.\" $OpenBSD: shutdown.8,v 1.6 1997/07/25 14:27:46 kstailey Exp $ .\" $NetBSD: shutdown.8,v 1.6 1995/03/18 15:01:07 cgd Exp $ .\" .\" Copyright (c) 1988, 1991, 1993 .\" The Regents of the University of California. All rights reserved. .\" .\" Redistribution and use in source and binary forms, with or without .\" modification, are permitted provided that the following conditions .\" are met: .\" 1. Redistributions of source code must retain the above copyright .\" notice, this list of conditions and the following disclaimer. .\" 2. Redistributions in binary form must reproduce the above copyright .\" notice, this list of conditions and the following disclaimer in the .\" documentation and/or other materials provided with the distribution. .\" 3. All advertising materials mentioning features or use of this software .\" must display the following acknowledgement: .\" This product includes software developed by the University of .\" California, Berkeley and its contributors. .\" 4. Neither the name of the University nor the names of its contributors .\" may be used to endorse or promote products derived from this software .\" without specific prior written permission. .\" .\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND .\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE .\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE .\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL .\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS .\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) .\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT .\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF .\" SUCH DAMAGE. .\" .\" @(#)shutdown.8 8.1 (Berkeley) 6/5/93 .\" .Dd June 5, 1993 .Dt SHUTDOWN 8 .Os BSD 4 .Sh NAME .Nm shutdown .Nd "close down the system at a given time" .Sh SYNOPSIS .Nm shutdown .Op Fl .Op Fl dfhkrnp .Ar time .Op Ar warning-message ... .Sh DESCRIPTION .Nm Shutdown provides an automated shutdown procedure for super-users to nicely notify users when the system is shutting down, saving them from system administrators, hackers, and gurus, who would otherwise not bother with such niceties. .Pp Available friendlinesses: .Bl -tag -width time .It Fl d The system will perform a crash dump. .It Fl f .Nm Shutdown arranges, in the manner of .Xr fastboot 8 , for the file systems .Em not to be checked on reboot. .It Fl h The system is halted at the specified .Ar time when .Nm shutdown execs .Xr halt 8 . .It Fl k Kick every body off. The .Fl k option does not actually halt the system, but leaves the system multi-user with logins disabled (for all but super-user). .It Fl n Prevent the normal .Xr sync 2 before stopping. .It Fl r .Nm Shutdown execs .Xr reboot 8 at the specified .Ar time . .It Fl p The .Fl p flag is passed on to .Xr halt 8 , causing machines which support automatic power down to do so after halting. .It Ar time .Ar Time is the time at which .Nm shutdown will bring the system down and may be the word .Ar now (indicating an immediate shutdown) or specify a future time in one of two formats: .Ar +number , or .Ar yymmddhhmm , where the year, month, and day may be defaulted to the current system values. The first form brings the system down in .Ar number minutes and the second at the absolute time specified. .It Ar warning-message Any other arguments comprise the warning message that is broadcast to users currently logged into the system. .It Fl If .Ql Fl is supplied as an option, the warning message is read from the standard input. .El .Pp At intervals, becoming more frequent as apocalypse approaches and starting at ten hours before shutdown, warning messages are displayed on the terminals of all users logged in. Five minutes before shutdown, or immediately if shutdown is in less than 5 minutes, logins are disabled by creating .Pa /etc/nologin and copying the warning message there. If this file exists when a user attempts to log in, .Xr login 1 prints its contents and exits. The file is removed just before .Nm shutdown exits. .Pp At shutdown time a message is written in the system log, containing the time of shutdown, who initiated the shutdown and the reason. A terminate signal is then sent to .Xr init to bring the system down to single-user state (depending on above options). The time of the shutdown and the warning message are placed in .Pa /etc/nologin and should be used to inform the users about when the system will be back up and why it is going down (or anything else). .Sh FILES .Bl -tag -width /etc/nologin -compact .It Pa /etc/nologin tells login not to let anyone log in .It Pa /fastboot tells .Xr rc 8 not to run fsck when rebooting .El .Sh SEE ALSO .Xr login 1 , .Xr wall 1 , .Xr fastboot 8 , .Xr halt 8 , .Xr reboot 8 .Sh BACKWARD COMPATIBILITY The hours and minutes in the second time format may be separated by a colon (``:'') for backward compatibility. .Sh HISTORY The .Nm command appeared in .Bx 4.0 .