man/environment.d.xml

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   7   This file is part of systemd.
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   9   Copyright 2016 Red Hat, Inc.
  10   Copyright 2017 Zbigniew Jędrzejewski-Szmek
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  25 <refentry id="environment.d" conditional='ENABLE_ENVIRONMENT_D'
  26     xmlns:xi="http://www.w3.org/2001/XInclude">
  27
  28   <refentryinfo>
  29     <title>environment.d</title>
  30     <productname>systemd</productname>
  31
  32     <authorgroup>
  33       <author>
  34         <contrib>Developer</contrib>
  35         <firstname>Ray</firstname>
  36         <surname>Strode</surname>
  37         <email>rstrode@redhat.com</email>
  38       </author>
  39     </authorgroup>
  40   </refentryinfo>
  41
  42   <refmeta>
  43     <refentrytitle>environment.d</refentrytitle>
  44     <manvolnum>5</manvolnum>
  45   </refmeta>
  46
  47   <refnamediv>
  48     <refname>environment.d</refname>
  49     <refpurpose>Definition of user session environment</refpurpose>
  50   </refnamediv>
  51
  52   <refsynopsisdiv>
  53     <para><filename>~/.config/environment.d/*.conf</filename></para>
  54     <para><filename>/etc/environment.d/*.conf</filename></para>
  55     <para><filename>/run/environment.d/*.conf</filename></para>
  56     <para><filename>/usr/lib/environment.d/*.conf</filename></para>
  57     <para><filename>/etc/environment</filename></para>
  58   </refsynopsisdiv>
  59
  60   <refsect1>
  61     <title>Description</title>
  62
  63     <para>The <filename>environment.d</filename> directories contain a list of "global" environment
  64     variable assignments for the user environment.
  65     <citerefentry><refentrytitle>systemd-environment-d-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>
  66     parses them and updates the environment exported by the systemd user instance to the services it
  67     starts.</para>
  68
  69     <para>It is recommended to use numerical prefixes for file names to simplify ordering.</para>
  70
  71     <para>For backwards compatibility, a symlink to <filename>/etc/environment</filename> is
  72     installed, so this file is also parsed.</para>
  73   </refsect1>
  74
  75   <xi:include href="standard-conf.xml" xpointer="confd" />
  76
  77   <refsect1>
  78     <title>Configuration Format</title>
  79
  80     <para>The configuration files contain a list of
  81     <literal><replaceable>KEY</replaceable>=<replaceable>VALUE</replaceable></literal> environment
  82     variable assignments, separated by newlines. The right hand side of these assignments may
  83     reference previously defined environment variables, using the <literal>${OTHER_KEY}</literal>
  84     and <literal>$OTHER_KEY</literal> format. It is also possible to use
  85
  86     <literal>${<replaceable>FOO</replaceable>:-<replaceable>DEFAULT_VALUE</replaceable>}</literal>
  87     to expand in the same way as <literal>${<replaceable>FOO</replaceable>}</literal> unless the
  88     expansion would be empty, in which case it expands to <replaceable>DEFAULT_VALUE</replaceable>,
  89     and use
  90     <literal>${<replaceable>FOO</replaceable>:+<replaceable>ALTERNATE_VALUE</replaceable>}</literal>
  91     to expand to <replaceable>ALTERNATE_VALUE</replaceable> as long as
  92     <literal>${<replaceable>FOO</replaceable>}</literal> would have expanded to a non-empty value.
  93     No other elements of shell syntax are supported.</para>
  94
  95     <para>Each <replaceable>KEY</replaceable> must be a valid variable name. Empty lines
  96     and lines beginning with the comment character <literal>#</literal> are ignored.</para>
  97
  98     <refsect2>
  99       <title>Example</title>
 100       <example>
 101         <title>Setup environment to allow access to a program installed in
 102         <filename noindex='true'>/opt/foo</filename></title>
 103
 104         <para><filename>/etc/environment.d/60-foo.conf</filename>:
 105         </para>
 106         <programlisting>
 107         FOO_DEBUG=force-software-gl,log-verbose
 108         PATH=/opt/foo/bin:$PATH
 109         LD_LIBRARY_PATH=/opt/foo/lib${LD_LIBRARY_PATH:+:$LD_LIBRARY_PATH}
 110         XDG_DATA_DIRS=/opt/foo/share:${XDG_DATA_DIRS:-/usr/local/share/:/usr/share/}
 111         </programlisting>
 112       </example>
 113     </refsect2>
 114   </refsect1>
 115
 116   <refsect1>
 117     <title>See Also</title>
 118     <para>
 119       <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 120       <citerefentry><refentrytitle>systemd-environment-d-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
 121       <citerefentry><refentrytitle>systemd.environment-generator</refentrytitle><manvolnum>7</manvolnum></citerefentry>
 122     </para>
 123   </refsect1>
 124
 125 </refentry>