
expansion.
|
||||
The filenames
|
||||
<B>``.''</B>
|
||||
|
||||
and
|
||||
<B>``..''</B>
|
||||
|
||||
must always be matched explicitly, even if
|
||||
<B>dotglob</B>
|
||||
|
||||
is set.
|
||||
<DT><B>execfail</B>
|
||||
|
||||
<DD>
|
||||
@@ -12441,6 +12755,12 @@ If set, and the
|
||||
|
||||
option is enabled, multi-line commands are saved to the history with
|
||||
embedded newlines rather than using semicolon separators where possible.
|
||||
<DT><B>localvar_inherit</B>
|
||||
|
||||
<DD>
|
||||
If set, local variables inherit the value and attributes of a variable of
|
||||
the same name that exists at a previous scope before any new value is
|
||||
assigned. The nameref attribute is not inherited.
|
||||
<DT><B>login_shell</B>
|
||||
|
||||
<DD>
|
||||
@@ -13221,22 +13541,25 @@ subsequently reset. The exit status is true unless a
|
||||
<I>name</I>
|
||||
|
||||
is readonly.
|
||||
<DT><B>wait</B> [<B>-n</B>] [<I>n ...</I>]<DD>
|
||||
<DT><B>wait</B> [<B>-fn</B>] [<I>id ...</I>]<DD>
|
||||
Wait for each specified child process and return its termination status.
|
||||
Each
|
||||
<I>n</I>
|
||||
<I>id</I>
|
||||
|
||||
may be a process
|
||||
ID or a job specification; if a job spec is given, all processes
|
||||
in that job's pipeline are waited for. If
|
||||
<I>n</I>
|
||||
<I>id</I>
|
||||
|
||||
is not given, all currently active child processes
|
||||
are waited for, and the return status is zero.
|
||||
If the <B>-n</B> option is supplied, <B>wait</B> waits for any job to
|
||||
terminate and returns its exit status.
|
||||
If the <B>-f</B> option is supplied, and job control is enabled,
|
||||
<B>wait</B> forces <I>id</I> to terminate before returning its status,
|
||||
instead of returning when it changes status.
|
||||
If
|
||||
<I>n</I>
|
||||
<I>id</I>
|
||||
|
||||
specifies a non-existent process or job, the return status is
|
||||
127. Otherwise, the return status is the exit status of the last
|
||||
@@ -13529,7 +13852,7 @@ There may be only one active coprocess at a time.
|
||||
<HR>
|
||||
<TABLE WIDTH=100%>
|
||||
<TR>
|
||||
<TH ALIGN=LEFT width=33%>GNU Bash 4.4<TH ALIGN=CENTER width=33%>2016 August 26<TH ALIGN=RIGHT width=33%>BASH(1)
|
||||
<TH ALIGN=LEFT width=33%>GNU Bash 5.0<TH ALIGN=CENTER width=33%>2018 March 15<TH ALIGN=RIGHT width=33%>BASH(1)
|
||||
</TR>
|
||||
</TABLE>
|
||||
<HR>
|
||||
@@ -13635,6 +13958,6 @@ There may be only one active coprocess at a time.
|
||||
</DL>
|
||||
<HR>
|
||||
This document was created by man2html from bash.1.<BR>
|
||||
Time: 31 August 2016 10:24:30 EDT
|
||||
Time: 19 March 2018 09:43:32 EDT
|
||||
</BODY>
|
||||
</HTML>
|
||||
|
||||
Reference in New Issue
Block a user