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CRONTAB(1)                  General Commands Manual                 CRONTAB(1)

NAME
     crontab - maintain crontab files for individual users (ISC Cron V4.1)

SYNOPSIS
     crontab [-u user]
     crontab [-elr]

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

     If the /var/cron/allow file exists, then you must be listed therein in
     order to be allowed to use this command.  If the /var/cron/allow file
     does not exist but the /var/cron/deny file does exist, then you must not
     be listed in the /var/cron/deny file in order to use this command.  If
     neither of these files exists, depending on the compiled in settings,
     only the super user will be allowed to use this command, or everyone will
     be allowed to use this command.  On NetBSD everyone is allowed to use
     this command.

     The default maximum size for a crontab is 256 kilobytes, but this may be
     changed for all users on the system by putting the desired maximum size
     (in bytes) in the /var/cron/maxtabsize file.

     If the -u option is given, it specifies the name of the user whose
     crontab is to be tweaked.  If this option is not given, crontab examines
     "your" crontab, i.e., the crontab of the person executing the command.
     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.

     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.

     The -l option causes the current crontab to be displayed on standard
     output.

     The -r option causes the current crontab to be removed.

     The -e option is used to edit the current crontab using the editor
     specified by the VISUAL or EDITOR environment variables.  After you exit
     from the editor, the modified crontab will be installed automatically.

FILES
     /var/cron/allow       Optional list of users that are allowed to use
                           crontab.
     /var/cron/deny        Optional list of users that are disallowed to use
                           crontab.
     /var/cron/maxtabsize  Maximum size of crontab files.  Defaults to 256
                           kilobytes.
     /var/cron/tabs/       Directory containing the individual user crontab
                           files, named after the user.

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

SEE ALSO
     crontab(5), cron(8)

STANDARDS
     The crontab command conforms to IEEE Std 1003.2 ("POSIX.2").  This new
     command syntax differs from previous versions of Vixie Cron, as well as
     from the classic Version 3 AT&T UNIX syntax.

AUTHORS
     Paul Vixie <vixie@isc.org>

NetBSD 10.99                      May 6, 2010                     NetBSD 10.99