cron(1M)                                                           cron(1M)


   NAME
         cron - clock daemon

   SYNOPSIS
         /usr/sbin/cron

   DESCRIPTION
         The cron command starts a process that executes commands at specified
         dates and times.  Regularly scheduled commands can be specified
         according to instructions found in crontab files in the directory
         /var/spool/cron/crontabs.  Users can submit their own crontab file
         via the crontab command.  Commands which are to be executed only once
         may be submitted via the at command.

         cron only examines crontab files and at command files during process
         initialization and when a file changes via the crontab or at
         commands.  This reduces the overhead of checking for new or changed
         files at regularly scheduled intervals.

         Since cron never exits, it should be executed only once.  This is
         done routinely through /etc/rc2.d/S75cron at system boot time.
         /etc/cron.d/FIFO is used as a lock file to prevent the execution of
         more than one cron.

         To keep a log of all actions taken by cron, CRONLOG=YES (by default)
         must be specified in the /etc/default/cron file.  If CRONLOG=NO is
         specified, no logging is done.  Keeping the log is a user
         configurable option since cron usually creates huge log files.

   FILES
        /etc/cron.d      main cron directory

        /etc/default/cron
                          used to maintain a log

        /etc/cron.d/FIFO used as a lock file

        /etc/cron.d/log  accounting information

        /var/spool/cron  spool area

   SEE ALSO
         at(1), crontab(1), sh(1) in the User's Reference Manual.

   DIAGNOSTICS
         A history of all actions taken by cron are recorded in
         /etc/cron.d/log.






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