Differences between current version and predecessor to the previous major change of reboot(2).
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| Newer page: | version 2 | Last edited on Monday, March 17, 2003 12:11:44 am | by PerryLorier | |
| Older page: | version 1 | Last edited on Tuesday, June 4, 2002 12:23:44 am | by perry | Revert |
@@ -1,156 +1,55 @@
-REBOOT
-!!!REBOOT
-NAME
-SYNOPSIS
-DESCRIPTION
-RETURN VALUE
-ERRORS
-CONFORMING TO
-SEE ALSO
-----
!!NAME
+reboot - reboot or enable/disable Ctrl-Alt-Del
-
-reboot - reboot or enable/disable Ctrl-Alt-Del
!!SYNOPSIS
+For libc4 and libc5 the library call and the system call are identical, and since kernel version 2.1.30 there are symbolic names LINUX_REBOOT_* for the constants and a fourth argument to the call:
+ __#include <unistd.h>__
+ __#include <linux/reboot.h>__
-For libc4 and libc5 the library call and the system call are
-identical, and since kernel version 2.1.30 there are
-symbolic names LINUX_REBOOT_* for the constants and a fourth
-argument to the call:
+ __int reboot (int__ ''magic''__, int__ ''magic2''__, int__ ''flag''__, void *__''arg''__);__
-__#include __
-#include __
+Under glibc some of the constants involved have gotten symbolic names RB
_*, and the library call is a 1-argument wrapper around the 3-argument system call:
+ __#include <unistd.h>__
+ __#include <sys/reboot.h>__
-__int reboot (int__ ''magic''__, int__
-''magic2''__, int__ ''flag''__, void
-*__''arg''__);__
-
-Under glibc some of the constants involved have gotten
-symbolic names RB_*, and the library call is a 1-argument
-wrapper around the 3-argument system call:
-
-
-__#include __
-#include __
-
-
-
+
__int reboot (int__ ''flag''__);__
!!DESCRIPTION
+The __reboot__ call reboots the system, or enables/disables the reboot keystroke (abbreviated CAD, since the default is Ctrl-Alt-Delete; it can be changed using loadkeys(1)).
+This system call will fail (with [EINVAL]) unless ''magic'' equals LINUX_REBOOT_MAGIC1 (that is, 0xfee1dead) and ''magic2'' equals LINUX_REBOOT_MAGIC2 (that is,
+672274793). However, since 2.1.17 also LINUX_REBOOT_MAGIC2A (that is, 85072278) and since 2.1.97 also LINUX_REBOOT_MAGIC2B (that is, 369367448) are permitted as
+value for ''magic2''. (The hexadecimal values of these constants are meaningful.) The ''flag'' argument can have the following values:
-The
__reboot
__ call reboots the system, or
-enables/disables the reboot keystroke
(abbreviated CAD
,
-since the
default is Ctrl-Alt-Delete; it can be changed
-using loadkeys
(1)
).
+;
__LINUX
_REBOOT
_CMD_RESTART__:
(RB_AUTOBOOT, 0x1234567). The message `Restarting system.' is printed
, and a
default restart
is performed immediately. If not preceded by a sync
(2
), data will be lost
.
+;__LINUX_REBOOT_CMD_HALT__: (RB_HALT_SYSTEM, 0xcdef0123; since 1.1.76). The message `System halted.' is printed, and the system is halted. Control is given to the ROM monitor, if there is one. If not preceded by a sync(2), data will be lost.
-This system call will fail (with EINVAL) unless ''magic''
-equals LINUX
_REBOOT
_MAGIC1 (that is, 0xfee1dead) and
-''magic2'' equals
LINUX_REBOOT_MAGIC2
(that is,
-672274793). However,
since 2.1.17 also LINUX_REBOOT_MAGIC2A
-(that is, 85072278
) and since 2
.1
.97 also
-LINUX_REBOOT_MAGIC2B (that
is, 369367448) are permitted as
-value for ''magic2''
. (The hexadecimal values of these
-constants are meaningful
.) The ''flag'' argument can have
-the following values:
+;
__LINUX_REBOOT_CMD_POWER_OFF__:
(0x4321fedc;
since 2.1.30
). The message `Power down
.'
is printed
, the system is stopped, and all power is removed from the system, if possible
. If not preceded by a sync
(2), data will be lost
.
+;__LINUX_REBOOT_CMD_RESTART2__: (0xa1b2c3d4; since 2.1.30). The message `Restarting system with command '%s'' is printed, and a restart (using the command string given in ''arg'') is performed immediately. If not preceded by a sync(2), data will be lost.
-__LINUX_REBOOT_CMD_RESTART__
-
-
-(RB_AUTOBOOT, 0x1234567). The message `Restarting system.'
-is printed, and a default restart is performed immediately.
-If not preceded by a sync(2), data will be
-lost.
-
-
-__LINUX_REBOOT_CMD_HALT__
-
-
-(RB_HALT_SYSTEM, 0xcdef0123; since 1.1.76). The message
-`System halted.' is printed, and the system is halted.
-Control is given to the ROM monitor, if there is one. If not
-preceded by a sync(2), data will be
-lost.
-
-
-__LINUX_REBOOT_CMD_POWER_OFF__
-
-
-(0x4321fedc; since 2.1.30). The message `Power down.' is
-printed, the system is stopped, and all power is removed
-from the system, if possible. If not preceded by a
-sync(2), data will be lost.
-
-
-__LINUX_REBOOT_CMD_RESTART2__
-
-
-(0xa1b2c3d4; since 2.1.30). The message `Restarting system
-with command '%s'' is printed, and a restart (using the
-command string given in ''arg'') is performed
-immediately. If not preceded by a sync(2), data will
-be lost.
-
-
-
-
-
-
-
-.
-
-
-__LINUX_REBOOT_CMD_CAD_OFF__
-
-
-(RB_DISABLE_CAD, ). CAD is disabled. This means that the
-CAD keystroke will cause a SIGINT signal to be sent to init
-(process 1), whereupon this process may decide upon a proper
-action (maybe: kill all processes, sync,
-reboot)
.
+:
__LINUX_REBOOT_CMD_CAD_ON__:
(RB_ENABLE_CAD, 0x89abcdef). CAD is enabled. This means that the CAD keystroke will immediately cause the action associated to LINUX_REBOOT_CMD_RESTART.
+;__LINUX_REBOOT_CMD_CAD_OFF__: (RB_DISABLE_CAD, 0). CAD is disabled. This means that the CAD keystroke will cause a SIGINT signal to be sent to init (process 1), whereupon this process may decide upon a proper action (maybe: kill all processes, sync, reboot).
Only the super-user may use this function.
+The precise effect of the above actions depends on the architecture. For the i386 architecture, the additional argument does not do anything at present (2.1.122), but the
+type of reboot can be determined by kernel command line arguments (`reboot=...') to be either warm or cold, and either hard or through the BIOS.
-The precise effect of the above actions depends on the
-architecture. For the i386 architecture, the additional
-argument does not do anything at present (2.1.122), but the
-type of reboot can be determined by kernel command line
-arguments (`reboot=...') to be either warm or cold, and
-either hard or through the BIOS.
!!RETURN VALUE
+On success, zero is returned. On error, -1 is returned, and ''errno'' is set appropriately.
-
-On success, zero is returned. On error, -1 is returned, and
-''errno'' is set appropriately.
!!ERRORS
+;[EINVAL]: Bad magic numbers or ''flag''.
+;[EPERM]: A non-root user attempts to call __reboot__.
-
-__EINVAL__
-
-
-Bad magic numbers or ''flag''.
-
-
-__EPERM__
-
-
-A non-root user attempts to call __reboot__.
!!CONFORMING TO
+reboot(2) is Linux specific, and should not be used in programs intended to be portable.
-
-__reboot__ is Linux specific, and should not be used in
-programs intended to be portable.
!!SEE ALSO
-
-
-
-
-----
+sync(2), bootparam(7), ctrlaltdel(8), halt(8), reboot(8)
