man/os-release.xml

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