fish-shell/sphinx_doc_src/cmds/while.rst
David Adam 02d82dcf85 docs: update all command synopsis formatting
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.
2019-09-17 17:59:04 +08:00

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ReStructuredText

.. _cmd-while:
while - perform a command multiple times
========================================
Synopsis
--------
::
while CONDITION; COMMANDS...; end
Description
-----------
``while`` repeatedly executes ``CONDITION``, and if the exit status is 0, then executes ``COMMANDS``.
The exit status of the while loop is the exit status of the last iteration of the ``COMMANDS`` executed, or 0 if none were executed. (This matches other shells and is POSIX-compatible.)
You can use :ref:`and <cmd-and>` or :ref:`or <cmd-or>` for complex conditions. Even more complex control can be achieved with ``while true`` containing a :ref:`break <cmd-break>`.
Example
-------
::
while test -f foo.txt; or test -f bar.txt ; echo file exists; sleep 10; end
# outputs 'file exists' at 10 second intervals as long as the file foo.txt or bar.txt exists.