Define your IOCTL's just follow the rules of the DDK page "Defining I/O
Control Codes" in particular the following from that page:

Designers of drivers for a new FILE_DEVICE_XXX type of device must set the
Common flag at bit 31 in the private I/O control codes they define. Those
who define a private set of I/O control codes for IRP_MJ_DEVICE_CONTROL or
IRP_MJ_INTERNAL_DEVICE_CONTROL requests also must set the Custom flag at bit
13 in the I/O control codes they define.
All system-defined I/O control codes have both these C flags cleared.

You will never reciver a IRP_MJ_INTERNAL_DEVICE_CONTROL on a call from a
user space program. Go study the IOCTL sample under general in the current
DDK.


Don Burn (MVP, Windows DDK)
Windows 2k/XP/2k3 Filesystem and Driver Consulting


"Kobus Engelbrecht" <kobus.engelbrecht@kentron.co.za> wrote in message
news:06ff01c34de3$17611860$a301280a@phx.gbl...