2.11BSD#431 - /usr/man/cat8/cron.0

CRON(8)             UNIX Programmer's Manual              CRON(8)


NAME
     cron - daemon to execute scheduled commands (Vixie Cron)

SYNOPSIS
     cron

DESCRIPTION
     Cron should be started from /etc/rc or /etc/rc.local.  It
     will return immediately, so you don't need to start it with
     '&'.

     Cron searches /var/cron/tabs for crontab files which are
     named after accounts in /etc/passwd; crontabs found are
     loaded into memory.  Cron also searches for /etc/crontab
     which is in a different format (see crontab(5)).  Cron then
     wakes up every minute, examining all stored crontabs, check-
     ing 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 crontab (or to the user named in the MAILTO
     environment variable in the crontab, if such exists).

     Additionally, cron checks each minute to see if its spool
     directory's modtime (or the modtime on /etc/crontab) has
     changed, and if it has, cron will then examine the modtime
     on all crontabs and reload those which have changed.  Thus
     cron need not be restarted whenever a crontab file is modi-
     fied.  Note that the Crontab(1) command updates the modtime
     of the spool directory whenever it changes a crontab.

SEE ALSO
     crontab(1), crontab(5)

AUTHOR
     Paul Vixie <paul@vix.com>


Printed 11/26/99        20 December 1993                        1