Use zsh syntax in code blocks
This commit is contained in:
Jeffrey Serio
parent
e3ddbae998
commit
4faab81391
@ -107,5 +107,11 @@ system("rm -rf $cwd/zsh_manual/src") == 0 or die "$?";
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mkdir("$cwd/zsh_manual/src") or die "$?";
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system("cp $mdbook_src_dir/* $cwd/zsh_manual/src/") == 0 or die "$?";
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# Replace ``` example with ```zsh for syntax highlighting
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@files = <$cwd/zsh_manual/src/*.md>;
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foreach my $file (@files) {
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system("sed -i 's/``` example/```zsh/g' '$file'") == 0 or die "$?";
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}
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# Cleanup zsh_doc_tmp
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system("rm -rf $zsh_doc_tmp_dir") == 0 or die "$?";
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@ -6,40 +6,39 @@
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<!-- END doctoc generated TOC please keep comment here to allow auto update -->
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<span id="Arithmetic-Evaluation"></span>
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<span id="Arithmetic-Evaluation-1"></span>
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<span id="Arithmetic-Evaluation"></span> <span
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id="Arithmetic-Evaluation-1"></span>
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# 11 Arithmetic Evaluation
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<span id="index-arithmetic-evaluation"></span>
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<span id="index-evaluation_002c-arithmetic"></span>
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<span id="index-let_002c-use-of"></span>
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<span id="index-arithmetic-evaluation"></span> <span
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id="index-evaluation_002c-arithmetic"></span> <span
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id="index-let_002c-use-of"></span>
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The shell can perform integer and floating point arithmetic, either
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using the builtin `let`, or via a substitution of the form
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`$((``...``))`. For integers, the shell is usually compiled to use
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8-byte precision where this is available, otherwise precision is 4
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bytes. This can be tested, for example, by giving the command ‘`print -
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$(( 12345678901 ))`’; if the number appears unchanged, the precision is
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at least 8 bytes. Floating point arithmetic always uses the ‘double’
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type with whatever corresponding precision is provided by the compiler
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and the library.
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using the builtin let, or via a substitution of the form $((`...`)). For
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integers, the shell is usually compiled to use 8-byte precision where
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this is available, otherwise precision is 4 bytes. This can be tested,
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for example, by giving the command ‘print - $(( 12345678901 ))’; if the
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number appears unchanged, the precision is at least 8 bytes. Floating
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point arithmetic always uses the ‘double’ type with whatever
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corresponding precision is provided by the compiler and the library.
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The `let` builtin command takes arithmetic expressions as arguments;
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each is evaluated separately. Since many of the arithmetic operators, as
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well as spaces, require quoting, an alternative form is provided: for
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any command which begins with a ‘`((`’, all the characters until a
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matching ‘`))`’ are treated as a quoted expression and arithmetic
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expansion performed as for an argument of `let`. More precisely,
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‘`((``...``))`’ is equivalent to ‘`let "``...``"`’. The return status
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is 0 if the arithmetic value of the expression is non-zero, 1 if it is
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zero, and 2 if an error occurred.
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The let builtin command takes arithmetic expressions as arguments; each
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is evaluated separately. Since many of the arithmetic operators, as well
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as spaces, require quoting, an alternative form is provided: for any
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command which begins with a ‘((’, all the characters until a matching
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‘))’ are treated as a double-quoted expression and arithmetic expansion
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performed as for an argument of let. More precisely, ‘((`...`))’ is
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equivalent to ‘let "`...`"’. The return status is 0 if the arithmetic
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value of the expression is non-zero, 1 if it is zero, and 2 if an error
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occurred.
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For example, the following statement
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<div class="example">
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``` example
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```zsh
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(( val = 2 + 1 ))
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```
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@ -49,39 +48,38 @@ is equivalent to
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<div class="example">
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``` example
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```zsh
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let "val = 2 + 1"
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```
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</div>
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both assigning the value 3 to the shell variable `val` and returning a
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both assigning the value 3 to the shell variable val and returning a
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zero status.
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<span id="index-arithmetic-base"></span>
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<span id="index-bases_002c-in-arithmetic"></span>
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<span id="index-arithmetic-base"></span> <span
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id="index-bases_002c-in-arithmetic"></span>
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Integers can be in bases other than 10. A leading ‘`0x`’ or ‘`0X`’
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denotes hexadecimal and a leading ‘`0b`’ or ‘`0B`’ binary. Integers may
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also be of the form ‘`base``#``n`’, where `base` is a decimal number
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between two and thirty-six representing the arithmetic base and `n` is a
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number in that base (for example, ‘`16#ff`’ is 255 in hexadecimal). The
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`base``#` may also be omitted, in which case base 10 is used. For
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backwards compatibility the form ‘`[``base``]``n`’ is also accepted.
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Integers can be in bases other than 10. A leading ‘0x’ or ‘0X’ denotes
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hexadecimal and a leading ‘0b’ or ‘0B’ binary. Integers may also be of
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the form ‘`base`#`n`’, where `base` is a decimal number between two and
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thirty-six representing the arithmetic base and `n` is a number in that
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base (for example, ‘16#ff’ is 255 in hexadecimal). The `base`# may also
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be omitted, in which case base 10 is used. For backwards compatibility
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the form ‘\[`base`\]`n`’ is also accepted.
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An integer expression or a base given in the form ‘`base``#``n`’ may
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contain underscores (‘`_`’) after the leading digit for visual guidance;
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these are ignored in computation. Examples are `1_000_000` or
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`0xffff_ffff` which are equivalent to `1000000` and `0xffffffff`
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respectively.
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An integer expression or a base given in the form ‘`base`#`n`’ may
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contain underscores (‘\_’) after the leading digit for visual guidance;
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these are ignored in computation. Examples are 1_000_000 or 0xffff_ffff
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which are equivalent to 1000000 and 0xffffffff respectively.
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It is also possible to specify a base to be used for output in the form
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‘`[#``base``]`’, for example ‘`[#16]`’. This is used when outputting
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‘\[#`base`\]’, for example ‘\[#16\]’. This is used when outputting
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arithmetical substitutions or when assigning to scalar parameters, but
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an explicitly defined integer or floating point parameter will not be
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affected. If an integer variable is implicitly defined by an arithmetic
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expression, any base specified in this way will be set as the variable’s
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output arithmetic base as if the option ‘`-i` `base`’ to the `typeset`
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output arithmetic base as if the option ‘-i `base`’ to the typeset
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builtin had been used. The expression has no precedence and if it occurs
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more than once in a mathematical expression, the last encountered is
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used. For clarity it is recommended that it appear at the beginning of
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@ -89,7 +87,7 @@ an expression. As an example:
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<div class="example">
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``` example
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```zsh
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typeset -i 16 y
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print $(( [#8] x = 32, y = 32 ))
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print $x $y
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@ -97,11 +95,10 @@ print $x $y
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</div>
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outputs first ‘`8#40`’, the rightmost value in the given output base,
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and then ‘`8#40 16#20`’, because `y` has been explicitly declared to
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have output base 16, while `x` (assuming it does not already exist) is
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implicitly typed by the arithmetic evaluation, where it acquires the
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output base 8.
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outputs first ‘8#40’, the rightmost value in the given output base, and
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then ‘8#40 16#20’, because y has been explicitly declared to have output
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base 16, while x (assuming it does not already exist) is implicitly
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typed by the arithmetic evaluation, where it acquires the output base 8.
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The `base` may be replaced or followed by an underscore, which may
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itself be followed by a positive integer (if it is missing the value 3
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@ -111,14 +108,14 @@ integer specifies the number of digits to group together. For example:
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<div class="example">
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``` example
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```zsh
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setopt cbases
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print $(( [#16_4] 65536 ** 2 ))
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```
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</div>
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outputs ‘`0x1_0000_0000`’.
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outputs ‘0x1_0000_0000’.
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The feature can be used with floating point numbers, in which case the
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base must be omitted; grouping is away from the decimal point. For
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@ -126,40 +123,40 @@ example,
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<div class="example">
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``` example
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```zsh
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zmodload zsh/mathfunc
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print $(( [#_] sqrt(1e7) ))
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```
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</div>
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outputs ‘`3_162.277_660_168_379_5`’ (the number of decimal places shown
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outputs ‘3_162.277_660_168_379_5’ (the number of decimal places shown
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may vary).
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<span id="index-C_005fBASES_002c-use-of"></span>
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<span id="index-OCTAL_005fZEROES_002c-use-of"></span>
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<span id="index-C_005fBASES_002c-use-of"></span> <span
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id="index-OCTAL_005fZEROES_002c-use-of"></span>
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If the `C_BASES` option is set, hexadecimal numbers are output in the
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standard C format, for example ‘`0xFF`’ instead of the usual ‘`16#FF`’.
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If the option `OCTAL_ZEROES` is also set (it is not by default), octal
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numbers will be treated similarly and hence appear as ‘`077`’ instead of
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‘`8#77`’. This option has no effect on the output of bases other than
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If the C_BASES option is set, hexadecimal numbers are output in the
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standard C format, for example ‘0xFF’ instead of the usual ‘16#FF’. If
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the option OCTAL_ZEROES is also set (it is not by default), octal
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numbers will be treated similarly and hence appear as ‘077’ instead of
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‘8#77’. This option has no effect on the output of bases other than
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hexadecimal and octal, and these formats are always understood on input.
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When an output base is specified using the ‘`[#``base``]`’ syntax, an
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When an output base is specified using the ‘\[#`base`\]’ syntax, an
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appropriate base prefix will be output if necessary, so that the value
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output is valid syntax for input. If the `#` is doubled, for example
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‘`[##16]`’, then no base prefix is output.
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output is valid syntax for input. If the # is doubled, for example
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‘\[##16\]’, then no base prefix is output.
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Floating point constants are recognized by the presence of a decimal
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point or an exponent. The decimal point may be the first character of
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the constant, but the exponent character `e` or `E` may not, as it will
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be taken for a parameter name. All numeric parts (before and after the
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the constant, but the exponent character e or E may not, as it will be
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taken for a parameter name. All numeric parts (before and after the
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decimal point and in the exponent) may contain underscores after the
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leading digit for visual guidance; these are ignored in computation.
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<span id="index-arithmetic-operators"></span>
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<span id="index-operators_002c-arithmetic"></span>
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<span id="index-arithmetic-operators"></span> <span
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id="index-operators_002c-arithmetic"></span>
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An arithmetic expression uses nearly the same syntax and associativity
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of expressions as in C.
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@ -167,132 +164,132 @@ of expressions as in C.
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In the native mode of operation, the following operators are supported
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(listed in decreasing order of precedence):
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- `+ - ! ~ ++ –`
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unary plus/minus, logical NOT, complement, {pre,post}{in,de}crement
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\+ - ! \~ ++ –
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unary plus/minus, logical NOT, complement, {pre,post}{in,de}crement
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- `<< >>`
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bitwise shift left, right
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\<\< >\>
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bitwise shift left, right
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- `&`
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bitwise AND
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&
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bitwise AND
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- `^`
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bitwise XOR
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^
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bitwise XOR
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- `|`
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bitwise OR
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\|
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bitwise OR
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- `**`
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exponentiation
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\*\*
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exponentiation
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- `* / %`
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multiplication, division, modulus (remainder)
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\* / %
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multiplication, division, modulus (remainder)
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- `+ -`
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addition, subtraction
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\+ -
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addition, subtraction
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- `< > <= >=`
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comparison
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\< > \<= >=
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comparison
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- `== !=`
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equality and inequality
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== !=
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equality and inequality
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- `&&`
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logical AND
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&&
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logical AND
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- `|| ^^`
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logical OR, XOR
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\|\| ^^
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logical OR, XOR
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- `? :`
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ternary operator
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? :
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ternary operator
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- `= += -= *= /= %= &= ^= |= <<= >>= &&= ||= ^^= **=`
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assignment
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= += -= \*= /= %= &= ^= \|= \<\<= >\>= &&= \|\|= ^^= \*\*=
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assignment
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- `,`
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comma operator
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,
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comma operator
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The operators ‘`&&`’, ‘`||`’, ‘`&&=`’, and ‘`||=`’ are short-circuiting,
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and only one of the latter two expressions in a ternary operator is
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The operators ‘&&’, ‘\|\|’, ‘&&=’, and ‘\|\|=’ are short-circuiting, and
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only one of the latter two expressions in a ternary operator is
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evaluated. Note the precedence of the bitwise AND, OR, and XOR
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operators.
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With the option `C_PRECEDENCES` the precedences (but no other
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properties) of the operators are altered to be the same as those in most
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other languages that support the relevant operators:
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With the option C_PRECEDENCES the precedences (but no other properties)
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of the operators are altered to be the same as those in most other
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languages that support the relevant operators:
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- `+ - ! ~ ++ –`
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unary plus/minus, logical NOT, complement, {pre,post}{in,de}crement
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\+ - ! \~ ++ –
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unary plus/minus, logical NOT, complement, {pre,post}{in,de}crement
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- `**`
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exponentiation
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\*\*
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exponentiation
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- `* / %`
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multiplication, division, modulus (remainder)
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\* / %
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multiplication, division, modulus (remainder)
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- `+ -`
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addition, subtraction
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\+ -
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addition, subtraction
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- `<< >>`
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bitwise shift left, right
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\<\< >\>
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bitwise shift left, right
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- `< > <= >=`
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comparison
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\< > \<= >=
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comparison
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- `== !=`
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equality and inequality
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== !=
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equality and inequality
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- `&`
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bitwise AND
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&
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bitwise AND
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- `^`
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bitwise XOR
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^
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bitwise XOR
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- `|`
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bitwise OR
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\|
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bitwise OR
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- `&&`
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logical AND
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&&
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logical AND
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- `^^`
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logical XOR
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^^
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logical XOR
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- `||`
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logical OR
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\|\|
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logical OR
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- `? :`
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ternary operator
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? :
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ternary operator
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- `= += -= *= /= %= &= ^= |= <<= >>= &&= ||= ^^= **=`
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assignment
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= += -= \*= /= %= &= ^= \|= \<\<= >\>= &&= \|\|= ^^= \*\*=
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assignment
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- `,`
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comma operator
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,
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comma operator
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Note the precedence of exponentiation in both cases is below that of
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unary operators, hence ‘`-3**2`’ evaluates as ‘`9`’, not ‘`-9`’. Use
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parentheses where necessary: ‘`-(3**2)`’. This is for compatibility with
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unary operators, hence ‘-3\*\*2’ evaluates as ‘9’, not ‘-9’. Use
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parentheses where necessary: ‘-(3\*\*2)’. This is for compatibility with
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other shells.
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<span id="index-mathematical-functions_002c-use-of"></span>
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<span id="index-functions_002c-math_002c-use-of"></span>
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<span id="index-mathematical-functions_002c-use-of"></span> <span
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id="index-functions_002c-math_002c-use-of"></span>
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Mathematical functions can be called with the syntax
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‘`func``(``args``)`’, where the function decides if the `args` is
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used as a string or a comma-separated list of arithmetic expressions.
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The shell currently defines no mathematical functions by default, but
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the module `zsh/mathfunc` may be loaded with the `zmodload` builtin to
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provide standard floating point mathematical functions.
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Mathematical functions can be called with the syntax ‘`func`(`args`)’,
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where the function decides if the `args` is used as a string or a
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comma-separated list of arithmetic expressions. The shell currently
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defines no mathematical functions by default, but the module
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zsh/mathfunc may be loaded with the zmodload builtin to provide standard
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floating point mathematical functions.
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An expression of the form ‘`##``x`’ where `x` is any character sequence
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such as ‘`a`’, ‘`^A`’, or ‘`\M-\C-x`’ gives the value of this character
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and an expression of the form ‘`#``name`’ gives the value of the first
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An expression of the form ‘##`x`’ where `x` is any character sequence
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such as ‘a’, ‘^A’, or ‘\\M-\\C-x’ gives the value of this character and
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an expression of the form ‘#`name`’ gives the value of the first
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character of the contents of the parameter `name`. Character values are
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according to the character set used in the current locale; for multibyte
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character handling the option `MULTIBYTE` must be set. Note that this
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form is different from ‘`$#``name`’, a standard parameter substitution
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which gives the length of the parameter `name`. ‘`#\`’ is accepted
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instead of ‘`##`’, but its use is deprecated.
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character handling the option MULTIBYTE must be set. Note that this form
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is different from ‘$#`name`’, a standard parameter substitution which
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gives the length of the parameter `name`. ‘#\\’ is accepted instead of
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‘##’, but its use is deprecated.
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Named parameters and subscripted arrays can be referenced by name within
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an arithmetic expression without using the parameter expansion syntax.
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@ -300,46 +297,46 @@ For example,
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<div class="example">
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||||
|
||||
``` example
|
||||
```zsh
|
||||
((val2 = val1 * 2))
|
||||
```
|
||||
|
||||
</div>
|
||||
|
||||
assigns twice the value of `$val1` to the parameter named `val2`.
|
||||
assigns twice the value of $val1 to the parameter named val2.
|
||||
|
||||
An internal integer representation of a named parameter can be specified
|
||||
with the `integer` builtin.
|
||||
<span id="index-parameters_002c-integer"></span>
|
||||
<span id="index-integer-parameters"></span>
|
||||
<span id="index-integer_002c-use-of"></span> Arithmetic evaluation is
|
||||
with the integer builtin. <span
|
||||
id="index-parameters_002c-integer"></span> <span
|
||||
id="index-integer-parameters"></span> <span
|
||||
id="index-integer_002c-use-of"></span> Arithmetic evaluation is
|
||||
performed on the value of each assignment to a named parameter declared
|
||||
integer in this manner. Assigning a floating point number to an integer
|
||||
results in rounding towards zero.
|
||||
|
||||
<span id="index-parameters_002c-floating-point"></span>
|
||||
<span id="index-floating-point-parameters"></span>
|
||||
<span id="index-float_002c-use-of"></span>
|
||||
<span id="index-parameters_002c-floating-point"></span> <span
|
||||
id="index-floating-point-parameters"></span> <span
|
||||
id="index-float_002c-use-of"></span>
|
||||
|
||||
Likewise, floating point numbers can be declared with the `float`
|
||||
builtin; there are two types, differing only in their output format, as
|
||||
described for the `typeset` builtin. The output format can be bypassed
|
||||
by using arithmetic substitution instead of the parameter substitution,
|
||||
i.e. ‘`${``float``}`’ uses the defined format, but ‘`$((``float``))`’
|
||||
uses a generic floating point format.
|
||||
Likewise, floating point numbers can be declared with the float builtin;
|
||||
there are two types, differing only in their output format, as described
|
||||
for the typeset builtin. The output format can be bypassed by using
|
||||
arithmetic substitution instead of the parameter substitution, i.e.
|
||||
‘${`float`}’ uses the defined format, but ‘$((`float`))’ uses a generic
|
||||
floating point format.
|
||||
|
||||
Promotion of integer to floating point values is performed where
|
||||
necessary. In addition, if any operator which requires an integer
|
||||
(‘`&`’, ‘`|`’, ‘`^`’, ‘`<<`’, ‘`>>`’ and their equivalents with
|
||||
assignment) is given a floating point argument, it will be silently
|
||||
rounded towards zero except for ‘`~`’ which rounds down.
|
||||
necessary. In addition, if any operator which requires an integer (‘&’,
|
||||
‘\|’, ‘^’, ‘\<\<’, ‘>\>’ and their equivalents with assignment) is given
|
||||
a floating point argument, it will be silently rounded towards zero
|
||||
except for ‘\~’ which rounds down.
|
||||
|
||||
Users should beware that, in common with many other programming
|
||||
languages but not software designed for calculation, the evaluation of
|
||||
an expression in zsh is taken a term at a time and promotion of integers
|
||||
to floating point does not occur in terms only containing integers. A
|
||||
typical result of this is that a division such as `6/8` is truncated, in
|
||||
this being rounded towards 0. The `FORCE_FLOAT` shell option can be used
|
||||
typical result of this is that a division such as 6/8 is truncated, in
|
||||
this being rounded towards 0. The FORCE_FLOAT shell option can be used
|
||||
in scripts or functions where floating point evaluation is required
|
||||
throughout.
|
||||
|
||||
@ -347,14 +344,14 @@ Scalar variables can hold integer or floating point values at different
|
||||
times; there is no memory of the numeric type in this case.
|
||||
|
||||
If a variable is first assigned in a numeric context without previously
|
||||
being declared, it will be implicitly typed as `integer` or `float` and
|
||||
being declared, it will be implicitly typed as integer or float and
|
||||
retain that type either until the type is explicitly changed or until
|
||||
the end of the scope. This can have unforeseen consequences. For
|
||||
example, in the loop
|
||||
|
||||
<div class="example">
|
||||
|
||||
``` example
|
||||
```zsh
|
||||
for (( f = 0; f < 1; f += 0.1 )); do
|
||||
# use $f
|
||||
done
|
||||
@ -362,15 +359,15 @@ done
|
||||
|
||||
</div>
|
||||
|
||||
if `f` has not already been declared, the first assignment will cause it
|
||||
to be created as an integer, and consequently the operation ‘`f += 0.1`’
|
||||
if f has not already been declared, the first assignment will cause it
|
||||
to be created as an integer, and consequently the operation ‘f += 0.1’
|
||||
will always cause the result to be truncated to zero, so that the loop
|
||||
will fail. A simple fix would be to turn the initialization into ‘`f
|
||||
= 0.0`’. It is therefore best to declare numeric variables with explicit
|
||||
will fail. A simple fix would be to turn the initialization into ‘f =
|
||||
0.0’. It is therefore best to declare numeric variables with explicit
|
||||
types.
|
||||
|
||||
-----
|
||||
------------------------------------------------------------------------
|
||||
|
||||
This document was generated on *February 15, 2020* using
|
||||
[*texi2html 5.0*](http://www.nongnu.org/texi2html/).
|
||||
Zsh version 5.8, released on February 14, 2020.
|
||||
This document was generated on *May 14, 2022* using [*texi2html
|
||||
5.0*](http://www.nongnu.org/texi2html/).
|
||||
Zsh version 5.9, released on May 14, 2022.
|
||||
|
||||
File diff suppressed because it is too large
Load Diff
@ -6,15 +6,15 @@
|
||||
|
||||
<!-- END doctoc generated TOC please keep comment here to allow auto update -->
|
||||
|
||||
<span id="Command-Execution"></span>
|
||||
<span id="Command-Execution-1"></span>
|
||||
<span id="Command-Execution"></span> <span
|
||||
id="Command-Execution-1"></span>
|
||||
|
||||
# 8 Command Execution
|
||||
|
||||
<span id="index-command-execution"></span>
|
||||
<span id="index-execution_002c-of-commands"></span>
|
||||
<span id="index-command-not-found_002c-handling-of"></span>
|
||||
<span id="index-command_005fnot_005ffound_005fhandler"></span>
|
||||
<span id="index-command-execution"></span> <span
|
||||
id="index-execution_002c-of-commands"></span> <span
|
||||
id="index-command-not-found_002c-handling-of"></span> <span
|
||||
id="index-command_005fnot_005ffound_005fhandler"></span>
|
||||
|
||||
If a command name contains no slashes, the shell attempts to locate it.
|
||||
If there exists a shell function by that name, the function is invoked
|
||||
@ -23,28 +23,37 @@ shell builtin by that name, the builtin is invoked.
|
||||
|
||||
<span id="index-path_002c-use-of"></span>
|
||||
|
||||
Otherwise, the shell searches each element of `$path` for a search is
|
||||
unsuccessful, the shell prints an error message and returns a nonzero
|
||||
exit status.
|
||||
Otherwise, the shell searches each element of $path for a
|
||||
|
||||
If execution fails: an error message is printed, and one of the
|
||||
following values is returned.
|
||||
|
||||
127
|
||||
|
||||
The search was unsuccessful. The error message is ‘command not found:
|
||||
`cmd`’.
|
||||
|
||||
126
|
||||
|
||||
directory or special file, or is not a script and is in a format
|
||||
unrecognized by the operating system. The exact conditions and error
|
||||
message are operating system-dependent; see execve(2).
|
||||
|
||||
and the file is not a directory, it is assumed to be a shell script.
|
||||
`/bin/sh` is spawned to execute it. If the program is a file beginning
|
||||
with ‘`#!`’, the remainder of the first line specifies an interpreter
|
||||
for the program. The shell will execute the specified interpreter on
|
||||
/bin/sh is spawned to execute it. If the program is a file beginning
|
||||
with ‘#!’, the remainder of the first line specifies an interpreter for
|
||||
the program. The shell will execute the specified interpreter on
|
||||
operating systems that do
|
||||
|
||||
If no external command is found but a function
|
||||
`command_not_found_handler` exists the shell executes this function with
|
||||
all command line arguments. The return status of the function becomes
|
||||
the status of the command. If the function wishes to mimic the behaviour
|
||||
of the shell when the command is not found, it should print the message
|
||||
‘`command not found:` `cmd`’ to standard error and return status 127.
|
||||
If no external command is found but a function command_not_found_handler
|
||||
exists the shell executes this function with all command line arguments.
|
||||
The return status of the function becomes the status of the command.
|
||||
Note that the handler is executed in a subshell forked to execute an
|
||||
external command, hence changes to directories, shell parameters, etc.
|
||||
have no effect on the main shell.
|
||||
|
||||
-----
|
||||
------------------------------------------------------------------------
|
||||
|
||||
This document was generated on *February 15, 2020* using
|
||||
[*texi2html 5.0*](http://www.nongnu.org/texi2html/).
|
||||
Zsh version 5.8, released on February 14, 2020.
|
||||
This document was generated on *May 14, 2022* using [*texi2html
|
||||
5.0*](http://www.nongnu.org/texi2html/).
|
||||
Zsh version 5.9, released on May 14, 2022.
|
||||
|
||||
File diff suppressed because it is too large
Load Diff
File diff suppressed because it is too large
Load Diff
File diff suppressed because it is too large
Load Diff
@ -6,198 +6,195 @@
|
||||
|
||||
<!-- END doctoc generated TOC please keep comment here to allow auto update -->
|
||||
|
||||
<span id="Conditional-Expressions"></span>
|
||||
<span id="Conditional-Expressions-1"></span>
|
||||
<span id="Conditional-Expressions"></span> <span
|
||||
id="Conditional-Expressions-1"></span>
|
||||
|
||||
# 12 Conditional Expressions
|
||||
|
||||
<span id="index-conditional-expressions"></span>
|
||||
<span id="index-expressions_002c-conditional"></span>
|
||||
<span id="index-conditional-expressions"></span> <span
|
||||
id="index-expressions_002c-conditional"></span>
|
||||
|
||||
A *conditional expression* is used with the `[[` compound command to
|
||||
A *conditional expression* is used with the \[\[ compound command to
|
||||
test attributes of files and to compare strings. Each expression can be
|
||||
constructed from one or more of the following unary or binary
|
||||
expressions:
|
||||
|
||||
- `-a` `file`
|
||||
true if `file` exists.
|
||||
-a `file`
|
||||
true if `file` exists.
|
||||
|
||||
- `-b` `file`
|
||||
true if `file` exists and is a block special file.
|
||||
-b `file`
|
||||
true if `file` exists and is a block special file.
|
||||
|
||||
- `-c` `file`
|
||||
true if `file` exists and is a character special file.
|
||||
-c `file`
|
||||
true if `file` exists and is a character special file.
|
||||
|
||||
- `-d` `file`
|
||||
true if `file` exists and is a directory.
|
||||
-d `file`
|
||||
true if `file` exists and is a directory.
|
||||
|
||||
- `-e` `file`
|
||||
true if `file` exists.
|
||||
-e `file`
|
||||
true if `file` exists.
|
||||
|
||||
- `-f` `file`
|
||||
true if `file` exists and is a regular file.
|
||||
-f `file`
|
||||
true if `file` exists and is a regular file.
|
||||
|
||||
- `-g` `file`
|
||||
true if `file` exists and has its setgid bit set.
|
||||
-g `file`
|
||||
true if `file` exists and has its setgid bit set.
|
||||
|
||||
- `-h` `file`
|
||||
true if `file` exists and is a symbolic link.
|
||||
-h `file`
|
||||
true if `file` exists and is a symbolic link.
|
||||
|
||||
- `-k` `file`
|
||||
true if `file` exists and has its sticky bit set.
|
||||
-k `file`
|
||||
true if `file` exists and has its sticky bit set.
|
||||
|
||||
- `-n` `string`
|
||||
true if length of `string` is non-zero.
|
||||
-n `string`
|
||||
true if length of `string` is non-zero.
|
||||
|
||||
- `-o` `option`
|
||||
true if option named `option` is on. `option` may be a single
|
||||
character, in which case it is a single letter option name. (See
|
||||
[Specifying Options](Options.html#Specifying-Options).)
|
||||
-o `option`
|
||||
true if option named `option` is on. `option` may be a single character,
|
||||
in which case it is a single letter option name. (See [Specifying
|
||||
Options](Options.html#Specifying-Options).)
|
||||
|
||||
When no option named `option` exists, and the `POSIX_BUILTINS`
|
||||
option hasn’t been set, return 3 with a warning. If that option is
|
||||
set, return 1 with no warning.
|
||||
When no option named `option` exists, and the POSIX_BUILTINS option
|
||||
hasn’t been set, return 3 with a warning. If that option is set, return
|
||||
1 with no warning.
|
||||
|
||||
- `-p` `file`
|
||||
true if `file` exists and is a FIFO special file (named pipe).
|
||||
-p `file`
|
||||
true if `file` exists and is a FIFO special file (named pipe).
|
||||
|
||||
- `-r` `file`
|
||||
true if `file` exists and is readable by current process.
|
||||
-r `file`
|
||||
true if `file` exists and is readable by current process.
|
||||
|
||||
- `-s` `file`
|
||||
true if `file` exists and has size greater than zero.
|
||||
-s `file`
|
||||
true if `file` exists and has size greater than zero.
|
||||
|
||||
- `-t` `fd`
|
||||
true if file descriptor number `fd` is open and associated with a
|
||||
terminal device. (note: `fd` is not optional)
|
||||
-t `fd`
|
||||
true if file descriptor number `fd` is open and associated with a
|
||||
terminal device. (note: `fd` is not optional)
|
||||
|
||||
- `-u` `file`
|
||||
true if `file` exists and has its setuid bit set.
|
||||
-u `file`
|
||||
true if `file` exists and has its setuid bit set.
|
||||
|
||||
- `-v` `varname`
|
||||
true if shell variable `varname` is set.
|
||||
-v `varname`
|
||||
true if shell variable `varname` is set.
|
||||
|
||||
- `-w` `file`
|
||||
`-x` `file`
|
||||
`-z` `string`
|
||||
true if length of `string` is zero.
|
||||
-w `file`
|
||||
-x `file`
|
||||
-z `string`
|
||||
true if length of `string` is zero.
|
||||
|
||||
- `-L` `file`
|
||||
true if `file` exists and is a symbolic link.
|
||||
-L `file`
|
||||
true if `file` exists and is a symbolic link.
|
||||
|
||||
- `-O` `file`
|
||||
true if `file` exists and is owned by the effective user ID of this
|
||||
process.
|
||||
-O `file`
|
||||
true if `file` exists and is owned by the effective user ID of this
|
||||
process.
|
||||
|
||||
- `-G` `file`
|
||||
true if `file` exists and its group matches the effective group ID
|
||||
of this process.
|
||||
-G `file`
|
||||
true if `file` exists and its group matches the effective group ID of
|
||||
this process.
|
||||
|
||||
- `-S` `file`
|
||||
true if `file` exists and is a socket.
|
||||
-S `file`
|
||||
true if `file` exists and is a socket.
|
||||
|
||||
- `-N` `file`
|
||||
true if `file` exists and its access time is not newer than its
|
||||
modification time.
|
||||
-N `file`
|
||||
true if `file` exists and its access time is not newer than its
|
||||
modification time.
|
||||
|
||||
- `file1` `-nt` `file2`
|
||||
true if `file1` exists and is newer than `file2`.
|
||||
`file1` -nt `file2`
|
||||
true if `file1` exists and is newer than `file2`.
|
||||
|
||||
- `file1` `-ot` `file2`
|
||||
true if `file1` exists and is older than `file2`.
|
||||
`file1` -ot `file2`
|
||||
true if `file1` exists and is older than `file2`.
|
||||
|
||||
- `file1` `-ef` `file2`
|
||||
true if `file1` and `file2` exist and refer to the same file.
|
||||
`file1` -ef `file2`
|
||||
true if `file1` and `file2` exist and refer to the same file.
|
||||
|
||||
- `string` `=` `pattern`
|
||||
`string` `==` `pattern`
|
||||
true if `string` matches `pattern`. The two forms are exactly
|
||||
equivalent. The ‘`=`’ form is the traditional shell syntax (and
|
||||
hence the only one generally used with the `test` and `[` builtins);
|
||||
the ‘`==`’ form provides compatibility with other sorts of computer
|
||||
language.
|
||||
`string` = `pattern`
|
||||
`string` == `pattern`
|
||||
true if `string` matches `pattern`. The two forms are exactly
|
||||
equivalent. The ‘=’ form is the traditional shell syntax (and hence the
|
||||
only one generally used with the test and \[ builtins); the ‘==’ form
|
||||
provides compatibility with other sorts of computer language.
|
||||
|
||||
- `string` `!=` `pattern`
|
||||
true if `string` does not match `pattern`.
|
||||
`string` != `pattern`
|
||||
true if `string` does not match `pattern`.
|
||||
|
||||
- `string` `=~` `regexp`
|
||||
true if `string` matches the regular expression `regexp`. If the
|
||||
option `RE_MATCH_PCRE` is set `regexp` is tested as a PCRE regular
|
||||
expression using the `zsh/pcre` module, else it is tested as a POSIX
|
||||
extended regular expression using the `zsh/regex` module. Upon
|
||||
successful match, some variables will be updated; no variables are
|
||||
changed if the matching fails.
|
||||
`string` =\~ `regexp`
|
||||
true if `string` matches the regular expression `regexp`. If the option
|
||||
RE_MATCH_PCRE is set `regexp` is tested as a PCRE regular expression
|
||||
using the zsh/pcre module, else it is tested as a POSIX extended regular
|
||||
expression using the zsh/regex module. Upon successful match, some
|
||||
variables will be updated; no variables are changed if the matching
|
||||
fails.
|
||||
|
||||
If the option `BASH_REMATCH` is not set the scalar parameter `MATCH`
|
||||
is set to the substring that matched the pattern and the integer
|
||||
parameters `MBEGIN` and `MEND` to the index of the start and end,
|
||||
respectively, of the match in `string`, such that if `string` is
|
||||
contained in variable `var` the expression ‘`${var[$MBEGIN,$MEND]}`’
|
||||
is identical to ‘`$MATCH`’. The setting of the option `KSH_ARRAYS`
|
||||
is respected. Likewise, the array `match` is set to the substrings
|
||||
that matched parenthesised subexpressions and the arrays `mbegin`
|
||||
and `mend` to the indices of the start and end positions,
|
||||
respectively, of the substrings within `string`. The arrays are not
|
||||
set if there were no parenthesised subexpressions. For example, if
|
||||
the string ‘`a short string`’ is matched against the regular
|
||||
expression ‘`s(...)t`’, then (assuming the option `KSH_ARRAYS` is
|
||||
not set) `MATCH`, `MBEGIN` and `MEND` are ‘`short`’, `3` and `7`,
|
||||
respectively, while `match`, `mbegin` and `mend` are single entry
|
||||
arrays containing the strings ‘`hor`’, ‘`4`’ and ‘`6`’,
|
||||
respectively.
|
||||
If the option BASH_REMATCH is not set the scalar parameter MATCH is set
|
||||
to the substring that matched the pattern and the integer parameters
|
||||
MBEGIN and MEND to the index of the start and end, respectively, of the
|
||||
match in `string`, such that if `string` is contained in variable var
|
||||
the expression ‘${var\[$MBEGIN,$MEND\]}’ is identical to ‘$MATCH’. The
|
||||
setting of the option KSH_ARRAYS is respected. Likewise, the array match
|
||||
is set to the substrings that matched parenthesised subexpressions and
|
||||
the arrays mbegin and mend to the indices of the start and end
|
||||
positions, respectively, of the substrings within `string`. The arrays
|
||||
are not set if there were no parenthesised subexpressions. For example,
|
||||
if the string ‘a short string’ is matched against the regular expression
|
||||
‘s(...)t’, then (assuming the option KSH_ARRAYS is not set) MATCH,
|
||||
MBEGIN and MEND are ‘short’, 3 and 7, respectively, while match, mbegin
|
||||
and mend are single entry arrays containing the strings ‘hor’, ‘4’ and
|
||||
‘6’, respectively.
|
||||
|
||||
If the option `BASH_REMATCH` is set the array `BASH_REMATCH` is set
|
||||
to the substring that matched the pattern followed by the substrings
|
||||
that matched parenthesised subexpressions within the pattern.
|
||||
If the option BASH_REMATCH is set the array BASH_REMATCH is set to the
|
||||
substring that matched the pattern followed by the substrings that
|
||||
matched parenthesised subexpressions within the pattern.
|
||||
|
||||
- `string1` `<` `string2`
|
||||
true if `string1` comes before `string2` based on ASCII value of
|
||||
their characters.
|
||||
`string1` \< `string2`
|
||||
true if `string1` comes before `string2` based on ASCII value of their
|
||||
characters.
|
||||
|
||||
- `string1` `>` `string2`
|
||||
true if `string1` comes after `string2` based on ASCII value of
|
||||
their characters.
|
||||
`string1` > `string2`
|
||||
true if `string1` comes after `string2` based on ASCII value of their
|
||||
characters.
|
||||
|
||||
- `exp1` `-eq` `exp2`
|
||||
true if `exp1` is numerically equal to `exp2`. Note that for purely
|
||||
numeric comparisons use of the `((``...``))` builtin described in
|
||||
[Arithmetic
|
||||
Evaluation](Arithmetic-Evaluation.html#Arithmetic-Evaluation) is
|
||||
more convenient than conditional expressions.
|
||||
`exp1` -eq `exp2`
|
||||
true if `exp1` is numerically equal to `exp2`. Note that for purely
|
||||
numeric comparisons use of the ((`...`)) builtin described in
|
||||
[Arithmetic
|
||||
Evaluation](Arithmetic-Evaluation.html#Arithmetic-Evaluation) is more
|
||||
convenient than conditional expressions.
|
||||
|
||||
- `exp1` `-ne` `exp2`
|
||||
true if `exp1` is numerically not equal to `exp2`.
|
||||
`exp1` -ne `exp2`
|
||||
true if `exp1` is numerically not equal to `exp2`.
|
||||
|
||||
- `exp1` `-lt` `exp2`
|
||||
true if `exp1` is numerically less than `exp2`.
|
||||
`exp1` -lt `exp2`
|
||||
true if `exp1` is numerically less than `exp2`.
|
||||
|
||||
- `exp1` `-gt` `exp2`
|
||||
true if `exp1` is numerically greater than `exp2`.
|
||||
`exp1` -gt `exp2`
|
||||
true if `exp1` is numerically greater than `exp2`.
|
||||
|
||||
- `exp1` `-le` `exp2`
|
||||
true if `exp1` is numerically less than or equal to `exp2`.
|
||||
`exp1` -le `exp2`
|
||||
true if `exp1` is numerically less than or equal to `exp2`.
|
||||
|
||||
- `exp1` `-ge` `exp2`
|
||||
true if `exp1` is numerically greater than or equal to `exp2`.
|
||||
`exp1` -ge `exp2`
|
||||
true if `exp1` is numerically greater than or equal to `exp2`.
|
||||
|
||||
- `(` `exp` `)`
|
||||
true if `exp` is true.
|
||||
( `exp` )
|
||||
true if `exp` is true.
|
||||
|
||||
- `!` `exp`
|
||||
true if `exp` is false.
|
||||
! `exp`
|
||||
true if `exp` is false.
|
||||
|
||||
- `exp1` `&&` `exp2`
|
||||
true if `exp1` and `exp2` are both true.
|
||||
`exp1` && `exp2`
|
||||
true if `exp1` and `exp2` are both true.
|
||||
|
||||
- `exp1` `||` `exp2`
|
||||
true if either `exp1` or `exp2` is true.
|
||||
`exp1` \|\| `exp2`
|
||||
true if either `exp1` or `exp2` is true.
|
||||
|
||||
For compatibility, if there is a single argument that is not
|
||||
syntactically significant, typically a variable, the condition is
|
||||
treated as a test for whether the expression expands as a string of
|
||||
non-zero length. In other words, `[[ $var ]]` is the same as `[[ -n $var
|
||||
]]`. It is recommended that the second, explicit, form be used where
|
||||
possible.
|
||||
non-zero length. In other words, \[\[ $var \]\] is the same as \[\[ -n
|
||||
$var \]\]. It is recommended that the second, explicit, form be used
|
||||
where possible.
|
||||
|
||||
Normal shell expansion is performed on the `file`, `string` and
|
||||
`pattern` arguments, but the result of each expansion is constrained to
|
||||
@ -205,66 +202,65 @@ be a single word, similar to the effect of double quotes.
|
||||
|
||||
Filename generation is not performed on any form of argument to
|
||||
conditions. However, it can be forced in any case where normal shell
|
||||
expansion is valid and when the option `EXTENDED_GLOB` is in effect by
|
||||
using an explicit glob qualifier of the form `(#q)` at the end of the
|
||||
string. A normal glob qualifier expression may appear between the ‘`q`’
|
||||
expansion is valid and when the option EXTENDED_GLOB is in effect by
|
||||
using an explicit glob qualifier of the form (#q) at the end of the
|
||||
string. A normal glob qualifier expression may appear between the ‘q’
|
||||
and the closing parenthesis; if none appears the expression has no
|
||||
effect beyond causing filename generation. The results of filename
|
||||
generation are joined together to form a single word, as with the
|
||||
results of other forms of expansion.
|
||||
|
||||
This special use of filename generation is only available with the `[[`
|
||||
syntax. If the condition occurs within the `[` or `test` builtin
|
||||
commands then globbing occurs instead as part of normal command line
|
||||
expansion before the condition is evaluated. In this case it may
|
||||
generate multiple words which are likely to confuse the syntax of the
|
||||
test command.
|
||||
This special use of filename generation is only available with the \[\[
|
||||
syntax. If the condition occurs within the \[ or test builtin commands
|
||||
then globbing occurs instead as part of normal command line expansion
|
||||
before the condition is evaluated. In this case it may generate multiple
|
||||
words which are likely to confuse the syntax of the test command.
|
||||
|
||||
For example,
|
||||
|
||||
<div class="example">
|
||||
|
||||
``` example
|
||||
```zsh
|
||||
[[ -n file*(#qN) ]]
|
||||
```
|
||||
|
||||
</div>
|
||||
|
||||
produces status zero if and only if there is at least one file in the
|
||||
current directory beginning with the string ‘`file`’. The globbing
|
||||
qualifier `N` ensures that the expression is empty if there is no
|
||||
matching file.
|
||||
current directory beginning with the string ‘file’. The globbing
|
||||
qualifier N ensures that the expression is empty if there is no matching
|
||||
file.
|
||||
|
||||
Pattern metacharacters are active for the `pattern` arguments; the
|
||||
patterns are the same as those used for filename generation, see
|
||||
[Filename Generation](Expansion.html#Filename-Generation), but there is
|
||||
no special behaviour of ‘`/`’ nor initial dots, and no glob qualifiers
|
||||
are allowed.
|
||||
no special behaviour of ‘/’ nor initial dots, and no glob qualifiers are
|
||||
allowed.
|
||||
|
||||
In each of the above expressions, if `file` is of the form
|
||||
‘`/dev/fd/``n`’, where `n` is an integer, then the test applied to the
|
||||
‘/dev/fd/`n`’, where `n` is an integer, then the test applied to the
|
||||
open file whose descriptor number is `n`, even if the underlying system
|
||||
does not support the `/dev/fd` directory.
|
||||
does not support the /dev/fd directory.
|
||||
|
||||
In the forms which do numeric comparison, the expressions `exp` undergo
|
||||
arithmetic expansion as if they were enclosed in `$((``...``))`.
|
||||
arithmetic expansion as if they were enclosed in $((`...`)).
|
||||
|
||||
For example, the following:
|
||||
|
||||
<div class="example">
|
||||
|
||||
``` example
|
||||
```zsh
|
||||
[[ ( -f foo || -f bar ) && $report = y* ]] && print File exists.
|
||||
```
|
||||
|
||||
</div>
|
||||
|
||||
tests if either file `foo` or file `bar` exists, and if so, if the value
|
||||
of the parameter `report` begins with ‘`y`’; if the complete condition
|
||||
is true, the message ‘`File exists.`’ is printed.
|
||||
tests if either file foo or file bar exists, and if so, if the value of
|
||||
the parameter report begins with ‘y’; if the complete condition is true,
|
||||
the message ‘File exists.’ is printed.
|
||||
|
||||
-----
|
||||
------------------------------------------------------------------------
|
||||
|
||||
This document was generated on *February 15, 2020* using
|
||||
[*texi2html 5.0*](http://www.nongnu.org/texi2html/).
|
||||
Zsh version 5.8, released on February 14, 2020.
|
||||
This document was generated on *May 14, 2022* using [*texi2html
|
||||
5.0*](http://www.nongnu.org/texi2html/).
|
||||
Zsh version 5.9, released on May 14, 2022.
|
||||
|
||||
File diff suppressed because it is too large
Load Diff
@ -8,109 +8,106 @@
|
||||
|
||||
<!-- END doctoc generated TOC please keep comment here to allow auto update -->
|
||||
|
||||
<span id="Files"></span> <span id="Files-1"></span>
|
||||
<span id="Files"></span> <span id="Files-2"></span>
|
||||
|
||||
# 5 Files
|
||||
|
||||
-----
|
||||
------------------------------------------------------------------------
|
||||
|
||||
<span id="Startup_002fShutdown-Files"></span>
|
||||
|
||||
## 5.1 Startup/Shutdown Files
|
||||
|
||||
<span id="index-files_002c-startup"></span>
|
||||
<span id="index-startup-files"></span>
|
||||
<span id="index-files_002c-shutdown"></span>
|
||||
<span id="index-shutdown-files"></span>
|
||||
<span id="index-RCS_002c-use-of"></span>
|
||||
<span id="index-GLOBAL_005fRCS_002c-use-of"></span>
|
||||
<span id="index-NO_005fRCS_002c-use-of"></span>
|
||||
<span id="index-NO_005fGLOBAL_005fRCS_002c-use-of"></span>
|
||||
<span id="index-ZDOTDIR_002c-use-of"></span>
|
||||
<span id="index-zshenv"></span>
|
||||
<span id="index-files_002c-startup"></span> <span
|
||||
id="index-startup-files"></span> <span
|
||||
id="index-files_002c-shutdown"></span> <span
|
||||
id="index-shutdown-files"></span> <span
|
||||
id="index-RCS_002c-use-of"></span> <span
|
||||
id="index-GLOBAL_005fRCS_002c-use-of"></span> <span
|
||||
id="index-NO_005fRCS_002c-use-of"></span> <span
|
||||
id="index-NO_005fGLOBAL_005fRCS_002c-use-of"></span> <span
|
||||
id="index-ZDOTDIR_002c-use-of"></span> <span id="index-zshenv"></span>
|
||||
|
||||
Commands are first read from `/etc/zshenv`; this cannot be overridden.
|
||||
Subsequent behaviour is modified by the `RCS` and `GLOBAL_RCS` options;
|
||||
the former affects all startup files, while the second only affects
|
||||
global startup files (those shown here with an path starting with a
|
||||
`/`). If one of the options is unset at any point, any subsequent
|
||||
startup file(s) of the corresponding type will not be read. It is also
|
||||
possible for a file in `$ZDOTDIR` to re-enable `GLOBAL_RCS`. Both `RCS`
|
||||
and `GLOBAL_RCS` are set by default.
|
||||
Commands are first read from /etc/zshenv; this cannot be overridden.
|
||||
Subsequent behaviour is modified by the RCS and GLOBAL_RCS options; the
|
||||
former affects all startup files, while the second only affects global
|
||||
startup files (those shown here with an path starting with a /). If one
|
||||
of the options is unset at any point, any subsequent startup file(s) of
|
||||
the corresponding type will not be read. It is also possible for a file
|
||||
in $ZDOTDIR to re-enable GLOBAL_RCS. Both RCS and GLOBAL_RCS are set by
|
||||
default.
|
||||
|
||||
Commands are then read from `$ZDOTDIR/.zshenv`.
|
||||
<span id="index-LOGIN_002c-use-of"></span>
|
||||
<span id="index-zprofile"></span> If the shell is a login shell,
|
||||
commands are read from `/etc/zprofile` and then `$ZDOTDIR/.zprofile`.
|
||||
<span id="index-zshrc"></span> Then, if the shell is interactive,
|
||||
commands are read from `/etc/zshrc` and then `$ZDOTDIR/.zshrc`.
|
||||
<span id="index-zlogin"></span> Finally, if the shell is a login shell,
|
||||
`/etc/zlogin` and `$ZDOTDIR/.zlogin` are read.
|
||||
Commands are then read from $ZDOTDIR/.zshenv. <span
|
||||
id="index-LOGIN_002c-use-of"></span> <span id="index-zprofile"></span>
|
||||
If the shell is a login shell, commands are read from /etc/zprofile and
|
||||
then $ZDOTDIR/.zprofile. <span id="index-zshrc"></span> Then, if the
|
||||
shell is interactive, commands are read from /etc/zshrc and then
|
||||
$ZDOTDIR/.zshrc. <span id="index-zlogin"></span> Finally, if the shell
|
||||
is a login shell, /etc/zlogin and $ZDOTDIR/.zlogin are read.
|
||||
|
||||
<span id="index-zlogout"></span>
|
||||
|
||||
When a login shell exits, the files `$ZDOTDIR/.zlogout` and then
|
||||
`/etc/zlogout` are read. This happens with either an explicit exit via
|
||||
the `exit` or `logout` commands, or an implicit exit by reading
|
||||
end-of-file from the terminal. However, if the shell terminates due to
|
||||
`exec`’ing another process, the logout files are not read. These are
|
||||
also affected by the `RCS` and `GLOBAL_RCS` options. Note also that the
|
||||
`RCS` option affects the saving of history files, i.e. if `RCS` is unset
|
||||
when the shell exits, no history file will be saved.
|
||||
When a login shell exits, the files $ZDOTDIR/.zlogout and then
|
||||
/etc/zlogout are read. This happens with either an explicit exit via the
|
||||
exit or logout commands, or an implicit exit by reading end-of-file from
|
||||
the terminal. However, if the shell terminates due to exec’ing another
|
||||
process, the logout files are not read. These are also affected by the
|
||||
RCS and GLOBAL_RCS options. Note also that the RCS option affects the
|
||||
saving of history files, i.e. if RCS is unset when the shell exits, no
|
||||
history file will be saved.
|
||||
|
||||
<span id="index-HOME_002c-use-of"></span>
|
||||
|
||||
If `ZDOTDIR` is unset, `HOME` is used instead. Files listed above as
|
||||
being in `/etc` may be in another directory, depending on the
|
||||
installation.
|
||||
If ZDOTDIR is unset, HOME is used instead. Files listed above as being
|
||||
in /etc may be in another directory, depending on the installation.
|
||||
|
||||
As `/etc/zshenv` is run for all instances of zsh, it is important that
|
||||
it be kept as small as possible. In particular, it is a good idea to put
|
||||
As /etc/zshenv is run for all instances of zsh, it is important that it
|
||||
be kept as small as possible. In particular, it is a good idea to put
|
||||
code that does not need to be run for every single shell behind a test
|
||||
of the form ‘`if [[ -o rcs ]]; then ...`’ so that it will not be
|
||||
executed when zsh is invoked with the ‘`-f`’ option.
|
||||
of the form ‘if \[\[ -o rcs \]\]; then ...’ so that it will not be
|
||||
executed when zsh is invoked with the ‘-f’ option.
|
||||
|
||||
-----
|
||||
------------------------------------------------------------------------
|
||||
|
||||
<span id="Files-2"></span>
|
||||
<span id="Files-1"></span>
|
||||
|
||||
## 5.2 Files
|
||||
|
||||
<span id="index-files-used"></span>
|
||||
|
||||
`$ZDOTDIR/.zshenv`
|
||||
$ZDOTDIR/.zshenv
|
||||
|
||||
`$ZDOTDIR/.zprofile`
|
||||
$ZDOTDIR/.zprofile
|
||||
|
||||
`$ZDOTDIR/.zshrc`
|
||||
$ZDOTDIR/.zshrc
|
||||
|
||||
`$ZDOTDIR/.zlogin`
|
||||
$ZDOTDIR/.zlogin
|
||||
|
||||
`$ZDOTDIR/.zlogout`
|
||||
$ZDOTDIR/.zlogout
|
||||
|
||||
`${TMPPREFIX}*` (default is /tmp/zsh\*)
|
||||
${TMPPREFIX}\* (default is /tmp/zsh\*)
|
||||
|
||||
`/etc/zshenv`
|
||||
/etc/zshenv
|
||||
|
||||
`/etc/zprofile`
|
||||
/etc/zprofile
|
||||
|
||||
`/etc/zshrc`
|
||||
/etc/zshrc
|
||||
|
||||
`/etc/zlogin`
|
||||
/etc/zlogin
|
||||
|
||||
`/etc/zlogout` (installation-specific - `/etc` is the default)
|
||||
/etc/zlogout (installation-specific - /etc is the default)
|
||||
|
||||
|
||||
|
||||
Any of these files may be pre-compiled with the `zcompile` builtin
|
||||
command ([Shell Builtin
|
||||
Any of these files may be pre-compiled with the zcompile builtin command
|
||||
([Shell Builtin
|
||||
Commands](Shell-Builtin-Commands.html#Shell-Builtin-Commands)). If a
|
||||
compiled file exists (named for the original file plus the `.zwc`
|
||||
compiled file exists (named for the original file plus the .zwc
|
||||
extension) and it is newer than the original file, the compiled file
|
||||
will be used instead.
|
||||
|
||||
-----
|
||||
------------------------------------------------------------------------
|
||||
|
||||
This document was generated on *February 15, 2020* using
|
||||
[*texi2html 5.0*](http://www.nongnu.org/texi2html/).
|
||||
Zsh version 5.8, released on February 14, 2020.
|
||||
This document was generated on *May 14, 2022* using [*texi2html
|
||||
5.0*](http://www.nongnu.org/texi2html/).
|
||||
Zsh version 5.9, released on May 14, 2022.
|
||||
|
||||
@ -11,55 +11,55 @@
|
||||
|
||||
<!-- END doctoc generated TOC please keep comment here to allow auto update -->
|
||||
|
||||
<span id="Functions"></span> <span id="Functions-3"></span>
|
||||
<span id="Functions"></span> <span id="Functions-4"></span>
|
||||
|
||||
# 9 Functions
|
||||
|
||||
<span id="index-functions"></span>
|
||||
<span id="index-function_002c-use-of"></span>
|
||||
<span id="index-functions"></span> <span
|
||||
id="index-function_002c-use-of"></span>
|
||||
|
||||
Shell functions are defined with the `function` reserved word or the
|
||||
special syntax ‘`funcname` `()`’. Shell functions are read in and stored
|
||||
Shell functions are defined with the function reserved word or the
|
||||
special syntax ‘`funcname` ()’. Shell functions are read in and stored
|
||||
internally. Alias names are resolved when the function is read.
|
||||
Functions are executed like commands with the arguments passed as
|
||||
positional parameters. (See [Command
|
||||
Execution](Command-Execution.html#Command-Execution).)
|
||||
|
||||
Functions execute in the same process as the caller and share all files
|
||||
and present working directory with the caller. A trap on `EXIT` set
|
||||
inside a function is executed after the function completes in the
|
||||
environment of the caller.
|
||||
and present working directory with the caller. A trap on EXIT set inside
|
||||
a function is executed after the function completes in the environment
|
||||
of the caller.
|
||||
|
||||
<span id="index-return_002c-use-of"></span>
|
||||
|
||||
The `return` builtin is used to return from function calls.
|
||||
The return builtin is used to return from function calls.
|
||||
|
||||
<span id="index-functions_002c-use-of"></span>
|
||||
|
||||
Function identifiers can be listed with the `functions` builtin.
|
||||
<span id="index-unfunction_002c-use-of"></span> Functions can be
|
||||
undefined with the `unfunction` builtin.
|
||||
Function identifiers can be listed with the functions builtin. <span
|
||||
id="index-unfunction_002c-use-of"></span> Functions can be undefined
|
||||
with the unfunction builtin.
|
||||
|
||||
-----
|
||||
------------------------------------------------------------------------
|
||||
|
||||
<span id="Autoloading-Functions"></span>
|
||||
|
||||
## 9.1 Autoloading Functions
|
||||
|
||||
<span id="index-autoloading-functions"></span>
|
||||
<span id="index-functions_002c-autoloading"></span>
|
||||
<span id="index-autoload_002c-use-of"></span>
|
||||
<span id="index-fpath_002c-use-of"></span>
|
||||
<span id="index-autoloading-functions"></span> <span
|
||||
id="index-functions_002c-autoloading"></span> <span
|
||||
id="index-autoload_002c-use-of"></span> <span
|
||||
id="index-fpath_002c-use-of"></span>
|
||||
|
||||
A function can be marked as *undefined* using the `autoload` builtin (or
|
||||
‘`functions -u`’ or ‘`typeset -fu`’). Such a function has no body. When
|
||||
the function is first executed, the shell searches for its definition
|
||||
using the elements of the `fpath` variable. Thus to define functions for
|
||||
A function can be marked as *undefined* using the autoload builtin (or
|
||||
‘functions -u’ or ‘typeset -fu’). Such a function has no body. When the
|
||||
function is first executed, the shell searches for its definition using
|
||||
the elements of the fpath variable. Thus to define functions for
|
||||
autoloading, a typical sequence is:
|
||||
|
||||
<div class="example">
|
||||
|
||||
``` example
|
||||
```zsh
|
||||
fpath=(~/myfuncs $fpath)
|
||||
autoload myfunc1 myfunc2 ...
|
||||
```
|
||||
@ -67,62 +67,60 @@ autoload myfunc1 myfunc2 ...
|
||||
</div>
|
||||
|
||||
The usual alias expansion during reading will be suppressed if the
|
||||
`autoload` builtin or its equivalent is given the option `-U`. This is
|
||||
autoload builtin or its equivalent is given the option -U. This is
|
||||
recommended for the use of functions supplied with the zsh distribution.
|
||||
<span id="index-zcompile_002c-use-of"></span> Note that for functions
|
||||
precompiled with the `zcompile` builtin command the flag `-U` must be
|
||||
provided when the `.zwc` file is created, as the corresponding
|
||||
information is compiled into the latter.
|
||||
precompiled with the zcompile builtin command the flag -U must be
|
||||
provided when the .zwc file is created, as the corresponding information
|
||||
is compiled into the latter.
|
||||
|
||||
For each `element` in `fpath`, the shell looks for three possible files,
|
||||
For each `element` in fpath, the shell looks for three possible files,
|
||||
the newest of which is used to load the definition for the function:
|
||||
|
||||
- `element``.zwc`
|
||||
A file created with the `zcompile` builtin command, which is
|
||||
expected to contain the definitions for all functions in the
|
||||
directory named `element`. The file is treated in the same manner as
|
||||
a directory containing files for functions and is searched for the
|
||||
definition of the function. If the definition is not found, the
|
||||
search for a definition proceeds with the other two possibilities
|
||||
described below.
|
||||
`element`.zwc
|
||||
A file created with the zcompile builtin command, which is expected to
|
||||
contain the definitions for all functions in the directory named
|
||||
`element`. The file is treated in the same manner as a directory
|
||||
containing files for functions and is searched for the definition of the
|
||||
function. If the definition is not found, the search for a definition
|
||||
proceeds with the other two possibilities described below.
|
||||
|
||||
If `element` already includes a `.zwc` extension (i.e. the extension
|
||||
was explicitly given by the user), `element` is searched for the
|
||||
definition of the function without comparing its age to that of
|
||||
other files; in fact, there does not need to be any directory named
|
||||
`element` without the suffix. Thus including an element such as
|
||||
‘`/usr/local/funcs.zwc`’ in `fpath` will speed up the search for
|
||||
functions, with the disadvantage that functions included must be
|
||||
explicitly recompiled by hand before the shell notices any changes.
|
||||
If `element` already includes a .zwc extension (i.e. the extension was
|
||||
explicitly given by the user), `element` is searched for the definition
|
||||
of the function without comparing its age to that of other files; in
|
||||
fact, there does not need to be any directory named `element` without
|
||||
the suffix. Thus including an element such as ‘/usr/local/funcs.zwc’ in
|
||||
fpath will speed up the search for functions, with the disadvantage that
|
||||
functions included must be explicitly recompiled by hand before the
|
||||
shell notices any changes.
|
||||
|
||||
- `element``/``function``.zwc`
|
||||
A file created with `zcompile`, which is expected to contain the
|
||||
definition for `function`. It may include other function definitions
|
||||
as well, but those are neither loaded nor executed; a file found in
|
||||
this way is searched *only* for the definition of `function`.
|
||||
`element`/`function`.zwc
|
||||
A file created with zcompile, which is expected to contain the
|
||||
definition for `function`. It may include other function definitions as
|
||||
well, but those are neither loaded nor executed; a file found in this
|
||||
way is searched *only* for the definition of `function`.
|
||||
|
||||
- `element``/``function`
|
||||
A file of zsh command text, taken to be the definition for
|
||||
`function`.
|
||||
`element`/`function`
|
||||
A file of zsh command text, taken to be the definition for `function`.
|
||||
|
||||
In summary, the order of searching is, first, in the *parents of*
|
||||
directories in `fpath` for the newer of either a compiled directory or a
|
||||
directory in `fpath`; second, if more than one of these contains a
|
||||
definition for the function that is sought, the leftmost in the `fpath`
|
||||
is chosen; and third, within a directory, the newer of either a compiled
|
||||
directories in fpath for the newer of either a compiled directory or a
|
||||
directory in fpath; second, if more than one of these contains a
|
||||
definition for the function that is sought, the leftmost in the fpath is
|
||||
chosen; and third, within a directory, the newer of either a compiled
|
||||
function or an ordinary function definition is used.
|
||||
|
||||
<span id="index-KSH_005fAUTOLOAD_002c-use-of"></span>
|
||||
|
||||
If the `KSH_AUTOLOAD` option is set, or the file contains only a simple
|
||||
If the KSH_AUTOLOAD option is set, or the file contains only a simple
|
||||
definition of the function, the file’s contents will be executed. This
|
||||
will normally define the function in question, but may also perform
|
||||
initialization, which is executed in the context of the function
|
||||
execution, and may therefore define local parameters. It is an error if
|
||||
the function is not defined by loading the file.
|
||||
|
||||
Otherwise, the function body (with no surrounding ‘`funcname``()
|
||||
{``...``}`’) is taken to be the complete contents of the file. This
|
||||
Otherwise, the function body (with no surrounding ‘`funcname`()
|
||||
{`...`}’) is taken to be the complete contents of the file. This
|
||||
processing of the file results in the function being re-defined, the
|
||||
function itself is not re-executed. To force the shell to perform
|
||||
initialization and then call the function defined, the file should
|
||||
@ -131,31 +129,31 @@ addition to a complete function definition (which will be retained for
|
||||
subsequent calls to the function), and a call to the shell function,
|
||||
including any arguments, at the end.
|
||||
|
||||
For example, suppose the autoload file `func` contains
|
||||
For example, suppose the autoload file func contains
|
||||
|
||||
<div class="example">
|
||||
|
||||
``` example
|
||||
```zsh
|
||||
func() { print This is func; }
|
||||
print func is initialized
|
||||
```
|
||||
|
||||
</div>
|
||||
|
||||
then ‘`func; func`’ with `KSH_AUTOLOAD` set will produce both messages
|
||||
on the first call, but only the message ‘`This is func`’ on the second
|
||||
and subsequent calls. Without `KSH_AUTOLOAD` set, it will produce the
|
||||
then ‘func; func’ with KSH_AUTOLOAD set will produce both messages on
|
||||
the first call, but only the message ‘This is func’ on the second and
|
||||
subsequent calls. Without KSH_AUTOLOAD set, it will produce the
|
||||
initialization message on the first call, and the other message on the
|
||||
second and subsequent calls.
|
||||
|
||||
It is also possible to create a function that is not marked as
|
||||
autoloaded, but which loads its own definition by searching `fpath`, by
|
||||
using ‘`autoload -X`’ within a shell function. For example, the
|
||||
following are equivalent:
|
||||
autoloaded, but which loads its own definition by searching fpath, by
|
||||
using ‘autoload -X’ within a shell function. For example, the following
|
||||
are equivalent:
|
||||
|
||||
<div class="example">
|
||||
|
||||
``` example
|
||||
```zsh
|
||||
myfunc() {
|
||||
autoload -X
|
||||
}
|
||||
@ -168,7 +166,7 @@ and
|
||||
|
||||
<div class="example">
|
||||
|
||||
``` example
|
||||
```zsh
|
||||
unfunction myfunc # if myfunc was defined
|
||||
autoload myfunc
|
||||
myfunc args...
|
||||
@ -176,53 +174,52 @@ myfunc args...
|
||||
|
||||
</div>
|
||||
|
||||
In fact, the `functions` command outputs ‘`builtin autoload -X`’ as the
|
||||
body of an autoloaded function. This is done so that
|
||||
In fact, the functions command outputs ‘builtin autoload -X’ as the body
|
||||
of an autoloaded function. This is done so that
|
||||
|
||||
<div class="example">
|
||||
|
||||
``` example
|
||||
```zsh
|
||||
eval "$(functions)"
|
||||
```
|
||||
|
||||
</div>
|
||||
|
||||
produces a reasonable result. A true autoloaded function can be
|
||||
identified by the presence of the comment ‘`# undefined`’ in the body,
|
||||
identified by the presence of the comment ‘# undefined’ in the body,
|
||||
because all comments are discarded from defined functions.
|
||||
|
||||
To load the definition of an autoloaded function `myfunc` without
|
||||
executing `myfunc`, use:
|
||||
To load the definition of an autoloaded function myfunc without
|
||||
executing myfunc, use:
|
||||
|
||||
<div class="example">
|
||||
|
||||
``` example
|
||||
```zsh
|
||||
autoload +X myfunc
|
||||
```
|
||||
|
||||
</div>
|
||||
|
||||
-----
|
||||
------------------------------------------------------------------------
|
||||
|
||||
<span id="Anonymous-Functions"></span>
|
||||
|
||||
## 9.2 Anonymous Functions
|
||||
|
||||
<span id="index-anonymous-functions"></span>
|
||||
<span id="index-functions_002c-anonymous"></span>
|
||||
<span id="index-anonymous-functions"></span> <span
|
||||
id="index-functions_002c-anonymous"></span>
|
||||
|
||||
If no name is given for a function, it is ‘anonymous’ and is handled
|
||||
specially. Either form of function definition may be used: a ‘`()`’ with
|
||||
no preceding name, or a ‘`function`’ with an immediately following open
|
||||
specially. Either form of function definition may be used: a ‘()’ with
|
||||
no preceding name, or a ‘function’ with an immediately following open
|
||||
brace. The function is executed immediately at the point of definition
|
||||
and is not stored for future use. The function name is set to
|
||||
‘`(anon)`’.
|
||||
and is not stored for future use. The function name is set to ‘(anon)’.
|
||||
|
||||
Arguments to the function may be specified as words following the
|
||||
closing brace defining the function, hence if there are none no
|
||||
arguments (other than `$0`) are set. This is a difference from the way
|
||||
arguments (other than $0) are set. This is a difference from the way
|
||||
other functions are parsed: normal function definitions may be followed
|
||||
by certain keywords such as ‘`else`’ or ‘`fi`’, which will be treated as
|
||||
by certain keywords such as ‘else’ or ‘fi’, which will be treated as
|
||||
arguments to anonymous functions, so that a newline or semicolon is
|
||||
needed to force keyword interpretation.
|
||||
|
||||
@ -240,7 +237,7 @@ For example,
|
||||
|
||||
<div class="example">
|
||||
|
||||
``` example
|
||||
```zsh
|
||||
variable=outside
|
||||
function {
|
||||
local variable=inside
|
||||
@ -255,7 +252,7 @@ outputs the following:
|
||||
|
||||
<div class="example">
|
||||
|
||||
``` example
|
||||
```zsh
|
||||
I am inside with arguments this and that
|
||||
I am outside
|
||||
```
|
||||
@ -263,11 +260,11 @@ I am outside
|
||||
</div>
|
||||
|
||||
Note that function definitions with arguments that expand to nothing,
|
||||
for example ‘` name=; function $name { ``...`` } `’, are not treated
|
||||
as anonymous functions. Instead, they are treated as normal function
|
||||
for example ‘name=; function $name { `...` }’, are not treated as
|
||||
anonymous functions. Instead, they are treated as normal function
|
||||
definitions where the definition is silently discarded.
|
||||
|
||||
-----
|
||||
------------------------------------------------------------------------
|
||||
|
||||
<span id="Special-Functions"></span>
|
||||
|
||||
@ -275,63 +272,63 @@ definitions where the definition is silently discarded.
|
||||
|
||||
Certain functions, if defined, have special meaning to the shell.
|
||||
|
||||
-----
|
||||
------------------------------------------------------------------------
|
||||
|
||||
<span id="Hook-Functions"></span>
|
||||
|
||||
### 9.3.1 Hook Functions
|
||||
|
||||
<span id="index-functions_002c-hook"></span>
|
||||
<span id="index-hook-functions"></span>
|
||||
<span id="index-functions_002c-hook"></span> <span
|
||||
id="index-hook-functions"></span>
|
||||
|
||||
For the functions below, it is possible to define an array that has the
|
||||
same name as the function with ‘`_functions`’ appended. Any element in
|
||||
same name as the function with ‘\_functions’ appended. Any element in
|
||||
such an array is taken as the name of a function to execute; it is
|
||||
executed in the same context and with the same arguments as the basic
|
||||
function. For example, if `$chpwd_functions` is an array containing the
|
||||
values ‘`mychpwd`’, ‘`chpwd_save_dirstack`’, then the shell attempts to
|
||||
execute the functions ‘`chpwd`’, ‘`mychpwd`’ and
|
||||
‘`chpwd_save_dirstack`’, in that order. Any function that does not
|
||||
exist is silently ignored. A function found by this mechanism is
|
||||
referred to elsewhere as a ‘hook function’. An error in any function
|
||||
causes subsequent functions not to be run. Note further that an error in
|
||||
a `precmd` hook causes an immediately following `periodic` function not
|
||||
to run (though it may run at the next opportunity).
|
||||
executed in the same context and with the same arguments and same
|
||||
initial value of $? as the basic function. For example, if
|
||||
$chpwd_functions is an array containing the values ‘mychpwd’,
|
||||
‘chpwd_save_dirstack’, then the shell attempts to execute the functions
|
||||
‘chpwd’, ‘mychpwd’ and ‘chpwd_save_dirstack’, in that order. Any
|
||||
function that does not exist is silently ignored. A function found by
|
||||
this mechanism is referred to elsewhere as a *hook function*. An error
|
||||
in any function causes subsequent functions not to be run. Note further
|
||||
that an error in a precmd hook causes an immediately following periodic
|
||||
function not to run (though it may run at the next opportunity).
|
||||
|
||||
<span id="index-chpwd"></span>
|
||||
<span id="index-chpwd_005ffunctions"></span>
|
||||
<span id="index-chpwd"></span> <span
|
||||
id="index-chpwd_005ffunctions"></span>
|
||||
|
||||
`chpwd`
|
||||
chpwd
|
||||
|
||||
Executed whenever the current working directory is changed.
|
||||
|
||||
<span id="index-periodic"></span>
|
||||
<span id="index-periodic_005ffunctions"></span>
|
||||
<span id="index-periodic"></span> <span
|
||||
id="index-periodic_005ffunctions"></span>
|
||||
|
||||
`periodic`
|
||||
periodic
|
||||
|
||||
<span id="index-PERIOD"></span>
|
||||
|
||||
If the parameter `PERIOD` is set, this function is executed every
|
||||
`$PERIOD` seconds, just before a prompt. Note that if multiple functions
|
||||
are defined using the array `periodic_functions` only one period is
|
||||
applied to the complete set of functions, and the scheduled time is not
|
||||
reset if the list of functions is altered. Hence the set of functions is
|
||||
always called together.
|
||||
If the parameter PERIOD is set, this function is executed every $PERIOD
|
||||
seconds, just before a prompt. Note that if multiple functions are
|
||||
defined using the array periodic_functions only one period is applied to
|
||||
the complete set of functions, and the scheduled time is not reset if
|
||||
the list of functions is altered. Hence the set of functions is always
|
||||
called together.
|
||||
|
||||
<span id="index-precmd"></span>
|
||||
<span id="index-precmd_005ffunctions"></span>
|
||||
<span id="index-precmd"></span> <span
|
||||
id="index-precmd_005ffunctions"></span>
|
||||
|
||||
`precmd`
|
||||
precmd
|
||||
|
||||
Executed before each prompt. Note that precommand functions are not
|
||||
re-executed simply because the command line is redrawn, as happens, for
|
||||
example, when a notification about an exiting job is displayed.
|
||||
|
||||
<span id="index-preexec"></span>
|
||||
<span id="index-preexec_005ffunctions"></span>
|
||||
<span id="index-preexec"></span> <span
|
||||
id="index-preexec_005ffunctions"></span>
|
||||
|
||||
`preexec`
|
||||
preexec
|
||||
|
||||
Executed just after a command has been read and is about to be executed.
|
||||
If the history mechanism is active (regardless of whether the line was
|
||||
@ -343,10 +340,10 @@ size-limited version of the command (with things like function bodies
|
||||
elided); the third argument contains the full text that is being
|
||||
executed.
|
||||
|
||||
<span id="index-zshaddhistory"></span>
|
||||
<span id="index-zshaddhistory_005ffunctions"></span>
|
||||
<span id="index-zshaddhistory"></span> <span
|
||||
id="index-zshaddhistory_005ffunctions"></span>
|
||||
|
||||
`zshaddhistory`
|
||||
zshaddhistory
|
||||
|
||||
<span id="index-history_002c-hook-when-line-is-saved"></span>
|
||||
|
||||
@ -364,14 +361,14 @@ If any of the hook functions returns status 2 the history line will be
|
||||
saved on the internal history list, but not written to the history file.
|
||||
In case of a conflict, the first non-zero status value is taken.
|
||||
|
||||
A hook function may call ‘`fc -p` `...`’ to switch the history context
|
||||
so that the history is saved in a different file from the that in the
|
||||
global `HISTFILE` parameter. This is handled specially: the history
|
||||
context is automatically restored after the processing of the history
|
||||
line is finished.
|
||||
A hook function may call ‘fc -p `...`’ to switch the history context so
|
||||
that the history is saved in a different file from that in the global
|
||||
HISTFILE parameter. This is handled specially: the history context is
|
||||
automatically restored after the processing of the history line is
|
||||
finished.
|
||||
|
||||
The following example function works with one of the options
|
||||
`INC_APPEND_HISTORY` or `SHARE_HISTORY` set, in order that the line is
|
||||
INC_APPEND_HISTORY or SHARE_HISTORY set, in order that the line is
|
||||
written out immediately after the history entry is added. It first adds
|
||||
the history line to the normal history with the newline stripped, which
|
||||
is usually the correct behaviour. Then it switches the history context
|
||||
@ -380,7 +377,7 @@ directory.
|
||||
|
||||
<div class="example">
|
||||
|
||||
``` example
|
||||
```zsh
|
||||
zshaddhistory() {
|
||||
print -sr -- ${1%%$'\n'}
|
||||
fc -p .zsh_local_history
|
||||
@ -389,17 +386,17 @@ zshaddhistory() {
|
||||
|
||||
</div>
|
||||
|
||||
<span id="index-zshexit"></span>
|
||||
<span id="index-zshexit_005ffunctions"></span>
|
||||
<span id="index-zshexit"></span> <span
|
||||
id="index-zshexit_005ffunctions"></span>
|
||||
|
||||
`zshexit`
|
||||
zshexit
|
||||
|
||||
Executed at the point where the main shell is about to exit normally.
|
||||
This is not called by exiting subshells, nor when the `exec` precommand
|
||||
modifier is used before an external command. Also, unlike `TRAPEXIT`, it
|
||||
This is not called by exiting subshells, nor when the exec precommand
|
||||
modifier is used before an external command. Also, unlike TRAPEXIT, it
|
||||
is not called when functions exit.
|
||||
|
||||
-----
|
||||
------------------------------------------------------------------------
|
||||
|
||||
<span id="Trap-Functions"></span>
|
||||
|
||||
@ -408,80 +405,78 @@ is not called when functions exit.
|
||||
The functions below are treated specially but do not have corresponding
|
||||
hook arrays.
|
||||
|
||||
- `TRAP``NAL`
|
||||
<span id="index-signals_002c-trapping"></span>
|
||||
<span id="index-trapping-signals"></span>
|
||||
TRAP`NAL`
|
||||
<span id="index-signals_002c-trapping"></span> <span
|
||||
id="index-trapping-signals"></span>
|
||||
|
||||
If defined and non-null, this function will be executed whenever the
|
||||
shell catches a signal `SIG``NAL`, where `NAL` is a signal name as
|
||||
specified for the `kill` builtin. The signal number will be passed
|
||||
as the first parameter to the function.
|
||||
If defined and non-null, this function will be executed whenever the
|
||||
shell catches a signal SIG`NAL`, where `NAL` is a signal name as
|
||||
specified for the kill builtin. The signal number will be passed as the
|
||||
first parameter to the function.
|
||||
|
||||
If a function of this form is defined and null, the shell and
|
||||
processes spawned by it will ignore `SIG``NAL`.
|
||||
If a function of this form is defined and null, the shell and processes
|
||||
spawned by it will ignore SIG`NAL`.
|
||||
|
||||
The return status from the function is handled specially. If it is
|
||||
zero, the signal is assumed to have been handled, and execution
|
||||
continues normally. Otherwise, the shell will behave as interrupted
|
||||
except that the return status of the trap is retained.
|
||||
The return status from the function is handled specially. If it is zero,
|
||||
the signal is assumed to have been handled, and execution continues
|
||||
normally. Otherwise, the shell will behave as interrupted except that
|
||||
the return status of the trap is retained.
|
||||
|
||||
Programs terminated by uncaught signals typically return the status
|
||||
128 plus the signal number. Hence the following causes the handler
|
||||
for `SIGINT` to print a message, then mimic the usual effect of the
|
||||
signal.
|
||||
Programs terminated by uncaught signals typically return the status 128
|
||||
plus the signal number. Hence the following causes the handler for
|
||||
SIGINT to print a message, then mimic the usual effect of the signal.
|
||||
|
||||
<div class="example">
|
||||
<div class="example">
|
||||
|
||||
``` example
|
||||
TRAPINT() {
|
||||
```zsh
|
||||
TRAPINT() {
|
||||
print "Caught SIGINT, aborting."
|
||||
return $(( 128 + $1 ))
|
||||
}
|
||||
```
|
||||
}
|
||||
```
|
||||
|
||||
</div>
|
||||
</div>
|
||||
|
||||
The functions `TRAPZERR`, `TRAPDEBUG` and `TRAPEXIT` are never
|
||||
executed inside other traps.
|
||||
The functions TRAPZERR, TRAPDEBUG and TRAPEXIT are never executed inside
|
||||
other traps.
|
||||
|
||||
<span id="index-TRAPDEBUG"></span>
|
||||
<span id="index-TRAPDEBUG"></span>
|
||||
|
||||
- `TRAPDEBUG`
|
||||
If the option `DEBUG_BEFORE_CMD` is set (as it is by default),
|
||||
executed before each command; otherwise executed after each command.
|
||||
See the description of the `trap` builtin in [Shell Builtin
|
||||
Commands](Shell-Builtin-Commands.html#Shell-Builtin-Commands) for
|
||||
details of additional features provided in debug traps.
|
||||
TRAPDEBUG
|
||||
If the option DEBUG_BEFORE_CMD is set (as it is by default), executed
|
||||
before each command; otherwise executed after each command. See the
|
||||
description of the trap builtin in [Shell Builtin
|
||||
Commands](Shell-Builtin-Commands.html#Shell-Builtin-Commands) for
|
||||
details of additional features provided in debug traps.
|
||||
|
||||
<span id="index-TRAPEXIT"></span>
|
||||
<span id="index-TRAPEXIT"></span>
|
||||
|
||||
- `TRAPEXIT`
|
||||
Executed when the shell exits, or when the current function exits if
|
||||
defined inside a function. The value of `$?` at the start of
|
||||
execution is the exit status of the shell or the return status of
|
||||
the function exiting.
|
||||
TRAPEXIT
|
||||
Executed when the shell exits, or when the current function exits if
|
||||
defined inside a function. The value of $? at the start of execution is
|
||||
the exit status of the shell or the return status of the function
|
||||
exiting.
|
||||
|
||||
<span id="index-TRAPZERR"></span> <span id="index-TRAPERR"></span>
|
||||
<span id="index-TRAPZERR"></span> <span id="index-TRAPERR"></span>
|
||||
|
||||
- `TRAPZERR`
|
||||
Executed whenever a command has a non-zero exit status. However, the
|
||||
function is not executed if the command occurred in a sublist
|
||||
followed by ‘`&&`’ or ‘`||`’; only the final command in a sublist of
|
||||
this type causes the trap to be executed. The function `TRAPERR`
|
||||
acts the same as `TRAPZERR` on systems where there is no `SIGERR`
|
||||
(this is the usual case).
|
||||
TRAPZERR
|
||||
Executed whenever a command has a non-zero exit status. However, the
|
||||
function is not executed if the command occurred in a sublist followed
|
||||
by ‘&&’ or ‘\|\|’; only the final command in a sublist of this type
|
||||
causes the trap to be executed. The function TRAPERR acts the same as
|
||||
TRAPZERR on systems where there is no SIGERR (this is the usual case).
|
||||
|
||||
<span id="index-trap_002c-use-of"></span>
|
||||
|
||||
The functions beginning ‘`TRAP`’ may alternatively be defined with the
|
||||
`trap` builtin: this may be preferable for some uses. Setting a trap
|
||||
with one form removes any trap of the other form for the same signal;
|
||||
The functions beginning ‘TRAP’ may alternatively be defined with the
|
||||
trap builtin: this may be preferable for some uses. Setting a trap with
|
||||
one form removes any trap of the other form for the same signal;
|
||||
removing a trap in either form removes all traps for the same signal.
|
||||
The forms
|
||||
|
||||
<div class="example">
|
||||
|
||||
``` example
|
||||
```zsh
|
||||
TRAPNAL() {
|
||||
# code
|
||||
}
|
||||
@ -493,7 +488,7 @@ TRAPNAL() {
|
||||
|
||||
<div class="example">
|
||||
|
||||
``` example
|
||||
```zsh
|
||||
trap '
|
||||
# code
|
||||
' NAL
|
||||
@ -504,19 +499,19 @@ trap '
|
||||
(’list traps’) are equivalent in most ways, the exceptions being the
|
||||
following:
|
||||
|
||||
- Function traps have all the properties of normal functions,
|
||||
- Function traps have all the properties of normal functions,
|
||||
appearing in the list of functions and being called with their own
|
||||
function context rather than the context where the trap was
|
||||
triggered.
|
||||
- The return status from function traps is special, whereas a return
|
||||
- The return status from function traps is special, whereas a return
|
||||
from a list trap causes the surrounding context to return with the
|
||||
given status.
|
||||
- Function traps are not reset within subshells, in accordance with
|
||||
- Function traps are not reset within subshells, in accordance with
|
||||
zsh behaviour; list traps are reset, in accordance with POSIX
|
||||
behaviour.
|
||||
|
||||
-----
|
||||
------------------------------------------------------------------------
|
||||
|
||||
This document was generated on *February 15, 2020* using
|
||||
[*texi2html 5.0*](http://www.nongnu.org/texi2html/).
|
||||
Zsh version 5.8, released on February 14, 2020.
|
||||
This document was generated on *May 14, 2022* using [*texi2html
|
||||
5.0*](http://www.nongnu.org/texi2html/).
|
||||
Zsh version 5.9, released on May 14, 2022.
|
||||
|
||||
@ -30,7 +30,7 @@ Zsh has command line editing, builtin spelling correction, programmable
|
||||
command completion, shell functions (with autoloading), a history
|
||||
mechanism, and a host of other features.
|
||||
|
||||
-----
|
||||
------------------------------------------------------------------------
|
||||
|
||||
<span id="Author"></span> <span id="Author-1"></span>
|
||||
|
||||
@ -38,14 +38,13 @@ mechanism, and a host of other features.
|
||||
|
||||
<span id="index-author"></span>
|
||||
|
||||
Zsh was originally written by Paul Falstad `<pf@zsh.org>`. Zsh is now
|
||||
maintained by the members of the zsh-workers mailing list
|
||||
`<zsh-workers@zsh.org>`. The development is currently coordinated by
|
||||
Peter Stephenson `<pws@zsh.org>`. The coordinator can be contacted at
|
||||
`<coordinator@zsh.org>`, but matters relating to the code should
|
||||
generally go to the mailing list.
|
||||
Zsh was originally written by Paul Falstad. Zsh is now maintained by the
|
||||
members of the zsh-workers mailing list \<zsh-workers@zsh.org>. The
|
||||
development is currently coordinated by Peter Stephenson \<pws@zsh.org>.
|
||||
The coordinator can be contacted at \<coordinator@zsh.org>, but matters
|
||||
relating to the code should generally go to the mailing list.
|
||||
|
||||
-----
|
||||
------------------------------------------------------------------------
|
||||
|
||||
<span id="Availability"></span> <span id="Availability-1"></span>
|
||||
|
||||
@ -53,19 +52,19 @@ generally go to the mailing list.
|
||||
|
||||
Zsh is available from the following HTTP and anonymous FTP site.
|
||||
|
||||
<span id="index-FTP-sites-for-zsh"></span>
|
||||
<span id="index-acquiring-zsh-by-FTP"></span>
|
||||
<span id="index-availability-of-zsh"></span>
|
||||
<span id="index-FTP-sites-for-zsh"></span> <span
|
||||
id="index-acquiring-zsh-by-FTP"></span> <span
|
||||
id="index-availability-of-zsh"></span>
|
||||
|
||||
`ftp://ftp.zsh.org/pub/`
|
||||
`https://www.zsh.org/pub/` )
|
||||
<ftp://ftp.zsh.org/pub/>
|
||||
<https://www.zsh.org/pub/>
|
||||
|
||||
The up-to-date source code is available via Git from Sourceforge. See
|
||||
`https://sourceforge.net/projects/zsh/` for details. A summary of
|
||||
<https://sourceforge.net/projects/zsh/> for details. A summary of
|
||||
instructions for the archive can be found at
|
||||
`http://zsh.sourceforge.net/`.
|
||||
<https://zsh.sourceforge.io/>.
|
||||
|
||||
-----
|
||||
------------------------------------------------------------------------
|
||||
|
||||
<span id="Mailing-Lists"></span> <span id="Mailing-Lists-1"></span>
|
||||
|
||||
@ -73,32 +72,39 @@ instructions for the archive can be found at
|
||||
|
||||
<span id="index-mailing-lists"></span>
|
||||
|
||||
Zsh has 3 mailing lists:
|
||||
Zsh has several mailing lists:
|
||||
|
||||
- `<zsh-announce@zsh.org>`
|
||||
Announcements about releases, major changes in the shell and the
|
||||
monthly posting of the Zsh FAQ. (moderated)
|
||||
\<zsh-announce@zsh.org>
|
||||
Announcements about releases, major changes in the shell and the monthly
|
||||
posting of the Zsh FAQ. (moderated)
|
||||
|
||||
- `<zsh-users@zsh.org>`
|
||||
User discussions.
|
||||
\<zsh-users@zsh.org>
|
||||
User discussions.
|
||||
|
||||
- `<zsh-workers@zsh.org>`
|
||||
Hacking, development, bug reports and patches.
|
||||
\<zsh-workers@zsh.org>
|
||||
Hacking, development, bug reports and patches.
|
||||
|
||||
\<zsh-security@zsh.org>
|
||||
Private mailing list (the general public cannot subscribe to it) for
|
||||
discussing bug reports with security implications, i.e., potential
|
||||
vulnerabilities.
|
||||
|
||||
If you find a security problem in zsh itself, please mail this address.
|
||||
|
||||
To subscribe or unsubscribe, send mail to the associated administrative
|
||||
address for the mailing list.
|
||||
|
||||
`<zsh-announce-subscribe@zsh.org>`
|
||||
\<zsh-announce-subscribe@zsh.org>
|
||||
|
||||
`<zsh-users-subscribe@zsh.org>`
|
||||
\<zsh-users-subscribe@zsh.org>
|
||||
|
||||
`<zsh-workers-subscribe@zsh.org>`
|
||||
\<zsh-workers-subscribe@zsh.org>
|
||||
|
||||
`<zsh-announce-unsubscribe@zsh.org>`
|
||||
\<zsh-announce-unsubscribe@zsh.org>
|
||||
|
||||
`<zsh-users-unsubscribe@zsh.org>`
|
||||
\<zsh-users-unsubscribe@zsh.org>
|
||||
|
||||
`<zsh-workers-unsubscribe@zsh.org>`
|
||||
\<zsh-workers-unsubscribe@zsh.org>
|
||||
|
||||
|
||||
|
||||
@ -107,42 +113,39 @@ submissions to zsh-announce are automatically forwarded to zsh-users.
|
||||
All submissions to zsh-users are automatically forwarded to zsh-workers.
|
||||
|
||||
If you have problems subscribing/unsubscribing to any of the mailing
|
||||
lists, send mail to `<listmaster@zsh.org>`. The mailing lists are
|
||||
maintained by Karsten Thygesen `<karthy@kom.auc.dk>`.
|
||||
lists, send mail to \<listmaster@zsh.org>.
|
||||
|
||||
The mailing lists are archived; the archives can be accessed via the
|
||||
administrative addresses listed above. There is also a hypertext
|
||||
archive, maintained by Geoff Wing `<gcw@zsh.org>`, available at
|
||||
`https://www.zsh.org/mla/`.
|
||||
administrative addresses listed above. There is also a hypertext archive
|
||||
available at <https://www.zsh.org/mla/>.
|
||||
|
||||
-----
|
||||
------------------------------------------------------------------------
|
||||
|
||||
<span id="The-Zsh-FAQ"></span> <span id="The-Zsh-FAQ-1"></span>
|
||||
|
||||
## 2.4 The Zsh FAQ
|
||||
|
||||
Zsh has a list of Frequently Asked Questions (FAQ), maintained by Peter
|
||||
Stephenson `<pws@zsh.org>`. It is regularly posted to the newsgroup
|
||||
Stephenson \<pws@zsh.org>. It is regularly posted to the newsgroup
|
||||
comp.unix.shell and the zsh-announce mailing list. The latest version
|
||||
can be found at any of the Zsh FTP sites, or at
|
||||
`http://www.zsh.org/FAQ/`. The contact address for FAQ-related matters
|
||||
is `<faqmaster@zsh.org>`.
|
||||
<https://www.zsh.org/FAQ/>. The contact address for FAQ-related matters
|
||||
is \<faqmaster@zsh.org>.
|
||||
|
||||
-----
|
||||
------------------------------------------------------------------------
|
||||
|
||||
<span id="The-Zsh-Web-Page"></span>
|
||||
<span id="The-Zsh-Web-Page-1"></span>
|
||||
<span id="The-Zsh-Web-Page"></span> <span
|
||||
id="The-Zsh-Web-Page-1"></span>
|
||||
|
||||
## 2.5 The Zsh Web Page
|
||||
|
||||
Zsh has a web page which is located at `https://www.zsh.org/`. This is
|
||||
maintained by Karsten Thygesen `<karthy@zsh.org>`, of SunSITE Denmark.
|
||||
The contact address for web-related matters is `<webmaster@zsh.org>`.
|
||||
Zsh has a web page which is located at <https://www.zsh.org/>. The
|
||||
contact address for web-related matters is \<webmaster@zsh.org>.
|
||||
|
||||
-----
|
||||
------------------------------------------------------------------------
|
||||
|
||||
<span id="The-Zsh-Userguide"></span>
|
||||
<span id="The-Zsh-Userguide-1"></span>
|
||||
<span id="The-Zsh-Userguide"></span> <span
|
||||
id="The-Zsh-Userguide-1"></span>
|
||||
|
||||
## 2.6 The Zsh Userguide
|
||||
|
||||
@ -150,24 +153,23 @@ A userguide is currently in preparation. It is intended to complement
|
||||
the manual, with explanations and hints on issues where the manual can
|
||||
be cabbalistic, hierographic, or downright mystifying (for example, the
|
||||
word ‘hierographic’ does not exist). It can be viewed in its current
|
||||
state at `http://zsh.sourceforge.net/Guide/`. At the time of writing,
|
||||
state at <https://zsh.sourceforge.io/Guide/>. At the time of writing,
|
||||
chapters dealing with startup files and their contents and the new
|
||||
completion system were essentially complete.
|
||||
|
||||
-----
|
||||
------------------------------------------------------------------------
|
||||
|
||||
<span id="See-Also"></span> <span id="See-Also-1"></span>
|
||||
|
||||
## 2.7 See Also
|
||||
|
||||
man page sh(1), man page csh(1), man page tcsh(1), man page rc(1), man
|
||||
page bash(1), man page ksh(1)
|
||||
sh(1), csh(1), tcsh(1), rc(1), bash(1), ksh(1)
|
||||
|
||||
IEEE Standard for information Technology - Part 2: Shell and Utilities,
|
||||
IEEE Inc, 1993, ISBN 1-55937-255-9.
|
||||
|
||||
-----
|
||||
------------------------------------------------------------------------
|
||||
|
||||
This document was generated on *February 15, 2020* using
|
||||
[*texi2html 5.0*](http://www.nongnu.org/texi2html/).
|
||||
Zsh version 5.8, released on February 14, 2020.
|
||||
This document was generated on *May 14, 2022* using [*texi2html
|
||||
5.0*](http://www.nongnu.org/texi2html/).
|
||||
Zsh version 5.9, released on May 14, 2022.
|
||||
|
||||
@ -9,213 +9,212 @@
|
||||
|
||||
<!-- END doctoc generated TOC please keep comment here to allow auto update -->
|
||||
|
||||
<span id="Invocation"></span> <span id="Invocation-1"></span>
|
||||
<span id="Invocation"></span> <span id="Invocation-2"></span>
|
||||
|
||||
# 4 Invocation
|
||||
|
||||
<span id="index-invocation"></span>
|
||||
|
||||
-----
|
||||
------------------------------------------------------------------------
|
||||
|
||||
<span id="Invocation-2"></span>
|
||||
<span id="Invocation-1"></span>
|
||||
|
||||
## 4.1 Invocation
|
||||
|
||||
<span id="index-shell-options"></span>
|
||||
<span id="index-options_002c-shell"></span>
|
||||
<span id="index-shell-flags"></span>
|
||||
<span id="index-flags_002c-shell"></span>
|
||||
<span id="index-shell-options"></span> <span
|
||||
id="index-options_002c-shell"></span> <span
|
||||
id="index-shell-flags"></span> <span id="index-flags_002c-shell"></span>
|
||||
|
||||
The following flags are interpreted by the shell when invoked to
|
||||
determine where the shell will read commands from:
|
||||
|
||||
- `-c`
|
||||
Take the first argument as a command to execute, rather than reading
|
||||
commands from a script or standard input. If any further arguments
|
||||
are given, the first one is assigned to `$0`, rather than being used
|
||||
as a positional parameter.
|
||||
-c
|
||||
Take the first argument as a command to execute, rather than reading
|
||||
commands from a script or standard input. If any further arguments are
|
||||
given, the first one is assigned to $0, rather than being used as a
|
||||
positional parameter.
|
||||
|
||||
- `-i`
|
||||
Force shell to be interactive. It is still possible to specify a
|
||||
script to execute.
|
||||
-i
|
||||
Force shell to be interactive. It is still possible to specify a script
|
||||
to execute.
|
||||
|
||||
- `-s`
|
||||
Force shell to read commands from the standard input. If the `-s`
|
||||
flag is not present and an argument is given, the first argument is
|
||||
taken to be the pathname of a script to execute.
|
||||
-s
|
||||
Force shell to read commands from the standard input. If the -s flag is
|
||||
not present and an argument is given, the first argument is taken to be
|
||||
the pathname of a script to execute.
|
||||
|
||||
If there are any remaining arguments after option processing, and
|
||||
neither of the options `-c` or `-s` was supplied, the first argument is
|
||||
neither of the options -c or -s was supplied, the first argument is
|
||||
taken as the file name of a script containing shell commands to be
|
||||
executed. If the option `PATH_SCRIPT` is set, and the file name does not
|
||||
contain a directory path (i.e. there is no ‘`/`’ in the name), first the
|
||||
current directory and then the command path given by the variable `PATH`
|
||||
executed. If the option PATH_SCRIPT is set, and the file name does not
|
||||
contain a directory path (i.e. there is no ‘/’ in the name), first the
|
||||
current directory and then the command path given by the variable PATH
|
||||
are searched for the script. If the option is not set or the file name
|
||||
contains a ‘`/`’ it is used directly.
|
||||
contains a ‘/’ it is used directly.
|
||||
|
||||
After the first one or two arguments have been appropriated as described
|
||||
above, the remaining arguments are assigned to the positional
|
||||
parameters.
|
||||
|
||||
For further options, which are common to invocation and the `set`
|
||||
builtin, see [Options](Options.html#Options).
|
||||
For further options, which are common to invocation and the set builtin,
|
||||
see [Options](Options.html#Options).
|
||||
|
||||
The long option ‘`-``-emulate`’ followed (in a separate word) by an
|
||||
The long option ‘--emulate’ followed (in a separate word) by an
|
||||
emulation mode may be passed to the shell. The emulation modes are those
|
||||
described for the `emulate` builtin, see [Shell Builtin
|
||||
described for the emulate builtin, see [Shell Builtin
|
||||
Commands](Shell-Builtin-Commands.html#Shell-Builtin-Commands). The
|
||||
‘`-``-emulate`’ option must precede any other options (which might
|
||||
otherwise be overridden), but following options are honoured, so may be
|
||||
used to modify the requested emulation mode. Note that certain extra
|
||||
steps are taken to ensure a smooth emulation when this option is used
|
||||
compared with the `emulate` command within the shell: for example,
|
||||
variables that conflict with POSIX usage such as `path` are not defined
|
||||
within the shell.
|
||||
‘--emulate’ option must precede any other options (which might otherwise
|
||||
be overridden), but following options are honoured, so may be used to
|
||||
modify the requested emulation mode. Note that certain extra steps are
|
||||
taken to ensure a smooth emulation when this option is used compared
|
||||
with the emulate command within the shell: for example, variables that
|
||||
conflict with POSIX usage such as path are not defined within the shell.
|
||||
|
||||
Options may be specified by name using the `-o` option. `-o` acts like a
|
||||
Options may be specified by name using the -o option. -o acts like a
|
||||
single-letter option, but takes a following string as the option name.
|
||||
For example,
|
||||
|
||||
<div class="example">
|
||||
|
||||
``` example
|
||||
```zsh
|
||||
zsh -x -o shwordsplit scr
|
||||
```
|
||||
|
||||
</div>
|
||||
|
||||
runs the script `scr`, setting the `XTRACE` option by the corresponding
|
||||
letter ‘`-x`’ and the `SH_WORD_SPLIT` option by name. Options may be
|
||||
turned *off* by name by using `+o` instead of `-o`. `-o` can be stacked
|
||||
up with preceding single-letter options, so for example ‘`-xo
|
||||
shwordsplit`’ or ‘`-xoshwordsplit`’ is equivalent to ‘`-x -o
|
||||
shwordsplit`’.
|
||||
runs the script scr, setting the XTRACE option by the corresponding
|
||||
letter ‘-x’ and the SH_WORD_SPLIT option by name. Options may be turned
|
||||
*off* by name by using +o instead of -o. -o can be stacked up with
|
||||
preceding single-letter options, so for example ‘-xo shwordsplit’ or
|
||||
‘-xoshwordsplit’ is equivalent to ‘-x -o shwordsplit’.
|
||||
|
||||
<span id="index-long-option"></span>
|
||||
|
||||
Options may also be specified by name in GNU long option style,
|
||||
‘`-``-``option-name`’. When this is done, ‘`-`’ characters in the
|
||||
option name are permitted: they are translated into ‘`_`’, and thus
|
||||
ignored. So, for example, ‘`zsh -``-sh-word-split`’ invokes zsh with the
|
||||
`SH_WORD_SPLIT` option turned on. Like other option syntaxes, options
|
||||
can be turned off by replacing the initial ‘`-`’ with a ‘`+`’; thus
|
||||
‘`+-sh-word-split`’ is equivalent to ‘`-``-no-sh-word-split`’. Unlike
|
||||
other option syntaxes, GNU-style long options cannot be stacked with any
|
||||
other options, so for example ‘`-x-shwordsplit`’ is an error, rather
|
||||
than being treated like ‘`-x -``-shwordsplit`’.
|
||||
‘--`option-name`’. When this is done, ‘-’ characters in the option name
|
||||
are permitted: they are translated into ‘\_’, and thus ignored. So, for
|
||||
example, ‘zsh --sh-word-split’ invokes zsh with the SH_WORD_SPLIT option
|
||||
turned on. Like other option syntaxes, options can be turned off by
|
||||
replacing the initial ‘-’ with a ‘+’; thus ‘+-sh-word-split’ is
|
||||
equivalent to ‘--no-sh-word-split’. Unlike other option syntaxes,
|
||||
GNU-style long options cannot be stacked with any other options, so for
|
||||
example ‘-x-shwordsplit’ is an error, rather than being treated like ‘-x
|
||||
--shwordsplit’.
|
||||
|
||||
<span id="index-_002d_002dversion"></span>
|
||||
<span id="index-_002d_002dhelp"></span>
|
||||
<span id="index-_002d_002dversion"></span> <span
|
||||
id="index-_002d_002dhelp"></span>
|
||||
|
||||
The special GNU-style option ‘`-``-version`’ is handled; it sends to
|
||||
The special GNU-style option ‘--version’ is handled; it sends to
|
||||
standard output the shell’s version information, then exits
|
||||
successfully. ‘`-``-help`’ is also handled; it sends to standard output
|
||||
a list of options that can be used when invoking the shell, then exits
|
||||
successfully. ‘--help’ is also handled; it sends to standard output a
|
||||
list of options that can be used when invoking the shell, then exits
|
||||
successfully.
|
||||
|
||||
Option processing may be finished, allowing following arguments that
|
||||
start with ‘`-`’ or ‘`+`’ to be treated as normal arguments, in two
|
||||
ways. Firstly, a lone ‘`-`’ (or ‘`+`’) as an argument by itself ends
|
||||
option processing. Secondly, a special option ‘`-``-`’ (or ‘`+-`’),
|
||||
which may be specified on its own (which is the standard POSIX usage) or
|
||||
may be stacked with preceding options (so ‘`-x-`’ is equivalent to ‘`-x
|
||||
-``-`’). Options are not permitted to be stacked after ‘`-``-`’ (so
|
||||
‘`-x-f`’ is an error), but note the GNU-style option form discussed
|
||||
above, where ‘`-``-shwordsplit`’ is permitted and does not end option
|
||||
processing.
|
||||
start with ‘-’ or ‘+’ to be treated as normal arguments, in two ways.
|
||||
Firstly, a lone ‘-’ (or ‘+’) as an argument by itself ends option
|
||||
processing. Secondly, a special option ‘--’ (or ‘+-’), which may be
|
||||
specified on its own (which is the standard POSIX usage) or may be
|
||||
stacked with preceding options (so ‘-x-’ is equivalent to ‘-x --’).
|
||||
Options are not permitted to be stacked after ‘--’ (so ‘-x-f’ is an
|
||||
error), but note the GNU-style option form discussed above, where
|
||||
‘--shwordsplit’ is permitted and does not end option processing.
|
||||
|
||||
Except when the sh/ksh emulation single-letter options are in effect,
|
||||
the option ‘`-b`’ (or ‘`+b`’) ends option processing. ‘`-b`’ is like
|
||||
‘`-``-`’, except that further single-letter options can be stacked
|
||||
after the ‘`-b`’ and will take effect as normal.
|
||||
the option ‘-b’ (or ‘+b’) ends option processing. ‘-b’ is like ‘--’,
|
||||
except that further single-letter options can be stacked after the ‘-b’
|
||||
and will take effect as normal.
|
||||
|
||||
-----
|
||||
------------------------------------------------------------------------
|
||||
|
||||
<span id="Compatibility"></span> <span id="Compatibility-1"></span>
|
||||
|
||||
## 4.2 Compatibility
|
||||
|
||||
<span id="index-compatibility"></span>
|
||||
<span id="index-sh-compatibility"></span>
|
||||
<span id="index-ksh-compatibility"></span>
|
||||
<span id="index-compatibility"></span> <span
|
||||
id="index-sh-compatibility"></span> <span
|
||||
id="index-ksh-compatibility"></span>
|
||||
|
||||
Zsh tries to emulate sh or ksh when it is invoked as `sh` or `ksh`
|
||||
Zsh tries to emulate sh or ksh when it is invoked as sh or ksh
|
||||
respectively; more precisely, it looks at the first letter of the name
|
||||
by which it was invoked, excluding any initial ‘`r`’ (assumed to stand
|
||||
for ‘restricted’), and if that is ‘`b`’, ‘`s`’ or ‘`k`’ it will emulate
|
||||
sh or ksh. Furthermore, if invoked as `su` (which happens on certain
|
||||
systems when the shell is executed by the `su` command), the shell will
|
||||
try to find an alternative name from the `SHELL` environment variable
|
||||
and perform emulation based on that.
|
||||
by which it was invoked, excluding any initial ‘r’ (assumed to stand for
|
||||
‘restricted’), and if that is ‘b’, ‘s’ or ‘k’ it will emulate sh or ksh.
|
||||
Furthermore, if invoked as su (which happens on certain systems when the
|
||||
shell is executed by the su command), the shell will try to find an
|
||||
alternative name from the SHELL environment variable and perform
|
||||
emulation based on that.
|
||||
|
||||
In sh and ksh compatibility modes the following parameters are not
|
||||
special and not initialized by the shell: `ARGC`, `argv`, `cdpath`,
|
||||
`fignore`, `fpath`, `HISTCHARS`, `mailpath`, `MANPATH`, `manpath`,
|
||||
`path`, `prompt`, `PROMPT`, `PROMPT2`, `PROMPT3`, `PROMPT4`, `psvar`,
|
||||
`status`, `watch`.
|
||||
special and not initialized by the shell: ARGC, argv, cdpath, fignore,
|
||||
fpath, HISTCHARS, mailpath, MANPATH, manpath, path, prompt, PROMPT,
|
||||
PROMPT2, PROMPT3, PROMPT4, psvar, status.
|
||||
|
||||
<span id="index-ENV_002c-use-of"></span>
|
||||
|
||||
The usual zsh startup/shutdown scripts are not executed. Login shells
|
||||
source `/etc/profile` followed by `$HOME/.profile`. If the `ENV`
|
||||
environment variable is set on invocation, `$ENV` is sourced after the
|
||||
profile scripts. The value of `ENV` is subjected to parameter expansion,
|
||||
command substitution, and arithmetic expansion before being interpreted
|
||||
as a pathname. Note that the `PRIVILEGED` option also affects the
|
||||
execution of startup files.
|
||||
source /etc/profile followed by $HOME/.profile. If the ENV environment
|
||||
variable is set on invocation, $ENV is sourced after the profile
|
||||
scripts. The value of ENV is subjected to parameter expansion, command
|
||||
substitution, and arithmetic expansion before being interpreted as a
|
||||
pathname. Note that the PRIVILEGED option also affects the execution of
|
||||
startup files.
|
||||
|
||||
The following options are set if the shell is invoked as `sh` or `ksh`:
|
||||
`NO_BAD_PATTERN`, `NO_BANG_HIST`, `NO_BG_NICE`, `NO_EQUALS`,
|
||||
`NO_FUNCTION_ARGZERO`, `GLOB_SUBST`, `NO_GLOBAL_EXPORT`, `NO_HUP`,
|
||||
`INTERACTIVE_COMMENTS`, `KSH_ARRAYS`, `NO_MULTIOS`, `NO_NOMATCH`,
|
||||
`NO_NOTIFY`, `POSIX_BUILTINS`, `NO_PROMPT_PERCENT`, `RM_STAR_SILENT`,
|
||||
`SH_FILE_EXPANSION`, `SH_GLOB`, `SH_OPTION_LETTERS`, `SH_WORD_SPLIT`.
|
||||
Additionally the `BSD_ECHO` and `IGNORE_BRACES` options are set if zsh
|
||||
is invoked as `sh`. Also, the `KSH_OPTION_PRINT`, `LOCAL_OPTIONS`,
|
||||
`PROMPT_BANG`, `PROMPT_SUBST` and `SINGLE_LINE_ZLE` options are set if
|
||||
zsh is invoked as `ksh`.
|
||||
The following options are set if the shell is invoked as sh or ksh:
|
||||
NO_BAD_PATTERN, NO_BANG_HIST, NO_BG_NICE, NO_EQUALS,
|
||||
NO_FUNCTION_ARGZERO, GLOB_SUBST, NO_GLOBAL_EXPORT, NO_HUP,
|
||||
INTERACTIVE_COMMENTS, KSH_ARRAYS, NO_MULTIOS, NO_NOMATCH, NO_NOTIFY,
|
||||
POSIX_BUILTINS, NO_PROMPT_PERCENT, RM_STAR_SILENT, SH_FILE_EXPANSION,
|
||||
SH_GLOB, SH_OPTION_LETTERS, SH_WORD_SPLIT. Additionally the BSD_ECHO and
|
||||
IGNORE_BRACES options are set if zsh is invoked as sh. Also, the
|
||||
KSH_OPTION_PRINT, LOCAL_OPTIONS, PROMPT_BANG, PROMPT_SUBST and
|
||||
SINGLE_LINE_ZLE options are set if zsh is invoked as ksh.
|
||||
|
||||
-----
|
||||
Please note that, whilst reasonable efforts are taken to address
|
||||
incompatibilities when they arise, zsh does not guarantee complete
|
||||
emulation of other shells, nor POSIX compliance. For more information on
|
||||
the differences between zsh and other shells, please refer to chapter 2
|
||||
of the shell FAQ, <https://www.zsh.org/FAQ/>.
|
||||
|
||||
<span id="Restricted-Shell"></span>
|
||||
<span id="Restricted-Shell-1"></span>
|
||||
------------------------------------------------------------------------
|
||||
|
||||
<span id="Restricted-Shell"></span> <span
|
||||
id="Restricted-Shell-1"></span>
|
||||
|
||||
## 4.3 Restricted Shell
|
||||
|
||||
<span id="index-restricted-shell"></span>
|
||||
<span id="index-RESTRICTED"></span>
|
||||
<span id="index-restricted-shell"></span> <span
|
||||
id="index-RESTRICTED"></span>
|
||||
|
||||
When the basename of the command used to invoke zsh starts with the
|
||||
letter ‘`r`’ or the ‘`-r`’ command line option is supplied at
|
||||
invocation, the shell becomes restricted. Emulation mode is determined
|
||||
after stripping the letter ‘`r`’ from the invocation name. The following
|
||||
are disabled in restricted mode:
|
||||
letter ‘r’ or the ‘-r’ command line option is supplied at invocation,
|
||||
the shell becomes restricted. Emulation mode is determined after
|
||||
stripping the letter ‘r’ from the invocation name. The following are
|
||||
disabled in restricted mode:
|
||||
|
||||
- changing directories with the `cd` builtin
|
||||
- changing or unsetting the `EGID`, `EUID`, `GID`, `HISTFILE`,
|
||||
`HISTSIZE`, `IFS`, `LD_AOUT_LIBRARY_PATH`, `LD_AOUT_PRELOAD`,
|
||||
`LD_LIBRARY_PATH`, `LD_PRELOAD`, `MODULE_PATH`, `module_path`,
|
||||
`PATH`, `path`, `SHELL`, `UID` and `USERNAME` parameters
|
||||
- specifying command names containing `/`
|
||||
- specifying command pathnames using `hash`
|
||||
- redirecting output to files
|
||||
- using the `exec` builtin command to replace the shell with another
|
||||
- changing directories with the cd builtin
|
||||
- changing or unsetting the EGID, EUID, GID, HISTFILE, HISTSIZE, IFS,
|
||||
LD_AOUT_LIBRARY_PATH, LD_AOUT_PRELOAD, LD_LIBRARY_PATH, LD_PRELOAD,
|
||||
MODULE_PATH, module_path, PATH, path, SHELL, UID and USERNAME
|
||||
parameters
|
||||
- specifying command names containing /
|
||||
- specifying command pathnames using hash
|
||||
- redirecting output to files
|
||||
- using the exec builtin command to replace the shell with another
|
||||
command
|
||||
- using `jobs -Z` to overwrite the shell process’ argument and
|
||||
- using jobs -Z to overwrite the shell process’ argument and
|
||||
environment space
|
||||
- using the `ARGV0` parameter to override `argv[0]` for external
|
||||
- using the ARGV0 parameter to override argv\[0\] for external
|
||||
commands
|
||||
- turning off restricted mode with `set +r` or `unsetopt RESTRICTED`
|
||||
- turning off restricted mode with set +r or unsetopt RESTRICTED
|
||||
|
||||
These restrictions are enforced after processing the startup files. The
|
||||
startup files should set up `PATH` to point to a directory of commands
|
||||
startup files should set up PATH to point to a directory of commands
|
||||
which can be safely invoked in the restricted environment. They may also
|
||||
add further restrictions by disabling selected builtins.
|
||||
|
||||
Restricted mode can also be activated any time by setting the
|
||||
`RESTRICTED` option. This immediately enables all the restrictions
|
||||
described above even if the shell still has not processed all startup
|
||||
files.
|
||||
Restricted mode can also be activated any time by setting the RESTRICTED
|
||||
option. This immediately enables all the restrictions described above
|
||||
even if the shell still has not processed all startup files.
|
||||
|
||||
A shell *Restricted Mode* is an outdated way to restrict what users may
|
||||
do: modern systems have better, safer and more reliable ways to confine
|
||||
@ -227,11 +226,11 @@ may be removed in a future version of zsh.
|
||||
It is important to realise that the restrictions only apply to the
|
||||
shell, not to the commands it runs (except for some shell builtins).
|
||||
While a restricted shell can only run the restricted list of commands
|
||||
accessible via the predefined ‘`PATH`’ variable, it does not prevent
|
||||
those commands from running any other command.
|
||||
accessible via the predefined ‘PATH’ variable, it does not prevent those
|
||||
commands from running any other command.
|
||||
|
||||
As an example, if ‘`env`’ is among the list of *allowed* commands, then
|
||||
it allows the user to run any command as ‘`env`’ is not a shell
|
||||
As an example, if ‘env’ is among the list of *allowed* commands, then it
|
||||
allows the user to run any command as ‘env’ is not a shell
|
||||
|
||||
So when implementing a restricted shell framework it is important to be
|
||||
fully aware of what actions each of the *allowed* commands or features
|
||||
@ -241,26 +240,26 @@ Many commands can have their behaviour affected by environment
|
||||
variables. Except for the few listed above, zsh does not restrict the
|
||||
setting of environment variables.
|
||||
|
||||
If a ‘`perl`’, ‘`python`’, ‘`bash`’, or other general purpose
|
||||
interpreted script it treated as a restricted command, the user can work
|
||||
around the restriction by setting specially crafted ‘`PERL5LIB`’,
|
||||
‘`PYTHONPATH`’, ‘`BASHENV`’ (etc.) environment variables. On GNU
|
||||
systems, any command can be made to run arbitrary code when performing
|
||||
character set conversion (including zsh itself) by setting a
|
||||
‘`GCONV_PATH`’ environment variable. Those are only a few examples.
|
||||
If a ‘perl’, ‘python’, ‘bash’, or other general purpose interpreted
|
||||
script it treated as a restricted command, the user can work around the
|
||||
restriction by setting specially crafted ‘PERL5LIB’, ‘PYTHONPATH’,
|
||||
‘BASHENV’ (etc.) environment variables. On GNU systems, any command can
|
||||
be made to run arbitrary code when performing character set conversion
|
||||
(including zsh itself) by setting a ‘GCONV_PATH’ environment variable.
|
||||
Those are only a few examples.
|
||||
|
||||
Bear in mind that, contrary to some other shells, ‘`readonly`’ is not a
|
||||
Bear in mind that, contrary to some other shells, ‘readonly’ is not a
|
||||
security feature in zsh as it can be undone and so cannot be used to
|
||||
mitigate the above.
|
||||
|
||||
A restricted shell only works if the allowed commands are few and
|
||||
carefully written so as not to grant more access to users than intended.
|
||||
It is also important to restrict what zsh module the user may load as
|
||||
some of them, such as ‘`zsh/system`’, ‘`zsh/mapfile`’ and ‘`zsh/files`’,
|
||||
allow bypassing most of the restrictions.
|
||||
some of them, such as ‘zsh/system’, ‘zsh/mapfile’ and ‘zsh/files’, allow
|
||||
bypassing most of the restrictions.
|
||||
|
||||
-----
|
||||
------------------------------------------------------------------------
|
||||
|
||||
This document was generated on *February 15, 2020* using
|
||||
[*texi2html 5.0*](http://www.nongnu.org/texi2html/).
|
||||
Zsh version 5.8, released on February 14, 2020.
|
||||
This document was generated on *May 14, 2022* using [*texi2html
|
||||
5.0*](http://www.nongnu.org/texi2html/).
|
||||
Zsh version 5.9, released on May 14, 2022.
|
||||
|
||||
@ -8,28 +8,28 @@
|
||||
|
||||
<!-- END doctoc generated TOC please keep comment here to allow auto update -->
|
||||
|
||||
<span id="Jobs-_0026-Signals"></span>
|
||||
<span id="Jobs-_0026-Signals-1"></span>
|
||||
<span id="Jobs-_0026-Signals"></span> <span
|
||||
id="Jobs-_0026-Signals-1"></span>
|
||||
|
||||
# 10 Jobs & Signals
|
||||
|
||||
-----
|
||||
------------------------------------------------------------------------
|
||||
|
||||
<span id="Jobs"></span>
|
||||
|
||||
## 10.1 Jobs
|
||||
|
||||
<span id="index-jobs"></span>
|
||||
<span id="index-MONITOR_002c-use-of"></span>
|
||||
<span id="index-jobs"></span> <span
|
||||
id="index-MONITOR_002c-use-of"></span>
|
||||
|
||||
If the `MONITOR` option is set, an interactive shell associates a *job*
|
||||
If the MONITOR option is set, an interactive shell associates a *job*
|
||||
with each pipeline. command, and assigns them small integer numbers.
|
||||
When a job is started asynchronously with ‘`&`’, the shell prints a line
|
||||
When a job is started asynchronously with ‘&’, the shell prints a line
|
||||
to standard error which looks like:
|
||||
|
||||
<div class="example">
|
||||
|
||||
``` example
|
||||
```zsh
|
||||
[1] 1234
|
||||
```
|
||||
|
||||
@ -38,22 +38,22 @@ to standard error which looks like:
|
||||
indicating that the job which was started asynchronously was job number
|
||||
1 and had one (top-level) process, whose process ID was 1234.
|
||||
|
||||
If a job is started with ‘`&|`’ or ‘`&!`’, then that job is immediately
|
||||
If a job is started with ‘&\|’ or ‘&!’, then that job is immediately
|
||||
disowned. After startup, it to the job control features described here.
|
||||
|
||||
If you are running a job and wish to do something else you may hit the
|
||||
key ^Z (control-Z) which sends a `TSTP` signal to the current job: this
|
||||
key may be redefined by the `susp` option of the external `stty`
|
||||
command. <span id="index-jobs_002c-suspending"></span>
|
||||
<span id="index-suspending-jobs"></span> The shell will then normally
|
||||
indicate that the job has been ‘suspended’, and print another prompt.
|
||||
You can then manipulate the state of this job,
|
||||
<span id="index-bg_002c-use-of"></span> putting it in the background
|
||||
with the `bg` command, or run some other commands and then eventually
|
||||
bring the job back into the foreground with
|
||||
<span id="index-fg_002c-use-of"></span> the foreground command `fg`. A
|
||||
^Z takes effect immediately and is like an interrupt in that pending
|
||||
output and unread input are discarded when it is typed.
|
||||
key ^Z (control-Z) which sends a TSTP signal to the current job: this
|
||||
key may be redefined by the susp option of the external stty command.
|
||||
<span id="index-jobs_002c-suspending"></span> <span
|
||||
id="index-suspending-jobs"></span> The shell will then normally indicate
|
||||
that the job has been ‘suspended’, and print another prompt. You can
|
||||
then manipulate the state of this job, <span
|
||||
id="index-bg_002c-use-of"></span> putting it in the background with the
|
||||
bg command, or run some other commands and then eventually bring the job
|
||||
back into the foreground with <span id="index-fg_002c-use-of"></span>
|
||||
the foreground command fg. A ^Z takes effect immediately and is like an
|
||||
interrupt in that pending output and unread input are discarded when it
|
||||
is typed.
|
||||
|
||||
A job being run in the background will suspend if it tries to read from
|
||||
the terminal.
|
||||
@ -62,109 +62,109 @@ Note that if the job running in the foreground is a shell function, then
|
||||
suspending it will have the effect of causing the shell to fork. This is
|
||||
necessary to separate the function’s state from that of the parent shell
|
||||
performing the job control, so that the latter can return to the command
|
||||
line prompt. As a result, even if `fg` is used to continue the job the
|
||||
line prompt. As a result, even if fg is used to continue the job the
|
||||
function will no longer be part of the parent shell, and any variables
|
||||
set by the function will not be visible in the parent shell. Thus the
|
||||
behaviour is different from the case where the function was never
|
||||
suspended. Zsh is different from many other shells in this regard.
|
||||
|
||||
One additional side effect is that use of `disown` with a job created by
|
||||
One additional side effect is that use of disown with a job created by
|
||||
suspending shell code in this fashion is delayed: the job can only be
|
||||
disowned once any process started from the parent shell has terminated.
|
||||
At that point, the disowned job disappears silently from the job list.
|
||||
|
||||
The same behaviour is found when the shell is executing code as the
|
||||
right hand side of a pipeline or any complex shell construct such as
|
||||
`if`, `for`, etc., in order that the entire block of code can be managed
|
||||
as a single job. <span id="index-background-jobs_002c-I_002fO"></span>
|
||||
<span id="index-jobs_002c-background_002c-I_002fO"></span> Background
|
||||
jobs are normally allowed to produce output, but this can be disabled by
|
||||
giving the command ‘`stty tostop`’. If you set this tty option, then
|
||||
background jobs will suspend when they try to produce output like they
|
||||
do when they try to read input.
|
||||
right hand side of a pipeline or any complex shell construct such as if,
|
||||
for, etc., in order that the entire block of code can be managed as a
|
||||
single job. <span id="index-background-jobs_002c-I_002fO"></span> <span
|
||||
id="index-jobs_002c-background_002c-I_002fO"></span> Background jobs are
|
||||
normally allowed to produce output, but this can be disabled by giving
|
||||
the command ‘stty tostop’. If you set this tty option, then background
|
||||
jobs will suspend when they try to produce output like they do when they
|
||||
try to read input.
|
||||
|
||||
When a command is suspended and continued later with the `fg` or `wait`
|
||||
When a command is suspended and continued later with the fg or wait
|
||||
builtins, zsh restores tty modes that were in effect when it was
|
||||
suspended. This (intentionally) does not apply if the command is
|
||||
continued via ‘`kill -CONT`’, nor when it is continued with `bg`.
|
||||
continued via ‘kill -CONT’, nor when it is continued with bg.
|
||||
|
||||
<span id="index-jobs_002c-referring-to"></span>
|
||||
<span id="index-referring-to-jobs"></span>
|
||||
<span id="index-jobs_002c-referring-to"></span> <span
|
||||
id="index-referring-to-jobs"></span>
|
||||
|
||||
There are several ways to refer to jobs in the shell. A job can be
|
||||
referred to by the process ID of any process of the job or by one of the
|
||||
following:
|
||||
|
||||
- `%``number`
|
||||
The job with the given number.
|
||||
%`number`
|
||||
The job with the given number.
|
||||
|
||||
- `%``string`
|
||||
The last job whose command line begins with `string`.
|
||||
%`string`
|
||||
The last job whose command line begins with `string`.
|
||||
|
||||
- `%?``string`
|
||||
The last job whose command line contains `string`.
|
||||
%?`string`
|
||||
The last job whose command line contains `string`.
|
||||
|
||||
- `%%`
|
||||
Current job.
|
||||
%%
|
||||
Current job.
|
||||
|
||||
- `%+`
|
||||
Equivalent to ‘`%%`’.
|
||||
%+
|
||||
Equivalent to ‘%%’.
|
||||
|
||||
- `%-`
|
||||
Previous job.
|
||||
%-
|
||||
Previous job.
|
||||
|
||||
The shell learns immediately whenever a process changes state.
|
||||
<span id="index-NOTIFY_002c-use-of"></span> It normally informs you
|
||||
whenever a job becomes blocked so that no further progress is possible.
|
||||
If the `NOTIFY` option is not set, it waits until just before it prints
|
||||
a prompt before it informs you. All such notifications are sent directly
|
||||
to the terminal, not to the standard output or standard error.
|
||||
The shell learns immediately whenever a process changes state. <span
|
||||
id="index-NOTIFY_002c-use-of"></span> It normally informs you whenever a
|
||||
job becomes blocked so that no further progress is possible. If the
|
||||
NOTIFY option is not set, it waits until just before it prints a prompt
|
||||
before it informs you. All such notifications are sent directly to the
|
||||
terminal, not to the standard output or standard error.
|
||||
|
||||
When the monitor mode is on, each background job that completes triggers
|
||||
any trap set for `CHLD`.
|
||||
any trap set for CHLD.
|
||||
|
||||
When you try to leave the shell while jobs are running or suspended, you
|
||||
will be warned that ‘You have suspended (running) jobs’. You may use the
|
||||
`jobs` command to see what they are. If you do this or immediately try
|
||||
to exit again, the shell will not warn you a second time; the suspended
|
||||
jobs will be terminated, and the running jobs will be sent a `SIGHUP`
|
||||
signal, if the `HUP` option is set.
|
||||
<span id="index-HUP_002c-use-of"></span>
|
||||
jobs command to see what they are. If you do this or immediately try to
|
||||
exit again, the shell will not warn you a second time; the suspended
|
||||
jobs will be terminated, and the running jobs will be sent a SIGHUP
|
||||
signal, if the HUP option is set. <span
|
||||
id="index-HUP_002c-use-of"></span>
|
||||
|
||||
<span id="index-jobs_002c-disowning"></span>
|
||||
<span id="index-disowning-jobs"></span>
|
||||
<span id="index-disown_002c-use-of"></span>
|
||||
<span id="index-jobs_002c-disowning"></span> <span
|
||||
id="index-disowning-jobs"></span> <span
|
||||
id="index-disown_002c-use-of"></span>
|
||||
|
||||
To avoid having the shell terminate the running jobs, either use the
|
||||
nohup command (see man page nohup(1)) or the `disown` builtin.
|
||||
nohup(1) command or the disown builtin.
|
||||
|
||||
-----
|
||||
------------------------------------------------------------------------
|
||||
|
||||
<span id="Signals"></span>
|
||||
|
||||
## 10.2 Signals
|
||||
|
||||
The `INT` and `QUIT` signals for an invoked command are ignored if the
|
||||
command is followed by ‘`&`’ and the `MONITOR` option is not active. The
|
||||
shell itself always ignores the `QUIT` signal. Otherwise, signals have
|
||||
the values inherited by the shell from its parent (but see the
|
||||
`TRAP``NAL` special functions in [Functions](Functions.html#Functions)).
|
||||
The INT and QUIT signals for an invoked command are ignored if the
|
||||
command is followed by ‘&’ and the MONITOR option is not active. The
|
||||
shell itself always ignores the QUIT signal. Otherwise, signals have the
|
||||
values inherited by the shell from its parent (but see the TRAP`NAL`
|
||||
special functions in [Functions](Functions.html#Functions)).
|
||||
|
||||
<span id="index-exiting-shell_002c-and-asynchronous-jobs"></span>
|
||||
<span id="index-asynchronous-jobs_002c-and-exiting-shell"></span>
|
||||
<span id="index-jobs_002c-asynchronous_002c-and-exiting-shell"></span>
|
||||
<span id="index-exiting-shell_002c-and-asynchronous-jobs"></span> <span
|
||||
id="index-asynchronous-jobs_002c-and-exiting-shell"></span> <span
|
||||
id="index-jobs_002c-asynchronous_002c-and-exiting-shell"></span>
|
||||
|
||||
Certain jobs are run asynchronously by the shell other than those
|
||||
explicitly put into the background; even in cases where the shell would
|
||||
usually wait for such jobs, an explicit `exit` command or exit due to
|
||||
the option `ERR_EXIT` will cause the shell to exit without waiting.
|
||||
Examples of such asynchronous jobs are process substitution, see
|
||||
[Process Substitution](Expansion.html#Process-Substitution), and the
|
||||
handler processes for multios, see the section Multios in
|
||||
usually wait for such jobs, an explicit exit command or exit due to the
|
||||
option ERR_EXIT will cause the shell to exit without waiting. Examples
|
||||
of such asynchronous jobs are process substitution, see [Process
|
||||
Substitution](Expansion.html#Process-Substitution), and the handler
|
||||
processes for multios, see the section *Multios* in
|
||||
[Redirection](Redirection.html#Redirection).
|
||||
|
||||
-----
|
||||
------------------------------------------------------------------------
|
||||
|
||||
This document was generated on *February 15, 2020* using
|
||||
[*texi2html 5.0*](http://www.nongnu.org/texi2html/).
|
||||
Zsh version 5.8, released on February 14, 2020.
|
||||
This document was generated on *May 14, 2022* using [*texi2html
|
||||
5.0*](http://www.nongnu.org/texi2html/).
|
||||
Zsh version 5.9, released on May 14, 2022.
|
||||
|
||||
File diff suppressed because it is too large
Load Diff
File diff suppressed because it is too large
Load Diff
@ -11,459 +11,442 @@
|
||||
- [13.2.4 Date and time](#1324-date-and-time)
|
||||
- [13.2.5 Visual effects](#1325-visual-effects)
|
||||
- [13.3 Conditional Substrings in Prompts](#133-conditional-substrings-in-prompts)
|
||||
- [](#)
|
||||
|
||||
<!-- END doctoc generated TOC please keep comment here to allow auto update -->
|
||||
|
||||
<span id="Prompt-Expansion"></span>
|
||||
<span id="Prompt-Expansion-1"></span>
|
||||
<span id="Prompt-Expansion"></span> <span
|
||||
id="Prompt-Expansion-1"></span>
|
||||
|
||||
# 13 Prompt Expansion
|
||||
|
||||
-----
|
||||
------------------------------------------------------------------------
|
||||
|
||||
<span id="Expansion-of-Prompt-Sequences"></span>
|
||||
|
||||
## 13.1 Expansion of Prompt Sequences
|
||||
|
||||
<span id="index-prompt-expansion"></span>
|
||||
<span id="index-expansion_002c-prompt"></span>
|
||||
<span id="index-prompt-expansion"></span> <span
|
||||
id="index-expansion_002c-prompt"></span>
|
||||
|
||||
Prompt sequences undergo a special form of expansion. This type of
|
||||
expansion is also available using the `-P` option to the `print`
|
||||
builtin.
|
||||
expansion is also available using the -P option to the print builtin.
|
||||
|
||||
<span id="index-PROMPT_005fSUBST_002c-use-of"></span>
|
||||
|
||||
If the `PROMPT_SUBST` option is set, the prompt string is first
|
||||
subjected to *parameter expansion*, *command substitution* and
|
||||
*arithmetic expansion*. See [Expansion](Expansion.html#Expansion).
|
||||
If the PROMPT_SUBST option is set, the prompt string is first subjected
|
||||
to *parameter expansion*, *command substitution* and *arithmetic
|
||||
expansion*. See [Expansion](Expansion.html#Expansion).
|
||||
|
||||
Certain escape sequences may be recognised in the prompt string.
|
||||
|
||||
<span id="index-PROMPT_005fBANG_002c-use-of"></span>
|
||||
|
||||
If the `PROMPT_BANG` option is set, a ‘`!`’ in the prompt is replaced by
|
||||
the current history event number. A literal ‘`!`’ may then be
|
||||
represented as ‘`!!`’.
|
||||
If the PROMPT_BANG option is set, a ‘!’ in the prompt is replaced by the
|
||||
current history event number. A literal ‘!’ may then be represented as
|
||||
‘!!’.
|
||||
|
||||
<span id="index-PROMPT_005fPERCENT_002c-use-of"></span>
|
||||
|
||||
If the `PROMPT_PERCENT` option is set, certain escape sequences that
|
||||
start with ‘`%`’ are expanded. Many escapes are followed by a single
|
||||
character, although some of these take an optional integer argument that
|
||||
should appear between the ‘`%`’ and the next character of the sequence.
|
||||
More complicated escape sequences are available to provide conditional
|
||||
If the PROMPT_PERCENT option is set, certain escape sequences that start
|
||||
with ‘%’ are expanded. Many escapes are followed by a single character,
|
||||
although some of these take an optional integer argument that should
|
||||
appear between the ‘%’ and the next character of the sequence. More
|
||||
complicated escape sequences are available to provide conditional
|
||||
expansion.
|
||||
|
||||
-----
|
||||
------------------------------------------------------------------------
|
||||
|
||||
<span id="Simple-Prompt-Escapes"></span>
|
||||
|
||||
## 13.2 Simple Prompt Escapes
|
||||
|
||||
-----
|
||||
------------------------------------------------------------------------
|
||||
|
||||
<span id="Special-characters"></span>
|
||||
|
||||
### 13.2.1 Special characters
|
||||
|
||||
- `%%`
|
||||
A ‘`%`’.
|
||||
%%
|
||||
A ‘%’.
|
||||
|
||||
- `%)`
|
||||
A ‘`)`’.
|
||||
%)
|
||||
A ‘)’.
|
||||
|
||||
-----
|
||||
------------------------------------------------------------------------
|
||||
|
||||
<span id="Login-information"></span>
|
||||
|
||||
### 13.2.2 Login information
|
||||
|
||||
- `%l`
|
||||
The line (tty) the user is logged in on, without ‘`/dev/`’ prefix.
|
||||
If the name starts with ‘`/dev/tty`’, that prefix is stripped.
|
||||
%l
|
||||
The line (tty) the user is logged in on, without ‘/dev/’ prefix. If the
|
||||
name starts with ‘/dev/tty’, that prefix is stripped.
|
||||
|
||||
- `%M`
|
||||
The full machine hostname.
|
||||
%M
|
||||
The full machine hostname.
|
||||
|
||||
- `%m`
|
||||
The hostname up to the first ‘`.`’. An integer may follow the ‘`%`’
|
||||
to specify how many components of the hostname are desired. With a
|
||||
negative integer, trailing components of the hostname are shown.
|
||||
%m
|
||||
The hostname up to the first ‘.’. An integer may follow the ‘%’ to
|
||||
specify how many components of the hostname are desired. With a negative
|
||||
integer, trailing components of the hostname are shown.
|
||||
|
||||
- `%n`
|
||||
`$USERNAME`.
|
||||
%n
|
||||
$USERNAME.
|
||||
|
||||
- `%y`
|
||||
The line (tty) the user is logged in on, without ‘`/dev/`’ prefix.
|
||||
This does not treat ‘`/dev/tty`’ names specially.
|
||||
%y
|
||||
The line (tty) the user is logged in on, without ‘/dev/’ prefix. This
|
||||
does not treat ‘/dev/tty’ names specially.
|
||||
|
||||
-----
|
||||
------------------------------------------------------------------------
|
||||
|
||||
<span id="Shell-state"></span>
|
||||
|
||||
### 13.2.3 Shell state
|
||||
|
||||
- `%#`
|
||||
A ‘`#`’ if the shell is running with privileges, a ‘`%`’ if not.
|
||||
Equivalent to ‘`%(!.#.%%)`’. The definition of ‘privileged’, for
|
||||
these purposes, is that either the effective user ID is zero, or, if
|
||||
POSIX.1e capabilities are supported, that capability vectors.
|
||||
%#
|
||||
A ‘#’ if the shell is running with privileges, a ‘%’ if not. Equivalent
|
||||
to ‘%(!.#.%%)’. The definition of ‘privileged’, for these purposes, is
|
||||
that either the effective user ID is zero, or, if POSIX.1e capabilities
|
||||
are supported, that capability vectors.
|
||||
|
||||
- `%?`
|
||||
The return status of the last command executed just before the
|
||||
prompt.
|
||||
%?
|
||||
The return status of the last command executed just before the prompt.
|
||||
|
||||
- `%_`
|
||||
The status of the parser, i.e. the shell constructs (like ‘`if`’ and
|
||||
‘`for`’) that have been started on the command line. If given an
|
||||
integer number that many strings will be printed; zero or negative
|
||||
or no integer means print as many as there are. This is most useful
|
||||
in prompts `PS2` for continuation lines and `PS4` for debugging with
|
||||
the `XTRACE` option; in the latter case it will also work
|
||||
non-interactively.
|
||||
%\_
|
||||
The status of the parser, i.e. the shell constructs (like ‘if’ and
|
||||
‘for’) that have been started on the command line. If given an integer
|
||||
number that many strings will be printed; zero or negative or no integer
|
||||
means print as many as there are. This is most useful in prompts PS2 for
|
||||
continuation lines and PS4 for debugging with the XTRACE option; in the
|
||||
latter case it will also work non-interactively.
|
||||
|
||||
- `%^`
|
||||
The status of the parser in reverse. This is the same as ‘`%_`’
|
||||
other than the order of strings. It is often used in `RPS2`.
|
||||
%^
|
||||
The status of the parser in reverse. This is the same as ‘%\_’ other
|
||||
than the order of strings. It is often used in RPS2.
|
||||
|
||||
- `%d`
|
||||
`%/`
|
||||
Current working directory. If an integer follows the ‘`%`’, it
|
||||
specifies a number of trailing components of the current working
|
||||
directory to show; zero means the whole path. A negative integer
|
||||
specifies leading components, i.e. `%-1d` specifies the first
|
||||
component.
|
||||
%d
|
||||
%/
|
||||
Current working directory. If an integer follows the ‘%’, it specifies a
|
||||
number of trailing components of the current working directory to show;
|
||||
zero means the whole path. A negative integer specifies leading
|
||||
components, i.e. %-1d specifies the first component.
|
||||
|
||||
- `%~`
|
||||
As `%d` and `%/`, but if the current working directory starts with
|
||||
`$HOME`, that part is replaced by a ‘`~`’. Furthermore, if it has a
|
||||
named directory as its prefix, that part is replaced by a ‘`~`’
|
||||
followed by the name of the directory, but only if the result is
|
||||
shorter than the full path; [Filename
|
||||
Expansion](Expansion.html#Filename-Expansion).
|
||||
%\~
|
||||
As %d and %/, but if the current working directory starts with $HOME,
|
||||
that part is replaced by a ‘\~’. Furthermore, if it has a named
|
||||
directory as its prefix, that part is replaced by a ‘\~’ followed by the
|
||||
name of the directory, but only if the result is shorter than the full
|
||||
path; [Filename Expansion](Expansion.html#Filename-Expansion).
|
||||
|
||||
- `%e`
|
||||
Evaluation depth of the current sourced file, shell function, or
|
||||
`eval`. This is incremented or decremented every time the value of
|
||||
`%N` is set or reverted to a previous value, respectively. This is
|
||||
most useful for debugging as part of `$PS4`.
|
||||
%e
|
||||
Evaluation depth of the current sourced file, shell function, or eval.
|
||||
This is incremented or decremented every time the value of %N is set or
|
||||
reverted to a previous value, respectively. This is most useful for
|
||||
debugging as part of $PS4.
|
||||
|
||||
- `%h`
|
||||
`%!`
|
||||
Current history event number.
|
||||
%h
|
||||
%!
|
||||
Current history event number.
|
||||
|
||||
- `%i`
|
||||
The line number currently being executed in the script, sourced
|
||||
file, or shell function given by `%N`. This is most useful for
|
||||
debugging as part of `$PS4`.
|
||||
%i
|
||||
The line number currently being executed in the script, sourced file, or
|
||||
shell function given by %N. This is most useful for debugging as part of
|
||||
$PS4.
|
||||
|
||||
- `%I`
|
||||
The line number currently being executed in the file `%x`. This is
|
||||
similar to `%i`, but the line number is always a line number in the
|
||||
file where the code was defined, even if the code is a shell
|
||||
function.
|
||||
%I
|
||||
The line number currently being executed in the file %x. This is similar
|
||||
to %i, but the line number is always a line number in the file where the
|
||||
code was defined, even if the code is a shell function.
|
||||
|
||||
- `%j`
|
||||
The number of jobs.
|
||||
%j
|
||||
The number of jobs.
|
||||
|
||||
- `%L`
|
||||
The current value of `$SHLVL`.
|
||||
%L
|
||||
The current value of $SHLVL.
|
||||
|
||||
- `%N`
|
||||
The name of the script, sourced file, or shell function that zsh is
|
||||
currently executing, whichever was started most recently. If there
|
||||
is none, this is equivalent to the parameter `$0`. An integer may
|
||||
follow the ‘`%`’ to specify a number of trailing path components to
|
||||
show; zero means the full path. A negative integer specifies leading
|
||||
components.
|
||||
%N
|
||||
The name of the script, sourced file, or shell function that zsh is
|
||||
currently executing, whichever was started most recently. If there is
|
||||
none, this is equivalent to the parameter $0. An integer may follow the
|
||||
‘%’ to specify a number of trailing path components to show; zero means
|
||||
the full path. A negative integer specifies leading components.
|
||||
|
||||
- `%x`
|
||||
The name of the file containing the source code currently being
|
||||
executed. This behaves as `%N` except that function and eval command
|
||||
names are not shown, instead the file where they were defined.
|
||||
%x
|
||||
The name of the file containing the source code currently being
|
||||
executed. This behaves as %N except that function and eval command names
|
||||
are not shown, instead the file where they were defined.
|
||||
|
||||
- `%c`
|
||||
`%.`
|
||||
`%C`
|
||||
Trailing component of the current working directory. An integer may
|
||||
follow the ‘`%`’ to get more than one component. Unless ‘`%C`’ is
|
||||
used, tilde contraction is performed first. These are deprecated as
|
||||
`%c` and `%C` are equivalent to `%1~` and `%1/`, respectively, while
|
||||
explicit positive integers have the same effect as for the latter
|
||||
two sequences.
|
||||
%c
|
||||
%.
|
||||
%C
|
||||
Trailing component of the current working directory. An integer may
|
||||
follow the ‘%’ to get more than one component. Unless ‘%C’ is used,
|
||||
tilde contraction is performed first. These are deprecated as %c and %C
|
||||
are equivalent to %1\~ and %1/, respectively, while explicit positive
|
||||
integers have the same effect as for the latter two sequences.
|
||||
|
||||
-----
|
||||
------------------------------------------------------------------------
|
||||
|
||||
<span id="Date-and-time"></span>
|
||||
|
||||
### 13.2.4 Date and time
|
||||
|
||||
- `%D`
|
||||
The date in `yy``-``mm``-``dd` format.
|
||||
%D
|
||||
The date in `yy`-`mm`-`dd` format.
|
||||
|
||||
- `%T`
|
||||
Current time of day, in 24-hour format.
|
||||
%T
|
||||
Current time of day, in 24-hour format.
|
||||
|
||||
- `%t`
|
||||
`%@`
|
||||
Current time of day, in 12-hour, am/pm format.
|
||||
%t
|
||||
%@
|
||||
Current time of day, in 12-hour, am/pm format.
|
||||
|
||||
- `%*`
|
||||
Current time of day in 24-hour format, with seconds.
|
||||
%\*
|
||||
Current time of day in 24-hour format, with seconds.
|
||||
|
||||
- `%w`
|
||||
The date in `day``-``dd` format.
|
||||
%w
|
||||
The date in `day`-`dd` format.
|
||||
|
||||
- `%W`
|
||||
The date in `mm``/``dd``/``yy` format.
|
||||
%W
|
||||
The date in `mm`/`dd`/`yy` format.
|
||||
|
||||
- `%D{``string``}`
|
||||
`string` is formatted using the `strftime` function. See man page
|
||||
strftime(3) for more details. Various zsh extensions provide numbers
|
||||
with no leading zero or space if the number is a single digit:
|
||||
%D{`string`}
|
||||
`string` is formatted using the strftime function. See strftime(3) for
|
||||
more details. Various zsh extensions provide numbers with no leading
|
||||
zero or space if the number is a single digit:
|
||||
|
||||
- `%f`
|
||||
a day of the month
|
||||
%f
|
||||
a day of the month
|
||||
|
||||
- `%K`
|
||||
the hour of the day on the 24-hour clock
|
||||
%K
|
||||
the hour of the day on the 24-hour clock
|
||||
|
||||
- `%L`
|
||||
the hour of the day on the 12-hour clock
|
||||
%L
|
||||
the hour of the day on the 12-hour clock
|
||||
|
||||
In addition, if the system supports the POSIX `gettimeofday` system
|
||||
call, `%.` provides decimal fractions of a second since the epoch
|
||||
with leading zeroes. By default three decimal places are provided,
|
||||
but a number of digits up to 9 may be given following the `%`; hence
|
||||
`%6.` outputs microseconds, and `%9.` outputs nanoseconds. (The
|
||||
latter requires a nanosecond-precision `clock_gettime`; systems
|
||||
lacking this will return a value multiplied by the appropriate power
|
||||
of 10.) A typical example of this is the format ‘`%D{%H:%M:%S.%.}`’.
|
||||
In addition, if the system supports the POSIX gettimeofday system call,
|
||||
%. provides decimal fractions of a second since the epoch with leading
|
||||
zeroes. By default three decimal places are provided, but a number of
|
||||
digits up to 9 may be given following the %; hence %6. outputs
|
||||
microseconds, and %9. outputs nanoseconds. (The latter requires a
|
||||
nanosecond-precision clock_gettime; systems lacking this will return a
|
||||
value multiplied by the appropriate power of 10.) A typical example of
|
||||
this is the format ‘%D{%H:%M:%S.%.}’.
|
||||
|
||||
The GNU extension `%N` is handled as a synonym for `%9.`.
|
||||
The GNU extension %N is handled as a synonym for %9..
|
||||
|
||||
Additionally, the GNU extension that a ‘`-`’ between the `%` and the
|
||||
format character causes a leading zero or space to be stripped is
|
||||
handled directly by the shell for the format characters `d`, `f`,
|
||||
`H`, `k`, `l`, `m`, `M`, `S` and `y`; any other format characters
|
||||
are provided to the system’s strftime(3) with any leading ‘`-`’
|
||||
present, so the handling is system dependent. Further GNU (or other)
|
||||
extensions are also passed to strftime(3) and may work if the system
|
||||
supports them.
|
||||
Additionally, the GNU extension that a ‘-’ between the % and the format
|
||||
character causes a leading zero or space to be stripped is handled
|
||||
directly by the shell for the format characters d, f, H, k, l, m, M, S
|
||||
and y; any other format characters are provided to the system’s
|
||||
strftime(3) with any leading ‘-’ present, so the handling is system
|
||||
dependent. Further GNU (or other) extensions are also passed to
|
||||
strftime(3) and may work if the system supports them.
|
||||
|
||||
-----
|
||||
------------------------------------------------------------------------
|
||||
|
||||
<span id="Visual-effects"></span>
|
||||
|
||||
### 13.2.5 Visual effects
|
||||
|
||||
- `%B` (`%b`)
|
||||
Start (stop) boldface mode.
|
||||
%B (%b)
|
||||
Start (stop) boldface mode.
|
||||
|
||||
- `%E`
|
||||
Clear to end of line.
|
||||
%E
|
||||
Clear to end of line.
|
||||
|
||||
- `%U` (`%u`)
|
||||
Start (stop) underline mode.
|
||||
%U (%u)
|
||||
Start (stop) underline mode.
|
||||
|
||||
- `%S` (`%s`)
|
||||
Start (stop) standout mode.
|
||||
%S (%s)
|
||||
Start (stop) standout mode.
|
||||
|
||||
- `%F` (`%f`)
|
||||
Start (stop) using a different foreground colour, if supported by
|
||||
the terminal. The colour may be specified two ways: either as a
|
||||
numeric argument, as normal, or by a sequence in braces following
|
||||
the `%F`, for example `%F{red}`. In the latter case the values
|
||||
allowed are as described for the `fg` `zle_highlight` attribute;
|
||||
[Character
|
||||
Highlighting](Zsh-Line-Editor.html#Character-Highlighting). This
|
||||
means that numeric colours are allowed in the second format also.
|
||||
%F (%f)
|
||||
Start (stop) using a different foreground colour, if supported by the
|
||||
terminal. The colour may be specified two ways: either as a numeric
|
||||
argument, as normal, or by a sequence in braces following the %F, for
|
||||
example %F{red}. In the latter case the values allowed are as described
|
||||
for the fg zle_highlight attribute; [Character
|
||||
Highlighting](Zsh-Line-Editor.html#Character-Highlighting). This means
|
||||
that numeric colours are allowed in the second format also.
|
||||
|
||||
- `%K` (`%k`)
|
||||
Start (stop) using a different bacKground colour. The syntax is
|
||||
identical to that for `%F` and `%f`.
|
||||
%K (%k)
|
||||
Start (stop) using a different bacKground colour. The syntax is
|
||||
identical to that for %F and %f.
|
||||
|
||||
- `%{`...`%}`
|
||||
Include a string as a literal escape sequence. The string within the
|
||||
braces should not change the cursor position. Brace pairs can nest.
|
||||
%{...%}
|
||||
Include a string as a literal escape sequence. The string within the
|
||||
braces should not change the cursor position. Brace pairs can nest.
|
||||
|
||||
A positive numeric argument between the `%` and the `{` is treated
|
||||
as described for `%G` below.
|
||||
A positive numeric argument between the % and the { is treated as
|
||||
described for %G below.
|
||||
|
||||
- `%G`
|
||||
Within a `%{`...`%}` sequence, include a ‘glitch’: that is, assume
|
||||
that a single character width will be output. This is useful when
|
||||
outputting characters that otherwise cannot be correctly handled by
|
||||
the shell, such as the alternate character set on some terminals.
|
||||
The characters in question can be included within a `%{`...`%}`
|
||||
sequence together with the appropriate number of `%G` sequences to
|
||||
indicate the correct width. An integer between the ‘`%`’ and ‘`G`’
|
||||
indicates a character width other than one. Hence `%{``seq``%2G%}`
|
||||
outputs `seq` and assumes it takes up the width of two standard
|
||||
characters.
|
||||
%G
|
||||
Within a %{...%} sequence, include a ‘glitch’: that is, assume that a
|
||||
single character width will be output. This is useful when outputting
|
||||
characters that otherwise cannot be correctly handled by the shell, such
|
||||
as the alternate character set on some terminals. The characters in
|
||||
question can be included within a %{...%} sequence together with the
|
||||
appropriate number of %G sequences to indicate the correct width. An
|
||||
integer between the ‘%’ and ‘G’ indicates a character width other than
|
||||
one. Hence %{`seq`%2G%} outputs `seq` and assumes it takes up the width
|
||||
of two standard characters.
|
||||
|
||||
Multiple uses of `%G` accumulate in the obvious fashion; the
|
||||
position of the `%G` is unimportant. Negative integers are not
|
||||
handled.
|
||||
Multiple uses of %G accumulate in the obvious fashion; the position of
|
||||
the %G is unimportant. Negative integers are not handled.
|
||||
|
||||
Note that when prompt truncation is in use it is advisable to divide
|
||||
up output into single characters within each `%{`...`%}` group so
|
||||
that the correct truncation point can be found.
|
||||
Note that when prompt truncation is in use it is advisable to divide up
|
||||
output into single characters within each %{...%} group so that the
|
||||
correct truncation point can be found.
|
||||
|
||||
-----
|
||||
------------------------------------------------------------------------
|
||||
|
||||
<span id="Conditional-Substrings-in-Prompts"></span>
|
||||
|
||||
## 13.3 Conditional Substrings in Prompts
|
||||
|
||||
- `%v`
|
||||
<span id="index-psvar_002c-use-of"></span>
|
||||
%v
|
||||
<span id="index-psvar_002c-use-of"></span>
|
||||
|
||||
The value of the first element of the `psvar` array parameter.
|
||||
Following the ‘`%`’ with an integer gives that element of the array.
|
||||
Negative integers count from the end of the array.
|
||||
The value of the first element of the psvar array parameter. Following
|
||||
the ‘%’ with an integer gives that element of the array. Negative
|
||||
integers count from the end of the array.
|
||||
|
||||
- `%(``x``.``true-text``.``false-text``)`
|
||||
Specifies a ternary expression. The character following the `x` is
|
||||
arbitrary; the same character is used to separate the text for the
|
||||
‘true’ result from that for the ‘false’ result. This separator may
|
||||
not appear in the `true-text`, except as part of a %-escape
|
||||
sequence. A ‘`)`’ may appear in the `false-text` as ‘`%)`’.
|
||||
`true-text` and `false-text` may both contain arbitrarily-nested
|
||||
escape sequences, including further ternary expressions.
|
||||
%(`x`.`true-text`.`false-text`)
|
||||
Specifies a ternary expression. The character following the `x` is
|
||||
arbitrary; the same character is used to separate the text for the
|
||||
‘true’ result from that for the ‘false’ result. This separator may not
|
||||
appear in the `true-text`, except as part of a %-escape sequence. A ‘)’
|
||||
may appear in the `false-text` as ‘%)’. `true-text` and `false-text` may
|
||||
both contain arbitrarily-nested escape sequences, including further
|
||||
ternary expressions.
|
||||
|
||||
The left parenthesis may be preceded or followed by a positive
|
||||
integer `n`, which defaults to zero. A negative integer will be
|
||||
multiplied by -1, except as noted below for ‘`l`’. The test
|
||||
character `x` may be any of the following:
|
||||
The left parenthesis may be preceded or followed by a positive integer
|
||||
`n`, which defaults to zero. A negative integer will be multiplied by
|
||||
-1, except as noted below for ‘l’. The test character `x` may be any of
|
||||
the following:
|
||||
|
||||
- `!`
|
||||
True if the shell is running with privileges.
|
||||
!
|
||||
True if the shell is running with privileges.
|
||||
|
||||
- `#`
|
||||
True if the effective uid of the current process is `n`.
|
||||
#
|
||||
True if the effective uid of the current process is `n`.
|
||||
|
||||
- `?`
|
||||
True if the exit status of the last command was `n`.
|
||||
?
|
||||
True if the exit status of the last command was `n`.
|
||||
|
||||
- `_`
|
||||
True if at least `n` shell constructs were started.
|
||||
\_
|
||||
True if at least `n` shell constructs were started.
|
||||
|
||||
- `C`
|
||||
`/`
|
||||
True if the current absolute path has at least `n` elements
|
||||
relative to the root directory, hence `/` is counted as 0
|
||||
elements.
|
||||
C
|
||||
/
|
||||
True if the current absolute path has at least `n` elements relative to
|
||||
the root directory, hence / is counted as 0 elements.
|
||||
|
||||
- `c`
|
||||
`.`
|
||||
`~`
|
||||
True if the current path, with prefix replacement, has at least
|
||||
`n` elements relative to the root directory, hence `/` is
|
||||
counted as 0 elements.
|
||||
c
|
||||
.
|
||||
\~
|
||||
True if the current path, with prefix replacement, has at least `n`
|
||||
elements relative to the root directory, hence / is counted as 0
|
||||
elements.
|
||||
|
||||
- `D`
|
||||
True if the month is equal to `n` (January = 0).
|
||||
D
|
||||
True if the month is equal to `n` (January = 0).
|
||||
|
||||
- `d`
|
||||
True if the day of the month is equal to `n`.
|
||||
d
|
||||
True if the day of the month is equal to `n`.
|
||||
|
||||
- `e`
|
||||
True if the evaluation depth is at least `n`.
|
||||
e
|
||||
True if the evaluation depth is at least `n`.
|
||||
|
||||
- `g`
|
||||
True if the effective gid of the current process is `n`.
|
||||
g
|
||||
True if the effective gid of the current process is `n`.
|
||||
|
||||
- `j`
|
||||
True if the number of jobs is at least `n`.
|
||||
j
|
||||
True if the number of jobs is at least `n`.
|
||||
|
||||
- `L`
|
||||
True if the `SHLVL` parameter is at least `n`.
|
||||
L
|
||||
True if the SHLVL parameter is at least `n`.
|
||||
|
||||
- `l`
|
||||
True if at least `n` characters have already been printed on the
|
||||
current line. When `n` is negative, true if at least
|
||||
`abs``(``n``)` characters remain before the opposite margin
|
||||
(thus the left margin for `RPROMPT`).
|
||||
l
|
||||
True if at least `n` characters have already been printed on the current
|
||||
line. When `n` is negative, true if at least abs(`n`) characters remain
|
||||
before the opposite margin (thus the left margin for RPROMPT).
|
||||
|
||||
- `S`
|
||||
True if the `SECONDS` parameter is at least `n`.
|
||||
S
|
||||
True if the SECONDS parameter is at least `n`.
|
||||
|
||||
- `T`
|
||||
True if the time in hours is equal to `n`.
|
||||
T
|
||||
True if the time in hours is equal to `n`.
|
||||
|
||||
- `t`
|
||||
True if the time in minutes is equal to `n`.
|
||||
t
|
||||
True if the time in minutes is equal to `n`.
|
||||
|
||||
- `v`
|
||||
True if the array `psvar` has at least `n` elements.
|
||||
v
|
||||
True if the array psvar has at least `n` elements.
|
||||
|
||||
- `V`
|
||||
True if element `n` of the array `psvar` is set and non-empty.
|
||||
V
|
||||
True if element `n` of the array psvar is set and non-empty.
|
||||
|
||||
- `w`
|
||||
True if the day of the week is equal to `n` (Sunday = 0).
|
||||
w
|
||||
True if the day of the week is equal to `n` (Sunday = 0).
|
||||
|
||||
- `%<``string``<`
|
||||
`%>``string``>`
|
||||
`%[``xstring``]`
|
||||
Specifies truncation behaviour for the remainder of the prompt
|
||||
string. The third, deprecated, form is equivalent to
|
||||
‘`%``xstringx`’, i.e. `x` may be ‘`<`’ or ‘`>`’. The `string`
|
||||
will be displayed in place of the truncated portion of any string;
|
||||
note this does not undergo prompt expansion.
|
||||
%\<`string`\<
|
||||
%>`string`\>
|
||||
%\[`xstring`\]
|
||||
Specifies truncation behaviour for the remainder of the prompt string.
|
||||
The third, deprecated, form is equivalent to ‘%`xstringx`’, i.e. `x` may
|
||||
be ‘\<’ or ‘>’. The `string` will be displayed in place of the truncated
|
||||
portion of any string; note this does not undergo prompt expansion.
|
||||
|
||||
The numeric argument, which in the third form may appear immediately
|
||||
after the ‘`[`’, specifies the maximum permitted length of the
|
||||
various strings that can be displayed in the prompt. In the first
|
||||
two forms, this numeric argument may be negative, in which case the
|
||||
truncation length is determined by subtracting the absolute value of
|
||||
the numeric argument from the number of character positions
|
||||
remaining on the current prompt line. If this results in a zero or
|
||||
negative length, a length of 1 is used. In other words, a negative
|
||||
argument arranges that after truncation at least `n` characters
|
||||
remain before the right margin (left margin for `RPROMPT`).
|
||||
The numeric argument, which in the third form may appear immediately
|
||||
after the ‘\[’, specifies the maximum permitted length of the various
|
||||
strings that can be displayed in the prompt. In the first two forms,
|
||||
this numeric argument may be negative, in which case the truncation
|
||||
length is determined by subtracting the absolute value of the numeric
|
||||
argument from the number of character positions remaining on the current
|
||||
prompt line. If this results in a zero or negative length, a length of 1
|
||||
is used. In other words, a negative argument arranges that after
|
||||
truncation at least `n` characters remain before the right margin (left
|
||||
margin for RPROMPT).
|
||||
|
||||
The forms with ‘`<`’ truncate at the left of the string, and the
|
||||
forms with ‘`>`’ truncate at the right of the string. For example,
|
||||
if the current directory is ‘`/home/pike`’, the prompt ‘`%8<..<%/`’
|
||||
will expand to ‘`..e/pike`’. In this string, the terminating
|
||||
character (‘`<`’, ‘`>`’ or ‘`]`’), or in fact any character, may be
|
||||
quoted by a preceding ‘`\`’; note when using `print -P`, however,
|
||||
that this must be doubled as the string is also subject to standard
|
||||
`print` processing, in addition to any backslashes removed by a
|
||||
double quoted string: the worst case is therefore ‘`print -P
|
||||
"%<\\\\<<..."`’.
|
||||
The forms with ‘\<’ truncate at the left of the string, and the forms
|
||||
with ‘>’ truncate at the right of the string. For example, if the
|
||||
current directory is ‘/home/pike’, the prompt ‘%8\<..\<%/’ will expand
|
||||
to ‘..e/pike’. In this string, the terminating character (‘\<’, ‘>’ or
|
||||
‘\]’), or in fact any character, may be quoted by a preceding ‘\\’; note
|
||||
when using print -P, however, that this must be doubled as the string is
|
||||
also subject to standard print processing, in addition to any
|
||||
backslashes removed by a double quoted string: the worst case is
|
||||
therefore ‘print -P "%\<\\\\\\\\\<\<..."’.
|
||||
|
||||
If the `string` is longer than the specified truncation length, it
|
||||
will appear in full, completely replacing the truncated string.
|
||||
If the `string` is longer than the specified truncation length, it will
|
||||
appear in full, completely replacing the truncated string.
|
||||
|
||||
The part of the prompt string to be truncated runs to the end of the
|
||||
string, or to the end of the next enclosing group of the ‘`%(`’
|
||||
construct, or to the next truncation encountered at the same
|
||||
grouping level (i.e. truncations inside a ‘`%(`’ are separate),
|
||||
which ever comes first. In particular, a truncation with argument
|
||||
zero (e.g., ‘`%<<`’) marks the end of the range of the string to be
|
||||
truncated while turning off truncation from there on. For example,
|
||||
the prompt ‘` %10<...<%~%<<%# `’ will print a truncated
|
||||
representation of the current directory, followed by a ‘`%`’ or
|
||||
‘`#`’, followed by a space. Without the ‘`%<<`’, those two
|
||||
characters would be included in the string to be truncated. Note
|
||||
that ‘`%-0<<`’ is not equivalent to ‘`%<<`’ but specifies that the
|
||||
prompt is truncated at the right margin.
|
||||
The part of the prompt string to be truncated runs to the end of the
|
||||
string, or to the end of the next enclosing group of the ‘%(’ construct,
|
||||
or to the next truncation encountered at the same grouping level (i.e.
|
||||
truncations inside a ‘%(’ are separate), which ever comes first. In
|
||||
particular, a truncation with argument zero (e.g., ‘%\<\<’) marks the
|
||||
end of the range of the string to be truncated while turning off
|
||||
truncation from there on. For example, the prompt ‘%10\<...\<%\~%\<\<%#
|
||||
’ will print a truncated representation of the current directory,
|
||||
followed by a ‘%’ or ‘#’, followed by a space. Without the ‘%\<\<’,
|
||||
those two characters would be included in the string to be truncated.
|
||||
Note that ‘%-0\<\<’ is not equivalent to ‘%\<\<’ but specifies that the
|
||||
prompt is truncated at the right margin.
|
||||
|
||||
Truncation applies only within each individual line of the prompt,
|
||||
as delimited by embedded newlines (if any). If the total length of
|
||||
any line of the prompt after truncation is greater than the terminal
|
||||
width, or if the part to be truncated contains embedded newlines,
|
||||
truncation behavior is undefined and may change in a future version
|
||||
of the shell. Use ‘`%-``n``(l.``true-text``.``false-text``)`’ to
|
||||
remove parts of the prompt when the available space is less than
|
||||
`n`.
|
||||
Truncation applies only within each individual line of the prompt, as
|
||||
delimited by embedded newlines (if any). If the total length of any line
|
||||
of the prompt after truncation is greater than the terminal width, or if
|
||||
the part to be truncated contains embedded newlines, truncation behavior
|
||||
is undefined and may change in a future version of the shell. Use
|
||||
‘%-`n`(l.`true-text`.`false-text`)’ to remove parts of the prompt when
|
||||
the available space is less than `n`.
|
||||
|
||||
-----
|
||||
------------------------------------------------------------------------
|
||||
|
||||
This document was generated on *February 15, 2020* using
|
||||
[*texi2html 5.0*](http://www.nongnu.org/texi2html/).
|
||||
Zsh version 5.8, released on February 14, 2020.
|
||||
This document was generated on *May 14, 2022* using [*texi2html
|
||||
5.0*](http://www.nongnu.org/texi2html/).
|
||||
Zsh version 5.9, released on May 14, 2022.
|
||||
|
||||
@ -13,12 +13,12 @@
|
||||
|
||||
# 7 Redirection
|
||||
|
||||
<span id="index-redirection"></span>
|
||||
<span id="index-file-descriptors"></span>
|
||||
<span id="index-descriptors_002c-file"></span>
|
||||
<span id="index-redirection"></span> <span
|
||||
id="index-file-descriptors"></span> <span
|
||||
id="index-descriptors_002c-file"></span>
|
||||
|
||||
If a command is followed by `&` and job control is not active, then the
|
||||
default standard input for the command is the empty file `/dev/null`.
|
||||
If a command is followed by & and job control is not active, then the
|
||||
default standard input for the command is the empty file /dev/null.
|
||||
Otherwise, the environment for the execution of a command contains the
|
||||
file descriptors of the invoking shell as modified by input/output
|
||||
specifications.
|
||||
@ -29,107 +29,103 @@ used except as noted below. If the result of substitution on `word`
|
||||
produces more than one filename, redirection occurs for each separate
|
||||
filename in turn.
|
||||
|
||||
- `<` `word`
|
||||
Open file `word` for reading as standard input. It is an error to
|
||||
open a file in this fashion if it does not exist.
|
||||
\< `word`
|
||||
Open file `word` for reading as standard input. It is an error to open a
|
||||
file in this fashion if it does not exist.
|
||||
|
||||
- `<>` `word`
|
||||
Open file `word` for reading and writing as standard input. If the
|
||||
file does not exist then it is created.
|
||||
\<\> `word`
|
||||
Open file `word` for reading and writing as standard input. If the file
|
||||
does not exist then it is created.
|
||||
|
||||
- `>` `word`
|
||||
Open file `word` for writing as standard output. If the file does
|
||||
not exist then it is created. If the file exists, and the `CLOBBER`
|
||||
option is unset, this causes an error; otherwise, it is truncated to
|
||||
zero length.
|
||||
\> `word`
|
||||
Open file `word` for writing as standard output. If the file does not
|
||||
exist then it is created. If the file exists, and the CLOBBER option is
|
||||
unset, this causes an error; otherwise, it is truncated to zero length.
|
||||
|
||||
- `>|` `word`
|
||||
`>!` `word`
|
||||
Same as `>`, except that the file is truncated to zero length if it
|
||||
exists, regardless of `CLOBBER`.
|
||||
\>\| `word`
|
||||
\>! `word`
|
||||
Same as >, except that the file is truncated to zero length if it
|
||||
exists, regardless of CLOBBER.
|
||||
|
||||
- `>>` `word`
|
||||
Open file `word` for writing in append mode as standard output. If
|
||||
the file does not exist, and the `CLOBBER` and `APPEND_CREATE`
|
||||
options are both unset, this causes an error; otherwise, the file is
|
||||
created.
|
||||
\>\> `word`
|
||||
Open file `word` for writing in append mode as standard output. If the
|
||||
file does not exist, and the CLOBBER and APPEND_CREATE options are both
|
||||
unset, this causes an error; otherwise, the file is created.
|
||||
|
||||
- `>>|` `word`
|
||||
`>>!` `word`
|
||||
Same as `>>`, except that the file is created if it does not exist,
|
||||
regardless of `CLOBBER` and `APPEND_CREATE`.
|
||||
\>\>\| `word`
|
||||
\>\>! `word`
|
||||
Same as >\>, except that the file is created if it does not exist,
|
||||
regardless of CLOBBER and APPEND_CREATE.
|
||||
|
||||
- `<<`\[`-`\] `word`
|
||||
The shell input is read up to a line that is the same as `word`, or
|
||||
to an end-of-file. No parameter expansion, command substitution or
|
||||
filename generation is performed on `word`. The resulting document,
|
||||
called a *here-document*, becomes the standard input.
|
||||
\<\<\[-\] `word`
|
||||
The shell input is read up to a line that is the same as `word`, or to
|
||||
an end-of-file. No parameter expansion, command substitution or filename
|
||||
generation is performed on `word`. The resulting document, called a
|
||||
*here-document*, becomes the standard input.
|
||||
|
||||
If any character of `word` is quoted with single or double quotes or
|
||||
a ‘`\`’, no interpretation is placed upon the characters of the
|
||||
document. Otherwise, parameter and command substitution occurs,
|
||||
‘`\`’ followed by a newline is removed, and ‘`\`’ must be used
|
||||
to quote the characters ‘`\`’, ‘`$`’, ‘`‘`’ and the first character
|
||||
of `word`.
|
||||
If any character of `word` is quoted with single or double quotes or a
|
||||
‘\\’, no interpretation is placed upon the characters of the document.
|
||||
Otherwise, parameter and command substitution occurs, ‘\\’ followed by a
|
||||
newline is removed, and ‘\\’ must be used to quote the characters ‘\\’,
|
||||
‘$’, ‘‘’ and the first character of `word`.
|
||||
|
||||
Note that `word` itself does not undergo shell expansion. Backquotes
|
||||
in `word` do not have their usual effect; instead they behave
|
||||
similarly to double quotes, except that the backquotes themselves
|
||||
are passed through unchanged. (This information is given for
|
||||
completeness and it is not recommended that backquotes be used.)
|
||||
Quotes in the form `$’``...``’` have their standard effect of
|
||||
expanding backslashed references to special characters.
|
||||
Note that `word` itself does not undergo shell expansion. Backquotes in
|
||||
`word` do not have their usual effect; instead they behave similarly to
|
||||
double quotes, except that the backquotes themselves are passed through
|
||||
unchanged. (This information is given for completeness and it is not
|
||||
recommended that backquotes be used.) Quotes in the form $’`...`’ have
|
||||
their standard effect of expanding backslashed references to special
|
||||
characters.
|
||||
|
||||
If `<<-` is used, then all leading tabs are stripped from `word` and
|
||||
from the document.
|
||||
If \<\<- is used, then all leading tabs are stripped from `word` and
|
||||
from the document.
|
||||
|
||||
- `<<<` `word`
|
||||
Perform shell expansion on `word` and pass the result to standard
|
||||
input. This is known as a *here-string*. Compare the use of `word`
|
||||
in here-documents above, where `word` does not undergo shell
|
||||
expansion.
|
||||
\<\<\< `word`
|
||||
Perform shell expansion on `word` and pass the result to standard input.
|
||||
This is known as a *here-string*. Compare the use of `word` in
|
||||
here-documents above, where `word` does not undergo shell expansion. The
|
||||
result will have a trailing newline after it.
|
||||
|
||||
- `<&` `number`
|
||||
`>&` `number`
|
||||
The standard input/output is duplicated from file descriptor
|
||||
`number` (see man page dup2(2)).
|
||||
\<& `number`
|
||||
\>& `number`
|
||||
The standard input/output is duplicated from file descriptor `number`
|
||||
(see dup2(2)).
|
||||
|
||||
- `<& -`
|
||||
`>& -`
|
||||
Close the standard input/output.
|
||||
\<& -
|
||||
\>& -
|
||||
Close the standard input/output.
|
||||
|
||||
- `<& p`
|
||||
`>& p`
|
||||
The input/output from/to the coprocess is moved to the standard
|
||||
input/output.
|
||||
\<& p
|
||||
\>& p
|
||||
The input/output from/to the coprocess is moved to the standard
|
||||
input/output.
|
||||
|
||||
- `>&` `word`
|
||||
`&>` `word`
|
||||
(Except where ‘`>&` `word`’ matches one of the above syntaxes;
|
||||
‘`&>`’ can always be used to avoid this ambiguity.) Redirects
|
||||
both standard output and standard error (file descriptor 2) in the
|
||||
manner of ‘`>` `word`’. Note that this does *not* have the same
|
||||
effect as ‘`>` `word` `2>&1`’ in the presence of multios (see the
|
||||
section below).
|
||||
\>& `word`
|
||||
&> `word`
|
||||
(Except where ‘>& `word`’ matches one of the above syntaxes; ‘&>’ can
|
||||
always be used to avoid this ambiguity.) Redirects both standard output
|
||||
and standard error (file descriptor 2) in the manner of ‘> `word`’. Note
|
||||
that this does *not* have the same effect as ‘> `word` 2>&1’ in the
|
||||
presence of multios (see the section below).
|
||||
|
||||
- `>&|` `word`
|
||||
`>&!` `word`
|
||||
`&>|` `word`
|
||||
`&>!` `word`
|
||||
Redirects both standard output and standard error (file descriptor
|
||||
2) in the manner of ‘`>|` `word`’.
|
||||
\>&\| `word`
|
||||
\>&! `word`
|
||||
&>\| `word`
|
||||
&>! `word`
|
||||
Redirects both standard output and standard error (file descriptor 2) in
|
||||
the manner of ‘>\| `word`’.
|
||||
|
||||
- `>>&` `word`
|
||||
`&>>` `word`
|
||||
Redirects both standard output and standard error (file descriptor
|
||||
2) in the manner of ‘`>>` `word`’.
|
||||
\>\>& `word`
|
||||
&>\> `word`
|
||||
Redirects both standard output and standard error (file descriptor 2) in
|
||||
the manner of ‘>\> `word`’.
|
||||
|
||||
- `>>&|` `word`
|
||||
`>>&!` `word`
|
||||
`&>>|` `word`
|
||||
`&>>!` `word`
|
||||
Redirects both standard output and standard error (file descriptor
|
||||
2) in the manner of ‘`>>|` `word`’.
|
||||
\>\>&\| `word`
|
||||
\>\>&! `word`
|
||||
&>\>\| `word`
|
||||
&>\>! `word`
|
||||
Redirects both standard output and standard error (file descriptor 2) in
|
||||
the manner of ‘>\>\| `word`’.
|
||||
|
||||
If one of the above is preceded by a digit, then the file descriptor
|
||||
referred to is that specified by the digit instead of the default 0 or
|
||||
@ -137,7 +133,7 @@ referred to is that specified by the digit instead of the default 0 or
|
||||
shell evaluates each redirection in terms of the (*file descriptor*,
|
||||
*file*) association at the time of evaluation. For example:
|
||||
|
||||
> ... `1>``fname` `2>&1`
|
||||
> ... 1>`fname` 2>&1
|
||||
|
||||
first associates file descriptor 1 with file `fname`. It then associates
|
||||
file descriptor 2 with the file associated with file descriptor 1 (that
|
||||
@ -146,62 +142,58 @@ descriptor 2 would be associated with the terminal (assuming file
|
||||
descriptor 1 had been) and then file descriptor 1 would be associated
|
||||
with file `fname`.
|
||||
|
||||
The ‘`|&`’ command separator described in [Simple Commands &
|
||||
The ‘\|&’ command separator described in [Simple Commands &
|
||||
Pipelines](Shell-Grammar.html#Simple-Commands-_0026-Pipelines) is a
|
||||
shorthand for ‘`2>&1 |`’.
|
||||
shorthand for ‘2>&1 \|’.
|
||||
|
||||
The various forms of process substitution, ‘`<(``list``)`’, and
|
||||
‘`=(``list``)`’ for input and ‘`>(``list``)`’ for output, are often
|
||||
used together with redirection. For example, if `word` in an output
|
||||
redirection is of the form ‘`>(``list``)`’ then the output is piped to
|
||||
the command represented by `list`. See [Process
|
||||
Substitution](Expansion.html#Process-Substitution).
|
||||
The various forms of process substitution, ‘\<(`list`)’, and ‘=(`list`)’
|
||||
for input and ‘>(`list`)’ for output, are often used together with
|
||||
redirection. For example, if `word` in an output redirection is of the
|
||||
form ‘>(`list`)’ then the output is piped to the command represented by
|
||||
`list`. See [Process Substitution](Expansion.html#Process-Substitution).
|
||||
|
||||
-----
|
||||
------------------------------------------------------------------------
|
||||
|
||||
<span id="Opening-file-descriptors-using-parameters"></span>
|
||||
|
||||
## 7.1 Opening file descriptors using parameters
|
||||
|
||||
<span id="index-file-descriptors_002c-use-with-parameters"></span>
|
||||
<span id="index-parameters_002c-for-using-file-descriptors"></span>
|
||||
<span id="index-file-descriptors_002c-use-with-parameters"></span> <span
|
||||
id="index-parameters_002c-for-using-file-descriptors"></span>
|
||||
|
||||
When the shell is parsing arguments to a command, and the shell option
|
||||
`IGNORE_BRACES` is not set, a different form of redirection is allowed:
|
||||
IGNORE_BRACES is not set, a different form of redirection is allowed:
|
||||
instead of a digit before the operator there is a valid shell identifier
|
||||
enclosed in braces. The shell will open a new file descriptor that is
|
||||
guaranteed to be at least 10 and set the parameter named by the
|
||||
identifier to the file descriptor opened. No whitespace is allowed
|
||||
between the closing brace and the redirection character. For example:
|
||||
|
||||
> ... `{myfd}>&1`
|
||||
> ... {myfd}>&1
|
||||
|
||||
This opens a new file descriptor that is a duplicate of file descriptor
|
||||
1 and sets the parameter `myfd` to the number of the file descriptor,
|
||||
1 and sets the parameter myfd to the number of the file descriptor,
|
||||
which will be at least 10. The new file descriptor can be written to
|
||||
using the syntax `>&$myfd`. The file descriptor remains open in
|
||||
subshells
|
||||
using the syntax \>&$myfd. The file descriptor remains open in subshells
|
||||
|
||||
The syntax `{``varid``}>&-`, for example `{myfd}>&-`, may be used to
|
||||
close a file descriptor opened in this fashion. Note that the parameter
|
||||
given by `varid` must previously be set to a file descriptor in this
|
||||
case.
|
||||
The syntax {`varid`}>&-, for example {myfd}>&-, may be used to close a
|
||||
file descriptor opened in this fashion. Note that the parameter given by
|
||||
`varid` must previously be set to a file descriptor in this case.
|
||||
|
||||
It is an error to open or close a file descriptor in this fashion when
|
||||
the parameter is readonly. However, it is not an error to read or write
|
||||
a file descriptor using `<&$``param` or `>&$``param` if `param` is
|
||||
a file descriptor using \<&$`param` or \>&$`param` if `param` is
|
||||
readonly.
|
||||
|
||||
If the option `CLOBBER` is unset, it is an error to open a file
|
||||
descriptor using a parameter that is already set to an open file
|
||||
descriptor previously allocated by this mechanism. Unsetting the
|
||||
parameter before using it for allocating a file descriptor avoids the
|
||||
error.
|
||||
If the option CLOBBER is unset, it is an error to open a file descriptor
|
||||
using a parameter that is already set to an open file descriptor
|
||||
previously allocated by this mechanism. Unsetting the parameter before
|
||||
using it for allocating a file descriptor avoids the error.
|
||||
|
||||
Note that this mechanism merely allocates or closes a file descriptor;
|
||||
it does not perform any redirections from or to it. It is usually
|
||||
convenient to allocate a file descriptor prior to use as an argument to
|
||||
`exec`. The syntax does not in any case work when used around complex
|
||||
exec. The syntax does not in any case work when used around complex
|
||||
commands such as parenthesised subshells or loops, where the opening
|
||||
brace is interpreted as part of a command list to be executed in the
|
||||
current shell.
|
||||
@ -211,7 +203,7 @@ of a file descriptor:
|
||||
|
||||
<div class="example">
|
||||
|
||||
``` example
|
||||
```zsh
|
||||
integer myfd
|
||||
exec {myfd}>~/logs/mylogfile.txt
|
||||
print This is a log message. >&$myfd
|
||||
@ -220,97 +212,96 @@ exec {myfd}>&-
|
||||
|
||||
</div>
|
||||
|
||||
Note that the expansion of the variable in the expression `>&$myfd`
|
||||
Note that the expansion of the variable in the expression \>&$myfd
|
||||
occurs at the point the redirection is opened. This is after the
|
||||
expansion of command arguments and after any redirections to the left on
|
||||
the command line have been processed.
|
||||
|
||||
-----
|
||||
------------------------------------------------------------------------
|
||||
|
||||
<span id="Multios"></span>
|
||||
|
||||
## 7.2 Multios
|
||||
|
||||
<span id="index-multios"></span>
|
||||
<span id="index-MULTIOS_002c-use-of"></span>
|
||||
<span id="index-multios"></span> <span
|
||||
id="index-MULTIOS_002c-use-of"></span>
|
||||
|
||||
If the user tries to open a file descriptor for writing more than once,
|
||||
the shell opens the file descriptor as a pipe to a process that copies
|
||||
its input to all the specified outputs, similar to tee, provided the
|
||||
`MULTIOS` option is set, as it is by default. Thus:
|
||||
MULTIOS option is set, as it is by default. Thus:
|
||||
|
||||
<div class="example">
|
||||
|
||||
``` example
|
||||
```zsh
|
||||
date >foo >bar
|
||||
```
|
||||
|
||||
</div>
|
||||
|
||||
writes the date to two files, named ‘`foo`’ and ‘`bar`’. Note that a
|
||||
pipe is an implicit redirection; thus
|
||||
writes the date to two files, named ‘foo’ and ‘bar’. Note that a pipe is
|
||||
an implicit redirection; thus
|
||||
|
||||
<div class="example">
|
||||
|
||||
``` example
|
||||
```zsh
|
||||
date >foo | cat
|
||||
```
|
||||
|
||||
</div>
|
||||
|
||||
writes the date to the file ‘`foo`’, and also pipes it to cat.
|
||||
writes the date to the file ‘foo’, and also pipes it to cat.
|
||||
|
||||
Note that the shell opens all the files to be used in the multio process
|
||||
immediately, not at the point they are about to be written.
|
||||
|
||||
Note also that redirections are always expanded in order. This happens
|
||||
regardless of the setting of the `MULTIOS` option, but with the option
|
||||
in effect there are additional consequences. For example, the meaning of
|
||||
the expression `>&1` will change after a previous redirection:
|
||||
regardless of the setting of the MULTIOS option, but with the option in
|
||||
effect there are additional consequences. For example, the meaning of
|
||||
the expression \>&1 will change after a previous redirection:
|
||||
|
||||
<div class="example">
|
||||
|
||||
``` example
|
||||
```zsh
|
||||
date >&1 >output
|
||||
```
|
||||
|
||||
</div>
|
||||
|
||||
In the case above, the `>&1` refers to the standard output at the start
|
||||
of the line; the result is similar to the `tee` command. However,
|
||||
In the case above, the \>&1 refers to the standard output at the start
|
||||
of the line; the result is similar to the tee command. However,
|
||||
consider:
|
||||
|
||||
<div class="example">
|
||||
|
||||
``` example
|
||||
```zsh
|
||||
date >output >&1
|
||||
```
|
||||
|
||||
</div>
|
||||
|
||||
As redirections are evaluated in order, when the `>&1` is encountered
|
||||
the standard output is set to the file `output` and another copy of the
|
||||
output is therefore sent to that file. This is unlikely to be what is
|
||||
intended.
|
||||
As redirections are evaluated in order, when the \>&1 is encountered the
|
||||
standard output is set to the file output and another copy of the output
|
||||
is therefore sent to that file. This is unlikely to be what is intended.
|
||||
|
||||
If the `MULTIOS` option is set, the word after a redirection operator is
|
||||
If the MULTIOS option is set, the word after a redirection operator is
|
||||
also subjected to filename generation (globbing). Thus
|
||||
|
||||
<div class="example">
|
||||
|
||||
``` example
|
||||
```zsh
|
||||
: > *
|
||||
```
|
||||
|
||||
</div>
|
||||
|
||||
will truncate all files in the current directory, assuming there’s at
|
||||
least one. (Without the `MULTIOS` option, it would create an empty file
|
||||
called ‘`*`’.) Similarly, you can do
|
||||
least one. (Without the MULTIOS option, it would create an empty file
|
||||
called ‘\*’.) Similarly, you can do
|
||||
|
||||
<div class="example">
|
||||
|
||||
``` example
|
||||
```zsh
|
||||
echo exit 0 >> *.sh
|
||||
```
|
||||
|
||||
@ -319,16 +310,16 @@ echo exit 0 >> *.sh
|
||||
If the user tries to open a file descriptor for reading more than once,
|
||||
the shell opens the file descriptor as a pipe to a process that copies
|
||||
all the specified inputs to its output in the order specified, provided
|
||||
the `MULTIOS` option is set. It should be noted that each file is opened
|
||||
the MULTIOS option is set. It should be noted that each file is opened
|
||||
immediately, not at the point where it is about to be read: this
|
||||
behaviour differs from `cat`, so if strictly standard behaviour is
|
||||
needed, `cat` should be used instead.
|
||||
behaviour differs from cat, so if strictly standard behaviour is needed,
|
||||
cat should be used instead.
|
||||
|
||||
Thus
|
||||
|
||||
<div class="example">
|
||||
|
||||
``` example
|
||||
```zsh
|
||||
sort <foo <fubar
|
||||
```
|
||||
|
||||
@ -338,80 +329,78 @@ or even
|
||||
|
||||
<div class="example">
|
||||
|
||||
``` example
|
||||
```zsh
|
||||
sort <f{oo,ubar}
|
||||
```
|
||||
|
||||
</div>
|
||||
|
||||
is equivalent to ‘`cat foo fubar | sort`’.
|
||||
is equivalent to ‘cat foo fubar \| sort’.
|
||||
|
||||
Expansion of the redirection argument occurs at the point the
|
||||
redirection is opened, at the point described above for the expansion of
|
||||
the variable in `>&$myfd`.
|
||||
the variable in \>&$myfd.
|
||||
|
||||
Note that a pipe is an implicit redirection; thus
|
||||
|
||||
<div class="example">
|
||||
|
||||
``` example
|
||||
```zsh
|
||||
cat bar | sort <foo
|
||||
```
|
||||
|
||||
</div>
|
||||
|
||||
is equivalent to ‘`cat bar foo | sort`’ (note the order of the inputs).
|
||||
is equivalent to ‘cat bar foo \| sort’ (note the order of the inputs).
|
||||
|
||||
If the `MULTIOS` option is *un*set, each redirection replaces the
|
||||
previous redirection for that file descriptor. However, all files
|
||||
redirected to are actually opened, so
|
||||
If the MULTIOS option is *un*set, each redirection replaces the previous
|
||||
redirection for that file descriptor. However, all files redirected to
|
||||
are actually opened, so
|
||||
|
||||
<div class="example">
|
||||
|
||||
``` example
|
||||
```zsh
|
||||
echo Hello > bar > baz
|
||||
```
|
||||
|
||||
</div>
|
||||
|
||||
when `MULTIOS` is unset will truncate ‘`bar`’, and write ‘`Hello`’ into
|
||||
‘`baz`’.
|
||||
when MULTIOS is unset will truncate ‘bar’, and write ‘Hello’ into ‘baz’.
|
||||
|
||||
There is a problem when an output multio is attached to an external
|
||||
program. A simple example shows this:
|
||||
|
||||
<div class="example">
|
||||
|
||||
``` example
|
||||
```zsh
|
||||
cat file >file1 >file2
|
||||
cat file1 file2
|
||||
```
|
||||
|
||||
</div>
|
||||
|
||||
Here, it is possible that the second ‘`cat`’ will not display the full
|
||||
contents of `file1` and `file2` (i.e. the original contents of `file`
|
||||
repeated twice).
|
||||
Here, it is possible that the second ‘cat’ will not display the full
|
||||
contents of file1 and file2 (i.e. the original contents of file repeated
|
||||
twice).
|
||||
|
||||
The reason for this is that the multios are spawned after the `cat`
|
||||
The reason for this is that the multios are spawned after the cat
|
||||
process is forked from the parent shell, so the parent shell does not
|
||||
wait for the multios to finish writing data. This means the command as
|
||||
shown can exit before `file1` and `file2` are completely written. As a
|
||||
workaround, it is possible to run the `cat` process as part of a job in
|
||||
shown can exit before file1 and file2 are completely written. As a
|
||||
workaround, it is possible to run the cat process as part of a job in
|
||||
the current shell:
|
||||
|
||||
<div class="example">
|
||||
|
||||
``` example
|
||||
```zsh
|
||||
{ cat file } >file >file2
|
||||
```
|
||||
|
||||
</div>
|
||||
|
||||
Here, the `{``...``}` job will pause to wait for both files to be
|
||||
written.
|
||||
Here, the {`...`} job will pause to wait for both files to be written.
|
||||
|
||||
-----
|
||||
------------------------------------------------------------------------
|
||||
|
||||
<span id="Redirections-with-no-command"></span>
|
||||
|
||||
@ -421,40 +410,40 @@ When a simple command consists of one or more redirection operators and
|
||||
zero or more parameter assignments, but no command name, zsh can behave
|
||||
in several ways.
|
||||
|
||||
<span id="index-NULLCMD_002c-use-of"></span>
|
||||
<span id="index-CSH_005fNULLCMD_002c-use-of"></span>
|
||||
<span id="index-NULLCMD_002c-use-of"></span> <span
|
||||
id="index-CSH_005fNULLCMD_002c-use-of"></span>
|
||||
|
||||
If the parameter `NULLCMD` is not set or the option `CSH_NULLCMD` is
|
||||
set, an error is caused. This is the csh behavior and `CSH_NULLCMD` is
|
||||
set by default when emulating csh.
|
||||
If the parameter NULLCMD is not set or the option CSH_NULLCMD is set, an
|
||||
error is caused. This is the csh behavior and CSH_NULLCMD is set by
|
||||
default when emulating csh.
|
||||
|
||||
<span id="index-SH_005fNULLCMD_002c-use-of"></span>
|
||||
|
||||
If the option `SH_NULLCMD` is set, the builtin ‘`:`’ is inserted as a
|
||||
If the option SH_NULLCMD is set, the builtin ‘:’ is inserted as a
|
||||
command with the given redirections. This is the default when emulating
|
||||
sh or ksh.
|
||||
|
||||
<span id="index-READNULLCMD_002c-use-of"></span>
|
||||
|
||||
Otherwise, if the parameter `NULLCMD` is set, its value will be used as
|
||||
a command with the given redirections. If both `NULLCMD` and
|
||||
`READNULLCMD` are set, then the value of the latter will be used instead
|
||||
of that of the former when the redirection is an input. The default for
|
||||
`NULLCMD` is ‘`cat`’ and for `READNULLCMD` is ‘`more`’. Thus
|
||||
Otherwise, if the parameter NULLCMD is set, its value will be used as a
|
||||
command with the given redirections. If both NULLCMD and READNULLCMD are
|
||||
set, then the value of the latter will be used instead of that of the
|
||||
former when the redirection is an input. The default for NULLCMD is
|
||||
‘cat’ and for READNULLCMD is ‘more’. Thus
|
||||
|
||||
<div class="example">
|
||||
|
||||
``` example
|
||||
```zsh
|
||||
< file
|
||||
```
|
||||
|
||||
</div>
|
||||
|
||||
shows the contents of `file` on standard output, with paging if that is
|
||||
a terminal. `NULLCMD` and `READNULLCMD` may refer to shell functions.
|
||||
shows the contents of file on standard output, with paging if that is a
|
||||
terminal. NULLCMD and READNULLCMD may refer to shell functions.
|
||||
|
||||
-----
|
||||
------------------------------------------------------------------------
|
||||
|
||||
This document was generated on *February 15, 2020* using
|
||||
[*texi2html 5.0*](http://www.nongnu.org/texi2html/).
|
||||
Zsh version 5.8, released on February 14, 2020.
|
||||
This document was generated on *May 14, 2022* using [*texi2html
|
||||
5.0*](http://www.nongnu.org/texi2html/).
|
||||
Zsh version 5.9, released on May 14, 2022.
|
||||
|
||||
@ -25,7 +25,7 @@ This section of the manual provides some pointers to areas of the shell
|
||||
that are likely to be of particular interest to new users, and indicates
|
||||
where in the rest of the manual the documentation is to be found.
|
||||
|
||||
-----
|
||||
------------------------------------------------------------------------
|
||||
|
||||
<span id="When-the-shell-starts"></span>
|
||||
|
||||
@ -37,13 +37,13 @@ be created or edited to customize the shell. See
|
||||
|
||||
If no personal initialization files exist for the current user, a
|
||||
function is run to help you change some of the most common settings. It
|
||||
won’t appear if your administrator has disabled the `zsh/newuser`
|
||||
module. The function is designed to be self-explanatory. You can run it
|
||||
by hand with ‘`autoload -Uz zsh-newuser-install; zsh-newuser-install
|
||||
-f`’. See also [User Configuration
|
||||
won’t appear if your administrator has disabled the zsh/newuser module.
|
||||
The function is designed to be self-explanatory. You can run it by hand
|
||||
with ‘autoload -Uz zsh-newuser-install; zsh-newuser-install -f’. See
|
||||
also [User Configuration
|
||||
Functions](User-Contributions.html#User-Configuration-Functions).
|
||||
|
||||
-----
|
||||
------------------------------------------------------------------------
|
||||
|
||||
<span id="Interactive-Use"></span>
|
||||
|
||||
@ -56,15 +56,15 @@ Editor](Zsh-Line-Editor.html#Zsh-Line-Editor).
|
||||
The first decision a user must make is whether to use the Emacs or Vi
|
||||
editing mode as the keys for editing are substantially different. Emacs
|
||||
editing mode is probably more natural for beginners and can be selected
|
||||
explicitly with the command `bindkey -e`.
|
||||
explicitly with the command bindkey -e.
|
||||
|
||||
A history mechanism for retrieving previously typed lines (most simply
|
||||
with the Up or Down arrow keys) is available; note that, unlike other
|
||||
shells, zsh will not save these lines when the shell exits unless you
|
||||
set appropriate variables, and the number of history lines retained by
|
||||
default is quite small (30 lines). See the description of the shell
|
||||
variables (referred to in the documentation as parameters) `HISTFILE`,
|
||||
`HISTSIZE` and `SAVEHIST` in [Parameters Used By The
|
||||
variables (referred to in the documentation as parameters) HISTFILE,
|
||||
HISTSIZE and SAVEHIST in [Parameters Used By The
|
||||
Shell](Parameters.html#Parameters-Used-By-The-Shell). Note that it’s
|
||||
currently only possible to read and write files saving history when the
|
||||
shell is interactive, i.e. it does not work from scripts.
|
||||
@ -73,19 +73,18 @@ The shell now supports the UTF-8 character set (and also others if
|
||||
supported by the operating system). This is (mostly) handled
|
||||
transparently by the shell, but the degree of support in terminal
|
||||
emulators is variable. There is some discussion of this in the shell
|
||||
FAQ, `http://www.zsh.org/FAQ/`. Note in particular that for combining
|
||||
characters to be handled the option `COMBINING_CHARS` needs to be set.
|
||||
FAQ, <https://www.zsh.org/FAQ/>. Note in particular that for combining
|
||||
characters to be handled the option COMBINING_CHARS needs to be set.
|
||||
Because the shell is now more sensitive to the definition of the
|
||||
character set, note that if you are upgrading from an older version of
|
||||
the shell you should ensure that the appropriate variable, either `LANG`
|
||||
(to affect all aspects of the shell’s operation) or `LC_CTYPE` (to
|
||||
affect only the handling of character sets) is set to an appropriate
|
||||
value. This is true even if you are using a single-byte character set
|
||||
including extensions of ASCII such as `ISO-8859-1` or `ISO-8859-15`. See
|
||||
the description of `LC_CTYPE` in
|
||||
[Parameters](Parameters.html#Parameters).
|
||||
the shell you should ensure that the appropriate variable, either LANG
|
||||
(to affect all aspects of the shell’s operation) or LC_CTYPE (to affect
|
||||
only the handling of character sets) is set to an appropriate value.
|
||||
This is true even if you are using a single-byte character set including
|
||||
extensions of ASCII such as ISO-8859-1 or ISO-8859-15. See the
|
||||
description of LC_CTYPE in [Parameters](Parameters.html#Parameters).
|
||||
|
||||
-----
|
||||
------------------------------------------------------------------------
|
||||
|
||||
<span id="Completion-1"></span>
|
||||
|
||||
@ -95,14 +94,14 @@ Completion is a feature present in many shells. It allows the user to
|
||||
type only a part (usually the prefix) of a word and have the shell fill
|
||||
in the rest. The completion system in zsh is programmable. For example,
|
||||
the shell can be set to complete email addresses in arguments to the
|
||||
mail command from your `~/.abook/addressbook`; usernames, hostnames, and
|
||||
mail command from your \~/.abook/addressbook; usernames, hostnames, and
|
||||
even remote paths in arguments to scp, and so on. Anything that can be
|
||||
written in or glued together with zsh can be the source of what the line
|
||||
editor offers as possible completions.
|
||||
|
||||
Zsh has two completion systems, an old, so called `compctl` completion
|
||||
Zsh has two completion systems, an old, so called compctl completion
|
||||
(named after the builtin command that serves as its complete and only
|
||||
user interface), and a new one, referred to as `compsys`, organized as
|
||||
user interface), and a new one, referred to as compsys, organized as
|
||||
library of builtin and user-defined functions. The two systems differ in
|
||||
their interface for specifying the completion behavior. The new system
|
||||
is more customizable and is supplied with completions for many commonly
|
||||
@ -112,7 +111,7 @@ The completion system must be enabled explicitly when the shell starts.
|
||||
For more information see [Completion
|
||||
System](Completion-System.html#Completion-System).
|
||||
|
||||
-----
|
||||
------------------------------------------------------------------------
|
||||
|
||||
<span id="Extending-the-line-editor"></span>
|
||||
|
||||
@ -122,29 +121,28 @@ Apart from completion, the line editor is highly extensible by means of
|
||||
shell functions. Some useful functions are provided with the shell; they
|
||||
provide facilities such as:
|
||||
|
||||
- `insert-composed-char`
|
||||
composing characters not found on the keyboard
|
||||
insert-composed-char
|
||||
composing characters not found on the keyboard
|
||||
|
||||
- `match-words-by-style`
|
||||
configuring what the line editor considers a word when moving or
|
||||
deleting by word
|
||||
match-words-by-style
|
||||
configuring what the line editor considers a word when moving or
|
||||
deleting by word
|
||||
|
||||
- `history-beginning-search-backward-end`, etc.
|
||||
alternative ways of searching the shell history
|
||||
history-beginning-search-backward-end, etc.
|
||||
alternative ways of searching the shell history
|
||||
|
||||
- `replace-string`, `replace-pattern`
|
||||
functions for replacing strings or patterns globally in the command
|
||||
line
|
||||
replace-string, replace-pattern
|
||||
functions for replacing strings or patterns globally in the command line
|
||||
|
||||
- `edit-command-line`
|
||||
edit the command line with an external editor.
|
||||
edit-command-line
|
||||
edit the command line with an external editor.
|
||||
|
||||
See [ZLE Functions](User-Contributions.html#ZLE-Functions) for
|
||||
descriptions of these.
|
||||
|
||||
-----
|
||||
------------------------------------------------------------------------
|
||||
|
||||
<span id="Options-3"></span>
|
||||
<span id="Options-1"></span>
|
||||
|
||||
## 3.3 Options
|
||||
|
||||
@ -153,7 +151,7 @@ These cover all aspects of the shell; browsing the full documentation is
|
||||
the only good way to become acquainted with the many possibilities. See
|
||||
[Options](Options.html#Options).
|
||||
|
||||
-----
|
||||
------------------------------------------------------------------------
|
||||
|
||||
<span id="Pattern-Matching"></span>
|
||||
|
||||
@ -168,22 +166,22 @@ Generation](Expansion.html#Filename-Generation).
|
||||
Of particular interest are the following patterns that are not commonly
|
||||
supported by other systems of pattern matching:
|
||||
|
||||
- `**`
|
||||
for matching over multiple directories
|
||||
\*\*
|
||||
for matching over multiple directories
|
||||
|
||||
- `|`
|
||||
for matching either of two alternatives
|
||||
\|
|
||||
for matching either of two alternatives
|
||||
|
||||
- `~`, `^`
|
||||
the ability to exclude patterns from matching when the
|
||||
`EXTENDED_GLOB` option is set
|
||||
\~, ^
|
||||
the ability to exclude patterns from matching when the EXTENDED_GLOB
|
||||
option is set
|
||||
|
||||
- `(``...``)`
|
||||
glob qualifiers, included in parentheses at the end of the pattern,
|
||||
which select files by type (such as directories) or attribute (such
|
||||
as size).
|
||||
(`...`)
|
||||
glob qualifiers, included in parentheses at the end of the pattern,
|
||||
which select files by type (such as directories) or attribute (such as
|
||||
size).
|
||||
|
||||
-----
|
||||
------------------------------------------------------------------------
|
||||
|
||||
<span id="General-Comments-on-Syntax"></span>
|
||||
|
||||
@ -197,13 +195,13 @@ Grammar](Shell-Grammar.html#Shell-Grammar).
|
||||
|
||||
One commonly encountered difference is that variables substituted onto
|
||||
the command line are not split into words. See the description of the
|
||||
shell option `SH_WORD_SPLIT` in [Parameter
|
||||
shell option SH_WORD_SPLIT in [Parameter
|
||||
Expansion](Expansion.html#Parameter-Expansion). In zsh, you can either
|
||||
explicitly request the splitting (e.g. `${=foo}`) or use an array when
|
||||
you want a variable to expand to more than one word. See [Array
|
||||
explicitly request the splitting (e.g. ${=foo}) or use an array when you
|
||||
want a variable to expand to more than one word. See [Array
|
||||
Parameters](Parameters.html#Array-Parameters).
|
||||
|
||||
-----
|
||||
------------------------------------------------------------------------
|
||||
|
||||
<span id="Programming"></span>
|
||||
|
||||
@ -221,25 +219,25 @@ above, are provided with the shell and are described in [User
|
||||
Contributions](User-Contributions.html#User-Contributions). Features
|
||||
include:
|
||||
|
||||
- `promptinit`
|
||||
a prompt theme system for changing prompts easily, see [Prompt
|
||||
Themes](User-Contributions.html#Prompt-Themes)
|
||||
promptinit
|
||||
a prompt theme system for changing prompts easily, see [Prompt
|
||||
Themes](User-Contributions.html#Prompt-Themes)
|
||||
|
||||
- `zsh-mime-setup`
|
||||
a MIME-handling system which dispatches commands according to the
|
||||
suffix of a file as done by graphical file managers
|
||||
zsh-mime-setup
|
||||
a MIME-handling system which dispatches commands according to the suffix
|
||||
of a file as done by graphical file managers
|
||||
|
||||
- `zcalc`
|
||||
a calculator
|
||||
zcalc
|
||||
a calculator
|
||||
|
||||
- `zargs`
|
||||
a version of `xargs` that makes the `find` command redundant
|
||||
zargs
|
||||
a version of xargs that makes the find command redundant
|
||||
|
||||
- `zmv`
|
||||
a command for renaming files by means of shell patterns.
|
||||
zmv
|
||||
a command for renaming files by means of shell patterns.
|
||||
|
||||
-----
|
||||
------------------------------------------------------------------------
|
||||
|
||||
This document was generated on *February 15, 2020* using
|
||||
[*texi2html 5.0*](http://www.nongnu.org/texi2html/).
|
||||
Zsh version 5.8, released on February 14, 2020.
|
||||
This document was generated on *May 14, 2022* using [*texi2html
|
||||
5.0*](http://www.nongnu.org/texi2html/).
|
||||
Zsh version 5.9, released on May 14, 2022.
|
||||
|
||||
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@ -7,15 +7,15 @@
|
||||
|
||||
<!-- END doctoc generated TOC please keep comment here to allow auto update -->
|
||||
|
||||
<span id="The-Z-Shell-Manual"></span>
|
||||
<span id="The-Z-Shell-Manual-1"></span>
|
||||
<span id="The-Z-Shell-Manual"></span> <span
|
||||
id="The-Z-Shell-Manual-1"></span>
|
||||
|
||||
# 1 The Z Shell Manual
|
||||
|
||||
This document has been produced from the texinfo file `zsh.texi`,
|
||||
included in the `Doc` sub-directory of the Zsh distribution.
|
||||
This document has been produced from the texinfo file zsh.texi, included
|
||||
in the Doc sub-directory of the Zsh distribution.
|
||||
|
||||
-----
|
||||
------------------------------------------------------------------------
|
||||
|
||||
<span id="Producing-documentation-from-zsh_002etexi"></span>
|
||||
|
||||
@ -23,34 +23,34 @@ included in the `Doc` sub-directory of the Zsh distribution.
|
||||
|
||||
The texinfo source may be converted into several formats:
|
||||
|
||||
- The Info manual
|
||||
The Info format allows searching for topics, commands, functions,
|
||||
etc. from the many Indices. The command ‘`makeinfo zsh.texi`’ is
|
||||
used to produce the Info documentation.
|
||||
The Info manual
|
||||
The Info format allows searching for topics, commands, functions, etc.
|
||||
from the many Indices. The command ‘makeinfo zsh.texi’ is used to
|
||||
produce the Info documentation.
|
||||
|
||||
- The printed manual
|
||||
The command ‘`texi2dvi zsh.texi`’ will output `zsh.dvi` which can
|
||||
then be processed with dvips and optionally gs (Ghostscript) to
|
||||
produce a nicely formatted printed manual.
|
||||
The printed manual
|
||||
The command ‘texi2dvi zsh.texi’ will output zsh.dvi which can then be
|
||||
processed with dvips and optionally gs (Ghostscript) to produce a nicely
|
||||
formatted printed manual.
|
||||
|
||||
- The HTML manual
|
||||
An HTML version of this manual is available at the Zsh web site via:
|
||||
The HTML manual
|
||||
An HTML version of this manual is available at the Zsh web site via:
|
||||
|
||||
`http://zsh.sourceforge.net/Doc/`.
|
||||
<https://zsh.sourceforge.io/Doc/>.
|
||||
|
||||
(The HTML version is produced with texi2html, which may be obtained
|
||||
from `http://www.nongnu.org/texi2html/`. The command is ‘`texi2html
|
||||
–output . –ifinfo –split=chapter –node-files zsh.texi`’. If
|
||||
necessary, upgrade to version 1.78 of texi2html.)
|
||||
(The HTML version is produced with texi2html, which may be obtained from
|
||||
<http://www.nongnu.org/texi2html/>. The command is ‘texi2html –output .
|
||||
–ifinfo –split=chapter –node-files zsh.texi’. If necessary, upgrade to
|
||||
version 1.78 of texi2html.)
|
||||
|
||||
For those who do not have the necessary tools to process texinfo,
|
||||
precompiled documentation (PostScript, dvi, PDF, info and HTML formats)
|
||||
is available from the zsh archive site or its mirrors, in the file
|
||||
`zsh-doc.tar.gz`. (See [Availability](Introduction.html#Availability)
|
||||
for a list of sites.)
|
||||
zsh-doc.tar.gz. (See [Availability](Introduction.html#Availability) for
|
||||
a list of sites.)
|
||||
|
||||
-----
|
||||
------------------------------------------------------------------------
|
||||
|
||||
This document was generated on *February 15, 2020* using
|
||||
[*texi2html 5.0*](http://www.nongnu.org/texi2html/).
|
||||
Zsh version 5.8, released on February 14, 2020.
|
||||
This document was generated on *May 14, 2022* using [*texi2html
|
||||
5.0*](http://www.nongnu.org/texi2html/).
|
||||
Zsh version 5.9, released on May 14, 2022.
|
||||
|
||||
File diff suppressed because it is too large
Load Diff
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Load Diff
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Load Diff
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Load Diff
@ -3,17 +3,17 @@
|
||||
**Table of Contents** *generated with [DocToc](https://github.com/thlorenz/doctoc)*
|
||||
|
||||
- [The Z Shell Manual](#the-z-shell-manual)
|
||||
- [Version 5.8](#version-58)
|
||||
- [Updated February 14, 2020](#updated-february-14-2020)
|
||||
- [Version 5.9](#version-59)
|
||||
- [Updated May 14, 2022](#updated-may-14-2022)
|
||||
- [The Z Shell Manual](#the-z-shell-manual-1)
|
||||
|
||||
<!-- END doctoc generated TOC please keep comment here to allow auto update -->
|
||||
|
||||
# The Z Shell Manual
|
||||
|
||||
### Version 5.8
|
||||
### Version 5.9
|
||||
|
||||
### Updated February 14, 2020
|
||||
### Updated May 14, 2022
|
||||
|
||||
**Original documentation by Paul Falstad**
|
||||
|
||||
@ -32,7 +32,7 @@ permission notice identical to this one.
|
||||
Permission is granted to copy and distribute translations of this manual
|
||||
into another language, under the above conditions for modified versions.
|
||||
|
||||
-----
|
||||
------------------------------------------------------------------------
|
||||
|
||||
<span id="Top"></span> <span id="The-Z-Shell-Manual-2"></span>
|
||||
|
||||
@ -46,7 +46,7 @@ compatible, either.
|
||||
|
||||
<span id="index-version"></span>
|
||||
|
||||
Version 5.8, last updated February 14, 2020.
|
||||
Version 5.9, last updated May 14, 2022.
|
||||
|
||||
— Indices —
|
||||
|
||||
@ -80,8 +80,8 @@ Zftp Function System
|
||||
|
||||
User Contributions
|
||||
|
||||
-----
|
||||
------------------------------------------------------------------------
|
||||
|
||||
This document was generated on *February 15, 2020* using
|
||||
[*texi2html 5.0*](http://www.nongnu.org/texi2html/).
|
||||
Zsh version 5.8, released on February 14, 2020.
|
||||
This document was generated on *May 14, 2022* using [*texi2html
|
||||
5.0*](http://www.nongnu.org/texi2html/).
|
||||
Zsh version 5.9, released on May 14, 2022.
|
||||
|
||||
Loading…
Reference in New Issue
Block a user