- default rules directory <filename>/lib/udev/rules.d/</filename>,
- 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>
-
- <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>Every line in the rules file contains at least one key value pair.
- There are two kind of keys, match and assignment keys.
+ system rules directory <filename>/lib/udev/rules.d/</filename>,
+ the local administration directory <filename>/etc/udev/rules.d/</filename>
+ and the volatile runtime directory <filename>/run/udev/rules.d/</filename>.
+ All rules files are collectively sorted and processed in lexical order,
+ regardless of the directories in which they live. However, files with
+ identical file names replace each other. Files in <filename>/run</filename>
+ have the highest priority, files in <filename>/etc</filename> take precedence
+ over files with the same name in <filename>/lib</filename>. This can be
+ used to overwrite a system rules file if needed; a symlink in
+ <filename>/etc</filename> with the same name as a rules file in
+ <filename>/lib</filename>, pointing to <filename>/dev/null</filename>,
+ disables the rules file entirely.</para>
+
+ <para>Rule files must have the extension <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.