USB event environment

argv[0] = hotplug_path
argv[1] = usb
argv[2] = 0

HOME = /
PATH = /sbin:/bin:/usr/sbin:/usr/bin
PRODUCT = idVendor/idProduct/bcdDevice
TYPE = device_class/device_subclass/device_protocol
ACTION = action

if device_class == 0 then
INTERFACE = class/subclass/protocol


action=(add|remove)

red is actual values
green is replaced with runtime information