<refsynopsisdiv>
<para><filename>/etc/os-release</filename></para>
+ <para><filename>/usr/lib/os-release</filename></para>
</refsynopsisdiv>
<refsect1>
<title>Description</title>
- <para>The <filename>/etc/os-release</filename> file
- contains operating system identification data.</para>
+ <para>The <filename>/etc/os-release</filename> and
+ <filename>/usr/lib/os-release</filename> files contain
+ operating system identification data.</para>
<para>The basic file format of
<filename>os-release</filename> is a newline-separated
(this means variable expansion is explicitly not
supported), allowing applications to read the file
without implementing a shell compatible execution
- engine. Variable assignment values should be enclosed
- in double or single quotes if they include spaces,
+ 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. All strings should be in UTF-8 format, and
- non-printable characters should not be used. If double
- or single quotes or backslashes are to be used within
- variable assignments, they should be escaped with
- backslashes, following shell style. It is not
- supported to concatenate multiple individually quoted
- strings. Lines beginning with "#" shall be ignored as
- comments.</para>
-
- <para><filename>/etc/os-release</filename> contains
- data that is defined by the operating system vendor
- and should not be changed by the administrator.</para>
+ 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>
+
+ <para>The file <filename>/etc/os-release</filename>
+ takes precedence over
+ <filename>/usr/lib/os-release</filename>. Applications
+ should check for the former, and exclusively use its
+ data if it exists, and only fall back to
+ <filename>/usr/lib/os-release</filename> if it is
+ missing. Applications should not read data from both
+ files at the same
+ time. <filename>/usr/lib/os-release</filename> is the
+ recommended place to store OS release information as
+ part of vendor trees.
+ <filename>/etc/os-release</filename> should be a
+ relative symlink to
+ <filename>/usr/lib/os-release</filename>,
+ to provide compatibility with applications only
+ looking at <filename>/etc</filename>. A relative
+ symlink instead of an absolute symlink is
+ necessary to avoid breaking the link in a chroot or
+ initrd environment such as dracut.</para>
+
+ <para><filename>os-release</filename> contains data
+ that is defined by the operating system vendor and
+ should generally not be changed by the
+ administrator.</para>
<para>As this file only encodes names and identifiers
it should not be localized.</para>
- <para>The file <filename>/etc/os-release</filename> might
- be a symlink to another file, but it is important that
+ <para>The <filename>/etc/os-release</filename> and
+ <filename>/usr/lib/os-release</filename> files might
+ be symlinks to other files, but it is important that
the file is available from earliest boot on, and hence
must be located on the root file system.</para>
<para>For a longer rationale for
- <filename>/etc/os-release</filename> please refer to
+ <filename>os-release</filename> please refer to
the <ulink
url="http://0pointer.de/blog/projects/os-release">Announcement of <filename>/etc/os-release</filename></ulink>.</para>
</refsect1>
<title>Options</title>
<para>The following OS identifications parameters may be set using
- <filename>/etc/os-release</filename>:</para>
+ <filename>os-release</filename>:</para>
<variablelist>
~ianmdlvl / elogind.git / blobdiff