man/runlevel.xml

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   8   Copyright 2010 Lennart Poettering
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  23
  24 <refentry id="runlevel"
  25     xmlns:xi="http://www.w3.org/2001/XInclude"
  26     conditional="HAVE_UTMP">
  27
  28   <refentryinfo>
  29     <title>runlevel</title>
  30     <productname>systemd</productname>
  31
  32     <authorgroup>
  33       <author>
  34         <contrib>Developer</contrib>
  35         <firstname>Lennart</firstname>
  36         <surname>Poettering</surname>
  37         <email>lennart@poettering.net</email>
  38       </author>
  39     </authorgroup>
  40   </refentryinfo>
  41
  42   <refmeta>
  43     <refentrytitle>runlevel</refentrytitle>
  44     <manvolnum>8</manvolnum>
  45   </refmeta>
  46
  47   <refnamediv>
  48     <refname>runlevel</refname>
  49     <refpurpose>Print previous and current SysV runlevel</refpurpose>
  50   </refnamediv>
  51
  52   <refsynopsisdiv>
  53     <cmdsynopsis>
  54       <command>runlevel <arg choice="opt" rep="repeat">options</arg></command>
  55     </cmdsynopsis>
  56   </refsynopsisdiv>
  57
  58   <refsect1>
  59     <title>Description</title>
  60
  61     <para><command>runlevel</command> prints the previous and current
  62     SysV runlevel if they are known.</para>
  63
  64     <para>The two runlevel characters are separated by a single space
  65     character. If a runlevel cannot be determined, N is printed
  66     instead. If neither can be determined, the word "unknown" is
  67     printed.</para>
  68
  69     <para>Unless overridden in the environment, this will check the
  70     utmp database for recent runlevel changes.</para>
  71   </refsect1>
  72
  73   <refsect1>
  74     <title>Options</title>
  75
  76     <para>The following option is understood:</para>
  77
  78     <variablelist>
  79       <varlistentry>
  80         <term><option>--help</option></term>
  81
  82         <xi:include href="standard-options.xml" xpointer="help-text" />
  83       </varlistentry>
  84     </variablelist>
  85
  86   </refsect1>
  87
  88   <refsect1>
  89     <title>Exit status</title>
  90
  91     <para>If one or both runlevels could be determined, 0 is returned,
  92     a non-zero failure code otherwise.</para>
  93
  94   </refsect1>
  95
  96   <refsect1>
  97     <title>Environment</title>
  98
  99     <variablelist class='environment-variables'>
 100       <varlistentry>
 101         <term><varname>$RUNLEVEL</varname></term>
 102
 103         <listitem><para>If <varname>$RUNLEVEL</varname> is set,
 104         <command>runlevel</command> will print this value as current
 105         runlevel and ignore utmp.</para></listitem>
 106       </varlistentry>
 107
 108       <varlistentry>
 109         <term><varname>$PREVLEVEL</varname></term>
 110
 111         <listitem><para>If <varname>$PREVLEVEL</varname> is set,
 112         <command>runlevel</command> will print this value as previous
 113         runlevel and ignore utmp.</para></listitem>
 114       </varlistentry>
 115     </variablelist>
 116   </refsect1>
 117
 118   <refsect1>
 119     <title>Files</title>
 120
 121     <variablelist>
 122       <varlistentry>
 123         <term><filename>/var/run/utmp</filename></term>
 124
 125         <listitem><para>The utmp database <command>runlevel</command>
 126         reads the previous and current runlevel
 127         from.</para></listitem>
 128       </varlistentry>
 129     </variablelist>
 130   </refsect1>
 131
 132   <refsect1>
 133     <title>Notes</title>
 134
 135     <para>This is a legacy command available for compatibility only.
 136     It should not be used anymore, as the concept of runlevels is
 137     obsolete.</para>
 138   </refsect1>
 139
 140   <refsect1>
 141     <title>See Also</title>
 142     <para>
 143       <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 144       <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>
 145     </para>
 146   </refsect1>
 147
 148 </refentry>