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CRONTAB(1)      DOMAIN/IX Reference Manual (SYS5)      CRONTAB(1)



NAME
     crontab - user crontab file

USAGE
     crontab [ -r ] [ -l ] [ file ]

DESCRIPTION
     Crontab copies the specified file (or the standard input if
     no file is named), into a directory that holds all users'
     crontab files.

     You can use crontab if your name appears in the file
     /usr/lib/cron/cron.allow. If that file does not exist, the
     file /usr/lib/cron/cron.deny determines whether or not you
     should be denied access to crontab. If neither file exists,
     only root can submit a job.  If either file is at.deny, glo-
     bal usage is permitted.  The allow/deny files consist of one
     user name per line.

     A crontab file consists of lines of six fields each.  The
     fields are separated by spaces or tabs.  The first five are
     integer patterns that specify the following information:

               minute (0-59),
               hour (0-23),
              day of the month (1-31),
              month of the year (1-12),
              day of the week (0-6 with 0=Sunday).

     Each of these patterns may be either an asterisk (*) to sig-
     nify all legal values, or a list of elements separated by
     commas.  An elements is either a number, or two numbers
     separated by a dash (-) to indicate an inclusive range.
     Note that you can specify days by using day of the month
     and/or day of the week.  If you use both fields as a list of
     elements, both are adhered to.  For example, 0 0 1,15 * 1
     runs a command on the first and fifteenth of each month, as
     well as on every Monday. To specify days by only one field,
     the other field should be set to an asterisk (*).  For exam-
     ple, 0 0 * * 1 runs a command only on Mondays.

     The sixth field of a line in a crontab file is a string that
     is executed by the Shell at the specified times.  A percent
     character (%) in this field, unless escaped by a backslash
     (\) is translated to a newline character.  Only the first
     line of the command field, up to a percent (%) or end of
     line, is executed by the Shell.  The other lines are made
     available to the command as standard input.

     The Shell is invoked from your $HOME directory with an arg0
     of sh (1).  If you desire to have your .profile executed,
     you must explicitly do so in the crontab file.  The cron



Printed 6/10/85                                         CRONTAB-1





CRONTAB(1)      DOMAIN/IX Reference Manual (SYS5)      CRONTAB(1)



     (1M) command supplies a default environment for every Shell,
     defining HOME, LOGNAME, SHELL (=/bin/sh), and PATH
     (=:/bin:/usr/bin:/usr/lbin).

CAUTIONS
     If you do not redirect standard output and standard error
     when using crontab, any generated output or errors are
     mailed to you.

     In some cases, your node may not have a resident /usr/lib
     directory.  Thus, when cron (1M) is run, it consults the
     crontab file that it shares with any other node that points
     off to /usr/lib.  You can avoid having to share the crontab
     file by making /usr/lib/crontab a link (softlink) as in the
     following three examples:

             `node_data/crontab

             /sys/cron/crontab

             ~/crontab

     Then when cron (1M) is run, it consults a local file that
     can be fashioned on a node- or user-basis.

FILES
     /usr/lib/cron            main cron directory

     /usr/spool/cron/crontabs spool area

     /usr/lib/cron/log        accounting information

     /usr/lib/cron/cron.allow list of allowed users

     /usr/lib/cron/cron.deny  list of denied users

RELATED INFORMATION
     sh (1), cron (1M).

















CRONTAB-2                                         Printed 6/10/85



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