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02d82dcf85
Adds synopses for those commands missing them. Moves all synopsis sections to code blocks. This improves the appearance, although highlighting as fish code may not be the ideal appearance.
53 lines
1.3 KiB
ReStructuredText
53 lines
1.3 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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::
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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 ``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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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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