mirror of
https://github.com/fish-shell/fish-shell
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3a23fdf359
Includes harmonizing the display of options and arguments, standardising terminology, using the envvar directive more broadly, adding help options to all commands that support them, simplifying some language, and tidying up multiple formatting issues. string documentation is not changed.
54 lines
1.4 KiB
ReStructuredText
54 lines
1.4 KiB
ReStructuredText
.. _cmd-if:
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if - conditionally execute a command
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====================================
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Synopsis
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--------
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.. synopsis::
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if CONDITION; COMMANDS_TRUE ...;
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[else if CONDITION2; COMMANDS_TRUE2 ...;]
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[else; COMMANDS_FALSE ...;]
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end
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Description
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-----------
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``if`` will execute the command ``CONDITION``. If the condition's exit status is 0, the commands ``COMMANDS_TRUE`` will execute. If the exit status is not 0 and :ref:`else <cmd-else>` is given, ``COMMANDS_FALSE`` will be executed.
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You can use :ref:`and <cmd-and>` or :ref:`or <cmd-or>` in the condition. See the second example below.
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The exit status of the last foreground command to exit can always be accessed using the :ref:`$status <variables-status>` variable.
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The **-h** or **--help** option displays help about using this command.
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Example
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-------
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The following code will print ``foo.txt exists`` if the file foo.txt exists and is a regular file, otherwise it will print ``bar.txt exists`` if the file bar.txt exists and is a regular file, otherwise it will print ``foo.txt and bar.txt do not exist``.
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::
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if test -f foo.txt
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echo foo.txt exists
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else if test -f bar.txt
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echo bar.txt exists
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else
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echo foo.txt and bar.txt do not exist
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end
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The following code will print "foo.txt exists and is readable" if foo.txt is a regular file and readable
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::
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if test -f foo.txt
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and test -r foo.txt
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echo "foo.txt exists and is readable"
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end
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