crontab.1

source code of crond

.\"/* Copyright 1988,1990,1993 by Paul Vixie
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.\" * anyone resulting from the use of this software rests entirely with the
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.\"
.\" $Id: crontab.1,v 2.4 1993/12/31 10:47:33 vixie Exp $
.\"
.TH CRONTAB 1 "29 December 1993"
.UC 4
.SH NAME
crontab \- maintain crontab files for individual users (V3)
.SH SYNOPSIS
crontab [ -u user ] file
.br
crontab [ -u user ] { -l | -r | -e }
.SH DESCRIPTION
.I Crontab
is the program used to install, deinstall or list the tables
used to drive the
.IR 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.
.PP
If the
.I allow
file exists, then you must be listed therein in order to be allowed to use
this command.  If the
.I allow
file does not exist but the
.I deny
file does exist, then you must \fBnot\fR be listed in the
.I 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.
.PP
If the
.I -u
option is given, it specifies the name of the user whose crontab is to be
tweaked.  If this option is not given,
.I crontab
examines "your" crontab, i.e., the crontab of the person executing the
command.  Note that
.IR su (8)
can confuse
.I crontab
and that if you are running inside of
.IR su (8)
you should always use the
.I -u
option for safety's sake.
.PP
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.
.PP
The
.I -l
option causes the current crontab to be displayed on standard output.
.PP
The
.I -r
option causes the current crontab to be removed.
.PP
The
.I -e
option is used to edit the current crontab using the editor specified by
the \s-1VISUAL\s+1 or \s-1EDITOR\s+1 environment variables.  After you exit
from the editor, the modified crontab will be installed automatically.
.SH "SEE ALSO"
crontab(5), cron(8)
.SH FILES
.nf
/var/cron/allow
/var/cron/deny
.fi
.SH STANDARDS
The
.I crontab
command conforms to IEEE Std1003.2-1992 (``POSIX'').  This new command syntax
differs from previous versions of Vixie Cron, as well as from the classic
SVR3 syntax.
.SH DIAGNOSTICS
A fairly informative usage message appears if you run it with a bad command
line.
.SH AUTHOR
.nf
Paul Vixie <[e-mail]>