1.\" Copyright (c) 1988, 1991 The Regents of the University of California. 2.\" All rights reserved. 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 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. 19.\" 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 30.\" SUCH DAMAGE. 31.\" 32.\" @(#)shutdown.8 6.8 (Berkeley) 3/16/91 33.\" 34.\" $Header: /cvsroot/src/sbin/shutdown/shutdown.8,v 1.3 1993/03/23 00:31:10 cgd Exp $ 35.\" 36.Dd March 16, 1991 37.Dt SHUTDOWN 8 38.Os BSD 4 39.Sh NAME 40.Nm shutdown 41.Nd "close down the system at a given time" 42.Sh SYNOPSIS 43.Nm shutdown 44.Op Fl 45.Op Fl fhkrn 46.Ar time 47.Op Ar warning-message ... 48.Sh DESCRIPTION 49.Nm Shutdown 50provides an automated shutdown procedure for super-users 51to nicely notify users when the system is shutting down, 52saving them from system administrators, hackers, and gurus, who 53would otherwise not bother with such niceties. 54.Pp 55Available friendlinesses: 56.Bl -tag -width time 57.It Fl f 58.Nm Shutdown 59arranges, in the manner of 60.Xr fastboot 8 , 61for the file systems 62.Em not to be 63checked on reboot. 64.It Fl h 65The system is halted at the specified 66.Ar time 67when 68.Nm shutdown 69execs 70.Xr halt 8 . 71.It Fl k 72Kick every body off. 73The 74.Fl k 75option 76does not actually halt the system, but leaves the 77system multi-user with logins disabled (for all but super-user). 78.It Fl n 79Prevent the normal 80.Xr sync 2 81before stopping. 82.It Fl r 83.Nm Shutdown 84execs 85.Xr reboot 8 86at the specified 87.Ar time . 88.It Ar time 89.Ar Time 90is the time at which 91.Nm shutdown 92will bring the system down and 93may be the word 94.Ar now 95(indicating an immediate shutdown) or 96specify a future time in one of two formats: 97.Ar +number , 98or 99.Ar yymmddhhmm , 100where the year, month, and day may be defaulted 101to the current system values. The first form brings the system down in 102.Ar number 103minutes and the second at the absolute time specified. 104.It Ar warning-message 105Any other arguments comprise the warning message that is broadcast 106to users currently logged into the system. 107.It Fl 108If 109.Ql Fl 110is supplied as an option, the warning message is read from the standard 111input. 112.El 113.Pp 114At intervals, becoming more frequent as apocalypse approaches 115and starting at ten hours before shutdown, warning messages are displayed 116on the terminals of all users logged in. Five minutes before 117shutdown, or immediately if shutdown is in less than 5 minutes, 118logins are disabled by creating 119.Pa /etc/nologin 120and copying the 121warning message there. If this file exists when a user attempts to 122log in, 123.Xr login 1 124prints its contents and exits. The file is 125removed just before 126.Nm shutdown 127exits. 128.Pp 129At shutdown time a message is written in the system log, containing the 130time of shutdown, who initiated the shutdown and the reason. 131A terminate 132signal is then sent to 133.Xr init 134to bring the system down to single-user state (depending on above 135options). 136The time of the shutdown and the warning message 137are placed in 138.Pa /etc/nologin 139and should be used to 140inform the users about when the system will be back up 141and why it is going down (or anything else). 142.Sh FILES 143.Bl -tag -width /etc/nologin -compact 144.It Pa /etc/nologin 145tells login not to let anyone log in 146.It Pa /fastboot 147tells 148.Xr rc 8 149not to run fsck when rebooting 150.El 151.Sh SEE ALSO 152.Xr login 1 , 153.Xr wall 1 , 154.Xr fastboot 8 , 155.Xr halt 8 , 156.Xr reboot 8 157.Sh BACKWARD COMPATIBILITY 158The hours and minutes in the second time format may be separated by 159a colon (``:'') for backward compatibility. 160.Sh HISTORY 161The 162.Nm 163command appeared in 164.Bx 4.0 . 165