man/systemd-backlight@.service.xml

   1 <?xml version="1.0"?>
   2 <!--*-nxml-*-->
   3 <!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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   5   This file is part of systemd.
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   7   Copyright 2013 Lennart Poettering
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  22 <refentry id="systemd-backlight@.service" conditional='ENABLE_BACKLIGHT'>
  23
  24         <refentryinfo>
  25                 <title>systemd-backlight@.service</title>
  26                 <productname>systemd</productname>
  27
  28                 <authorgroup>
  29                         <author>
  30                                 <contrib>Developer</contrib>
  31                                 <firstname>Lennart</firstname>
  32                                 <surname>Poettering</surname>
  33                                 <email>lennart@poettering.net</email>
  34                         </author>
  35                 </authorgroup>
  36         </refentryinfo>
  37
  38         <refmeta>
  39                 <refentrytitle>systemd-backlight@.service</refentrytitle>
  40                 <manvolnum>8</manvolnum>
  41         </refmeta>
  42
  43         <refnamediv>
  44                 <refname>systemd-backlight@.service</refname>
  45                 <refname>systemd-backlight</refname>
  46                 <refpurpose>Load and save the display backlight brightness at boot and shutdown</refpurpose>
  47         </refnamediv>
  48
  49         <refsynopsisdiv>
  50                 <para><filename>systemd-backlight@.service</filename></para>
  51                 <para><filename>/usr/lib/systemd/systemd-backlight</filename></para>
  52         </refsynopsisdiv>
  53
  54         <refsect1>
  55                 <title>Description</title>
  56
  57                 <para><filename>systemd-backlight@.service</filename>
  58                 is a service that restores the display backlight
  59                 brightness at early boot and saves it at shutdown. On
  60                 disk, the backlight brightness is stored in
  61                 <filename>/var/lib/systemd/backlight/</filename>.</para>
  62         </refsect1>
  63
  64         <refsect1>
  65                 <title>Kernel Command Line</title>
  66
  67                 <para><filename>systemd-backlight</filename> understands
  68                 the following kernel command line parameter:</para>
  69
  70                 <variablelist class='kernel-commandline-options'>
  71                         <varlistentry>
  72                                 <term><varname>systemd.restore_state=</varname></term>
  73
  74                                 <listitem><para>Takes a boolean
  75                                 argument. Defaults to
  76                                 <literal>1</literal>. If
  77                                 <literal>0</literal>, does not restore
  78                                 the backlight settings on boot. However,
  79                                 settings will still be stored on shutdown.
  80                                 </para></listitem>
  81                         </varlistentry>
  82                 </variablelist>
  83         </refsect1>
  84
  85         <refsect1>
  86                 <title>See Also</title>
  87                 <para>
  88                         <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>
  89                 </para>
  90         </refsect1>
  91
  92 </refentry>