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



NAME
     cron - clock daemon

SYNOPSIS
     /usr/sbin/cron

DESCRIPTION
     Cron executes commands at specified dates and times accord-
     ing to the instructions in the file /etc/crontab (if it exists).
     Since cron never exits, it should only be executed once.  This
     is best done by running cron from the initialization process
     through the file /etc/inittab; see init(8).

     The crontab file consists of lines of seven fields each.
     The fields are separated by spaces or tabs.  The first five
     are integer patterns to specify:

     o+ minute (0-59)
     o+ hour (0-23)
     o+ day of the month (1-31)
     o+ month of the year (1-12)
     o+ day of the week (1-7 with 1 = Monday)

     Each of these patterns may contain:

     o+ a number in the range above
     o+ two numbers separated by a minus meaning a range inclusive
     o+ a list of numbers separated by commas meaning any of the
       numbers
     o+ an asterisk meaning all legal values

     The sixth field is a user name: the command will be run with
     that user's uid and permissions.  The seventh field consists
     of all the text on a line following the sixth field, includ-
     ing spaces and tabs; this text is treated as a command which
     is executed by the Shell at the specified times.  A percent
     character (``%'') in this field is translated to a new-line
     character.

     The crontab file is checked by cron every minute, on the
     minute.

FILES
     /etc/crontab
