NCH Obble Smith wrote: > I believe I am catching out the way out. Do I have to > MmProbeAndLockPages the Irp->UserBuffer??? You shouldn't have to; all of this should take place in the calling process context. This is just a data structure request. No I/O is required. You should see a KSMULTIPLE_ITEM as the first thing in UserBuffer, followed by a number of data ranges, as given by the KSMULTIPLE_ITEM. Is there an error code in the IRP? The caller might have to issue this once with a short buffer, to find out how much data there will be, then issue it again with the real buffer. -- Tim Roberts, timr@xxxxxxxxx Providenza & Boekelheide, Inc. ****************** WDMAUDIODEV addresses: Post message: mailto:wdmaudiodev@xxxxxxxxxxxxx Subscribe: mailto:wdmaudiodev-request@xxxxxxxxxxxxx?subject=subscribe Unsubscribe: mailto:wdmaudiodev-request@xxxxxxxxxxxxx?subject=unsubscribe Moderator: mailto:wdmaudiodev-moderators@xxxxxxxxxxxxx URL to WDMAUDIODEV page: http://www.wdmaudiodev.com/