man/runlevel.xml

   1 <?xml version='1.0'?> <!--*-nxml-*-->
   2 <!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
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   8   Copyright 2010 Lennart Poettering
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  23
  24 <refentry id="runlevel">
  25
  26         <refentryinfo>
  27                 <title>runlevel</title>
  28                 <productname>systemd</productname>
  29
  30                 <authorgroup>
  31                         <author>
  32                                 <contrib>Developer</contrib>
  33                                 <firstname>Lennart</firstname>
  34                                 <surname>Poettering</surname>
  35                                 <email>lennart@poettering.net</email>
  36                         </author>
  37                 </authorgroup>
  38         </refentryinfo>
  39
  40         <refmeta>
  41                 <refentrytitle>runlevel</refentrytitle>
  42                 <manvolnum>8</manvolnum>
  43         </refmeta>
  44
  45         <refnamediv>
  46                 <refname>runlevel</refname>
  47                 <refpurpose>Print previous and current SysV runlevel</refpurpose>
  48         </refnamediv>
  49
  50         <refsynopsisdiv>
  51                 <cmdsynopsis>
  52                         <command>runlevel <arg choice="opt" rep="repeat">options</arg></command>
  53                 </cmdsynopsis>
  54         </refsynopsisdiv>
  55
  56         <refsect1>
  57                 <title>Description</title>
  58
  59                 <para><command>runlevel</command> prints the previous
  60                 and current SysV runlevel if they are known.</para>
  61
  62                 <para>The two runlevel characters are separated by a
  63                 single space character. If a runlevel cannot be
  64                 determined, N is printed instead. If neither can be
  65                 determined, the word "unknown" is printed.</para>
  66
  67                 <para>Unless overridden in the environment, this will
  68                 check the utmp database for recent runlevel
  69                 changes.</para>
  70         </refsect1>
  71
  72         <refsect1>
  73                 <title>Options</title>
  74
  75                 <para>The following option is understood:</para>
  76
  77                 <variablelist>
  78                         <varlistentry>
  79                                 <term><option>--help</option></term>
  80
  81                                 <listitem><para>Prints a short help
  82                                 text and exits.</para></listitem>
  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
  92                 is returned, a non-zero failure code otherwise.</para>
  93
  94         </refsect1>
  95
  96         <refsect1>
  97                 <title>Environment</title>
  98
  99                 <variablelist>
 100                         <varlistentry>
 101                                 <term><varname>$RUNLEVEL</varname></term>
 102
 103                                 <listitem><para>If
 104                                 <varname>$RUNLEVEL</varname> is set,
 105                                 <command>runlevel</command> will print
 106                                 this value as current runlevel and
 107                                 ignore utmp.</para></listitem>
 108                         </varlistentry>
 109
 110                         <varlistentry>
 111                                 <term><varname>$PREVLEVEL</varname></term>
 112
 113                                 <listitem><para>If
 114                                 <varname>$PREVLEVEL</varname> is set
 115                                 <command>runlevel</command> will print
 116                                 this value as previous runlevel and
 117                                 ignore utmp.</para></listitem>
 118                         </varlistentry>
 119                 </variablelist>
 120         </refsect1>
 121
 122         <refsect1>
 123                 <title>Files</title>
 124
 125                 <variablelist>
 126                         <varlistentry>
 127                                 <term><varname>/var/run/utmp</varname></term>
 128
 129                                 <listitem><para>The utmp database
 130                                 <command>runlevel</command> reads the
 131                                 previous and current runlevel
 132                                 from.</para></listitem>
 133
 134                         </varlistentry>
 135                 </variablelist>
 136         </refsect1>
 137
 138         <refsect1>
 139                 <title>Notes</title>
 140
 141                 <para>This is a legacy command available for compatibility
 142                 only. It should not be used anymore, as the concept of
 143                 runlevels is obsolete.</para>
 144         </refsect1>
 145
 146         <refsect1>
 147                 <title>See Also</title>
 148                 <para>
 149                         <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 150                         <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>
 151                 </para>
 152         </refsect1>
 153
 154 </refentry>