CRONTAB(1)                 OpenBSD Reference Manual                 CRONTAB(1)

NAME
     crontab - maintain crontab files for individual users

SYNOPSIS
     crontab [-u user] file
     crontab [-e | -l | -r] [-u user]

DESCRIPTION
     crontab is the program used to install, deinstall, or list the tables
     used to drive the cron(8) daemon.  Each user can have their own
     crontab(5), and though these are files in /var/cron/tabs, they are not
     intended to be edited directly.

     The first form of this command is used to install a new crontab from some
     named file, or standard input if the pseudo-filename `-' is given.

     If the /var/cron/cron.allow file exists, then you must be listed therein
     in order to use crontab.  If the /var/cron/cron.allow file does not exist
     but the /var/cron/cron.deny file does exist, then you must not be listed
     in the /var/cron/cron.deny file in order to use crontab.  If neither of
     these files exists then only the super user will be allowed to use
     crontab.  NOTE: if they exist, /var/cron/cron.allow and
     /var/cron/cron.deny must be readable by group crontab.  If crontab is un-
     able to read the files, users will not be allowed to use crontab.

     The options are as follows:

     -e        Edit the current crontab using the editor specified by the
               VISUAL or EDITOR environment variables.  After you exit from
               the editor, the modified crontab(5) will be installed automati-
               cally.

     -l        Causes the current crontab to be displayed on standard output.

     -r        Causes the current crontab to be removed.

     -u user   Specifies the name of the user whose crontab(5) is to be edit-
               ed.  If this option is not given, crontab examines ``your''
               crontab(5); i.e., the crontab of the person executing the com-
               mand.  Note that su(1) can confuse crontab and that if you are
               running inside of su(1) you should always use the -u option for
               safety's sake.

FILES
     /var/cron/cron.allow  list of users allowed to use crontab
     /var/cron/cron.deny   list of users prohibited from using crontab
     /var/cron/tabs        directory of individual crontabs

DIAGNOSTICS
     A fairly informative usage message appears if you run it with a bad com-
     mand line.

SEE ALSO
     at(1), crontab(5), cron(8)

STANDARDS
     The crontab utility is compliant with the IEEE Std 1003.1-2008
     (``POSIX'') specification.

     The flag [-u] is an extension to that specification.

AUTHORS
     Paul Vixie <vixie@isc.org>

OpenBSD 4.7                    February 8, 2009                              1
