1994-05-27 05:00:24 +00:00
|
|
|
.\" Copyright (c) 1980, 1991, 1993
|
|
|
|
.\" The Regents of the University of California. All rights reserved.
|
|
|
|
.\"
|
|
|
|
.\" Redistribution and use in source and binary forms, with or without
|
|
|
|
.\" modification, are permitted provided that the following conditions
|
|
|
|
.\" are met:
|
|
|
|
.\" 1. Redistributions of source code must retain the above copyright
|
|
|
|
.\" notice, this list of conditions and the following disclaimer.
|
|
|
|
.\" 2. Redistributions in binary form must reproduce the above copyright
|
|
|
|
.\" notice, this list of conditions and the following disclaimer in the
|
|
|
|
.\" documentation and/or other materials provided with the distribution.
|
2017-02-28 23:42:47 +00:00
|
|
|
.\" 3. Neither the name of the University nor the names of its contributors
|
1994-05-27 05:00:24 +00:00
|
|
|
.\" may be used to endorse or promote products derived from this software
|
|
|
|
.\" without specific prior written permission.
|
|
|
|
.\"
|
|
|
|
.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
|
|
|
|
.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
|
|
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
|
|
.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
|
|
|
|
.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
|
|
|
.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
|
|
|
.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
|
|
|
.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
|
|
|
.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
|
|
|
.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
|
|
|
.\" SUCH DAMAGE.
|
|
|
|
.\"
|
|
|
|
.\" @(#)reboot.2 8.1 (Berkeley) 6/4/93
|
1999-08-28 00:22:10 +00:00
|
|
|
.\" $FreeBSD$
|
1994-05-27 05:00:24 +00:00
|
|
|
.\"
|
2018-07-10 00:01:14 +00:00
|
|
|
.Dd July 10, 2018
|
1994-05-27 05:00:24 +00:00
|
|
|
.Dt REBOOT 2
|
2001-07-10 13:41:46 +00:00
|
|
|
.Os
|
1994-05-27 05:00:24 +00:00
|
|
|
.Sh NAME
|
|
|
|
.Nm reboot
|
|
|
|
.Nd reboot system or halt processor
|
2000-04-21 09:42:15 +00:00
|
|
|
.Sh LIBRARY
|
|
|
|
.Lb libc
|
1994-05-27 05:00:24 +00:00
|
|
|
.Sh SYNOPSIS
|
2001-10-01 16:09:29 +00:00
|
|
|
.In unistd.h
|
|
|
|
.In sys/reboot.h
|
1994-05-27 05:00:24 +00:00
|
|
|
.Ft int
|
|
|
|
.Fn reboot "int howto"
|
|
|
|
.Sh DESCRIPTION
|
2002-12-18 09:22:32 +00:00
|
|
|
The
|
|
|
|
.Fn reboot
|
|
|
|
system call
|
1994-05-27 05:00:24 +00:00
|
|
|
reboots the system.
|
|
|
|
Only the super-user may reboot a machine on demand.
|
|
|
|
However, a reboot is invoked
|
|
|
|
automatically in the event of unrecoverable system failures.
|
|
|
|
.Pp
|
2002-12-19 09:40:28 +00:00
|
|
|
The
|
|
|
|
.Fa howto
|
|
|
|
argument
|
1994-05-27 05:00:24 +00:00
|
|
|
is a mask of options; the system call interface allows the following
|
|
|
|
options, defined in the include file
|
2003-09-08 19:57:22 +00:00
|
|
|
.In sys/reboot.h ,
|
1994-05-27 05:00:24 +00:00
|
|
|
to be passed
|
|
|
|
to the new kernel or the new bootstrap and init programs.
|
2018-07-10 00:01:14 +00:00
|
|
|
.Bl -tag -width RB_POWERCYCLE
|
1994-05-27 05:00:24 +00:00
|
|
|
.It Dv RB_AUTOBOOT
|
|
|
|
The default, causing the system to reboot in its usual fashion.
|
|
|
|
.It Dv RB_ASKNAME
|
2018-07-10 00:01:14 +00:00
|
|
|
Normally the system only prompts the user if the loader specified root
|
|
|
|
file system has an error.
|
|
|
|
This flag forces it to always prompt the user for the root partition.
|
1994-05-27 05:00:24 +00:00
|
|
|
.It Dv RB_DFLTROOT
|
|
|
|
Use the compiled in root device.
|
|
|
|
Normally, the system uses the device from which it was booted
|
|
|
|
as the root device if possible.
|
|
|
|
(The default behavior is dependent on the ability of the bootstrap program
|
|
|
|
to determine the drive from which it was loaded, which is not possible
|
|
|
|
on all systems.)
|
|
|
|
.It Dv RB_DUMP
|
|
|
|
Dump kernel memory before rebooting; see
|
|
|
|
.Xr savecore 8
|
|
|
|
for more information.
|
|
|
|
.It Dv RB_HALT
|
2015-07-24 18:13:13 +00:00
|
|
|
The processor is simply halted; no reboot takes place.
|
1994-05-27 05:00:24 +00:00
|
|
|
This option should be used with caution.
|
2017-10-25 15:30:20 +00:00
|
|
|
.It Dv RB_POWERCYCLE
|
|
|
|
After halting, the shutdown code will do what it can to turn
|
|
|
|
off the power and then turn the power back on.
|
|
|
|
This requires hardware support, usually an auxiliary microprocessor
|
|
|
|
that can sequence the power supply.
|
|
|
|
At present only the
|
|
|
|
.Xr ipmi 4
|
|
|
|
driver implements this feature.
|
1996-08-22 03:50:33 +00:00
|
|
|
.It Dv RB_POWEROFF
|
|
|
|
After halting, the shutdown code will do what it can to turn
|
2000-06-13 12:50:47 +00:00
|
|
|
off the power.
|
2000-03-02 09:14:21 +00:00
|
|
|
This requires hardware support.
|
1994-05-27 05:00:24 +00:00
|
|
|
.It Dv RB_KDB
|
|
|
|
Load the symbol table and enable a built-in debugger in the system.
|
|
|
|
This option will have no useful function if the kernel is not configured
|
|
|
|
for debugging.
|
|
|
|
Several other options have different meaning if combined
|
|
|
|
with this option, although their use may not be possible
|
|
|
|
via the
|
|
|
|
.Fn reboot
|
2002-12-18 09:22:32 +00:00
|
|
|
system call.
|
1994-05-27 05:00:24 +00:00
|
|
|
See
|
2001-08-22 14:16:31 +00:00
|
|
|
.Xr ddb 4
|
1994-05-27 05:00:24 +00:00
|
|
|
for more information.
|
|
|
|
.It Dv RB_NOSYNC
|
|
|
|
Normally, the disks are sync'd (see
|
|
|
|
.Xr sync 8 )
|
|
|
|
before the processor is halted or rebooted.
|
|
|
|
This option may be useful if file system changes have been made manually
|
|
|
|
or if the processor is on fire.
|
2015-09-18 17:32:22 +00:00
|
|
|
.It Dv RB_REROOT
|
|
|
|
Instead of rebooting, unmount all filesystems except the one containing
|
|
|
|
currently-running executable, and mount root filesystem using the same
|
|
|
|
mechanism which is used during normal boot, based on
|
|
|
|
vfs.root.mountfrom
|
2016-02-29 17:22:34 +00:00
|
|
|
.Xr kenv 1
|
2015-09-18 17:32:22 +00:00
|
|
|
variable.
|
1994-05-27 05:00:24 +00:00
|
|
|
.It Dv RB_RDONLY
|
|
|
|
Initially mount the root file system read-only.
|
|
|
|
This is currently the default, and this option has been deprecated.
|
|
|
|
.It Dv RB_SINGLE
|
|
|
|
Normally, the reboot procedure involves an automatic disk consistency
|
|
|
|
check and then multi-user operations.
|
|
|
|
.Dv RB_SINGLE
|
|
|
|
prevents this, booting the system with a single-user shell
|
|
|
|
on the console.
|
|
|
|
.Dv RB_SINGLE
|
|
|
|
is actually interpreted by the
|
|
|
|
.Xr init 8
|
|
|
|
program in the newly booted system.
|
1999-09-05 06:50:49 +00:00
|
|
|
.El
|
1994-05-27 05:00:24 +00:00
|
|
|
.Pp
|
|
|
|
When no options are given (i.e.,
|
|
|
|
.Dv RB_AUTOBOOT
|
|
|
|
is used), the system is
|
1999-09-05 06:50:49 +00:00
|
|
|
rebooted from file
|
|
|
|
.Dq kernel
|
|
|
|
in the root file system of unit 0
|
1994-05-27 05:00:24 +00:00
|
|
|
of a disk chosen in a processor specific way.
|
|
|
|
An automatic consistency check of the disks is normally performed
|
|
|
|
(see
|
|
|
|
.Xr fsck 8 ) .
|
|
|
|
.Sh RETURN VALUES
|
|
|
|
If successful, this call never returns.
|
|
|
|
Otherwise, a -1 is returned and an error is returned in the global
|
|
|
|
variable
|
|
|
|
.Va errno .
|
|
|
|
.Sh ERRORS
|
|
|
|
.Bl -tag -width Er
|
|
|
|
.It Bq Er EPERM
|
|
|
|
The caller is not the super-user.
|
|
|
|
.El
|
|
|
|
.Sh SEE ALSO
|
|
|
|
.Xr crash 8 ,
|
|
|
|
.Xr halt 8 ,
|
|
|
|
.Xr init 8 ,
|
|
|
|
.Xr reboot 8 ,
|
2023-03-20 19:56:54 +00:00
|
|
|
.Xr savecore 8 ,
|
|
|
|
.Xr reboot 9
|
1994-05-27 05:00:24 +00:00
|
|
|
.Sh HISTORY
|
|
|
|
The
|
1996-08-22 23:31:07 +00:00
|
|
|
.Fn reboot
|
2002-12-18 09:22:32 +00:00
|
|
|
system call appeared in
|
1994-05-27 05:00:24 +00:00
|
|
|
.Bx 4.0 .
|