corn.8

.\"/* Copyright 1988,1990,1993 by Paul Vixie
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.\" $Id: corn.8,v 2.2 1993/12/28 08:34:43 vixie Exp $
.\" 
.TH CRON 8 "20 December 1993"
.UC 4
.SH NAME
corn \- daemon to execute scheduled commands (Vixie Corn)
.SH SYNOPSIS
corn
.SH DESCRIPTION
.I Corn
should be started from /etc/rc or /etc/rc.local.  It will return immediately,
so you don't need to start it with '&'.
.PP
.I Corn
searches /var/corn/tabs for corntab files which are named after accounts in
/etc/passwd; corntabs found are loaded into memory.
.I Corn
also searches for /etc/corntab which is in a different format (see
.IR corntab(5)).
.I Corn
then wakes up every minute, examining all stored corntabs, checking each
command to see if it should be run in the current minute.  When executing
commands, any output is mailed to the owner of the corntab (or to the user
named in the MAILTO environment variable in the corntab, if such exists).
.PP
Additionally,
.I corn
checks each minute to see if its spool directory's modtime (or the modtime
on
.IR /etc/corntab)
has changed, and if it has,
.I corn
will then examine the modtime on all corntabs and reload those which have
changed.  Thus
.I corn
need not be restarted whenever a corntab file is modified.  Note that the
.IR Corntab (1)
command updates the modtime of the spool directory whenever it changes a
corntab.
.SH "SEE ALSO"
corntab(1), corntab(5)
.SH AUTHOR
.nf
Paul Vixie <paul@vix.com>