HwVidQueryNamedValueCallback

VP_STATUS HwVidQueryNamedValueCallback(

PVOID  HwDeviceExtension,
PVOID  Context,
PWSTR  ValueName,
PVOID  ValueData,
ULONG  ValueLength
);

HwVidQueryNamedValueCallback is an optional miniport driver function passed in a call to VideoPortGetRegistryParameters. VideoPortGetRegistryParameters calls HwVidQueryNamedValueCallback after collecting available configuration information about the given ValueName in the ..\CurrentControlSet\Services\DriverName\DeviceNumber key of the registry.

Parameters

HwDeviceExtension

Points to the miniport driver’s per-adapter storage area.

Context

Points to a driver-determined context to be passed to the callback routine. Usually, it points to a location on the stack at which the value data should be stored.

ValueName

Points to a zero-terminated Unicode string naming the entry.

ValueData

Points to the buffered data associated with ValueName, supplied by VideoPortGetRegistryParameters.

ValueLength

Specifies the size in bytes of the buffer at ValueData.

Return Value

HwVidQueryNamedValueCallback returns the status of the operation.

Comments

HwVidQueryNamedValueCallback processes the ValueData retrieved from the registry.

The returned ValueData is on the stack, so it can be referenced locally. HwVidQueryNamedValueCallback can store some or all of the returned information for use by other miniport functions in the input HwDeviceExtension or use the input Context as a pointer to a location where the data can be stored.

See Also

HwVidFindAdapter, VideoPortGetRegistryParameters, VideoPortSetRegistryParameters