.\"	$OpenBSD: reboot.8,v 1.35 2006/04/08 08:53:08 jmc Exp $
.\"	$NetBSD: reboot.8,v 1.3 1995/10/05 05:36:21 mycroft Exp $
.\"
.\" Copyright (c) 1990, 1991, 1993
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.\"	@(#)reboot.8	8.1 (Berkeley) 6/9/93
.\"
.Dd June 9, 1993
.Dt REBOOT 8
.Os
.Sh NAME
.Nm reboot ,
.Nm halt
.Nd stopping and restarting the system
.Sh SYNOPSIS
.Nm halt
.Op Fl dnpq
.Nm reboot
.Op Fl dnq
.Sh DESCRIPTION
The
.Nm halt
and
.Nm reboot
utilities flush the file system cache to disk, run the system
shutdown script, send all running processes a
.Dv SIGTERM
.Pq and subsequently a Dv SIGKILL ,
and, respectively, halt or restart the system.
The action is logged, including entering a shutdown record into the login
accounting file.
.Pp
The options are as follows:
.Bl -tag -width Ds
.It Fl d
Causes system to create a dump before rebooting.
This option is useful for debugging system dump procedures or
capturing the state of a corrupted or misbehaving system.
See
.Xr savecore 8
for information on how to recover this dump.
.It Fl n
Prevent file system cache from being flushed.
This option should probably not be used.
.It Fl p
Causes the system to power down, if it is being halted, and the
hardware supports automatic power down.
(Currently supported on some i386, luna88k, mac68k, macppc,
sparc, sparc64 and zaurus platforms.)
.Pp
See also the description of
.Va powerdown ,
below.
.It Fl q
Quick.
The system is halted or restarted quickly and ungracefully, and only
the flushing of the file system cache is performed.
This option should probably not be used.
.El
.Pp
Normally, the
.Xr shutdown 8
utility is used when the system needs to be halted or restarted, giving
users advance warning of their impending doom.
.Sh FILES
.Bl -tag -width /etc/rc.shutdown -compact
.It Pa /etc/rc.shutdown
Script which is run at shutdown time.
If it sets the variable
.Va powerdown
to
.Dq YES ,
.Nm halt
will attempt to power down the machine after it has halted.
.El
.Sh SEE ALSO
.Xr reboot 2 ,
.Xr utmp 5 ,
.\" .Xr boot 8 ,
.Xr boot_alpha 8 ,
.Xr boot_amd64 8 ,
.Xr boot_cats 8 ,
.Xr boot_hp300 8 ,
.Xr boot_hppa 8 ,
.Xr boot_hppa64 8 ,
.Xr boot_i386 8 ,
.Xr boot_luna88k 8 ,
.Xr boot_mac68k 8 ,
.Xr boot_macppc 8 ,
.Xr boot_mvme68k 8 ,
.Xr boot_mvme88k 8 ,
.\" .Xr boot_mvmeppc 8 ,
.Xr boot_sparc 8 ,
.Xr boot_sparc64 8 ,
.Xr boot_vax 8 ,
.Xr boot_zaurus 8 ,
.Xr rc.shutdown 8 ,
.Xr savecore 8 ,
.Xr shutdown 8 ,
.Xr sync 8
.Sh HISTORY
A
.Nm reboot
command appeared in
.At v6 .