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     CRON(8)                                                   CRON(8)

          cron - clock daemon


          Cron executes commands at specified dates and times accord-
          ing to the instructions in the file /usr/lib/crontab.  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/rc; see init(8).

          Crontab consists of lines of six fields each.  The fields
          are separated by spaces or tabs.  The first five are integer
          patterns to specify the minute (0-59), hour (0-23), day of
          the month (1-31), month of the year (1-12), and day of the
          week (1-7 with 1=monday).  Each of these patterns may con-
          tain a number in the range above; two numbers separated by a
          minus meaning a range inclusive; a list of numbers separated
          by commas meaning any of the numbers; or an asterisk meaning
          all legal values.  The sixth field is a string that is exe-
          cuted by the Shell at the specified times.  A percent char-
          acter in this field is translated to a new-line character.
          Only the first line (up to a % or end of line) of the com-
          mand field is executed by the Shell.  The other lines are
          made available to the command as standard input.

          Crontab is examined by cron every minute.