+++ /dev/null
-.\" Copyright (c) 1998 Andries Brouwer (aeb@cwi.nl), 24 September 1998
-.\"
-.\" %%%LICENSE_START(VERBATIM)
-.\" Permission is granted to make and distribute verbatim copies of this
-.\" manual provided the copyright notice and this permission notice are
-.\" preserved on all copies.
-.\"
-.\" Permission is granted to copy and distribute modified versions of this
-.\" manual under the conditions for verbatim copying, provided that the
-.\" entire resulting derived work is distributed under the terms of a
-.\" permission notice identical to this one.
-.\"
-.\" Since the Linux kernel and libraries are constantly changing, this
-.\" manual page may be incorrect or out-of-date. The author(s) assume no
-.\" responsibility for errors or omissions, or for damages resulting from
-.\" the use of the information contained herein. The author(s) may not
-.\" have taken the same level of care in the production of this manual,
-.\" which is licensed free of charge, as they might when working
-.\" professionally.
-.\"
-.\" Formatted or processed versions of this manual, if unaccompanied by
-.\" the source, must acknowledge the copyright and authors of this work.
-.\" %%%LICENSE_END
-.\"
-.\" Modified, 27 May 2004, Michael Kerrisk <mtk.manpages@gmail.com>
-.\" Added notes on capability requirements
-.\"
-.TH REBOOT 2 2015-02-01 "Linux" "Linux Programmer's Manual"
-.SH NAME
-reboot \- reboot or enable/disable Ctrl-Alt-Del
-.SH 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: */
-.sp
-.B #include <unistd.h>
-.br
-.B #include <linux/reboot.h>
-.sp
-.BI "int reboot(int " magic ", int " magic2 ", int " cmd ", void *" arg );
-.sp
-/* 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: */
-.sp
-.B #include <unistd.h>
-.br
-.B #include <sys/reboot.h>
-.sp
-.BI "int reboot(int " cmd );
-.SH DESCRIPTION
-The
-.BR 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
-.BR loadkeys (1)).
-.PP
-This system call will fail (with
-.BR EINVAL )
-unless
-.I magic
-equals
-.B LINUX_REBOOT_MAGIC1
-(that is, 0xfee1dead) and
-.I magic2
-equals
-.B LINUX_REBOOT_MAGIC2
-(that is, 672274793).
-However, since 2.1.17 also
-.B LINUX_REBOOT_MAGIC2A
-(that is, 85072278)
-and since 2.1.97 also
-.B LINUX_REBOOT_MAGIC2B
-(that is, 369367448)
-and since 2.5.71 also
-.B LINUX_REBOOT_MAGIC2C
-(that is, 537993216)
-are permitted as values for
-.IR magic2 .
-(The hexadecimal values of these constants are meaningful.)
-
-The
-.I cmd
-argument can have the following values:
-.TP
-.B LINUX_REBOOT_CMD_CAD_OFF
-.RB ( RB_DISABLE_CAD ,
-0).
-CAD is disabled.
-This means that the CAD keystroke will cause a
-.B SIGINT
-signal to be
-sent to init (process 1), whereupon this process may decide upon a
-proper action (maybe: kill all processes, sync, reboot).
-.TP
-.B LINUX_REBOOT_CMD_CAD_ON
-.RB ( RB_ENABLE_CAD ,
-0x89abcdef).
-CAD is enabled.
-This means that the CAD keystroke will immediately cause
-the action associated with
-.BR LINUX_REBOOT_CMD_RESTART .
-.TP
-.B LINUX_REBOOT_CMD_HALT
-.RB ( RB_HALT_SYSTEM ,
-0xcdef0123; since Linux 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
-.BR sync (2),
-data will be lost.
-.TP
-.BR LINUX_REBOOT_CMD_KEXEC
-.RB ( RB_KEXEC ,
-0x45584543, since Linux 2.6.13).
-Execute a kernel that has been loaded earlier with
-.BR kexec_load (2).
-This option is available only if the kernel was configured with
-.BR CONFIG_KEXEC .
-.TP
-.B LINUX_REBOOT_CMD_POWER_OFF
-.RB ( RB_POWER_OFF ,
-0x4321fedc; since Linux 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
-.BR sync (2),
-data will be lost.
-.TP
-.B LINUX_REBOOT_CMD_RESTART
-.RB ( RB_AUTOBOOT ,
-0x1234567).
-The message "Restarting system." is printed, and a default
-restart is performed immediately.
-If not preceded by a
-.BR sync (2),
-data will be lost.
-.TP
-.B LINUX_REBOOT_CMD_RESTART2
-(0xa1b2c3d4; since Linux 2.1.30).
-The message "Restarting system with command \(aq%s\(aq" is printed,
-and a restart (using the command string given in
-.IR arg )
-is performed immediately.
-If not preceded by a
-.BR sync (2),
-data will be lost.
-.TP
-.BR LINUX_REBOOT_CMD_SW_SUSPEND
-.RB ( RB_SW_SUSPEND ,
-0xd000fce1; since Linux 2.5.18).
-The system is suspended (hibernated) to disk.
-This option is available only if the kernel was configured with
-.BR CONFIG_HIBERNATION .
-.LP
-Only the superuser may call
-.BR reboot ().
-.LP
-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.
-.SS Behavior inside PID namespaces
-.\" commit cf3f89214ef6a33fad60856bc5ffd7bb2fc4709b
-.\" see also commit 923c7538236564c46ee80c253a416705321f13e3
-Since Linux 3.4, when
-.BR reboot ()
-is called from a PID namespace (see
-.BR pid_namespaces (7))
-other than the initial PID namespace,
-the effect of the call is to send a signal to the namespace "init" process.
-.BR LINUX_REBOOT_CMD_RESTART
-and
-.BR LINUX_REBOOT_CMD_RESTART2
-cause a
-.BR SIGHUP
-signal to be sent.
-.BR LINUX_REBOOT_CMD_POWER_OFF
-and
-.BR LINUX_REBOOT_CMD_HALT
-cause a
-.B SIGINT
-signal to be sent.
-.SH RETURN VALUE
-For the values of
-.I cmd
-that stop or restart the system,
-a successful call to
-.BR reboot ()
-does not return.
-For the other
-.I cmd
-values, zero is returned on success.
-In all cases, \-1 is returned on failure, and
-.I errno
-is set appropriately.
-.SH ERRORS
-.TP
-.B EFAULT
-Problem with getting user-space data under
-.BR LINUX_REBOOT_CMD_RESTART2 .
-.TP
-.B EINVAL
-Bad magic numbers or \fIcmd\fP.
-.TP
-.B EPERM
-The calling process has insufficient privilege to call
-.BR reboot ();
-the
-.B CAP_SYS_BOOT
-capability is required.
-.SH CONFORMING TO
-.BR reboot ()
-is Linux-specific,
-and should not be used in programs intended to be portable.
-.SH SEE ALSO
-.BR kexec_load (2),
-.BR sync (2),
-.BR bootparam (7),
-.BR capabilities (7),
-.BR ctrlaltdel (8),
-.BR halt (8),
-.BR reboot (8)
-.SH COLOPHON
-This page is part of release 3.79 of the Linux
-.I man-pages
-project.
-A description of the project,
-information about reporting bugs,
-and the latest version of this page,
-can be found at
-\%http://www.kernel.org/doc/man\-pages/.
OSDN Git Service
