.\" 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.
.\"
.\" 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 2010-10-31 "Linux" "Linux Programmer's Manual"
+.TH REBOOT 2 2015-02-01 "Linux" "Linux Programmer's Manual"
.SH NAME
reboot \- reboot or enable/disable Ctrl-Alt-Del
.SH SYNOPSIS
and since 2.5.71 also
.B LINUX_REBOOT_MAGIC2C
(that is, 537993216)
-are permitted as value for
+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_DISABLE_CAD, 0).
+.RB ( RB_DISABLE_CAD ,
+0).
CAD is disabled.
This means that the CAD keystroke will cause a
.B SIGINT
proper action (maybe: kill all processes, sync, reboot).
.TP
.B LINUX_REBOOT_CMD_CAD_ON
-(RB_ENABLE_CAD, 0x89abcdef).
+.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_HALT_SYSTEM, 0xcdef0123; since 1.1.76).
+.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 " (since Linux 2.6.13)"
+.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 only available if the kernel was configured with
+This option is available only if the kernel was configured with
.BR CONFIG_KEXEC .
.TP
.B LINUX_REBOOT_CMD_POWER_OFF
-(0x4321fedc; since 2.1.30).
+.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
data will be lost.
.TP
.B LINUX_REBOOT_CMD_RESTART
-(RB_AUTOBOOT, 0x1234567).
+.RB ( RB_AUTOBOOT ,
+0x1234567).
The message "Restarting system." is printed, and a default
restart is performed immediately.
If not preceded by a
data will be lost.
.TP
.B LINUX_REBOOT_CMD_RESTART2
-(0xa1b2c3d4; since 2.1.30).
+(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 )
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 ().
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.
-.SH "RETURN VALUE"
+.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,
.SH ERRORS
.TP
.B EFAULT
-Problem with getting userspace data under
+Problem with getting user-space data under
.BR LINUX_REBOOT_CMD_RESTART2 .
.TP
.B EINVAL
the
.B CAP_SYS_BOOT
capability is required.
-.SH "CONFORMING TO"
+.SH CONFORMING TO
.BR reboot ()
is Linux-specific,
and should not be used in programs intended to be portable.
-.SH "SEE ALSO"
+.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
