linux man page for reboot

reboot(8)						      System Manager's Manual							 reboot(8)

NAME
       reboot, halt, poweroff - reboot or stop the system

SYNOPSIS
       reboot [OPTION]...

       halt [OPTION]...

       poweroff [OPTION]...

DESCRIPTION
       These programs allow a system administrator to reboot, halt or poweroff the system.

       When  called  with  --force or when in runlevel 0 or 6, this tool invokes the reboot(2) system call itself and directly reboots the system.
       Otherwise this simply invokes the shutdown(8) tool with the appropriate arguments.

       Before invoking reboot(2), a shutdown time record is first written to /var/log/wtmp

OPTIONS
       -f, --force
	      Does not invoke shutdown(8) and instead performs the actual action you would expect from the name.

       -p, --poweroff
	      Instructs the halt command to instead behave as poweroff.

       -w, --wtmp-only
	      Does not call shutdown(8) or the reboot(2) system call and instead only writes the shutdown record to /var/log/wtmp

       --verbose
	      Outputs slightly more verbose messages when rebooting, useful for debugging problems with shutdown.

ENVIRONMENT
       RUNLEVEL
	      reboot will read the current runlevel from this environment variable if set in preference to reading from /var/run/utmp

FILES
       /var/run/utmp
	      Where the current runlevel will be read from; this file will also be updated with the runlevel record being replaced by  a  shutdown
	      time record.

       /var/log/wtmp
	      A new runlevel record for the shutdown time will be appended to this file.

AUTHOR
       Written by Scott James Remnant <scott@netsplit.com>

REPORTING BUGS
       Report bugs at <https://launchpad.net/upstart/+bugs>

COPYRIGHT
       Copyright (C) 2009 Canonical Ltd.
       This is free software; see the source for copying conditions.  There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICU-
       LAR PURPOSE.

SEE ALSO
       shutdown(8) telinit(8) runlevel(8)

Upstart 							    2009-07-09								 reboot(8)