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crontab(1)                BSD General Commands Manual               crontab(1)


NAME

     crontab -- maintain crontab files for individual users (V3)


SYNOPSIS

     crontab [-u user] file
     crontab [-u user] { -l | -r | -e }


DESCRIPTION

     The crontab utility is the program used to install, deinstall or list the
     tables used to drive the cron(8) daemon in Vixie Cron.  Each user can
     have their own crontab, and they are not intended to be edited directly.

     (Darwin note: Although cron(8) and crontab(5) are officially supported
     under Darwin, their functionality has been absorbed into launchd(8),
     which provides a more flexible way of automatically executing commands.
     See launchctl(1) for more information.)

     If the /usr/lib/cron/cron.allow file exists, then you must be listed
     therein in order to be allowed to use this command.  If the
     /usr/lib/cron/cron.allow file does not exist but the
     /usr/lib/cron/cron.deny file does exist, then you must not be listed in
     the /usr/lib/cron/cron.deny file in order to use this command.  If nei-
     ther of these files exists, then depending on site-dependent configura-
     tion parameters, only the super user will be allowed to use this command,
     or all users will be able to use this command.  The format of these files
     is one username per line, with no leading or trailing whitespace.  Lines
     of other formats will be ignored, and so can be used for comments.

     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 following options are available:

     -u      Specify 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.

     -l      Display the current crontab on standard output.

     -r      Remove the current crontab.

     -e      Edit the current crontab using the editor specified by the VISUAL
             or EDITOR environment variables.  The specified editor must edit
             the file in place; any editor that unlinks the file and recreates
             it cannot be used.  After you exit from the editor, the modified
             crontab will be installed automatically.


FILES

     /usr/lib/cron/cron.allow
     /usr/lib/cron/cron.deny


DIAGNOSTICS

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


SEE ALSO

     crontab(5), compat(5), cron(8), launchctl(1)


STANDARDS

     The crontab command conforms to IEEE Std 1003.2 (``POSIX.2'').  The new
     command syntax differs from previous versions of Vixie Cron, as well as
     from the classic SVR3 syntax.


AUTHORS

     Paul Vixie <paul@vix.com>

BSD                            December 29, 1993                           BSD

Mac OS X 10.6 - Generated Thu Sep 17 20:07:23 CDT 2009