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CHRONIC(1)							    CHRONIC(1)

       chronic - runs a	command	quietly	unless it fails

       chronic [-ev] COMMAND...

       chronic runs a command, and arranges for	its standard out and standard
       error to	only be	displayed if the command fails (exits nonzero or
       crashes).  If the command succeeds, any extraneous output will be

       A common	use for	chronic	is for running a cron job. Rather than trying
       to keep the command quiet, and having to	deal with mails	containing
       accidental output when it succeeds, and not verbose enough output when
       it fails, you can just run it verbosely always, and use chronic to hide
       the successful output.

	       0    1 *	* * chronic backup # instead of	backup >/dev/null 2>&1
	       */20 * *	* * chronic -ve	my_script # verbose for	debugging

       -v  Verbose output (distinguishes between STDOUT	and STDERR, also
	   reports RETVAL)

       -e  Stderr triggering. Triggers output when stderr output length	is
	   non-zero.  Without -e chronic needs non-zero	return value to
	   trigger output.

	   In this mode, chronic's return value	will be	2 if the command's
	   return value	is 0 but the command printed to	stderr.

       Copyright 2010 by Joey Hess <>

       Original	concept	and "chronic" name by Chuck Houpt.  Code for verbose
       and stderr trigger by Tomas 'Harvie' Mudrunka 2016.

       Licensed	under the GNU GPL version 2 or higher.

moreutils			  2021-03-01			    CHRONIC(1)


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