systemd/man/environment.d.xml
Ray Strode af92daebc5 man: fix LD_LIBRARY_PATH example in environment.d (#5929)
The example for LD_LIBRARY_PATH in the environment.d man page is wrong.

When setting LD_LIBRARY_PATH, the new directory usually needs to be at
the front so it overrides old directories.

In the example, the colon delimiter is correctly prepended to the front, but
the actual new path is erroneously appended to the end.

This commit moves it to the front where it belongs.
2017-05-10 22:23:54 -04:00

124 lines
4.9 KiB
XML

<?xml version="1.0"?>
<!--*-nxml-*-->
<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN" "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
<!--
This file is part of systemd.
Copyright 2016 Red Hat, Inc.
Copyright 2017 Zbigniew Jędrzejewski-Szmek
systemd is free software; you can redistribute it and/or modify it
under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 2.1 of the License, or
(at your option) any later version.
systemd is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public License
along with systemd; If not, see <http://www.gnu.org/licenses/>.
-->
<refentry id="environment.d" conditional='ENABLE_ENVIRONMENT_D'
xmlns:xi="http://www.w3.org/2001/XInclude">
<refentryinfo>
<title>environment.d</title>
<productname>systemd</productname>
<authorgroup>
<author>
<contrib>Developer</contrib>
<firstname>Ray</firstname>
<surname>Strode</surname>
<email>rstrode@redhat.com</email>
</author>
</authorgroup>
</refentryinfo>
<refmeta>
<refentrytitle>environment.d</refentrytitle>
<manvolnum>5</manvolnum>
</refmeta>
<refnamediv>
<refname>environment.d</refname>
<refpurpose>Definition of user session environment</refpurpose>
</refnamediv>
<refsynopsisdiv>
<para><filename>~/.config/environment.d/*.conf</filename></para>
<para><filename>/etc/environment.d/*.conf</filename></para>
<para><filename>/run/environment.d/*.conf</filename></para>
<para><filename>/usr/lib/environment.d/*.conf</filename></para>
<para><filename>/etc/environment</filename></para>
</refsynopsisdiv>
<refsect1>
<title>Description</title>
<para>The <filename>environment.d</filename> directories contain a list of "global" environment
variable assignments for the user environment.
<citerefentry><refentrytitle>systemd-environment-d-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>
parses them and updates the environment exported by the systemd user instance to the services it
starts.</para>
<para>It is recommended to use numerical prefixes for file names to simplify ordering.</para>
<para>For backwards compatibility, a symlink to <filename>/etc/environment</filename> is
installed, so this file is also parsed.</para>
</refsect1>
<xi:include href="standard-conf.xml" xpointer="confd" />
<refsect1>
<title>Configuration Format</title>
<para>The configuration files contain a list of
<literal><replaceable>KEY</replaceable>=<replaceable>VALUE</replaceable></literal> environment
variable assignments, separated by newlines. The right hand side of these assignments may
reference previously defined environment variables, using the <literal>${OTHER_KEY}</literal>
and <literal>$OTHER_KEY</literal> format. It is also possible to use
<literal>${<replaceable>FOO</replaceable>:-<replaceable>DEFAULT_VALUE</replaceable>}</literal>
to expand in the same way as <literal>${<replaceable>FOO</replaceable>}</literal> unless the
expansion would be empty, in which case it expands to <replaceable>DEFAULT_VALUE</replaceable>,
and use
<literal>${<replaceable>FOO</replaceable>:+<replaceable>ALTERNATE_VALUE</replaceable>}</literal>
to expand to <replaceable>ALTERNATE_VALUE</replaceable> as long as
<literal>${<replaceable>FOO</replaceable>}</literal> would have expanded to a non-empty value.
No other elements of shell syntax are supported.</para>
<para>Each<replaceable>KEY</replaceable> must be a valid variable name. Empty lines
and lines beginning with the comment character <literal>#</literal> are ignored.</para>
<refsect2>
<title>Example</title>
<example>
<title>Setup environment to allow access to a program installed in
<filename noindex='true'>/opt/foo</filename></title>
<para><filename>/etc/environment.d/60-foo.conf</filename>:
</para>
<programlisting>
FOO_DEBUG=force-software-gl,log-verbose
PATH=/opt/foo/bin:$PATH
LD_LIBRARY_PATH=/opt/foo/lib${LD_LIBRARY_PATH:+:$LD_LIBRARY_PATH}
XDG_DATA_DIRS=/opt/foo/share:${XDG_DATA_DIRS:-/usr/local/share/:/usr/share/}
</programlisting>
</example>
</refsect2>
</refsect1>
<refsect1>
<title>See Also</title>
<para>
<citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
<citerefentry><refentrytitle>systemd-environment-d-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
<citerefentry><refentrytitle>systemd.environment-generator</refentrytitle><manvolnum>7</manvolnum></citerefentry>
</para>
</refsect1>
</refentry>