udev \- Linux configurable dynamic device naming support
.SH SYNOPSIS
.BI udev " hotplug-subsystem"
+.br
+.B udev
+.RI "[-q " sysfs_path "] [-rVh]"
.SH "DESCRIPTION"
.B udev
creates or removes device node files usually located in the /dev directory.
On device removal,
.B udev
queries the internal database for the name of the device file to be deleted.
+.SH "OPTIONS"
+.B udev
+normally is called by
+.B hotplug
+with the subsystem as argument and various environment variables set.
+.br
+It may also called with the following options:
+.TP
+.B -V
+Print the version information.
+.TP
+.B -r
+Print the the
+.B udev
+root directory.
+.TP
+.BI -q " sysfs_path"
+Query with the sysfs path as argument for the name of the created device node.
+.TP
+.B -h
+Print help text.
.SH "CONFIGURATION"
All
.B udev
# udev_permissions - The name and location of the udev permission file
udev_permissions="/etc/udev/udev.permissions"
-# default_mode - set the default mode for all nodes that have no
+# default_mode - set the default mode for all nodes that have no
# explicit match in the permissions file
default_mode="0666"
.fi
where valid methods with corresponding keys are:
.TP
.B CALLOUT
-calling external program, that returns a string to match
+calling external program, that returns a string to match. The
+.B BUS
+key is optional, but if specified, the sysfs device bus must be able to be
+determined by a "device" symlink.
.br
.RB "keys: " BUS ", " PROGRAM ", " ID
.TP
.B LABEL
device label or serial number, like USB serial number, SCSI UUID or
-file system label
+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. The
+.B BUS
+key is optional, but if specified, the sysfs device bus must be able to be
+detemined by a "device" symlink.
.br
.RB "keys: " BUS ", " SYSFS_
.TP
The "kernel number" of the device.
for example, 'sda3' has a "kernel number" of '3'
.TP
+.B %k
+The "kernel name" for the device.
+.TP
.B %M
The kernel major number for the device.
.TP
# USB printer to be called lp_color
LABEL, BUS="usb", SYSFS_serial="W09090207101241330", NAME="lp_color"
+# SCSI disk with a specific vendor and model number is to be called boot
+LABEL, BUS="scsi", SYSFS_vendor="IBM", SYSFS_model="ST336", NAME="boot%n"
+
# sound card with PCI bus id 00:0b.0 to be called dsp
NUMBER, BUS="pci", ID="00:0b.0", NAME="dsp"
REPLACE, KERNEL="ttyUSB1", NAME="pda", SYMLINK="palmtop handheld"
# multiple USB webcams with symlinks to be called webcam0, webcam1, ...
-LABEL, BUS="usb", model="WebCam V3", NAME="video%n", SYMLINK="webcam%n"
+LABEL, BUS="usb", SYSFS_model="XV3", NAME="video%n", SYMLINK="webcam%n"
.fi
.P
Permissions and ownership for the created device files may specified at