Penguin
Recent Changes
Annotated edit history of reboot(2) version 2, including all changes. View license author blame.
Rev Author # Line
1 perry 1 !!NAME
2 PerryLorier 2 reboot - reboot or enable/disable Ctrl-Alt-Del
1 perry 3
4 !!SYNOPSIS
2 PerryLorier 5 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:
1 perry 6
2 PerryLorier 7 __#include <unistd.h>__
8 __#include <linux/reboot.h>__
1 perry 9
10
2 PerryLorier 11 __int reboot (int__ ''magic''__, int__ ''magic2''__, int__ ''flag''__, void *__''arg''__);__
1 perry 12
2 PerryLorier 13 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:
1 perry 14
2 PerryLorier 15 __#include <unistd.h>__
16 __#include <sys/reboot.h>__
1 perry 17
18
2 PerryLorier 19 __int reboot (int__ ''flag''__);__
1 perry 20 !!DESCRIPTION
2 PerryLorier 21 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)).
1 perry 22
2 PerryLorier 23 This system call will fail (with [EINVAL]) unless ''magic'' equals LINUX_REBOOT_MAGIC1 (that is, 0xfee1dead) and ''magic2'' equals LINUX_REBOOT_MAGIC2 (that is,
24 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
25 value for ''magic2''. (The hexadecimal values of these constants are meaningful.) The ''flag'' argument can have the following values:
1 perry 26
2 PerryLorier 27 ;__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.
1 perry 28
2 PerryLorier 29 ;__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.
1 perry 30
2 PerryLorier 31 ;__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.
1 perry 32
2 PerryLorier 33 ;__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.
1 perry 34
2 PerryLorier 35 :__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.
1 perry 36
2 PerryLorier 37 ;__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).
1 perry 38
39 Only the super-user may use this function.
40
2 PerryLorier 41 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
42 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.
1 perry 43
44 !!RETURN VALUE
2 PerryLorier 45 On success, zero is returned. On error, -1 is returned, and ''errno'' is set appropriately.
1 perry 46
47 !!ERRORS
2 PerryLorier 48 ;[EINVAL]: Bad magic numbers or ''flag''.
49 ;[EPERM]: A non-root user attempts to call __reboot__.
1 perry 50
51 !!CONFORMING TO
2 PerryLorier 52 reboot(2) is Linux specific, and should not be used in programs intended to be portable.
1 perry 53
54 !!SEE ALSO
2 PerryLorier 55 sync(2), bootparam(7), ctrlaltdel(8), halt(8), reboot(8)
This page is a man page (or other imported legacy content). We are unable to automatically determine the license status of this page.

PHP Warning

lib/blame.php:177: Warning: Invalid argument supplied for foreach() (...repeated 8 times)