File: coreutils.info,  Node: Exit status,  Next: Floating point,  Prev: Special built-in utilities,  Up: Common options

2.11 Exit status
================

Nearly every command invocation yields an integral “exit status” that
can be used to change how other commands work.  For the vast majority of
commands, an exit status of zero indicates success.  Failure is
indicated by a nonzero value – typically ‘1’, though it may differ on
unusual platforms as POSIX requires only that it be nonzero.

   However, some of the programs documented here do produce other exit
status values and a few associate different meanings with the values ‘0’
and ‘1’.  Here are the exceptions: ‘chroot’, ‘env’, ‘expr’, ‘ls’,
‘nice’, ‘nohup’, ‘numfmt’, ‘printenv’, ‘runcon’, ‘sort’, ‘stdbuf’,
‘test’, ‘timeout’, ‘tty’.