\section while while - perform a command multiple times

\subsection while-synopsis Synopsis
\fish{synopsis}
while CONDITION; COMMANDS...; end
\endfish

\subsection while-description Description

`while` repeatedly executes `CONDITION`, and if the exit status is 0, then executes `COMMANDS`.

If the exit status of `CONDITION` is non-zero on the first iteration, `COMMANDS` will not be executed at all.

Use <a href="#begin">`begin; ...; end`</a> for complex conditions; more complex control can be achieved with `while true` containing a <a href="#break">break</a>.


\subsection while-example Example

\fish
while test -f foo.txt; echo file exists; sleep 10; end
# outputs 'file exists' at 10 second intervals as long as the file foo.txt exists.
\endfish