man/environment.d.xml

   1 <?xml version="1.0"?>
   2 <!--*-nxml-*-->
   3 <!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN"
   4   "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
   5 <!--
   6   SPDX-License-Identifier: LGPL-2.1+
   7
   8   Copyright © 2016 Red Hat, Inc.
   9 -->
  10 <refentry id="environment.d" conditional='ENABLE_ENVIRONMENT_D'
  11     xmlns:xi="http://www.w3.org/2001/XInclude">
  12
  13   <refentryinfo>
  14     <title>environment.d</title>
  15     <productname>systemd</productname>
  16   </refentryinfo>
  17
  18   <refmeta>
  19     <refentrytitle>environment.d</refentrytitle>
  20     <manvolnum>5</manvolnum>
  21   </refmeta>
  22
  23   <refnamediv>
  24     <refname>environment.d</refname>
  25     <refpurpose>Definition of user session environment</refpurpose>
  26   </refnamediv>
  27
  28   <refsynopsisdiv>
  29     <para><filename>~/.config/environment.d/*.conf</filename></para>
  30     <para><filename>/etc/environment.d/*.conf</filename></para>
  31     <para><filename>/run/environment.d/*.conf</filename></para>
  32     <para><filename>/usr/lib/environment.d/*.conf</filename></para>
  33     <para><filename>/etc/environment</filename></para>
  34   </refsynopsisdiv>
  35
  36   <refsect1>
  37     <title>Description</title>
  38
  39     <para>The <filename>environment.d</filename> directories contain a list of "global" environment
  40     variable assignments for the user environment.
  41     <citerefentry><refentrytitle>systemd-environment-d-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>
  42     parses them and updates the environment exported by the systemd user instance to the services it
  43     starts.</para>
  44
  45     <para>It is recommended to use numerical prefixes for file names to simplify ordering.</para>
  46
  47     <para>For backwards compatibility, a symlink to <filename>/etc/environment</filename> is
  48     installed, so this file is also parsed.</para>
  49   </refsect1>
  50
  51   <xi:include href="standard-conf.xml" xpointer="confd" />
  52
  53   <refsect1>
  54     <title>Configuration Format</title>
  55
  56     <para>The configuration files contain a list of
  57     <literal><replaceable>KEY</replaceable>=<replaceable>VALUE</replaceable></literal> environment
  58     variable assignments, separated by newlines. The right hand side of these assignments may
  59     reference previously defined environment variables, using the <literal>${OTHER_KEY}</literal>
  60     and <literal>$OTHER_KEY</literal> format. It is also possible to use
  61
  62     <literal>${<replaceable>FOO</replaceable>:-<replaceable>DEFAULT_VALUE</replaceable>}</literal>
  63     to expand in the same way as <literal>${<replaceable>FOO</replaceable>}</literal> unless the
  64     expansion would be empty, in which case it expands to <replaceable>DEFAULT_VALUE</replaceable>,
  65     and use
  66     <literal>${<replaceable>FOO</replaceable>:+<replaceable>ALTERNATE_VALUE</replaceable>}</literal>
  67     to expand to <replaceable>ALTERNATE_VALUE</replaceable> as long as
  68     <literal>${<replaceable>FOO</replaceable>}</literal> would have expanded to a non-empty value.
  69     No other elements of shell syntax are supported.</para>
  70
  71     <para>Each <replaceable>KEY</replaceable> must be a valid variable name. Empty lines
  72     and lines beginning with the comment character <literal>#</literal> are ignored.</para>
  73
  74     <refsect2>
  75       <title>Example</title>
  76       <example>
  77         <title>Setup environment to allow access to a program installed in
  78         <filename noindex='true'>/opt/foo</filename></title>
  79
  80         <para><filename>/etc/environment.d/60-foo.conf</filename>:
  81         </para>
  82         <programlisting>
  83         FOO_DEBUG=force-software-gl,log-verbose
  84         PATH=/opt/foo/bin:$PATH
  85         LD_LIBRARY_PATH=/opt/foo/lib${LD_LIBRARY_PATH:+:$LD_LIBRARY_PATH}
  86         XDG_DATA_DIRS=/opt/foo/share:${XDG_DATA_DIRS:-/usr/local/share/:/usr/share/}
  87         </programlisting>
  88       </example>
  89     </refsect2>
  90   </refsect1>
  91
  92   <refsect1>
  93     <title>See Also</title>
  94     <para>
  95       <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
  96       <citerefentry><refentrytitle>systemd-environment-d-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
  97       <citerefentry><refentrytitle>systemd.environment-generator</refentrytitle><manvolnum>7</manvolnum></citerefentry>
  98     </para>
  99   </refsect1>
 100
 101 </refentry>