crontab -- maintain crontab files for individual users (V3)
crontab [-u user] file
crontab [-u user] { -l | -r | -e }
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 though these are files in /var, they are not
intended to be edited directly.
If the allow file exists, then you must be listed therein in order to be
allowed to use this command. If the allow file does not exist but the
deny file does exist, then you must not be listed in the deny file in
order to use this command. If neither of these files exists, then
depending on site-dependent configuration 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.
crontab(5), cron(8)
/var/cron/allow
/var/cron/deny
The crontab command conforms to IEEE Std 1003.2 (``POSIX.2'') with the
exception that the dangerous variant of calling crontab without a file
name in the first form of the command is not allowed by this implementation.
The pseudo-filename ``-'' must be specified to read from standard
input. The new command syntax differs from previous versions of Vixie
Cron, as well as from the classic SVR3 syntax.
A fairly informative usage message appears if you run it with a bad command
line.
Paul Vixie <[email protected]>
FreeBSD 5.2.1 December 29, 1993 FreeBSD 5.2.1 [ Back ] |