1.\" $OpenBSD: boot.9,v 1.10 2014/12/10 15:29:52 mikeb Exp $ 2.\" $NetBSD: boot.9,v 1.1 1995/11/25 21:24:48 perry Exp $ 3.\" 4.\" Copyright (c) 1994 Christopher G. Demetriou 5.\" All rights reserved. 6.\" 7.\" Redistribution and use in source and binary forms, with or without 8.\" modification, are permitted provided that the following conditions 9.\" are met: 10.\" 1. Redistributions of source code must retain the above copyright 11.\" notice, this list of conditions and the following disclaimer. 12.\" 2. Redistributions in binary form must reproduce the above copyright 13.\" notice, this list of conditions and the following disclaimer in the 14.\" documentation and/or other materials provided with the distribution. 15.\" 3. All advertising materials mentioning features or use of this software 16.\" must display the following acknowledgement: 17.\" This product includes software developed by Christopher G. Demetriou 18.\" for the NetBSD Project. 19.\" 3. The name of the author may not be used to endorse or promote products 20.\" derived from this software without specific prior written permission 21.\" 22.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 23.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 24.\" OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 25.\" IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 26.\" INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 27.\" NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 28.\" DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 29.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 30.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 31.\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 32.\" 33.Dd $Mdocdate: December 10 2014 $ 34.Dt BOOT 9 35.Os 36.Sh NAME 37.Nm boot 38.Nd halt or reboot the system 39.Sh SYNOPSIS 40.In sys/reboot.h 41.Ft void 42.Fn boot "int howto" 43.Sh DESCRIPTION 44The 45.Fn boot 46function handles final system shutdown, and either halts or reboots 47the system. 48The exact action to be taken is determined by the flags passed in 49.Fa howto 50and by whether or not the system has finished autoconfiguration. 51.Pp 52If the system has finished autoconfiguration, 53.Fn boot 54does the following: 55.Bl -enum -offset indent 56.It 57Sets the 58.Va boothowto 59system variable from the 60.Fa howto 61argument. 62.It 63If this is the first invocation of 64.Fn boot 65and the 66.Dv RB_NOSYNC 67flag is not set in 68.Fa howto , 69syncs and unmounts the system disks by calling 70.Fn vfs_shutdown 71and sets the time of day clock by calling 72.Xr resettodr 9 . 73.It 74Disables interrupts. 75.It 76If rebooting after a crash (i.e., if 77.Dv RB_DUMP 78is set in 79.Fa howto , 80but 81.Dv RB_HALT 82is not), saves a system crash dump. 83.It 84Prints a message indicating that the system is about to be halted 85or rebooted. 86.It 87If 88.Dv RB_HALT 89is set in 90.Fa howto , 91halts the system. 92Otherwise, reboots the system. 93.El 94.Pp 95If the system has not finished autoconfiguration, 96.Fn boot 97prints a message, and halts the system 98(unless 99.Dv RB_USERREQ 100is specified, in which case the system will be halted if 101.Dv RB_HALT 102is given, and rebooted otherwise; see 103.Xr reboot 2 104for more details). 105.Sh SEE ALSO 106.Xr reboot 2 , 107.Xr resettodr 9 108