xref: /freebsd/share/man/man9/kern_reboot.9 (revision 800e74955d4e5f90e7258956ba42228350f71049)

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.\" Copyright (c) 1997
.\" 	Mike Pritchard.  All rights reserved.
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.\" Copyright (c) 1994 Christopher G. Demetriou
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.Dd Sept 23, 2021
.Dt KERN_REBOOT 9
.Os
.Sh NAME
.Nm kern_reboot
.Nd halt or reboot the system
.Sh SYNOPSIS
.In sys/types.h
.In sys/systm.h
.In sys/reboot.h
.Ft void
.Fn kern_reboot "int howto"
.In sys/eventhandler.h
.Fn EVENTHANDLER_REGISTER "shutdown_pre_sync" "shutdown_fn" "private" "priority"
.Fn EVENTHANDLER_REGISTER "shutdown_post_sync" "shutdown_fn" "private" "priority"
.Fn EVENTHANDLER_REGISTER "shutdown_final" "shutdown_fn" "private" "priority"
.Sh DESCRIPTION
The
.Fn kern_reboot
function handles final system shutdown, and either halts or reboots
the system.
The exact action to be taken is determined by the flags passed in
.Fa howto
and by whether or not the system has finished autoconfiguration.
.Pp
If the system has finished autoconfiguration,
.Fn kern_reboot
does the following:
.Bl -enum -offset indent
.It
If this is the first invocation of
.Fn kern_reboot
and the
.Dv RB_NOSYNC
flag is not set in
.Fa howto ,
syncs and unmounts the system disks by calling
.Xr vfs_unmountall 9 .
.It
Disables interrupts.
.It
If rebooting after a crash (i.e., if
.Dv RB_DUMP
is set in
.Fa howto ,
but
.Dv RB_HALT
is not), saves a system crash dump.
.It
Runs any shutdown hooks previously registered.
.It
Prints a message indicating that the system is about to be halted
or rebooted.
.It
If
.Dv RB_HALT
is set in
.Fa howto ,
halts the system.
Otherwise, reboots the system.
.El
.Pp
If the system has not finished autoconfiguration,
.Fn kern_reboot
runs any shutdown hooks previously registered,
prints a message, and halts the system.
.Sh RETURN VALUES
The
.Fn kern_reboot
function does not return.
.Sh SEE ALSO
.Xr reboot 2
.Xr EVENTHANDLER 9
.Xr vfs_unmountall 9