-<?xml version='1.0'?>
+<?xml version='1.0'?> <!--*- Mode: nxml; nxml-child-indent: 2; indent-tabs-mode: nil -*-->
<?xml-stylesheet type="text/xsl" href="http://docbook.sourceforge.net/release/xsl/current/xhtml/docbook.xsl"?>
<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
"http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
</listitem>
</varlistentry>
+ <varlistentry>
+ <term><literal>-=</literal></term>
+ <listitem>
+ <para>Remove the value from a key that holds a list of entries.</para>
+ </listitem>
+ </varlistentry>
+
<varlistentry>
<term><literal>:=</literal></term>
<listitem>
<para>Execute a program to determine whether there
is a match; the key is true if the program returns
successfully. The device properties are made available to the
- executed program in the environment. The program's standard ouput
+ executed program in the environment. The program's standard output
is available in the <varname>RESULT</varname> key.</para>
<para>This can only be used for very short-running foreground tasks. For details,
see <varname>RUN</varname>.</para>
</varlistentry>
</variablelist>
- <para>Most of the fields support shell glob pattern matching. The following
- pattern characters are supported:</para>
+ <para>Most of the fields support shell glob pattern matching and
+ alternate patterns. The following special characters are supported:</para>
<variablelist>
<varlistentry>
<term><literal>*</literal></term>
any characters not enclosed are matched.</para>
</listitem>
</varlistentry>
+ <varlistentry>
+ <term><literal>|</literal></term>
+ <listitem>
+ <para>Separates alternative patterns. For example, the pattern string
+ <literal>abc|x*</literal> would match either <literal>abc</literal>
+ or <literal>x*</literal>.</para>
+ </listitem>
+ </varlistentry>
</variablelist>
<para>The following keys can get values assigned:</para>
priorities overwrite existing symlinks of other devices. The default is 0.</para>
</listitem>
</varlistentry>
- <varlistentry>
- <term><option>event_timeout=</option></term>
- <listitem>
- <para>Number of seconds an event waits for operations to finish before
- giving up and terminating itself.</para>
- </listitem>
- </varlistentry>
<varlistentry>
<term><option>string_escape=<replaceable>none|replace</replaceable></option></term>
<listitem>
</variablelist>
</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>,
- the volatile runtime directory <filename>/run/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, files in <filename>/run</filename> 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 string, 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 indivdually, 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>udevadm</refentrytitle><manvolnum>8</manvolnum></citerefentry>
- and compiled to a binary database located at <filename>/etc/udev/hwdb.bin</filename>.
- During runtime only the binary database is used.</para>
- </refsect1>
-
<refsect1>
<title>See Also</title>
<para>
</citerefentry>,
<citerefentry>
<refentrytitle>udevadm</refentrytitle><manvolnum>8</manvolnum>
- </citerefentry>
+ </citerefentry>,
<citerefentry>
<refentrytitle>systemd.link</refentrytitle><manvolnum>5</manvolnum>
</citerefentry>