man/environment.d.xml

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