1.\" $NetBSD: boot.9,v 1.2 1996/09/24 07:01:26 ghudson Exp $ 2.\" 3.\" Copyright (c) 1997 4.\" Mike Pritchard. All rights reserved. 5.\" 6.\" Copyright (c) 1994 Christopher G. Demetriou 7.\" All rights reserved. 8.\" 9.\" Redistribution and use in source and binary forms, with or without 10.\" modification, are permitted provided that the following conditions 11.\" are met: 12.\" 1. Redistributions of source code must retain the above copyright 13.\" notice, this list of conditions and the following disclaimer. 14.\" 2. Redistributions in binary form must reproduce the above copyright 15.\" notice, this list of conditions and the following disclaimer in the 16.\" documentation and/or other materials provided with the distribution. 17.\" 3. All advertising materials mentioning features or use of this software 18.\" must display the following acknowledgement: 19.\" This product includes software developed by Christopher G. Demetriou 20.\" for the NetBSD Project. 21.\" 3. The name of the author may not be used to endorse or promote products 22.\" derived from this software without specific prior written permission 23.\" 24.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 25.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 26.\" OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 27.\" IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 28.\" INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 29.\" NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 30.\" DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 31.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 32.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 33.\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 34.\" 35.Dd September 23, 2021 36.Dt KERN_REBOOT 9 37.Os 38.Sh NAME 39.Nm kern_reboot 40.Nd halt or reboot the system 41.Sh SYNOPSIS 42.In sys/types.h 43.In sys/systm.h 44.In sys/reboot.h 45.Ft void 46.Fn kern_reboot "int howto" 47.In sys/eventhandler.h 48.Fn EVENTHANDLER_REGISTER "shutdown_pre_sync" "shutdown_fn" "private" "priority" 49.Fn EVENTHANDLER_REGISTER "shutdown_post_sync" "shutdown_fn" "private" "priority" 50.Fn EVENTHANDLER_REGISTER "shutdown_final" "shutdown_fn" "private" "priority" 51.Sh DESCRIPTION 52The 53.Fn kern_reboot 54function handles final system shutdown, and either halts or reboots 55the system. 56The exact action to be taken is determined by the flags passed in 57.Fa howto 58and by whether or not the system has finished autoconfiguration. 59.Pp 60If the system has finished autoconfiguration, 61.Fn kern_reboot 62does the following: 63.Bl -enum -offset indent 64.It 65If this is the first invocation of 66.Fn kern_reboot 67and the 68.Dv RB_NOSYNC 69flag is not set in 70.Fa howto , 71syncs and unmounts the system disks by calling 72.Xr vfs_unmountall 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 84Runs any shutdown hooks previously registered. 85.It 86Prints a message indicating that the system is about to be halted 87or rebooted. 88.It 89If 90.Dv RB_HALT 91is set in 92.Fa howto , 93halts the system. 94Otherwise, reboots the system. 95.El 96.Pp 97If the system has not finished autoconfiguration, 98.Fn kern_reboot 99runs any shutdown hooks previously registered, 100prints a message, and halts the system. 101.Sh RETURN VALUES 102The 103.Fn kern_reboot 104function does not return. 105.Sh SEE ALSO 106.Xr reboot 2 , 107.Xr EVENTHANDLER 9 , 108.Xr vfs_unmountall 9 109