"http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
<!--
- This file is part of systemd.
+ SPDX-License-Identifier: LGPL-2.1+
Copyright 2010 Lennart Poettering
-
- 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="os-release">
without implementing a shell compatible execution engine. Variable
assignment values must be enclosed in double or single quotes if
they include spaces, semicolons or other special characters
- outside of A-Z, a-z, 0-9. Shell special characters ("$", quotes,
+ outside of A–Z, a–z, 0–9. Shell special characters ("$", quotes,
backslash, backtick) must be escaped with backslashes, following
shell style. All strings should be in UTF-8 format, and
non-printable characters should not be used. It is not supported
to concatenate multiple individually quoted strings. Lines
- beginning with "#" shall be ignored as comments.</para>
+ beginning with "#" shall be ignored as comments. Blank lines are
+ permitted and ignored.</para>
<para>The file <filename>/etc/os-release</filename> takes
precedence over <filename>/usr/lib/os-release</filename>.
<term><varname>ID=</varname></term>
<listitem><para>A lower-case string (no spaces or other
- characters outside of 0-9, a-z, ".", "_" and "-") identifying
+ characters outside of 0–9, a–z, ".", "_" and "-") identifying
the operating system, excluding any version information and
suitable for processing by scripts or usage in generated
filenames. If not set, defaults to
appropriate.</para></listitem>
</varlistentry>
+ <varlistentry>
+ <term><varname>VERSION_CODENAME=</varname></term>
+
+ <listitem><para>
+ A lower-case string (no spaces or other characters outside of
+ 0–9, a–z, ".", "_" and "-") identifying the operating system
+ release code name, excluding any OS name information or
+ release version, and suitable for processing by scripts or
+ usage in generated filenames. This field is optional and may
+ not be implemented on all systems.
+ Examples:
+ <literal>VERSION_CODENAME=buster</literal>,
+ <literal>VERSION_CODENAME=xenial</literal>
+ </para></listitem>
+ </varlistentry>
+
<varlistentry>
<term><varname>VERSION_ID=</varname></term>
<listitem><para>A lower-case string (mostly numeric, no spaces
- or other characters outside of 0-9, a-z, ".", "_" and "-")
+ or other characters outside of 0–9, a–z, ".", "_" and "-")
identifying the operating system version, excluding any OS
name information or release code name, and suitable for
processing by scripts or usage in generated filenames. This
<varlistentry>
<term><varname>CPE_NAME=</varname></term>
- <listitem><para>A CPE name for the operating system, following
- the <ulink url="https://cpe.mitre.org/specification/">Common
+ <listitem><para>A CPE name for the operating system, in URI
+ binding syntax, following the
+ <ulink url="http://scap.nist.gov/specifications/cpe/">Common
Platform Enumeration Specification</ulink> as proposed by the
- MITRE Corporation. This field is optional. Example:
+ NIST. This field is optional. Example:
<literal>CPE_NAME="cpe:/o:fedoraproject:fedora:17"</literal>
</para></listitem>
</varlistentry>
<listitem><para>
A lower-case string (no spaces or other characters outside of
- 0-9, a-z, ".", "_" and "-"), identifying a specific variant or
+ 0–9, a–z, ".", "_" and "-"), identifying a specific variant or
edition of the operating system. This may be interpreted by
other packages in order to determine a divergent default
configuration. This field is optional and may not be