.sp
.IR "key " ,[ "key " ,...]
.P
+Each key has the following format:
+.sp
+.IR "name op value"
+.P
+There are distinct key operation types, depending on the type of the key, it
+does a comparison or an assignment.
+.P
+Comparison operators are:
+.TP
+.B ==
+Compare for equality.
+.TP
+.B !=
+Compare for non-equality.
+.P
+Assignment operators are:
+.TP
+.B +=
+Add the value to a key that holds a list of entries.
+.TP
+.B :=
+Assign a value to a key finally; disallow any later changes, which
+is useful to prevent changes by any later rules.
+.TP
+.B =
+Asign a value to a key. Keys that represent a list, are reset and only this
+single value is assigned. While this operator still works inplicitely as
+comparison on keys that can't get a value assigned, its usage as an comparison
+operator is deprecated.
+.P
The following key names can be used to match against device properties:
.TP
.B BUS
.TP
.B NAME
The name of the node to be created, or the name, the network interface
-should be renamed to.
+should be renamed to. Only one rule can set the a name, all later rules
+with a NAME key will be ignored.
.TP
.B SYMLINK
The name of a symlink targeting the node. Every matching rule can add
.P
After device node creation, removal, or network device renaming,
.B udev
-executes the programs located in the directory tree under
-.IR /etc/dev.d/ .
-The name of a program must have the suffix
-.I .dev
-to be recognized.
+executes the programs specified by the
+.B RUN
+key.
.br
In addition to the kernel provided hotplug environment variables,
.B UDEV_LOG
Executed programs may want to follow that setting.
.B DEVNAME
is exported to make the name of the created node, or the name the network
-device is renamed to, available to the executed program. The programs in every
-directory are sorted in lexical order, while the directories are searched in
-the following order:
-.sp
-.nf
-/etc/dev.d/$(DEVNAME)/*.dev
-/etc/dev.d/$(SUBSYSTEM)/*.dev
-/etc/dev.d/default/*.dev
-.fi
+device is renamed to, available to the executed programs.
.SH "ENVIRONMENT"
.P
The following variables are read from the environment:
.TP
.B UDEV_RUN
If set to "0", it disables the execution of programs added by rules.
-.TP
-.B UDEV_NO_DEVD
-The default behavior of
-.B udev
-is to execute programs in the
-.I /etc/dev.d/
-directory after device handling. If set,
-.B udev
-will skip this step.
.SH "FILES"
.nf
/sbin/udev udev program
/etc/udev/* udev config files
-/etc/dev.d/* programs invoked by udev
.fi
.SH "SEE ALSO"
.BR udevinfo (8),