\section while while - perform a command multiple times \subsection while-synopsis Synopsis <tt>while CONDITION; COMMANDS; end</tt> \subsection while-synopsis Synopsis The <tt>while</tt> builtin causes fish to continually execute the command COMMANDS while the command CONDITION returns with status 0. \subsection while-example Example <tt>while test -f foo.txt; echo file exists; sleep 10; end</tt> causes fish to print the line 'file exists' at 10 second intervals as long as the file foo.txt exists.