xref: /freebsd/share/man/man9/kern_reboot.9 (revision f7c32ed617858bcd22f8d1b03199099d50125721)
1.\"	$NetBSD: boot.9,v 1.2 1996/09/24 07:01:26 ghudson Exp $
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3.\" Copyright (c) 1997
4.\" 	Mike Pritchard.  All rights reserved.
5.\"
6.\" Copyright (c) 1994 Christopher G. Demetriou
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19.\"      This product includes software developed by Christopher G. Demetriou
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35.\" $FreeBSD$
36.\"
37.Dd Sept 23, 2021
38.Dt KERN_REBOOT 9
39.Os
40.Sh NAME
41.Nm kern_reboot
42.Nd halt or reboot the system
43.Sh SYNOPSIS
44.In sys/types.h
45.In sys/systm.h
46.In sys/reboot.h
47.Ft void
48.Fn kern_reboot "int howto"
49.In sys/eventhandler.h
50.Fn EVENTHANDLER_REGISTER "shutdown_pre_sync" "shutdown_fn" "private" "priority"
51.Fn EVENTHANDLER_REGISTER "shutdown_post_sync" "shutdown_fn" "private" "priority"
52.Fn EVENTHANDLER_REGISTER "shutdown_final" "shutdown_fn" "private" "priority"
53.Sh DESCRIPTION
54The
55.Fn kern_reboot
56function handles final system shutdown, and either halts or reboots
57the system.
58The exact action to be taken is determined by the flags passed in
59.Fa howto
60and by whether or not the system has finished autoconfiguration.
61.Pp
62If the system has finished autoconfiguration,
63.Fn kern_reboot
64does the following:
65.Bl -enum -offset indent
66.It
67If this is the first invocation of
68.Fn kern_reboot
69and the
70.Dv RB_NOSYNC
71flag is not set in
72.Fa howto ,
73syncs and unmounts the system disks by calling
74.Xr vfs_unmountall 9 .
75.It
76Disables interrupts.
77.It
78If rebooting after a crash (i.e., if
79.Dv RB_DUMP
80is set in
81.Fa howto ,
82but
83.Dv RB_HALT
84is not), saves a system crash dump.
85.It
86Runs any shutdown hooks previously registered.
87.It
88Prints a message indicating that the system is about to be halted
89or rebooted.
90.It
91If
92.Dv RB_HALT
93is set in
94.Fa howto ,
95halts the system.
96Otherwise, reboots the system.
97.El
98.Pp
99If the system has not finished autoconfiguration,
100.Fn kern_reboot
101runs any shutdown hooks previously registered,
102prints a message, and halts the system.
103.Sh RETURN VALUES
104The
105.Fn kern_reboot
106function does not return.
107.Sh SEE ALSO
108.Xr reboot 2
109.Xr EVENTHANDLER 9
110.Xr vfs_unmountall 9
111