From: 江民 on
Hi Maxim:
Thanks for you advice!

My driver is XDDM type, and all the interface functions
exported by videoport use hardware extension structure, the "device
object" which is used by IoOpenDeviceRegistryKey can't be got.

Also before i can use the ioctl, i will need to know
which display driver should be used, So the IOCTl also can't be used.