mirror of
https://github.com/systemd/systemd-stable.git
synced 2024-12-23 17:34:00 +03:00
86 lines
3.7 KiB
XML
86 lines
3.7 KiB
XML
<?xml version='1.0'?> <!--*- Mode: nxml; nxml-child-indent: 2; indent-tabs-mode: nil -*-->
|
|
<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
|
|
"http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
|
|
|
|
<refentry id="hwdb" conditional="ENABLE_HWDB">
|
|
<refentryinfo>
|
|
<title>hwdb</title>
|
|
<productname>systemd</productname>
|
|
<authorgroup>
|
|
<author>
|
|
<contrib>Developer</contrib>
|
|
<firstname>Kay</firstname>
|
|
<surname>Sievers</surname>
|
|
<email>kay@vrfy.org</email>
|
|
</author>
|
|
<author>
|
|
<contrib>Developer</contrib>
|
|
<firstname>Tom</firstname>
|
|
<surname>Gundersen</surname>
|
|
<email>teg@jklm.no</email>
|
|
</author>
|
|
</authorgroup>
|
|
</refentryinfo>
|
|
|
|
<refmeta>
|
|
<refentrytitle>hwdb</refentrytitle>
|
|
<manvolnum>7</manvolnum>
|
|
</refmeta>
|
|
|
|
<refnamediv>
|
|
<refname>hwdb</refname>
|
|
<refpurpose>Hardware Database</refpurpose>
|
|
</refnamediv>
|
|
|
|
<refsect1><title>Description</title>
|
|
<para>The hardware database is a key-value store for associating modalias-like keys to
|
|
udev-property-like values. It is used primarily by udev to add the relevant properties
|
|
to matching devices, but it can also be queried directly.</para>
|
|
</refsect1>
|
|
|
|
<refsect1><title>Hardware Database Files</title>
|
|
<para>The hwdb files are read from the files located in the
|
|
system hwdb directory <filename>/usr/lib/udev/hwdb.d</filename> and
|
|
the local administration directory <filename>/etc/udev/hwdb.d</filename>.
|
|
All hwdb files are collectively sorted and processed in lexical order,
|
|
regardless of the directories in which they live. However, files with
|
|
identical filenames replace each other. Files in <filename>/etc</filename>
|
|
have the highest priority and take precedence over files with the same
|
|
name in <filename>/usr/lib</filename>. This can be used to override a
|
|
system-supplied hwdb file with a local file if needed;
|
|
a symlink in <filename>/etc</filename> with the same name as a hwdb file in
|
|
<filename>/usr/lib</filename>, pointing to <filename>/dev/null</filename>,
|
|
disables the hwdb file entirely. hwdb files must have the extension
|
|
<filename>.hwdb</filename>; other extensions are ignored.</para>
|
|
|
|
<para>The hwdb file contains data records consisting of matches and
|
|
associated key-value pairs. Every record in the hwdb starts with one or
|
|
more match strings, specifying a shell glob to compare the database
|
|
lookup string against. Multiple match lines are specified in additional
|
|
consecutive lines. Every match line is compared individually, and they are
|
|
combined by OR. Every match line must start at the first character of
|
|
the line.</para>
|
|
|
|
<para>The match lines are followed by one or more key-value pair lines, which
|
|
are recognized by a leading space character. The key name and value are separated
|
|
by <literal>=</literal>. An empty line signifies the end
|
|
of a record. Lines beginning with <literal>#</literal> are ignored.</para>
|
|
|
|
<para>The content of all hwdb files is read by
|
|
<citerefentry><refentrytitle>systemd-hwdb</refentrytitle><manvolnum>8</manvolnum></citerefentry>
|
|
and compiled to a binary database located at <filename>/etc/udev/hwdb.bin</filename>,
|
|
or alternatively <filename>/usr/lib/udev/hwdb.bin</filename> if you want ship the compiled
|
|
database in an immutable image.
|
|
During runtime, only the binary database is used.</para>
|
|
</refsect1>
|
|
|
|
<refsect1>
|
|
<title>See Also</title>
|
|
<para>
|
|
<citerefentry>
|
|
<refentrytitle>systemd-hwdb</refentrytitle><manvolnum>8</manvolnum>
|
|
</citerefentry>
|
|
</para>
|
|
</refsect1>
|
|
</refentry>
|