man/runlevel.xml

   1 <?xml version='1.0'?> <!--*-nxml-*-->
   2 <!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
   3         "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
   4
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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
  62                 and current SysV runlevel if they are known.</para>
  63
  64                 <para>The two runlevel characters are separated by a
  65                 single space character. If a runlevel cannot be
  66                 determined, N is printed instead. If neither can be
  67                 determined, the word "unknown" is printed.</para>
  68
  69                 <para>Unless overridden in the environment, this will
  70                 check the utmp database for recent runlevel
  71                 changes.</para>
  72         </refsect1>
  73
  74         <refsect1>
  75                 <title>Options</title>
  76
  77                 <para>The following option is understood:</para>
  78
  79                 <variablelist>
  80                         <varlistentry>
  81                                 <term><option>--help</option></term>
  82
  83                                 <xi:include href="standard-options.xml" xpointer="help-text" />
  84                         </varlistentry>
  85                 </variablelist>
  86
  87         </refsect1>
  88
  89         <refsect1>
  90                 <title>Exit status</title>
  91
  92                 <para>If one or both runlevels could be determined, 0
  93                 is returned, a non-zero failure code otherwise.</para>
  94
  95         </refsect1>
  96
  97         <refsect1>
  98                 <title>Environment</title>
  99
 100                 <variablelist class='environment-variables'>
 101                         <varlistentry>
 102                                 <term><varname>$RUNLEVEL</varname></term>
 103
 104                                 <listitem><para>If
 105                                 <varname>$RUNLEVEL</varname> is set,
 106                                 <command>runlevel</command> will print
 107                                 this value as current runlevel and
 108                                 ignore utmp.</para></listitem>
 109                         </varlistentry>
 110
 111                         <varlistentry>
 112                                 <term><varname>$PREVLEVEL</varname></term>
 113
 114                                 <listitem><para>If
 115                                 <varname>$PREVLEVEL</varname> is set,
 116                                 <command>runlevel</command> will print
 117                                 this value as previous runlevel and
 118                                 ignore utmp.</para></listitem>
 119                         </varlistentry>
 120                 </variablelist>
 121         </refsect1>
 122
 123         <refsect1>
 124                 <title>Files</title>
 125
 126                 <variablelist>
 127                         <varlistentry>
 128                                 <term><filename>/var/run/utmp</filename></term>
 129
 130                                 <listitem><para>The utmp database
 131                                 <command>runlevel</command> reads the
 132                                 previous and current runlevel
 133                                 from.</para></listitem>
 134
 135                         </varlistentry>
 136                 </variablelist>
 137         </refsect1>
 138
 139         <refsect1>
 140                 <title>Notes</title>
 141
 142                 <para>This is a legacy command available for compatibility
 143                 only. It should not be used anymore, as the concept of
 144                 runlevels is obsolete.</para>
 145         </refsect1>
 146
 147         <refsect1>
 148                 <title>See Also</title>
 149                 <para>
 150                         <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 151                         <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>
 152                 </para>
 153         </refsect1>
 154
 155 </refentry>