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VideoPortGetDmaContext function (video.h)

The VideoPortGetDmaContext function is obsolete in Windows 2000 and later.

VideoPortGetDmaContext gets the context previously associated with the specified DMA handle.

Syntax

VIDEOPORT_DEPRECATED VIDEOPORT_API PVOID VideoPortGetDmaContext(
  [in] IN PVOID HwDeviceExtension,
  [in] IN PDMA  pDma
);

Parameters

[in] HwDeviceExtension

Pointer to the miniport driver's device extension.

[in] pDma

Pointer to a DMA handle. To obtain the appropriate DMA handle, use the value in the OutputBuffer member of the pVrp parameter after VideoPortLockPages returns.

Return value

VideoPortGetDmaContext always returns NULL.

Remarks

See Bus-Master DMA in Video Miniport Drivers for information about packet-based and common-buffer DMA transfers.

Requirements

Requirement Value
Minimum supported client Available in Windows 2000 and later versions of the Windows operating systems.
Target Platform Desktop
Header video.h (include Video.h)
Library Videoprt.lib
DLL Videoprt.sys