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crontab(1)

crontab(5)



CRON(8)                        1993                       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,
       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 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
       modified.   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>





















December                        20                              1


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