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PWINBIO_LOCATE_SENSOR_CALLBACK callback function (winbio.h)

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Called by the Windows Biometric Framework to return results from the asynchronous WinBioLocateSensorWithCallback function. The client application must implement this function.

Important  We recommend that, beginning with Windows 8, you no longer use the PWINBIO_LOCATE_SENSOR_CALLBACK/WinBioLocateSensorWithCallback combination. Instead, do the following:
  • Implement a PWINBIO_ASYNC_COMPLETION_CALLBACK function to receive notice when the operation completes.
  • Call the WinBioAsyncOpenSession function. Pass the address of your callback in the CallbackRoutine parameter. Pass WINBIO_ASYNC_NOTIFY_CALLBACK in the NotificationMethod parameter. Retrieve an asynchronous session handle.
  • Use the asynchronous session handle to call WinBioLocateSensor. When the operation finishes, the Windows Biometric Framework will allocate and initialize a WINBIO_ASYNC_RESULT structure with the results and invoke your callback with a pointer to the results structure.
  • Call WinBioFree from your callback implementation to release the WINBIO_ASYNC_RESULT structure after you have finished using it.
 

Syntax

PWINBIO_LOCATE_SENSOR_CALLBACK PwinbioLocateSensorCallback;

void PwinbioLocateSensorCallback(
  [in, optional] PVOID LocateCallbackContext,
  [in]           HRESULT OperationStatus,
                 WINBIO_UNIT_ID UnitId
)
{...}

Parameters

[in, optional] LocateCallbackContext

Pointer to a buffer defined by the application and passed to the LocateCallbackContext parameter of the WinBioLocateSensorWithCallback function. The buffer is not modified by the framework or the biometric unit. Your application can use the data to help it determine what actions to perform or to maintain additional information about the biometric capture.

[in] OperationStatus

Error code returned by the capture operation.

UnitId

Biometric unit ID number.

Return value

None

Requirements

Requirement Value
Minimum supported client Windows 7 [desktop apps only]
Minimum supported server Windows Server 2008 R2 [desktop apps only]
Target Platform Windows
Header winbio.h