usr/src/sbin/reboot/halt.8

.\" Copyright (c) 1980, 1991 The Regents of the University of California.
.\" All rights reserved.
.\"
.\" %sccs.include.redist.man%
.\"
.\"     @(#)halt.8      6.5 (Berkeley) %G%
.\"
.Dd
.Dt HALT 8
.Os BSD 4
.Sh NAME
.Nm halt
.Nd stop the processor
.Sh SYNOPSIS
.Nm halt
.Op Fl n
.Op Fl q
.Op Fl y
.Sh DESCRIPTION
.Nm Halt
writes out sandbagged information to the disks and then stops
the processor.  The machine does not reboot, even if the auto-reboot
switch is set on the console.
.Pp
Available options for
.Nm halt :
.Bl -tag -width Ds
.It Fl n
No sync before stopping.
.It Fl q
Quick halt, no graceful shutdown is attempted.
.It Fl y
This option is needed if you are trying to halt the system from a dialup.
.El
.Pp
.Nm Halt
normally logs the shutdown using
.Xr syslog 8
and places a shutdown record in the login accounting file
.Pa /var/log/wtmp.
These actions are inhibited if the
.Fl n
or
.Fl q
options are present.
.Sh SEE ALSO
.Xr reboot 8 ,
.Xr shutdown 8 ,
.Xr syslogd 8
.Sh BUGS
It is very difficult to halt a
.Tn VAX ,
as the machine wants to then
reboot itself.  A rather tight loop suffices.
.Sh HISTORY
The
.Nm
command appeared in
.Bx 4.0 .