.SH SYNOPSIS
.BI udev " hotplug-subsystem"
.P
-The environment must provide the following variables:
+The following variables are read from the environment:
.TP
.B ACTION
.IR add " or " remove
-signifies the connection or disconnection of a device.
-.TP
+signifies the addition or the removal of a device.
+.P
.B DEVPATH
The sysfs devpath of the device without the mountpoint but a leading slash.
.P
-Additional optional environment variables:
-.TP
+.B SUBSYSTEM
+The subsystem the device belongs to. Alternatively the subsystem may
+be passed as the first argument.
+.P
.B UDEV_CONFIG_FILE
Overrides the default location of the
.B udev
config file.
-.TP
+.P
.B UDEV_NO_DEVD
The default behavior of
.B udev
present devices. It creates or removes device node files usually located in
the /dev directory, or it renames network interfaces.
.br
-
.P
As part of the
.B hotplug
.BR NAME{ all_partitions }
it will create all 15 partitions of a blockdevice.
This may be useful for removable media devices.
+.br
+If given with the attribute
+.BR NAME{ ignore_remove }
+it will will ignore any later remove event for this device.
+This may be useful as a workaround for broken device drivers.
+.sp
+Multiple attributes may be separated by comma.
.TP
.B SYMLINK
The name of a symlink targeting the node. Multiple symlinks may be
suffix, to be recognized.
.br
In addition to the hotplug environment variables,
+.B UDEV_LOG
+is set if udev is configured to use the syslog facility. 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
+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