crontab(1)                       DG/UX 5.4.2                      crontab(1)


NAME
       crontab - user crontab file

SYNOPSIS
       crontab [file]
       crontab -e [ username ]
       crontab -r [ username ]
       crontab -l [ username ]

DESCRIPTION
       crontab copies the specified file, or standard input if no file is
       specified, into a directory that holds all users' crontabs.  The -e
       option edits a copy of the current user's crontab file, or creates an
       empty file to edit if crontab does not exist.  When editing is
       complete, the file is installed as the user's crontab file.  If a
       username is given, the specified user's crontab file is edited,
       rather than the current user's crontab file; this may only be done by
       a privileged user.  The environment variable EDITOR determines which
       editor is invoked with the -e option.  The default editor is ed(1).
       One note of caution, if you plan to remove all of the entries from a
       crontab file, use the -r option described next.  The -r option
       removes a user's crontab from the crontab directory.  crontab -l will
       list the crontab file for the invoking user.  Only a privileged user
       can specify a username following the -r or -l options to remove or
       list the crontab file of the specified user.

       Users are permitted to use crontab if their names appear in the file
       /etc/cron.d/cron.allow.  If that file does not exist, the file
       /etc/cron.d/cron.deny is checked to determine if the user should be
       denied access to crontab.  If neither file exists, only root is
       allowed to submit a job.  If cron.allow does not exist and cron.deny
       exists but is empty, global 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:

            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  (meaning all legal
       values) or a list of elements separated by commas.  An element is
       either a number or two numbers separated by a minus sign (meaning an
       inclusive range).  Note that the specification of days may be made by
       two fields (day of the month and day of the week).  If both are
       specified as a list of elements, both are adhered to.  For example, 0
       0 1,15 * 1 would run 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 * (for example, 0 0 * * 1
       would run a command only on Mondays).



Licensed material--property of copyright holder(s)                         1

crontab(1)                       DG/UX 5.4.2                      crontab(1)


       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 \) is translated to a new-line
       character.  Only the first line (up to a % or end of line) of
       the command field is executed by the shell.  The other lines are made
       available to the command as standard input.

       Any line beginning with a # is a comment and will be ignored.

       The shell is invoked from your $HOME directory with an arg0 of sh.
       Users who desire to have their .profile executed must explicitly do
       so in the crontab file.  cron supplies a default environment for
       every shell, defining HOME, LOGNAME, SHELL (=/bin/sh), and PATH
       (=:/bin:/usr/bin:/usr/lbin).

       If you do not redirect the standard output and standard error of your
       commands, any generated output or errors will be mailed to you.

FILES
       /etc/cron.d              main cron directory
       /var/spool/cron/crontabs spool area
       /etc/cron.d/log          accounting information
       /etc/cron.d/cron.allow   list of allowed users
       /etc/cron.d/cron.deny    list of denied users

SEE ALSO
       atq(1), atrm(1), sh(1), su(1), ed(1).
       cron(1M).

NOTES
       If you inadvertently enter the crontab command with no argument(s),
       do not attempt to get out with a Ctrl-D.  This will cause all entries
       in your crontab file to be removed.  Instead, exit with a DEL.

       If a privileged user modifies another user's crontab file, resulting
       behavior may be unpredictable.  Instead, the privileged user should
       first su(1) to the other user's login before making any changes to
       the crontab file.



















Licensed material--property of copyright holder(s)                         2