CPU_REBOOT(9) BSD Kernel Developer's Manual CPU_REBOOT(9)NAME
cpu_reboot -- halt or reboot the system
SYNOPSIS
#include <sys/reboot.h>
void
cpu_reboot(int howto, char *bootstr);
DESCRIPTION
The cpu_reboot() function handles final system shutdown, and either halts or reboots the system. The exact action to be taken is determined
by the flags passed in howto and by whether or not the system has finished autoconfiguration.
If the system has finished autoconfiguration, cpu_reboot() does the following:
1. Sets the boothowto system variable (see boothowto(9)) from the howto argument.
2. If this is the first invocation of cpu_reboot() and the RB_NOSYNC flag is not set in howto, syncs and unmounts the system disks by
calling vfs_shutdown(9) and sets the time of day clock by calling resettodr(9).
3. Disables interrupts.
4. If rebooting after a crash (i.e., if RB_DUMP is set in howto, but RB_HALT is not), saves a system crash dump.
5. Runs any shutdown hooks by calling pmf_system_shutdown(9).
6. Prints a message indicating that the system is about to be halted or rebooted.
7. If RB_HALT is set in howto, halts the system. Otherwise, reboots the system.
If the system has not finished autoconfiguration, cpu_reboot() runs any shutdown hooks by calling pmf_system_shutdown(9), prints a message,
and halts the system.
If RB_STRING is set in howto, then the parameter bootstr is passed to the system boot loader on some ports.
SEE ALSO boothowto(9), dumpsys(9), pmf_system_shutdown(9), resettodr(9), vfs_shutdown(9)BSD February 11, 2010 BSD
Check Out this Related Man Page
REBOOT(2) BSD System Calls Manual REBOOT(2)NAME
reboot -- reboot system or halt processor
LIBRARY
Standard C Library (libc, -lc)
SYNOPSIS
#include <unistd.h>
#include <sys/reboot.h>
int
reboot(int howto, char *bootstr);
DESCRIPTION
reboot() 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.
howto is a mask of options; the system call interface allows the following options, defined in the include file <sys/reboot.h>, to be passed
to the new kernel or the new bootstrap and init programs. In addition to the options described below, other options described in
boothowto(9) may be set, but such options may be ignored by the system.
Options can be combined together by OR'ing them, eg. RB_DUMP | RB_NOSYNC would be interpreted as ``dump kernel memory before rebooting and
don't sync the disks''.
RB_AUTOBOOT 0x0000 The default, causing the system to reboot in its usual fashion.
RB_ASKNAME 0x0001 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 ``xx(0,0)netbsd'', where xx is the default disk name, without prompt-
ing for the file name.
RB_DUMP 0x0100 Dump kernel memory before rebooting; see savecore(8) for more information.
RB_HALT 0x0008 the processor is simply halted; no reboot takes place. This option should be used with caution.
RB_POWERDOWN 0x0808 This option is always used in conjunction with RB_HALT, and if the system hardware supports the function, the sys-
tem will be powered off, otherwise it has no effect.
RB_INITNAME 0x0010 An option allowing the specification of an init program (see init(8)) other than /sbin/init to be run when the sys-
tem reboots. This switch is not currently available.
RB_KDB 0x0040 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 reboot() call. See ddb(4) for more information.
RB_NOSYNC 0x0004 Normally, the disks are sync'd (see 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.
RB_RDONLY 0x0080 Initially mount the root file system read-only. This is currently the default, and this option has been depre-
cated.
RB_SINGLE 0x0002 Normally, the reboot procedure involves an automatic disk consistency check and then multi-user operations.
RB_SINGLE prevents this, booting the system with a single-user shell on the console. RB_SINGLE is actually inter-
preted by the init(8) program in the newly booted system.
When no options are given (i.e., RB_AUTOBOOT is used), the system is rebooted from file ``netbsd'' 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 nor-
mally performed (see fsck(8)).
RB_STRING 0x0400 bootstr is a string passed to the firmware on the machine, if possible, if this option is set. Currently this is
only implemented on the sparc and the sun3 ports.
RB_USERCONF 0x1000 Initially invoke the userconf(4) facility when the system starts up again, if it has been compiled into the kernel
that is loaded.
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 ALSO ddb(4), crash(8), halt(8), init(8), reboot(8), savecore(8), boothowto(9)HISTORY
The reboot() function call appeared in 4.0BSD.
The RB_DFLTROOT option is now obsolete.
BSD September 4, 2009 BSD