man/environment.d.xml

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