1 .\" Copyright (c) 1988, 1991, 1993
2 .\" The Regents of the University of California. All rights reserved.
4 .\" Redistribution and use in source and binary forms, with or without
5 .\" modification, are permitted provided that the following conditions
7 .\" 1. Redistributions of source code must retain the above copyright
8 .\" notice, this list of conditions and the following disclaimer.
9 .\" 2. Redistributions in binary form must reproduce the above copyright
10 .\" notice, this list of conditions and the following disclaimer in the
11 .\" documentation and/or other materials provided with the distribution.
12 .\" 3. All advertising materials mentioning features or use of this software
13 .\" must display the following acknowledgement:
14 .\" This product includes software developed by the University of
15 .\" California, Berkeley and its contributors.
16 .\" 4. Neither the name of the University nor the names of its contributors
17 .\" may be used to endorse or promote products derived from this software
18 .\" without specific prior written permission.
20 .\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21 .\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 .\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24 .\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 .\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 .\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 .\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 .\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 .\" @(#)shutdown.8 8.2 (Berkeley) 4/27/95
33 .\" $FreeBSD: src/sbin/shutdown/shutdown.8,v 1.12.2.5 2003/02/23 21:17:43 trhodes Exp $
34 .\" $DragonFly: src/sbin/shutdown/shutdown.8,v 1.3 2006/02/17 19:33:33 swildner Exp $
41 .Nd "close down the system at a given time"
54 .Op Ar warning-message ...
58 utility provides an automated shutdown procedure for super-users
59 to nicely notify users when the system is shutting down,
60 saving them from system administrators, hackers, and gurus, who
61 would otherwise not bother with such niceties.
63 The following options are available:
64 .Bl -tag -width indent
66 The system is halted at the specified
69 The system is halted and the power is turned off
70 (hardware support required)
74 The system is rebooted at the specified
81 does not actually halt the system, but leaves the
82 system multi-user with logins disabled (for all but super-user).
95 instead of sending signal to
100 is specified, prevent the file system cache from being flushed by passing
106 This option should probably not be used.
111 will bring the system down and
114 (indicating an immediate shutdown) or
115 specify a future time in one of two formats:
119 where the year, month, and day may be defaulted
120 to the current system values. The first form brings the system down in
122 minutes and the second at the absolute time specified.
123 .It Ar warning-message
124 Any other arguments comprise the warning message that is broadcast
125 to users currently logged into the system.
129 is supplied as an option, the warning message is read from the standard
133 At intervals, becoming more frequent as apocalypse approaches
134 and starting at ten hours before shutdown, warning messages are displayed
135 on the terminals of all users logged in. Five minutes before
136 shutdown, or immediately if shutdown is in less than 5 minutes,
137 logins are disabled by creating
140 warning message there. If this file exists when a user attempts to
143 prints its contents and exits. The file is
148 At shutdown time a message is written to the system log, containing the
149 time of shutdown, the person who initiated the shutdown and the reason.
150 Corresponding signal is then sent to
152 to respectively halt, reboot or bring the system down to single-user state
153 (depending on the above options).
154 The time of the shutdown and the warning message
157 and should be used to
158 inform the users about when the system will be back up
159 and why it is going down (or anything else).
161 A scheduled shutdown can be canceled by killing the
170 created will be removed automatically.
172 .Bl -tag -width /var/run/nologin -compact
173 .It Pa /var/run/nologin
174 tells login not to let anyone log in
176 .Sh BACKWARD COMPATIBILITY
177 The hours and minutes in the second time format may be separated by
178 a colon (``:'') for backward compatibility.