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e17fb729 1<?xml version='1.0'?> <!--*-nxml-*-->
3a54a157 2<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN"
12b42c76 3 "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
db9ecf05 4<!-- SPDX-License-Identifier: LGPL-2.1-or-later -->
e17fb729 5
e839ebe5 6<refentry id="os-release" xmlns:xi="http://www.w3.org/2001/XInclude">
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7 <refentryinfo>
8 <title>os-release</title>
9 <productname>systemd</productname>
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10 </refentryinfo>
11
12 <refmeta>
13 <refentrytitle>os-release</refentrytitle>
14 <manvolnum>5</manvolnum>
15 </refmeta>
16
17 <refnamediv>
18 <refname>os-release</refname>
c0527e1f 19 <refname>initrd-release</refname>
9c8b6eaa 20 <refname>extension-release</refname>
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21 <refpurpose>Operating system identification</refpurpose>
22 </refnamediv>
23
24 <refsynopsisdiv>
25 <para><filename>/etc/os-release</filename></para>
26 <para><filename>/usr/lib/os-release</filename></para>
c0527e1f 27 <para><filename>/etc/initrd-release</filename></para>
9c8b6eaa 28 <para><filename>/usr/lib/extension-release.d/extension-release.<replaceable>IMAGE</replaceable></filename></para>
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29 </refsynopsisdiv>
30
31 <refsect1>
32 <title>Description</title>
33
34 <para>The <filename>/etc/os-release</filename> and
35 <filename>/usr/lib/os-release</filename> files contain operating
36 system identification data.</para>
37
49fddcd3 38 <para>The format of <filename>os-release</filename> is a newline-separated list of
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39 environment-like shell-compatible variable assignments. It is possible to source the configuration from
40 Bourne shell scripts, however, beyond mere variable assignments, no shell features are supported (this
41 means variable expansion is explicitly not supported), allowing applications to read the file without
42 implementing a shell compatible execution engine. Variable assignment values must be enclosed in double
43 or single quotes if they include spaces, semicolons or other special characters outside of A–Z, a–z,
44 0–9. (Assignments that do not include these special characters may be enclosed in quotes too, but this is
45 optional.) Shell special characters ("$", quotes, backslash, backtick) must be escaped with backslashes,
46 following shell style. All strings should be in UTF-8 encoding, and non-printable characters should not
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47 be used. Concatenation of multiple individually quoted strings is not supported. Lines beginning with "#"
48 are treated as comments. Blank lines are permitted and ignored.</para>
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49
50 <para>The file <filename>/etc/os-release</filename> takes
51 precedence over <filename>/usr/lib/os-release</filename>.
52 Applications should check for the former, and exclusively use its
53 data if it exists, and only fall back to
54 <filename>/usr/lib/os-release</filename> if it is missing.
55 Applications should not read data from both files at the same
56 time. <filename>/usr/lib/os-release</filename> is the recommended
57 place to store OS release information as part of vendor trees.
58 <filename>/etc/os-release</filename> should be a relative symlink
59 to <filename>/usr/lib/os-release</filename>, to provide
60 compatibility with applications only looking at
3b121157 61 <filename>/etc/</filename>. A relative symlink instead of an
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62 absolute symlink is necessary to avoid breaking the link in a
63 chroot or initrd environment such as dracut.</para>
64
65 <para><filename>os-release</filename> contains data that is
66 defined by the operating system vendor and should generally not be
67 changed by the administrator.</para>
68
69 <para>As this file only encodes names and identifiers it should
70 not be localized.</para>
71
72 <para>The <filename>/etc/os-release</filename> and
73 <filename>/usr/lib/os-release</filename> files might be symlinks
74 to other files, but it is important that the file is available
75 from earliest boot on, and hence must be located on the root file
76 system.</para>
77
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78 <para><filename>os-release</filename> must not contain repeating keys. Nevertheless, readers should pick
79 the entries later in the file in case of repeats, similarly to how a shell sourcing the file would. A
80 reader may warn about repeating entries.</para>
81
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82 <para>For a longer rationale for <filename>os-release</filename>
83 please refer to the <ulink
b53c3c2d 84 url="http://0pointer.de/blog/projects/os-release">Announcement of <filename>/etc/os-release</filename></ulink>.</para>
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85
86 <refsect2>
87 <title><filename>/etc/initrd-release</filename></title>
88
89 <para>In the <ulink
0e685823 90 url="https://docs.kernel.org/admin-guide/initrd.html">initrd</ulink>,
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91 <filename>/etc/initrd-release</filename> plays the same role as <filename>os-release</filename> in the
92 main system. Additionally, the presence of that file means that the system is in the initrd phase.
93 <filename>/etc/os-release</filename> should be symlinked to <filename>/etc/initrd-release</filename>
94 (or vice versa), so programs that only look for <filename>/etc/os-release</filename> (as described
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95 above) work correctly.</para>
96
97 <para>The rest of this document that talks about <filename>os-release</filename> should be understood
98 to apply to <filename>initrd-release</filename> too.</para>
c0527e1f 99 </refsect2>
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100
101 <refsect2>
102 <title><filename>/usr/lib/extension-release.d/extension-release.<replaceable>IMAGE</replaceable></filename></title>
103
104 <para><filename>/usr/lib/extension-release.d/extension-release.<replaceable>IMAGE</replaceable></filename>
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105 plays the same role for extension images as <filename>os-release</filename> for the main system, and
106 follows the syntax and rules as described in the <ulink
107 url="https://systemd.io/PORTABLE_SERVICES">Portable Services Documentation</ulink>. The purpose of this
108 file is to identify the extension and to allow the operating system to verify that the extension image
109 matches the base OS. This is typically implemented by checking that the <varname>ID=</varname> options
110 match, and either <varname>SYSEXT_LEVEL=</varname> exists and matches too, or if it is not present,
111 <varname>VERSION_ID=</varname> exists and matches. This ensures ABI/API compatibility between the
112 layers and prevents merging of an incompatible image in an overlay.</para>
113
114 <para>In the <filename>extension-release.<replaceable>IMAGE</replaceable></filename> filename, the
115 <replaceable>IMAGE</replaceable> part must exactly match the file name of the containing image with the
116 suffix removed. In case it is not possible to guarantee that an image file name is stable and doesn't
117 change between the build and the deployment phases, it is possible to relax this check: if exactly one
118 file whose name matches <literal><filename>extension-release.*</filename></literal> is present in this
119 directory, and the file is tagged with a <varname>user.extension-release.strict</varname>
ff9412c1 120 <citerefentry project='man-pages'><refentrytitle>xattr</refentrytitle><manvolnum>7</manvolnum></citerefentry> set to the
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121 string <literal>0</literal>, it will be used instead.</para>
122
123 <para>The rest of this document that talks about <filename>os-release</filename> should be understood
124 to apply to <filename>extension-release</filename> too.</para>
9c8b6eaa 125 </refsect2>
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126 </refsect1>
127
128 <refsect1>
129 <title>Options</title>
130
131 <para>The following OS identifications parameters may be set using
132 <filename>os-release</filename>:</para>
133
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134 <refsect2>
135 <title>General information identifying the operating system</title>
136
137 <variablelist class='environment-variables'>
138 <varlistentry>
139 <term><varname>NAME=</varname></term>
140
141 <listitem><para>A string identifying the operating system, without a version component, and
142 suitable for presentation to the user. If not set, a default of <literal>NAME=Linux</literal> may
143 be used.</para>
144
145 <para>Examples: <literal>NAME=Fedora</literal>, <literal>NAME="Debian GNU/Linux"</literal>.
146 </para></listitem>
147 </varlistentry>
148
149 <varlistentry>
150 <term><varname>ID=</varname></term>
151
152 <listitem><para>A lower-case string (no spaces or other characters outside of 0–9, a–z, ".", "_"
153 and "-") identifying the operating system, excluding any version information and suitable for
154 processing by scripts or usage in generated filenames. If not set, a default of
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155 <literal>ID=linux</literal> may be used. Note that even though this string may not include
156 characters that require shell quoting, quoting may nevertheless be used.</para>
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157
158 <para>Examples: <literal>ID=fedora</literal>, <literal>ID=debian</literal>.</para></listitem>
159 </varlistentry>
160
161 <varlistentry>
162 <term><varname>ID_LIKE=</varname></term>
163
164 <listitem><para>A space-separated list of operating system identifiers in the same syntax as the
165 <varname>ID=</varname> setting. It should list identifiers of operating systems that are closely
166 related to the local operating system in regards to packaging and programming interfaces, for
167 example listing one or more OS identifiers the local OS is a derivative from. An OS should
168 generally only list other OS identifiers it itself is a derivative of, and not any OSes that are
169 derived from it, though symmetric relationships are possible. Build scripts and similar should
170 check this variable if they need to identify the local operating system and the value of
171 <varname>ID=</varname> is not recognized. Operating systems should be listed in order of how
172 closely the local operating system relates to the listed ones, starting with the closest. This
173 field is optional.</para>
174
175 <para>Examples: for an operating system with <literal>ID=centos</literal>, an assignment of
176 <literal>ID_LIKE="rhel fedora"</literal> would be appropriate. For an operating system with
177 <literal>ID=ubuntu</literal>, an assignment of <literal>ID_LIKE=debian</literal> is appropriate.
178 </para></listitem>
179 </varlistentry>
180
181 <varlistentry>
182 <term><varname>PRETTY_NAME=</varname></term>
183
184 <listitem><para>A pretty operating system name in a format suitable for presentation to the
185 user. May or may not contain a release code name or OS version of some kind, as suitable. If not
186 set, a default of <literal>PRETTY_NAME="Linux"</literal> may be used</para>
187
188 <para>Example: <literal>PRETTY_NAME="Fedora 17 (Beefy Miracle)"</literal>.</para></listitem>
189 </varlistentry>
190
191 <varlistentry>
192 <term><varname>CPE_NAME=</varname></term>
193
194 <listitem><para>A CPE name for the operating system, in URI binding syntax, following the <ulink
195 url="http://scap.nist.gov/specifications/cpe/">Common Platform Enumeration Specification</ulink> as
196 proposed by the NIST. This field is optional.</para>
197
198 <para>Example: <literal>CPE_NAME="cpe:/o:fedoraproject:fedora:17"</literal></para></listitem>
199 </varlistentry>
200
201 <varlistentry>
202 <term><varname>VARIANT=</varname></term>
203
204 <listitem><para>A string identifying a specific variant or edition of the operating system suitable
205 for presentation to the user. This field may be used to inform the user that the configuration of
206 this system is subject to a specific divergent set of rules or default configuration settings. This
207 field is optional and may not be implemented on all systems.</para>
208
209 <para>Examples: <literal>VARIANT="Server Edition"</literal>, <literal>VARIANT="Smart Refrigerator
210 Edition"</literal>.</para>
211
212 <para>Note: this field is for display purposes only. The <varname>VARIANT_ID</varname> field should
213 be used for making programmatic decisions.</para></listitem>
214 </varlistentry>
215
216 <varlistentry>
217 <term><varname>VARIANT_ID=</varname></term>
218
219 <listitem><para>A lower-case string (no spaces or other characters outside of 0–9, a–z, ".", "_" and
220 "-"), identifying a specific variant or edition of the operating system. This may be interpreted by
221 other packages in order to determine a divergent default configuration. This field is optional and
222 may not be implemented on all systems.</para>
223
224 <para>Examples: <literal>VARIANT_ID=server</literal>, <literal>VARIANT_ID=embedded</literal>.
225 </para></listitem>
226 </varlistentry>
227 </variablelist>
228 </refsect2>
229
230 <refsect2>
231 <title>Information about the version of the operating system</title>
232
233 <variablelist class='environment-variables'>
234 <varlistentry>
235 <term><varname>VERSION=</varname></term>
236
237 <listitem><para>A string identifying the operating system version, excluding any OS name
238 information, possibly including a release code name, and suitable for presentation to the
239 user. This field is optional.</para>
240
241 <para>Examples: <literal>VERSION=17</literal>, <literal>VERSION="17 (Beefy Miracle)"</literal>.
242 </para></listitem>
243 </varlistentry>
244
245 <varlistentry>
246 <term><varname>VERSION_ID=</varname></term>
247
248 <listitem><para>A lower-case string (mostly numeric, no spaces or other characters outside of 0–9,
249 a–z, ".", "_" and "-") identifying the operating system version, excluding any OS name information
250 or release code name, and suitable for processing by scripts or usage in generated filenames. This
251 field is optional.</para>
252
253 <para>Examples: <literal>VERSION_ID=17</literal>, <literal>VERSION_ID=11.04</literal>.
254 </para></listitem>
255 </varlistentry>
256
257 <varlistentry>
258 <term><varname>VERSION_CODENAME=</varname></term>
259
260 <listitem><para>A lower-case string (no spaces or other characters outside of 0–9, a–z, ".", "_"
261 and "-") identifying the operating system release code name, excluding any OS name information or
262 release version, and suitable for processing by scripts or usage in generated filenames. This field
263 is optional and may not be implemented on all systems.</para>
264
265 <para>Examples: <literal>VERSION_CODENAME=buster</literal>,
266 <literal>VERSION_CODENAME=xenial</literal>.</para></listitem>
267 </varlistentry>
268
269 <varlistentry>
270 <term><varname>BUILD_ID=</varname></term>
271
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272 <listitem><para>A string uniquely identifying the system image originally used as the installation
273 base. In most cases, <varname>VERSION_ID</varname> or
274 <varname>IMAGE_ID</varname>+<varname>IMAGE_VERSION</varname> are updated when the entire system
275 image is replaced during an update. <varname>BUILD_ID</varname> may be used in distributions where
276 the original installation image version is important: <varname>VERSION_ID</varname> would change
277 during incremental system updates, but <varname>BUILD_ID</varname> would not. This field is
278 optional.</para>
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279
280 <para>Examples: <literal>BUILD_ID="2013-03-20.3"</literal>, <literal>BUILD_ID=201303203</literal>.
281 </para></listitem>
282 </varlistentry>
283
284 <varlistentry>
285 <term><varname>IMAGE_ID=</varname></term>
286
287 <listitem><para> A lower-case string (no spaces or other characters outside of 0–9, a–z, ".", "_"
288 and "-"), identifying a specific image of the operating system. This is supposed to be used for
289 environments where OS images are prepared, built, shipped and updated as comprehensive, consistent
290 OS images. This field is optional and may not be implemented on all systems, in particularly not on
291 those that are not managed via images but put together and updated from individual packages and on
292 the local system.</para>
293
294 <para>Examples: <literal>IMAGE_ID=vendorx-cashier-system</literal>,
295 <literal>IMAGE_ID=netbook-image</literal>.</para></listitem>
296 </varlistentry>
297
298 <varlistentry>
299 <term><varname>IMAGE_VERSION=</varname></term>
300
301 <listitem><para>A lower-case string (mostly numeric, no spaces or other characters outside of 0–9,
302 a–z, ".", "_" and "-") identifying the OS image version. This is supposed to be used together with
303 <varname>IMAGE_ID</varname> described above, to discern different versions of the same image.
304 </para>
305
306 <para>Examples: <literal>IMAGE_VERSION=33</literal>, <literal>IMAGE_VERSION=47.1rc1</literal>.
307 </para></listitem>
308 </varlistentry>
309 </variablelist>
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310
311 <para>To summarize: if the image updates are built and shipped as comprehensive units,
312 <varname>IMAGE_ID</varname>+<varname>IMAGE_VERSION</varname> is the best fit. Otherwise, if updates
313 eventually completely replace previously installed contents, as in a typical binary distribution,
314 <varname>VERSION_ID</varname> should be used to identify major releases of the operating system.
315 <varname>BUILD_ID</varname> may be used instead or in addition to <varname>VERSION_ID</varname> when
316 the original system image version is important.</para>
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317 </refsect2>
318
319 <refsect2>
320 <title>Presentation information and links</title>
321
322 <variablelist class='environment-variables'>
323 <varlistentry>
324 <term><varname>HOME_URL=</varname></term>
325 <term><varname>DOCUMENTATION_URL=</varname></term>
326 <term><varname>SUPPORT_URL=</varname></term>
327 <term><varname>BUG_REPORT_URL=</varname></term>
328 <term><varname>PRIVACY_POLICY_URL=</varname></term>
329
330 <listitem><para>Links to resources on the Internet related to the operating system.
331 <varname>HOME_URL=</varname> should refer to the homepage of the operating system, or alternatively
332 some homepage of the specific version of the operating system.
333 <varname>DOCUMENTATION_URL=</varname> should refer to the main documentation page for this
334 operating system. <varname>SUPPORT_URL=</varname> should refer to the main support page for the
335 operating system, if there is any. This is primarily intended for operating systems which vendors
336 provide support for. <varname>BUG_REPORT_URL=</varname> should refer to the main bug reporting page
337 for the operating system, if there is any. This is primarily intended for operating systems that
338 rely on community QA. <varname>PRIVACY_POLICY_URL=</varname> should refer to the main privacy
339 policy page for the operating system, if there is any. These settings are optional, and providing
340 only some of these settings is common. These URLs are intended to be exposed in "About this system"
341 UIs behind links with captions such as "About this Operating System", "Obtain Support", "Report a
342 Bug", or "Privacy Policy". The values should be in <ulink
343 url="https://tools.ietf.org/html/rfc3986">RFC3986 format</ulink>, and should be
344 <literal>http:</literal> or <literal>https:</literal> URLs, and possibly <literal>mailto:</literal>
345 or <literal>tel:</literal>. Only one URL shall be listed in each setting. If multiple resources
346 need to be referenced, it is recommended to provide an online landing page linking all available
347 resources.</para>
348
349 <para>Examples: <literal>HOME_URL="https://fedoraproject.org/"</literal>,
350 <literal>BUG_REPORT_URL="https://bugzilla.redhat.com/"</literal>.</para></listitem>
351 </varlistentry>
352
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353 <varlistentry>
354 <term><varname>SUPPORT_END=</varname></term>
355
356 <listitem><para>The date at which support for this version of the OS ends. (What exactly "lack of
357 support" means varies between vendors, but generally users should assume that updates, including
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358 security fixes, will not be provided.) The value is a date in the ISO 8601 format
359 <literal>YYYY-MM-DD</literal>, and specifies the first day on which support <emphasis>is
360 not</emphasis> provided.</para>
361
362 <para>For example, <literal>SUPPORT_END=2001-01-01</literal> means that the system was supported
e1b45a75 363 until the end of the last day of the previous millennium.</para></listitem>
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364 </varlistentry>
365
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366 <varlistentry>
367 <term><varname>LOGO=</varname></term>
368
369 <listitem><para>A string, specifying the name of an icon as defined by <ulink
41d6f3bf 370 url="https://standards.freedesktop.org/icon-theme-spec/latest">freedesktop.org Icon Theme
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371 Specification</ulink>. This can be used by graphical applications to display an operating system's
372 or distributor's logo. This field is optional and may not necessarily be implemented on all
373 systems.</para>
374
375 <para>Examples: <literal>LOGO=fedora-logo</literal>, <literal>LOGO=distributor-logo-opensuse</literal>
376 </para></listitem>
377 </varlistentry>
378
379 <varlistentry>
380 <term><varname>ANSI_COLOR=</varname></term>
381
382 <listitem><para>A suggested presentation color when showing the OS name on the console. This should
383 be specified as string suitable for inclusion in the ESC [ m ANSI/ECMA-48 escape code for setting
384 graphical rendition. This field is optional.</para>
385
386 <para>Examples: <literal>ANSI_COLOR="0;31"</literal> for red, <literal>ANSI_COLOR="1;34"</literal>
387 for light blue, or <literal>ANSI_COLOR="0;38;2;60;110;180"</literal> for Fedora blue.
388 </para></listitem>
389 </varlistentry>
390 </variablelist>
391 </refsect2>
392
393 <refsect2>
394 <title>Distribution-level defaults and metadata</title>
395
396 <variablelist class='environment-variables'>
397 <varlistentry>
398 <term><varname>DEFAULT_HOSTNAME=</varname></term>
399
400 <listitem><para>A string specifying the hostname if
401 <citerefentry><refentrytitle>hostname</refentrytitle><manvolnum>5</manvolnum></citerefentry> is not
402 present and no other configuration source specifies the hostname. Must be either a single DNS label
403 (a string composed of 7-bit ASCII lower-case characters and no spaces or dots, limited to the
404 format allowed for DNS domain name labels), or a sequence of such labels separated by single dots
405 that forms a valid DNS FQDN. The hostname must be at most 64 characters, which is a Linux
406 limitation (DNS allows longer names).</para>
407
408 <para>See <citerefentry><refentrytitle>org.freedesktop.hostname1</refentrytitle><manvolnum>5</manvolnum></citerefentry>
409 for a description of how
410 <citerefentry><refentrytitle>systemd-hostnamed.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>
411 determines the fallback hostname.</para></listitem>
412 </varlistentry>
413
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414 <varlistentry>
415 <term><varname>ARCHITECTURE=</varname></term>
416 <listitem><para>A string that specifies which CPU architecture the userspace binaries require.
417 The architecture identifiers are the same as for <varname>ConditionArchitecture=</varname>
418 described in <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>.
419 The field is optional and should only be used when just single architecture is supported.
420 It may provide redundant information when used in a GPT partition with a GUID type that already
421 encodes the architecture. If this is not the case, the architecture should be specified in
422 e.g., an extension image, to prevent an incompatible host from loading it.
423 </para></listitem>
424 </varlistentry>
425
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426 <varlistentry>
427 <term><varname>SYSEXT_LEVEL=</varname></term>
428
429 <listitem><para>A lower-case string (mostly numeric, no spaces or other characters outside of 0–9,
430 a–z, ".", "_" and "-") identifying the operating system extensions support level, to indicate which
9c8b6eaa 431 extension images are supported. See <filename>/usr/lib/extension-release.d/extension-release.<replaceable>IMAGE</replaceable></filename>,
0e685823 432 <ulink url="https://docs.kernel.org/admin-guide/initrd.html">initrd</ulink> and
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433 <citerefentry><refentrytitle>systemd-sysext</refentrytitle><manvolnum>8</manvolnum></citerefentry>)
434 for more information.</para>
435
436 <para>Examples: <literal>SYSEXT_LEVEL=2</literal>, <literal>SYSEXT_LEVEL=15.14</literal>.
437 </para></listitem>
438 </varlistentry>
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439
440 <varlistentry>
441 <term><varname>SYSEXT_SCOPE=</varname></term>
442 <listitem><para>Takes a space-separated list of one or more of the strings
443 <literal>system</literal>, <literal>initrd</literal> and <literal>portable</literal>. This field is
444 only supported in <filename>extension-release.d/</filename> files and indicates what environments
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445 the system extension is applicable to: i.e. to regular systems, to initrds, or to portable service
446 images. If unspecified, <literal>SYSEXT_SCOPE=system portable</literal> is implied, i.e. any system
447 extension without this field is applicable to regular systems and to portable service environments,
448 but not to initrd environments.</para></listitem>
60c5f700 449 </varlistentry>
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450
451 <varlistentry>
452 <term><varname>PORTABLE_PREFIXES=</varname></term>
453 <listitem><para>Takes a space-separated list of one or more valid prefix match strings for the
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454 <ulink url="https://systemd.io/PORTABLE_SERVICES">Portable Services Documentation</ulink> logic.
455 This field serves two purposes: it is informational, identifying portable service images as such
456 (and thus allowing them to be distinguished from other OS images, such as bootable system images).
457 It is also used when a portable service image is attached: the specified or implied portable
458 service prefix is checked against the list specified here, to enforce restrictions how images may
459 be attached to a system.</para></listitem>
8a129c80 460 </varlistentry>
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461 </variablelist>
462 </refsect2>
463
464 <refsect2>
465 <title>Notes</title>
466
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467 <para>If you are using this file to determine the OS or a specific version of it, use the
468 <varname>ID</varname> and <varname>VERSION_ID</varname> fields, possibly with
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469 <varname>ID_LIKE</varname> as fallback for <varname>ID</varname>. When looking for an OS identification
470 string for presentation to the user use the <varname>PRETTY_NAME</varname> field.</para>
471
472 <para>Note that operating system vendors may choose not to provide version information, for example to
473 accommodate for rolling releases. In this case, <varname>VERSION</varname> and
474 <varname>VERSION_ID</varname> may be unset. Applications should not rely on these fields to be
475 set.</para>
476
477 <para>Operating system vendors may extend the file format and introduce new fields. It is highly
478 recommended to prefix new fields with an OS specific name in order to avoid name clashes. Applications
479 reading this file must ignore unknown fields.</para>
480
481 <para>Example: <literal>DEBIAN_BTS="debbugs://bugs.debian.org/"</literal>.</para>
482
483 <para>Container and sandbox runtime managers may make the host's identification data available to
484 applications by providing the host's <filename>/etc/os-release</filename> (if available, otherwise
485 <filename>/usr/lib/os-release</filename> as a fallback) as
486 <filename>/run/host/os-release</filename>.</para>
487 </refsect2>
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488 </refsect1>
489
490 <refsect1>
e839ebe5 491 <title>Examples</title>
798d3a52 492
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493 <example>
494 <title><filename>os-release</filename> file for Fedora Workstation</title>
495
496 <programlisting>NAME=Fedora
f4ff71b3 497VERSION="32 (Workstation Edition)"
e17fb729 498ID=fedora
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499VERSION_ID=32
500PRETTY_NAME="Fedora 32 (Workstation Edition)"
501ANSI_COLOR="0;38;2;60;110;180"
502LOGO=fedora-logo-icon
503CPE_NAME="cpe:/o:fedoraproject:fedora:32"
62ca938d 504HOME_URL="https://fedoraproject.org/"
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505DOCUMENTATION_URL="https://docs.fedoraproject.org/en-US/fedora/f32/system-administrators-guide/"
506SUPPORT_URL="https://fedoraproject.org/wiki/Communicating_and_getting_help"
507BUG_REPORT_URL="https://bugzilla.redhat.com/"
508REDHAT_BUGZILLA_PRODUCT="Fedora"
509REDHAT_BUGZILLA_PRODUCT_VERSION=32
510REDHAT_SUPPORT_PRODUCT="Fedora"
511REDHAT_SUPPORT_PRODUCT_VERSION=32
512PRIVACY_POLICY_URL="https://fedoraproject.org/wiki/Legal:PrivacyPolicy"
513VARIANT="Workstation Edition"
514VARIANT_ID=workstation</programlisting>
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515 </example>
516
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517 <example>
518 <title><filename>extension-release</filename> file for an extension for Fedora Workstation 32</title>
519
520 <programlisting>ID=fedora
521VERSION_ID=32</programlisting>
522 </example>
523
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524 <example>
525 <title>Reading <filename>os-release</filename> in
ff9412c1 526 <citerefentry project='man-pages'><refentrytitle>sh</refentrytitle><manvolnum>1</manvolnum></citerefentry></title>
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527
528 <programlisting><xi:include href="check-os-release.sh" parse="text" /></programlisting>
529 </example>
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530
531 <example>
532 <title>Reading <filename>os-release</filename> in
ff9412c1 533 <citerefentry project='die-net'><refentrytitle>python</refentrytitle><manvolnum>1</manvolnum></citerefentry> (versions &gt;= 3.10)</title>
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534
535 <programlisting><xi:include href="check-os-release-simple.py" parse="text" /></programlisting>
536
537 <para>See docs for <ulink url="https://docs.python.org/3/library/platform.html#platform.freedesktop_os_release">
538 <function>platform.freedesktop_os_release</function></ulink> for more details.
539 </para>
540 </example>
541
542 <example>
543 <title>Reading <filename>os-release</filename> in
ff9412c1 544 <citerefentry project='die-net'><refentrytitle>python</refentrytitle><manvolnum>1</manvolnum></citerefentry> (any version)</title>
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545
546 <programlisting><xi:include href="check-os-release.py" parse="text" /></programlisting>
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547
548 <para>Note that the above version that uses the built-in implementation is preferred
549 in most cases, and the open-coded version here is provided for reference.</para>
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550 </example>
551
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552 </refsect1>
553
554 <refsect1>
555 <title>See Also</title>
556 <para>
557 <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
3ba3a79d 558 <citerefentry project='die-net'><refentrytitle>lsb_release</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
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559 <citerefentry><refentrytitle>hostname</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
560 <citerefentry><refentrytitle>machine-id</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
561 <citerefentry><refentrytitle>machine-info</refentrytitle><manvolnum>5</manvolnum></citerefentry>
562 </para>
563 </refsect1>
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564
565</refentry>