Description:
PMIREQUEST_LOCKREGISTERS locks extended registers.
#include <svgadefs.h>
PVIDEO_ADAPTER pAdapter; /* Pointer to a VIDEO_ADAPTER data structure. */
ULONG ulFunction; /* Set equal to PMIREQUEST_LOCKREGISTERS. */
PVOID pIn; /* NULL. */
PVOID pOut; /* NULL. */
APIRET rc; /* Return codes. */
rc = VIDEOPMI32Request(pAdapter, ulFunction,
pIn, pOut);