>the value returned from SetupDiGetClassDevs is a HANDLE, just like a HWND (window handle).
>It's not an array, its just a single 32bit value you pass on plain to other functions.

Well, Tracy did that, just passed the handle on.

The MSDN help isn't exact about the HDEVINFO, although the H suggests it's a Handle, true.

Help on SetupDiGetClassDevs says it returns a handle to a device information set. Help on SetupDiEnumDeviceInterfaces says, the DeviceInfoSet parameter is a pointer to a device information set that contains the device interfaces for which to return information. And right after talking about a pointer it says: "This handle is typically returned by SetupDiGetClassDevs".

So the real problem was not setting up the lcInterfaceData Buffer, not that pointer/handle thing, if I got you right.

I know for foxpro numeric variables are all the same, but vfp help on Declare-DLL also makes this slight difference between LONG and INTEGER...

Bye, Olaf.