REBOOT(2)REBOOT(2)NAMEreboot - reboot system or halt processor
SYNOPSIS
#include <sys/reboot.h>
reboot(howto)
int howto;
DESCRIPTION
Reboot reboots the system, and is invoked automatically in the event of
unrecoverable system failures. Howto is a mask of options passed to
the bootstrap program. The system call interface permits only RB_HALT
or RB_AUTOBOOT to be passed to the reboot program; the other flags are
used in scripts stored on the console storage media, or used in manual
bootstrap procedures. When none of these options (e.g. RB_AUTOBOOT) is
given, the system is rebooted from file “mach” 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 then normally performed.
The bits of howto are:
RB_HALT
The processor is simply halted; no reboot takes place. RB_HALT
should be used with caution.
RB_ASKNAME
Interpreted by the bootstrap program itself, causing it to
inquire as to what file should be booted. Normally, the system
is booted from the file “xx(0,0)mach” without asking.
RB_SINGLE
Normally, the reboot procedure involves an automatic disk
consistency check and then multi-user operations. RB_SINGLE
prevents the consistency check, rather simply booting the system
with a single-user shell on the console. RB_SINGLE is
interpreted by the init(8) program in the newly booted system.
This switch is not available from the system call interface.
RB_POWERDOWN
The processor will be powered down after a halt takes place.
RB_COMMAND
A reboot takes place using the boot command string pointed to by
an extra argument, command. Normally the system is rebooted
using the previous boot command, but this option allows programs
such as reboot(8) to specify a new boot command without
requiring the user to halt the system and enter the new boot
command from the console. When RB_COMMAND is specified, reboot
should be called as follows:
reboot(howto, command)
int howto;
char *command;
Only the super-user may reboot a machine.
RETURN VALUES
If successful, this call never returns. Otherwise, a -1 is returned
and an error is returned in the global variable errno.
ERRORS
[EPERM] The caller is not the super-user.
SEE ALSOcrash(8), halt(8), init(8), reboot(8)4th Berkeley Distribution Febuary 5, 1990 REBOOT(2)
