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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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RUNLEVEL(8)                                                          runlevel                                                          RUNLEVEL(8)

NAME
runlevel - Print previous and current SysV runlevel SYNOPSIS
runlevel [options...] OVERVIEW
"Runlevels" are an obsolete way to start and stop groups of services used in SysV init. systemd provides a compatibility layer that maps runlevels to targets, and associated binaries like runlevel. Nevertheless, only one runlevel can be "active" at a given time, while systemd can activate multiple targets concurrently, so the mapping to runlevels is confusing and only approximate. Runlevels should not be used in new code, and are mostly useful as a shorthand way to refer the matching systemd targets in kernel boot parameters. Table 1. Mapping between runlevels and systemd targets +---------+-------------------+ |Runlevel | Target | +---------+-------------------+ |0 | poweroff.target | +---------+-------------------+ |1 | rescue.target | +---------+-------------------+ |2, 3, 4 | multi-user.target | +---------+-------------------+ |5 | graphical.target | +---------+-------------------+ |6 | reboot.target | +---------+-------------------+ DESCRIPTION
runlevel prints the previous and current SysV runlevel if they are known. The two runlevel characters are separated by a single space character. If a runlevel cannot be determined, N is printed instead. If neither can be determined, the word "unknown" is printed. Unless overridden in the environment, this will check the utmp database for recent runlevel changes. OPTIONS
The following option is understood: --help Print a short help text and exit. EXIT STATUS
If one or both runlevels could be determined, 0 is returned, a non-zero failure code otherwise. ENVIRONMENT
$RUNLEVEL If $RUNLEVEL is set, runlevel will print this value as current runlevel and ignore utmp. $PREVLEVEL If $PREVLEVEL is set, runlevel will print this value as previous runlevel and ignore utmp. FILES
/run/utmp The utmp database runlevel reads the previous and current runlevel from. SEE ALSO
systemd(1), systemd.target(5), systemctl(1) systemd 237 RUNLEVEL(8)

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