the custom rules directory <filename>/etc/udev/rules.d/</filename>
and the temporary rules directory <filename>/dev/.udev/rules.d/</filename>.
All rule files are sorted and processed in lexical order, regardless
- in which of these directories they live.</para>
+ in which of these directories they live. Files in
+ <filename>/etc/udev/rules.d/</filename> have precedence over files with
+ the same name in <filename>/lib/udev/rules.d/</filename>. This can be
+ used to ignore a default rules file if needed.</para>
- <para>Rule files are required to have a unique name, duplicate file names
- are ignored. Files in <filename>/etc/udev/rules.d/</filename> have precedence
- over files with the same name in <filename>/lib/udev/rules.d/</filename>. This
- can be used to ignore a default rules file if needed.</para>
+ <para>Rule files must end in <filename>.rules</filename>, other extensions
+ are ignored.</para>
<para>Every line in the rules file contains at least one key value pair.
There are two kind of keys, match and assignment keys.
by an earlier event.</para>
</listitem>
</varlistentry>
+ <varlistentry>
+ <term><option>cmdline</option></term>
+ <listitem>
+ <para>Import a single property from the kernel commandline. For simple flags
+ the value of the property will be set to '1'.</para>
+ </listitem>
+ </varlistentry>
<varlistentry>
<term><option>parent</option></term>
<listitem>
<term><option>WAIT_FOR</option></term>
<listitem>
<para>Wait for a file to become available or until a 10
- seconds timeout expires.</para>
+ seconds timeout expires. The path is relative to the sysfs device,
+ i. e. if no path is specified this waits for an attribute to appear.</para>
</listitem>
</varlistentry>
with this option.</para>
</listitem>
</varlistentry>
+ <varlistentry>
+ <term><option>static_node=</option></term>
+ <listitem>
+ <para>Apply the permissions specified in this rule to a static device node with
+ the specified name. Static device nodes might be provided by kernel modules,
+ or copied from <filename>/lib/udev/devices</filename>. These nodes might not have
+ a corresponding kernel device at the time udevd is started, and allow to trigger
+ automatic kernel module on-demand loading.</para>
+ </listitem>
+ </varlistentry>
<varlistentry>
<term><option>watch</option></term>
<listitem>
writing, a change uevent will be synthesised.</para>
</listitem>
</varlistentry>
+ <varlistentry>
+ <term><option>nowatch</option></term>
+ <listitem>
+ <para>Disable the watching of a device node with inotify.</para>
+ </listitem>
+ </varlistentry>
</variablelist>
</listitem>
</varlistentry>
<listitem>
<para>The value of a sysfs attribute found at the device, where
all keys of the rule have matched. If the matching device does not have
- such an attribute, follow the chain of parent devices and use the value
- of the first attribute that matches.
+ such an attribute, and a previous KERNELS, SUBSYSTEMS, DRIVERS, or
+ ATTRS test selected a parent device, use the attribute from that
+ parent device.
If the attribute is a symlink, the last element of the symlink target is
returned as the value.</para>
</listitem>