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systemd/man/runlevel.xml
Lennart Poettering df1e020461 Revert back to /var/run at a couple of problems
This partially reverts 41a55c46ab

Some specifications we want to stay compatibility actually document
/var/run, not /run, and we should stay compatible with that. In order to
make sure our D-Bus implementation works on any system, regardless if
running systemd or not, we should always use /var/run which is the
only path mandated by the D-Bus spec.

Similar, glibc hardcodes the utmp location to /var/run, and this is
exposed in _UTMP_PATH in limits.h, hence let's stay in sync with this
public API, too.

We simply do not support systems where /var/run is not a symlink → /run.
Hence both are equivalent. Staying compatible with upstream
specifications hence weighs more than cleaning up superficial
appearance.
2014-02-26 02:47:43 +01:00

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<?xml version='1.0'?> <!--*-nxml-*-->
<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
"http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
<!--
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You should have received a copy of the GNU Lesser General Public License
along with systemd; If not, see <http://www.gnu.org/licenses/>.
-->
<refentry id="runlevel"
xmlns:xi="http://www.w3.org/2001/XInclude">
<refentryinfo>
<title>runlevel</title>
<productname>systemd</productname>
<authorgroup>
<author>
<contrib>Developer</contrib>
<firstname>Lennart</firstname>
<surname>Poettering</surname>
<email>lennart@poettering.net</email>
</author>
</authorgroup>
</refentryinfo>
<refmeta>
<refentrytitle>runlevel</refentrytitle>
<manvolnum>8</manvolnum>
</refmeta>
<refnamediv>
<refname>runlevel</refname>
<refpurpose>Print previous and current SysV runlevel</refpurpose>
</refnamediv>
<refsynopsisdiv>
<cmdsynopsis>
<command>runlevel <arg choice="opt" rep="repeat">options</arg></command>
</cmdsynopsis>
</refsynopsisdiv>
<refsect1>
<title>Description</title>
<para><command>runlevel</command> prints the previous
and current SysV runlevel if they are known.</para>
<para>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.</para>
<para>Unless overridden in the environment, this will
check the utmp database for recent runlevel
changes.</para>
</refsect1>
<refsect1>
<title>Options</title>
<para>The following option is understood:</para>
<variablelist>
<varlistentry>
<term><option>--help</option></term>
<xi:include href="standard-options.xml" xpointer="help-text" />
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>Exit status</title>
<para>If one or both runlevels could be determined, 0
is returned, a non-zero failure code otherwise.</para>
</refsect1>
<refsect1>
<title>Environment</title>
<variablelist class='environment-variables'>
<varlistentry>
<term><varname>$RUNLEVEL</varname></term>
<listitem><para>If
<varname>$RUNLEVEL</varname> is set,
<command>runlevel</command> will print
this value as current runlevel and
ignore utmp.</para></listitem>
</varlistentry>
<varlistentry>
<term><varname>$PREVLEVEL</varname></term>
<listitem><para>If
<varname>$PREVLEVEL</varname> is set,
<command>runlevel</command> will print
this value as previous runlevel and
ignore utmp.</para></listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>Files</title>
<variablelist>
<varlistentry>
<term><filename>/var/run/utmp</filename></term>
<listitem><para>The utmp database
<command>runlevel</command> reads the
previous and current runlevel
from.</para></listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>Notes</title>
<para>This is a legacy command available for compatibility
only. It should not be used anymore, as the concept of
runlevels is obsolete.</para>
</refsect1>
<refsect1>
<title>See Also</title>
<para>
<citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
<citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>
</para>
</refsect1>
</refentry>