.\" $OpenBSD: reboot.2,v 1.2 1996/10/08 01:20:13 michaels Exp $ .\" $NetBSD: reboot.2,v 1.5 1995/02/27 12:36:02 cgd Exp $ .\" .\" 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. .\" 3. All advertising materials mentioning features or use of this software .\" must display the following acknowledgement: .\" This product includes software developed by the University of .\" California, Berkeley and its contributors. .\" 4. Neither the name of the University nor the names of its contributors .\" 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 .\" .Dd June 4, 1993 .Dt REBOOT 2 .Os BSD 4 .Sh NAME .Nm reboot .Nd reboot system or halt processor .Sh SYNOPSIS .Fd #include <unistd.h> .Fd #include <sys/reboot.h> .Ft int .Fn reboot "int howto" .Sh DESCRIPTION .Fn Reboot reboots the system. Only the super-user may reboot a machine on demand. However, a reboot may be invoked automatically in the event of unrecoverable system failures. Programs other than .Xr reboot 8 should not call .Fn reboot . .Xr Shutdown 8 or a higher-level API will shut the system down cleanly. .Pp .Fa Howto is a mask of options; the system call interface allows the following options, defined in the include file .Aq Pa sys/reboot.h , to be passed to the new kernel or the new bootstrap and init programs. .Bl -tag -width RB_INITNAMEA .It Dv RB_AUTOBOOT The default, causing the system to reboot in its usual fashion. .It Dv RB_ASKNAME Interpreted by the bootstrap program itself, causing it to prompt on the console as to what file should be booted. Normally, the system is booted from the file .Dq Em xx Ns No (0,0)bsd , where .Em xx is the default disk name, without prompting for the file name. .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 the processor is simply halted; no reboot takes place. This option should be used with caution. .It Dv RB_INITNAME An option allowing the specification of an init program (see .Xr init 8 ) other than .Pa /sbin/init to be run when the system reboots. This switch is not currently available. .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 call. See .Xr kadb 4 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. .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. .Pp When no options are given (i.e., .Dv RB_AUTOBOOT is used), the system is rebooted from file ``bsd'' in the root file system of unit 0 of a disk chosen in a processor specific way. An automatic consistency check of the disks is normally performed (see .Xr fsck 8 ) . .El .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 shutdown 8 , .Xr halt 8 , .Xr launchd 8 , .Xr reboot 8 .Sh BUGS The HP300 implementation supports neither .Dv RB_DFLTROOT nor .Dv RB_KDB . .Sh HISTORY The .Fn reboot function call appeared in .Bx 4.0 .