man/os-release.xml

   1 <?xml version='1.0'?> <!--*-nxml-*-->
   2 <!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
   3   "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
   4
   5 <!--
   6   This file is part of systemd.
   7
   8   Copyright 2010 Lennart Poettering
   9
  10   systemd is free software; you can redistribute it and/or modify it
  11   under the terms of the GNU Lesser General Public License as published by
  12   the Free Software Foundation; either version 2.1 of the License, or
  13   (at your option) any later version.
  14
  15   systemd is distributed in the hope that it will be useful, but
  16   WITHOUT ANY WARRANTY; without even the implied warranty of
  17   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  18   Lesser General Public License for more details.
  19
  20   You should have received a copy of the GNU Lesser General Public License
  21   along with systemd; If not, see <http://www.gnu.org/licenses/>.
  22 -->
  23
  24 <refentry id="os-release">
  25   <refentryinfo>
  26     <title>os-release</title>
  27     <productname>systemd</productname>
  28
  29     <authorgroup>
  30       <author>
  31         <contrib>Developer</contrib>
  32         <firstname>Lennart</firstname>
  33         <surname>Poettering</surname>
  34         <email>lennart@poettering.net</email>
  35       </author>
  36     </authorgroup>
  37   </refentryinfo>
  38
  39   <refmeta>
  40     <refentrytitle>os-release</refentrytitle>
  41     <manvolnum>5</manvolnum>
  42   </refmeta>
  43
  44   <refnamediv>
  45     <refname>os-release</refname>
  46     <refpurpose>Operating system identification</refpurpose>
  47   </refnamediv>
  48
  49   <refsynopsisdiv>
  50     <para><filename>/etc/os-release</filename></para>
  51     <para><filename>/usr/lib/os-release</filename></para>
  52   </refsynopsisdiv>
  53
  54   <refsect1>
  55     <title>Description</title>
  56
  57     <para>The <filename>/etc/os-release</filename> and
  58     <filename>/usr/lib/os-release</filename> files contain operating
  59     system identification data.</para>
  60
  61     <para>The basic file format of <filename>os-release</filename> is
  62     a newline-separated list of environment-like shell-compatible
  63     variable assignments. It is possible to source the configuration
  64     from shell scripts, however, beyond mere variable assignments, no
  65     shell features are supported (this means variable expansion is
  66     explicitly not supported), allowing applications to read the file
  67     without implementing a shell compatible execution engine. Variable
  68     assignment values must be enclosed in double or single quotes if
  69     they include spaces, semicolons or other special characters
  70     outside of A–Z, a–z, 0–9. Shell special characters ("$", quotes,
  71     backslash, backtick) must be escaped with backslashes, following
  72     shell style. All strings should be in UTF-8 format, and
  73     non-printable characters should not be used. It is not supported
  74     to concatenate multiple individually quoted strings. Lines
  75     beginning with "#" shall be ignored as comments.</para>
  76
  77     <para>The file <filename>/etc/os-release</filename> takes
  78     precedence over <filename>/usr/lib/os-release</filename>.
  79     Applications should check for the former, and exclusively use its
  80     data if it exists, and only fall back to
  81     <filename>/usr/lib/os-release</filename> if it is missing.
  82     Applications should not read data from both files at the same
  83     time. <filename>/usr/lib/os-release</filename> is the recommended
  84     place to store OS release information as part of vendor trees.
  85     <filename>/etc/os-release</filename> should be a relative symlink
  86     to <filename>/usr/lib/os-release</filename>, to provide
  87     compatibility with applications only looking at
  88     <filename>/etc</filename>. A relative symlink instead of an
  89     absolute symlink is necessary to avoid breaking the link in a
  90     chroot or initrd environment such as dracut.</para>
  91
  92     <para><filename>os-release</filename> contains data that is
  93     defined by the operating system vendor and should generally not be
  94     changed by the administrator.</para>
  95
  96     <para>As this file only encodes names and identifiers it should
  97     not be localized.</para>
  98
  99     <para>The <filename>/etc/os-release</filename> and
 100     <filename>/usr/lib/os-release</filename> files might be symlinks
 101     to other files, but it is important that the file is available
 102     from earliest boot on, and hence must be located on the root file
 103     system.</para>
 104
 105     <para>For a longer rationale for <filename>os-release</filename>
 106     please refer to the <ulink
 107     url="http://0pointer.de/blog/projects/os-release">Announcement of <filename>/etc/os-release</filename></ulink>.</para>
 108   </refsect1>
 109
 110   <refsect1>
 111     <title>Options</title>
 112
 113     <para>The following OS identifications parameters may be set using
 114     <filename>os-release</filename>:</para>
 115
 116     <variablelist>
 117
 118       <varlistentry>
 119         <term><varname>NAME=</varname></term>
 120
 121         <listitem><para>A string identifying the operating system,
 122         without a version component, and suitable for presentation to
 123         the user. If not set, defaults to
 124         <literal>NAME=Linux</literal>. Example:
 125         <literal>NAME=Fedora</literal> or <literal>NAME="Debian
 126         GNU/Linux"</literal>.</para></listitem>
 127       </varlistentry>
 128
 129       <varlistentry>
 130         <term><varname>VERSION=</varname></term>
 131
 132         <listitem><para>A string identifying the operating system
 133         version, excluding any OS name information, possibly including
 134         a release code name, and suitable for presentation to the
 135         user. This field is optional. Example:
 136         <literal>VERSION=17</literal> or <literal>VERSION="17 (Beefy
 137         Miracle)"</literal>.</para></listitem>
 138       </varlistentry>
 139
 140       <varlistentry>
 141         <term><varname>ID=</varname></term>
 142
 143         <listitem><para>A lower-case string (no spaces or other
 144         characters outside of 0–9, a–z, ".", "_" and "-") identifying
 145         the operating system, excluding any version information and
 146         suitable for processing by scripts or usage in generated
 147         filenames. If not set, defaults to
 148         <literal>ID=linux</literal>. Example:
 149         <literal>ID=fedora</literal> or
 150         <literal>ID=debian</literal>.</para></listitem>
 151       </varlistentry>
 152
 153       <varlistentry>
 154         <term><varname>ID_LIKE=</varname></term>
 155
 156         <listitem><para>A space-separated list of operating system
 157         identifiers in the same syntax as the <varname>ID=</varname>
 158         setting. It should list identifiers of operating systems that
 159         are closely related to the local operating system in regards
 160         to packaging and programming interfaces, for example listing
 161         one or more OS identifiers the local OS is a derivative from.
 162         An OS should generally only list other OS identifiers it
 163         itself is a derivative of, and not any OSes that are derived
 164         from it, though symmetric relationships are possible. Build
 165         scripts and similar should check this variable if they need to
 166         identify the local operating system and the value of
 167         <varname>ID=</varname> is not recognized. Operating systems
 168         should be listed in order of how closely the local operating
 169         system relates to the listed ones, starting with the closest.
 170         This field is optional. Example: for an operating system with
 171         <literal>ID=centos</literal>, an assignment of
 172         <literal>ID_LIKE="rhel fedora"</literal> would be appropriate.
 173         For an operating system with <literal>ID=ubuntu</literal>, an
 174         assignment of <literal>ID_LIKE=debian</literal> is
 175         appropriate.</para></listitem>
 176       </varlistentry>
 177
 178       <varlistentry>
 179         <term><varname>VERSION_CODENAME=</varname></term>
 180
 181         <listitem><para>
 182         A lower-case string (no spaces or other characters outside of
 183         0–9, a–z, ".", "_" and "-") identifying the operating system
 184         release code name, excluding any OS name information or
 185         release version, and suitable for processing by scripts or
 186         usage in generated filenames. This field is optional and may
 187         not be implemented on all systems.
 188         Examples:
 189         <literal>VERSION_CODENAME=buster</literal>,
 190         <literal>VERSION_CODENAME=xenial</literal>
 191         </para></listitem>
 192       </varlistentry>
 193
 194       <varlistentry>
 195         <term><varname>VERSION_ID=</varname></term>
 196
 197         <listitem><para>A lower-case string (mostly numeric, no spaces
 198         or other characters outside of 0–9, a–z, ".", "_" and "-")
 199         identifying the operating system version, excluding any OS
 200         name information or release code name, and suitable for
 201         processing by scripts or usage in generated filenames. This
 202         field is optional. Example: <literal>VERSION_ID=17</literal>
 203         or <literal>VERSION_ID=11.04</literal>.</para></listitem>
 204       </varlistentry>
 205
 206       <varlistentry>
 207         <term><varname>PRETTY_NAME=</varname></term>
 208
 209         <listitem><para>A pretty operating system name in a format
 210         suitable for presentation to the user. May or may not contain
 211         a release code name or OS version of some kind, as suitable.
 212         If not set, defaults to
 213         <literal>PRETTY_NAME="Linux"</literal>. Example:
 214         <literal>PRETTY_NAME="Fedora 17 (Beefy
 215         Miracle)"</literal>.</para></listitem>
 216       </varlistentry>
 217
 218       <varlistentry>
 219         <term><varname>ANSI_COLOR=</varname></term>
 220
 221         <listitem><para>A suggested presentation color when showing
 222         the OS name on the console. This should be specified as string
 223         suitable for inclusion in the ESC [ m ANSI/ECMA-48 escape code
 224         for setting graphical rendition. This field is optional.
 225         Example: <literal>ANSI_COLOR="0;31"</literal> for red, or
 226         <literal>ANSI_COLOR="1;34"</literal> for light
 227         blue.</para></listitem>
 228       </varlistentry>
 229
 230       <varlistentry>
 231         <term><varname>CPE_NAME=</varname></term>
 232
 233         <listitem><para>A CPE name for the operating system, in URI
 234         binding syntax, following the
 235         <ulink url="http://scap.nist.gov/specifications/cpe/">Common
 236         Platform Enumeration Specification</ulink> as proposed by the
 237         NIST. This field is optional. Example:
 238         <literal>CPE_NAME="cpe:/o:fedoraproject:fedora:17"</literal>
 239         </para></listitem>
 240       </varlistentry>
 241
 242       <varlistentry>
 243         <term><varname>HOME_URL=</varname></term>
 244         <term><varname>SUPPORT_URL=</varname></term>
 245         <term><varname>BUG_REPORT_URL=</varname></term>
 246         <term><varname>PRIVACY_POLICY_URL=</varname></term>
 247
 248         <listitem><para>Links to resources on the Internet related the
 249         operating system. <varname>HOME_URL=</varname> should refer to
 250         the homepage of the operating system, or alternatively some
 251         homepage of the specific version of the operating system.
 252         <varname>SUPPORT_URL=</varname> should refer to the main
 253         support page for the operating system, if there is any. This
 254         is primarily intended for operating systems which vendors
 255         provide support for. <varname>BUG_REPORT_URL=</varname> should
 256         refer to the main bug reporting page for the operating system,
 257         if there is any. This is primarily intended for operating
 258         systems that rely on community QA.
 259         <varname>PRIVACY_POLICY_URL=</varname> should refer to the
 260         main privacy policy page for the operation system, if there is
 261         any. These settings are optional, and providing only some of
 262         these settings is common. These URLs are intended to be
 263         exposed in "About this system" UIs behind links with captions
 264         such as "About this Operating System", "Obtain Support",
 265         "Report a Bug", or "Privacy Policy". The values should be in
 266         <ulink url="https://tools.ietf.org/html/rfc3986">RFC3986
 267         format</ulink>, and should be <literal>http:</literal> or
 268         <literal>https:</literal> URLs, and possibly
 269         <literal>mailto:</literal> or <literal>tel:</literal>. Only
 270         one URL shall be listed in each setting. If multiple resources
 271         need to be referenced, it is recommended to provide an online
 272         landing page linking all available resources. Examples:
 273         <literal>HOME_URL="https://fedoraproject.org/"</literal> and
 274         <literal>BUG_REPORT_URL="https://bugzilla.redhat.com/"</literal></para></listitem>
 275       </varlistentry>
 276
 277       <varlistentry>
 278         <term><varname>BUILD_ID=</varname></term>
 279
 280         <listitem><para>A string uniquely identifying the system image
 281         used as the origin for a distribution (it is not updated with
 282         system updates). The field can be identical between different
 283         VERSION_IDs as BUILD_ID is an only a unique identifier to a
 284         specific version. Distributions that release each update as a
 285         new version would only need to use VERSION_ID as each build is
 286         already distinct based on the VERSION_ID. This field is
 287         optional. Example: <literal>BUILD_ID="2013-03-20.3"</literal>
 288         or <literal>BUILD_ID=201303203</literal>.
 289
 290         </para></listitem>
 291       </varlistentry>
 292
 293       <varlistentry>
 294         <term><varname>VARIANT=</varname></term>
 295
 296         <listitem><para>
 297         A string identifying a specific variant or edition of the
 298         operating system suitable for presentation to the user. This
 299         field may be used to inform the user that the configuration of
 300         this system is subject to a specific divergent set of rules or
 301         default configuration settings. This field is optional and may
 302         not be implemented on all systems.
 303         Examples:
 304         <literal>VARIANT="Server Edition"</literal>,
 305         <literal>VARIANT="Smart Refrigerator Edition"</literal>
 306         Note: this field is for display purposes only. The
 307         <varname>VARIANT_ID</varname> field should be used for making
 308         programmatic decisions.
 309         </para></listitem>
 310       </varlistentry>
 311
 312       <varlistentry>
 313         <term><varname>VARIANT_ID=</varname></term>
 314
 315         <listitem><para>
 316         A lower-case string (no spaces or other characters outside of
 317         0–9, a–z, ".", "_" and "-"), identifying a specific variant or
 318         edition of the operating system. This may be interpreted by
 319         other packages in order to determine a divergent default
 320         configuration. This field is optional and may not be
 321         implemented on all systems.
 322         Examples:
 323         <literal>VARIANT_ID=server</literal>,
 324         <literal>VARIANT_ID=embedded</literal>
 325         </para></listitem>
 326       </varlistentry>
 327
 328     </variablelist>
 329
 330     <para>If you are reading this file from C code or a shell script
 331     to determine the OS or a specific version of it, use the
 332     <varname>ID</varname> and <varname>VERSION_ID</varname> fields,
 333     possibly with <varname>ID_LIKE</varname> as fallback for
 334     <varname>ID</varname>. When looking for an OS identification
 335     string for presentation to the user use the
 336     <varname>PRETTY_NAME</varname> field.</para>
 337
 338     <para>Note that operating system vendors may choose not to provide
 339     version information, for example to accommodate for rolling
 340     releases. In this case, <varname>VERSION</varname> and
 341     <varname>VERSION_ID</varname> may be unset. Applications should
 342     not rely on these fields to be set.</para>
 343
 344     <para>Operating system vendors may extend the file
 345     format and introduce new fields. It is highly
 346     recommended to prefix new fields with an OS specific
 347     name in order to avoid name clashes. Applications
 348     reading this file must ignore unknown fields. Example:
 349     <literal>DEBIAN_BTS="debbugs://bugs.debian.org/"</literal></para>
 350   </refsect1>
 351
 352   <refsect1>
 353     <title>Example</title>
 354
 355     <programlisting>NAME=Fedora
 356 VERSION="17 (Beefy Miracle)"
 357 ID=fedora
 358 VERSION_ID=17
 359 PRETTY_NAME="Fedora 17 (Beefy Miracle)"
 360 ANSI_COLOR="0;34"
 361 CPE_NAME="cpe:/o:fedoraproject:fedora:17"
 362 HOME_URL="https://fedoraproject.org/"
 363 BUG_REPORT_URL="https://bugzilla.redhat.com/"</programlisting>
 364   </refsect1>
 365
 366   <refsect1>
 367       <title>See Also</title>
 368       <para>
 369         <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 370         <citerefentry project='die-net'><refentrytitle>lsb_release</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 371         <citerefentry><refentrytitle>hostname</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
 372         <citerefentry><refentrytitle>machine-id</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
 373         <citerefentry><refentrytitle>machine-info</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 374       </para>
 375   </refsect1>
 376
 377 </refentry>