'\" -*- coding: UTF-8 -*-
.\" Copyright (C) 1998-2003 Miquel van Smoorenburg.
.\"
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.\"{{{}}}
.\"{{{  Title
.\"*******************************************************************
.\"
.\" This file was generated with po4a. Translate the source file.
.\"
.\"*******************************************************************
.TH SHUTDOWN 8 "12 listopada 2003" "sysvinit " "Podręcznik administratora systemu Linux"
.\"}}}
.\"{{{  Name
.SH NAZWA
.\"}}}
.\"{{{  Synopsis
shutdown \- bring the system down
.SH SKŁADNIA
.\"}}}
.\"{{{  Description
\fB/sbin/shutdown\fP [\fB\-akrhPHfFncqQ\fP] [\fB\-t\fP \fIsec\fP] \fItime\fP [\fIwarning message\fP]
.SH OPIS
.\"}}}
.\"{{{  Options
\fBshutdown\fP brings the system down in a secure way.  All logged\-in users are
notified that the system is going down, and \fBlogin\fP(1) is blocked.  It is
possible to shut the system down immediately or after a specified delay.
All processes are first notified that the system is going down by the signal
\fBSIGTERM\fP.  This gives programs like \fBvi\fP(1)  the time to save the file
being edited, mail and news processing programs a chance to exit cleanly,
etc.  \fBshutdown\fP does its job by signalling the \fBinit\fP process, asking it
to change the runlevel.  Runlevel \fB0\fP is used to halt the system, runlevel
\fB6\fP is used to reboot the system, and runlevel \fB1\fP is used to put to
system into a state where administrative tasks can be performed; this is the
default if neither the \fB\-h\fP or \fB\-r\fP flag is given to \fBshutdown\fP.  To see
which actions are taken on halt or reboot see the appropriate entries for
these runlevels in the file \fI/etc/inittab\fP.
.SH OPCJE
.\"{{{  -a
.IP \fB\-a\fP
.\"}}}
.\"{{{  -k
Use \fI/etc/shutdown.allow\fP.
.IP \fB\-k\fP
.\"}}}
.\"{{{  -r
Don't really shutdown; only send the warning messages to everybody.
.IP \fB\-r\fP
.\"}}}
.\"{{{  -h
Przeładowuje (ang. reboot) po wyłączeniu systemu.
.IP \fB\-h\fP
.\"}}}
.\"{{{  -P
Halt or power off after shutdown. Usually used with the \fB\-P\fP or \fB\-H\fP
flags, depending on whether we want to poweroff or simply stop the operating
system.
.IP \fB\-P\fP
.\"}}}
.\"{{{  -H
Modifier to the \fB\-h\fP flag. Halt action is to turn off the power.  Must be
used with the \fB\-h\fP flag.
.IP \fB\-H\fP
.\"}}}
.\"{{{  -f
Modifier to the \fB\-h\fP flag.  Halt action is to halt or drop into boot
monitor on systems that support it.  Must be used with the \fB\-h\fP flag.
Halting is often used to run through the shutdown process and leave output
on the screen for debugging purposes. Or when the user wants the OS to stop,
but leave the power on. To power off at the end of the shutdown sequence use
the \fB\-P\fP modifier instead.
.IP \fB\-f\fP
.\"}}}
.\"{{{  -F
Skip \fBfsck\fP(8) on reboot.
.IP \fB\-F\fP
.\"}}}
.\"{{{  -n
Force \fBfsck\fP(8) on reboot.
.IP \fB\-n\fP
.\"}}}
.\"{{{  -c
[DEPRECATED] Don't call \fBinit\fP(8) to do the shutdown but do it ourself.
The use of this option is discouraged, and its results are not always what
you'd expect.
.IP \fB\-c\fP
.\"{{{  -q
Cancel a waiting shutdown. (\fBshutdown now\fP is no longer waiting.) With this
option it is of course not possible to give the time argument, but you can
enter explanatory message arguments on the command line that will be sent to
all users.
.IP \fB\-q\fP
.\"{{{  -Q
Reduce the number of warnings \fBshutdown\fP displays. Usually \fBshutdown\fP
displays warnings every 15 minutes and then every minute in the last 10
minutes of the countdown until \fItime\fP is reached. When \fB\-q\fP is specified
\fBshutdown\fP only warns at 60 minute intervals, at the 10 minute mark, at the
5 minute mark, and when the shutdown process actually happens.
.IP \fB\-Q\fP
.\"}}}
.\"{{{  -t sec
Silence warnings prior to shutting down. Usually \fBshutdown\fP displays
warnings every 15 minutes and then every minute in the last 10 minutes of
the countdown until \fItime\fP is reached. When \fB\-Q\fP is specified \fBshutdown\fP
only warns when the shutdown process actually happens. All other warning
intervals are suppressed.
.IP "\fB\-t\fP \fIsec\fP"
.\"}}}
.\"{{{  time
Tell \fBinit\fP(8) to wait \fIsec\fP seconds between sending all processes the
warning (\fBSIGTERM\fP) and the kill signal (\fBSIGKILL\fP), before changing to
another runlevel.  The default time, if no value is specified, between these
two signals is three seconds. Warning: when \fBshutdown\fP calls \fBinit\fP(8) to
perform the shutdown (the default behavior), \fBinit\fP(8) checks to see if all
processes have terminated and will stop waiting early once its children have
all terminated.  When \fBshutdown\fP is called with the \fB\-n\fP flag, it waits
the full time specified (or three seconds) even if all other processes have
terminated.
.IP \fItime\fP
.\"}}}
.\"{{{  warning-message
When to shutdown.  If a \fItime\fP is given then the \fBshutdown\fP command will
not exit but instead count down until reboot.
.IP "\fIwarning message\fP"
.\"}}}
Message to send to all users.
.PP
The \fItime\fP argument can have different formats.  First, it can be an
absolute time in the format \fIhh:mm\fP, in which \fIhh\fP is the hour (1 or 2
digits) and \fImm\fP is the minute of the hour (in two digits).  Second, it can
be in the format \fB+\fP\fIm\fP, in which \fIm\fP is the number of minutes to wait.
Third, it can be in the format \fB+\fP\fIhh:mm\fP, in which \fIhh:mm\fP is the number
of hours and minutes to wait.  The word \fBnow\fP is an alias for \fB+0\fP.
.PP
If \fBshutdown\fP is called with a delay, it will create the advisory file
\fI/run/nologin\fP which causes programs such as \fBlogin\fP(1) to not allow new
user logins. This file is created five minutes before the shutdown sequence
starts. \fBshutdown\fP removes this file if it is stopped before it can signal
init (i.e. it is cancelled or something goes wrong).  It also removes it
before calling \fBinit\fP(8) to change the runlevel.
.PP
The \fB\-f\fP flag means `reboot fast'.  This only creates an advisory file
\fI/fastboot\fP which can be tested by the system when it comes up again.  The
boot rc file can test if this file is present, and decide not to run
\fBfsck\fP(8) since the system has been shut down in the proper way.  After
that, the boot process should remove \fI/fastboot\fP.
.PP
The \fB\-F\fP flag means `force fsck'.  This only creates an advisory file
\fI/forcefsck\fP which can be tested by the system when it comes up again.  The
boot rc file can test if this file is present, and decide to run \fBfsck\fP(8)
with a special `force' flag so that even properly unmounted file systems get
checked.  After that, the boot process should remove \fI/forcefsck\fP.
.PP
.\"}}}
.\"{{{  Files
The \fB\-n\fP flag causes \fBshutdown\fP not to call \fBinit\fP(8), but to kill all
running processes itself.  \fBshutdown\fP will then turn off quota, accounting,
and swapping and unmount all file systems.
.SH "ACCESS CONTROL"
\fBshutdown\fP can be called from \fBinit\fP(8) when the magic keys
\fBCTRL\-ALT\-DEL\fP are pressed, by creating an appropriate entry in
\fI/etc/inittab\fP. This means that everyone who has physical access to the
console keyboard can shut the system down. To prevent this, \fBshutdown\fP can
check to see if an authorized user is logged in on one of the virtual
consoles. If \fBshutdown\fP is called with the \fB\-a\fP argument (add this to the
invocation of shutdown in \fI/etc/inittab\fP), it checks to see if the file
\fI/etc/shutdown.allow\fP is present.  It then compares the login names in that
file with the list of people that are logged in on a virtual console (from
\fI/var/run/utmp\fP). Only if one of those authorized users \fBor root\fP is
logged in, it will proceed. Otherwise it will write the message
.sp 1
.nf
\fBshutdown: no authorized users logged in\fP
.fi
.sp 1
to the (physical) system console. The format of \fI/etc/shutdown.allow\fP is
one user name per line. Empty lines and comment lines (prefixed by a \fB#\fP)
are allowed. Currently there is a limit of 32 users in this file.
.sp 1
Note that if \fI/etc/shutdown.allow\fP is not present, the \fB\-a\fP argument is
ignored.
.SH "HALT OR POWEROFF"
The \fB\-H\fP option just sets the \fBinit\fP environment variable \fBINIT_HALT\fP to
\fBHALT\fP, and the \fB\-P\fP option just sets that variable to \fBPOWEROFF\fP. The
script (usually \fI/etc/init.d/halt\fP) that calls the \fBhalt\fP(8) program as
the last thing in the shutting down sequence should check this environment
variable and call the \fBhalt\fP(8) program with the right options for these
options to actually have any effect.
.SH PLIKI
.nf
/fastboot
/etc/inittab
/etc/init.d/halt
/etc/init.d/reboot
/etc/shutdown.allow
.fi
.\"}}}
.SH UWAGI
A lot of users forget to give the \fItime\fP argument and are then puzzled by
the error message \fBshutdown\fP produces. The \fItime\fP argument is mandatory;
in 90 percent of all cases this argument will be the word \fBnow\fP.
.PP
\fBinit\fP(8) can only capture CTRL\-ALT\-DEL and start \fBshutdown\fP in console
mode.  If the system is running the X window System, the X server processes
all key strokes. Some X11 environments make it possible to capture
CTRL\-ALT\-DEL, but what exactly is done with that event depends on that
environment.
.PP
.\"{{{  Author
\fBshutdown\fP wasn't designed to be run setuid. \fI/etc/shutdown.allow\fP is not
used to find out who is executing shutdown, it ONLY checks who is currently
logged in on (one of the) console(s).
.SH AUTOR
.\"}}}
.\"{{{  See also
.MT miquels@\:cistron\:.nl
Miquel van Smoorenburg
.ME
.SH "ZOBACZ TAKŻE"
\fBfsck\fP(8), \fBinit\fP(8), \fBhalt\fP(8), \fBpoweroff\fP(8), \fBreboot\fP(8)
.\"}}}