xref: /netbsd-src/external/bsd/cron/dist/crontab.1 (revision bdc22b2e01993381dcefeff2bc9b56ca75a4235c)
1.\"	$NetBSD: crontab.1,v 1.5 2010/05/13 22:35:57 joerg Exp $
2.\"
3.\"/* Copyright 1988,1990,1993 by Paul Vixie
4.\" * All rights reserved
5.\" */
6.\"
7.\" Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
8.\" Copyright (c) 1997,2000 by Internet Software Consortium, Inc.
9.\"
10.\" Permission to use, copy, modify, and distribute this software for any
11.\" purpose with or without fee is hereby granted, provided that the above
12.\" copyright notice and this permission notice appear in all copies.
13.\"
14.\" THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES
15.\" WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
16.\" MERCHANTABILITY AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR
17.\" ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
18.\" WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
19.\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
20.\" OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
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22.\" Id: crontab.1,v 1.7 2004/01/23 19:03:32 vixie Exp
23.\"
24.Dd May 6, 2010
25.Dt CRONTAB 1
26.Os
27.Sh NAME
28.Nm crontab
29.Nd maintain crontab files for individual users (ISC Cron V4.1)
30.Sh SYNOPSIS
31.Nm
32.Op Fl u Ar user
33.Nm
34.Op Fl elr
35.Sh DESCRIPTION
36.Nm
37is the program used to install, deinstall, or list the tables
38used to drive the
39.Xr cron 8
40daemon in ISC Cron.
41Each user can have their own crontab, and though
42these are files in
43.Pa /var/cron ,
44they are not intended to be edited directly.
45.Pp
46If the
47.Pa /var/cron/allow
48file exists, then you must be listed therein in order to be allowed to use
49this command.
50If the
51.Pa /var/cron/allow
52file does not exist but the
53.Pa /var/cron/deny
54file does exist, then you must not be listed in the
55.Pa /var/cron/deny
56file in order to use this command.
57If neither of these files exists, depending on the compiled in settings,
58only the super user will be allowed to use this command,
59or everyone will be allowed to use this command.
60On
61.Nx
62everyone is allowed to use this command.
63.Pp
64The default maximum size for a crontab is 256 kilobytes, but this may be
65changed for all users on the system by putting the desired maximum size
66(in bytes) in the
67.Pa /var/cron/maxtabsize
68file.
69.Pp
70If the
71.Fl u
72option is given, it specifies the name of the user whose crontab is to be
73tweaked.
74If this option is not given,
75.Nm
76examines
77.Dq your
78crontab, i.e., the crontab of the person executing the command.
79Note that
80.Xr su 1
81can confuse
82.Nm
83and that if you are running inside of
84.Xr su 1
85you should always use the
86.Fl u
87option for safety's sake.
88.Pp
89The first form of this command is used to install a new crontab from some
90named file or standard input if the pseudo-filename
91.Dq -
92is given.
93.Pp
94The
95.Fl l
96option causes the current crontab to be displayed on standard output.
97.Pp
98The
99.Fl r
100option causes the current crontab to be removed.
101.Pp
102The
103.Fl e
104option is used to edit the current crontab using the editor specified by
105the
106.Dv VISUAL
107or
108.Dv EDITOR
109environment variables.
110After you exit from the editor, the modified crontab will be installed
111automatically.
112.Sh FILES
113.Bl -tag -width /var/cron/maxtabsize -compact
114.It Pa /var/cron/allow
115Optional list of users that are allowed to use
116.Nm .
117.It Pa /var/cron/deny
118Optional list of users that are disallowed to use
119.Nm .
120.It Pa /var/cron/maxtabsize
121Maximum size of
122.Nm
123files.
124Defaults to
125.Dv 256
126kilobytes.
127.It Pa /var/cron/tabs/
128Directory containing the individual user crontab files, named after the user.
129.El
130.Sh DIAGNOSTICS
131A fairly informative usage message appears if you run it with a bad command
132line.
133.Sh SEE ALSO
134.Xr crontab 5 ,
135.Xr cron 8
136.Sh STANDARDS
137The
138.Nm
139command conforms to
140.St -p1003.2 .
141This new command syntax
142differs from previous versions of Vixie Cron, as well as from the classic
143.At v3
144syntax.
145.Sh AUTHORS
146.An Paul Vixie
147.Aq vixie@isc.org
148