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shutdown(8) [linux man page]

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

NAME
shutdown - bring the system down SYNOPSIS
shutdown [OPTION]... TIME [MESSAGE] DESCRIPTION
shutdown arranges for the system to be brought down in a safe way. All logged-in users are notified that the system is going down and, within the last five minutes of TIME, new logins are prevented. TIME may have different formats, the most common is simply the word 'now' which will bring the system down immediately. Other valid for- mats are +m, where m is the number of minutes to wait until shutting down and hh:mm which specifies the time on the 24hr clock. Once TIME has elapsed, shutdown sends a request to the init(8) daemon to bring the system down into the appropriate runlevel. This is performed by emitting the runlevel(7) event, which includes the new runlevel in the RUNLEVEL environment variable as well as the previous runlevel (obtained from the environment or from /var/run/utmp) in the PREVLEVEL variable. An additional INIT_HALT variable may be set, this will contain the value HALT when bringing the system down for halt and POWEROFF when bringing the system down for power off. OPTIONS
-r Requests that the system be rebooted after it has been brought down. -h Requests that the system be either halted or powered off after it has been brought down, with the choice as to which left up to the system. -H Requests that the system be halted after it has been brought down. -P Requests that the system be powered off after it has been brought down. -c Cancels a running shutdown. TIME is not specified with this option, the first argument is MESSAGE. -k Only send out the warning messages and disable logins, do not actually bring the system down. ENVIRONMENT
RUNLEVEL shutdown 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 new runlevel. /var/log/wtmp A new runlevel record will be appended to this file for the new runlevel. NOTES
The Upstart init(8) daemon does not keep track of runlevels itself, instead they are implemented entirely by its userspace tools. See runlevel(7) for more details. 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
runlevel(7) init(8) telinit(8) reboot(8) Upstart 2009-07-09 shutdown(8)

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

NAME
telinit - change system runlevel SYNOPSIS
telinit [OPTION]... RUNLEVEL DESCRIPTION
telinit may be used to change the system runlevel. The RUNLEVEL argument should be one of the multi-user runlevels 2-5, 0 to halt the system, 6 to reboot the system or 1 to bring the system down into single-user mode. Normally you would use the shutdown(8) tool to halt or reboot the system, or to bring it down to single-user mode. RUNLEVEL may also be S or s which will place the system directly into single-user mode without actually stopping processes first, you prob- ably won't want that. The runlevel is changed by emitting the runlevel(7) event, which includes the new runlevel in the RUNLEVEL environment variable as well as the previous runlevel (obtained from the environment or from /var/run/utmp) in the PREVLEVEL variable. telinit will write the new runlevel to /var/run/utmp and append a new entry to /var/log/wtmp. Other commands telinit may be also used to send basic commands to the init(8) daemon for compatibility with System V. These are: Q or q to request that init(8) reload its configuration. This is rarely necessary since Upstart watches its configuration with inotify(7) and is deprecated by the initctl(8) reload-configuration command. U or u to request that the init(8) daemon re-execute itself. This is not recommended since Upstart is currently unable to preserve its state, but is necessary when upgrading system libraries. OPTIONS
-e KEY=VALUE This specifies an additional environment variable to be included in the event along with RUNLEVEL and PREVLEVEL. ENVIRONMENT
RUNLEVEL telinit 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 new runlevel. /var/log/wtmp A new runlevel record will be appended to this file for the new runlevel. NOTES
The Upstart init(8) daemon does not keep track of runlevels itself, instead they are implemented entirely by its userspace tools. See runlevel(7) for more details. 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
runlevel(7) init(8) initctl(8) shutdown(8) runlevel(8) Upstart 2009-07-09 telinit(8)
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