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QUERY_INTERFACE structure (video.h)

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The QUERY_INTERFACE structure describes the interface being requested.

Syntax

typedef struct _QUERY_INTERFACE {
  const GUID *InterfaceType;
  USHORT     Size;
  USHORT     Version;
  PINTERFACE Interface;
  PVOID      InterfaceSpecificData;
  ULONG      DeviceUid;
} QUERY_INTERFACE, *PQUERY_INTERFACE;

Members

InterfaceType

Pointer to a GUID that identifies the interface being requested. If the kernel-mode display miniport driver (KMD) (or legacy video miniport driver) doesn't support the specified InterfaceType, it should fail the call and return immediately.

The parent generates this GUID with uuidgen.exe. See Defining and Exporting New GUIDs for details.

Size

Specifies the size in bytes of the INTERFACE structure to which Interface points. The driver must not return an INTERFACE structure larger than Size bytes.

Version

Specifies the version of the interface being requested.

If a parent supports more than one version of an interface, its driver should return the specified version or, if possible, the closest supported version without exceeding the requested version. The caller is responsible for examining the returned Version and determine what to do based on that value.

Interface

Pointer to an INTERFACE structure in which the driver returns the requested interface information. The caller is responsible for allocating this structure before calling DxgkddiQueryInterface (or HwVidQueryInterface).

InterfaceSpecificData

Specifies additional information about the interface being requested. Typically, this member is NULL, and the InterfaceType and Version members are sufficient for the parent to identify the interface being requested.

DeviceUid

A positive integer that identifies the device for which the interface is being queried. If DeviceUid is equal to DISPLAY_ADAPTER_HW_ID (defined in Video.h), the device is the display adapter itself. Otherwise, DeviceUid is the identifier of a child device of the display adapter. Child device identifiers were previously assigned by the DxgkDdiQueryChildRelations function. Available starting with Windows 8.1 (WDDM 1.3).

Remarks

The QueryInterface parameter of the KMD's DxgkddiQueryInterface callback (or legacy video miniport driver's HwVidQueryInterface function) is a pointer to a QUERY_INTERFACE structure.

Requirements

Requirement Value
Header video.h (include Video.h)

See also

DxgkddiQueryInterface

HwVidQueryInterface