WinBioMonitorPresence function (winbio.h)
Turns on the face-recognition or iris-monitoring mechanism for the specified biometric unit. Starting with Windows 10, build 1607, this function is available to use with a mobile image.
Syntax
HRESULT WinBioMonitorPresence(
[in] WINBIO_SESSION_HANDLE SessionHandle,
[in] WINBIO_UNIT_ID UnitId
);
Parameters
[in] SessionHandle
An asynchronous handle for the biometric session that you obtained by calling the WinBioAsyncOpenSession function with the PoolType parameter set to WINBIO_POOL_SYSTEM.
[in] UnitId
The identifier of the biometric unit for which you want to turn on the face-recognition or iris-monitoring mechanism.
Return value
If the function parameters are acceptable, it returns S_OK. If the function parameters are not acceptable, it returns an HRESULT value that indicates the error.
Possible values include, but are not limited to, those in the following table. For a list of common error codes, see Common HRESULT Values.
| Return code | Description |
|---|---|
|
The session handle is not valid. |
|
The UnitId parameter cannot equal zero. |
|
The session handle does not correspond to an asynchronous biometric session. |
The actual success or failure of the operation itself is returned to the your notification function in a WINBIO_ASYNC_RESULT structure.
Remarks
A single biometric session can have only one active presence monitor at any point in time.
After you successfully call WinBioMonitorPresence, your notification function receives notifications in the form of a WINBIO_ASYNC_RESULT structure with an Operation member equal to WINBIO_OPERATION_MONITOR_PRESENCE. You should then examine the Parameters.MonitorPresence member of the WINBIO_ASYNC_RESULT structure for more information.
To stop receiving notifications, call either WinBioCancel or WinBioCloseSession with the original asynchronous handle value.
Requirements
| Requirement | Value |
|---|---|
| Minimum supported client | Windows 10 [desktop apps only] |
| Minimum supported server | Windows Server 2016 [desktop apps only] |
| Target Platform | Windows |
| Header | winbio.h |
| Library | Winbio.lib |
| DLL | Winbio.dll |