-.B REPLACE
-string replacement of the kernel device name
-.br
-.RB "key: " KERNEL
-.P
-The methods are applied in the following order:
-.BR CALLOUT ", " LABEL ", " NUMBER ", " TOPOLOGY ", " REPLACE "."
+.BI SYSFS_ filename
+Match sysfs device attribute like label, vendor, USB serial number, SCSI UUID
+or file system label. Up to 5 different sysfs files can be checked, with
+all of the values being required in order to match the rule.
+.TP
+.B PROGRAM
+Call external program. This key is valid if the program returns successful.
+The string returned by the program may additionally matched with the
+.B RESULT
+key.
+.TP
+.B RESULT
+Match the returned string of the last
+.B PROGRAM
+call. This key may used in any following rule after a
+.B PROGRAM
+call.