WinBioCloseSession function

Closes a biometric session and releases associated resources.

Syntax


HRESULT WINAPI WinBioCloseSession(
  _In_  WINBIO_SESSION_HANDLE SessionHandle
);

Parameters

SessionHandle [in]

A WINBIO_SESSION_HANDLE value that identifies an open biometric session. Open a synchronous session handle by calling WinBioOpenSession. Open an asynchronous session handle by calling WinBioAsyncOpenSession.

Return value

If the function succeeds, it returns S_OK. If the function fails, 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 codeDescription
E_HANDLE

The session handle is not valid.

 

Remarks

To use WinBioCloseSession synchronously, call the function with a session handle created by calling WinBioOpenSession. The function blocks until the operation completes or an error is encountered.

To use WinBioCloseSession asynchronously, call the function with a session handle created by calling WinBioAsyncOpenSession. The framework allocates a WINBIO_ASYNC_RESULT structure and uses it to return information about operation success or failure. The WINBIO_ASYNC_RESULT structure is returned to the application callback or to the application message queue, depending on the value you set in the NotificationMethod parameter of the WinBioAsyncOpenSession function.

  • If you choose to receive completion notices by using a callback, you must implement a PWINBIO_ASYNC_COMPLETION_CALLBACK function and set the NotificationMethod parameter to WINBIO_ASYNC_NOTIFY_CALLBACK.
  • If you choose to receive completion notices by using the application message queue, you must set the NotificationMethod parameter to WINBIO_ASYNC_NOTIFY_MESSAGE. The framework returns a WINBIO_ASYNC_RESULT pointer to the LPARAM field of the window message.

To prevent memory leaks, you must call WinBioFree from your callback implementation to release the WINBIO_ASYNC_RESULT structure after you have finished using it.

Examples

The following function shows how to enumerate the biometric sub-factors enrolled for a template. The sample creates a connection to the system pool and keeps the connection open until calling WinBioCloseSession during cleanup. Link to the Winbio.lib static library and include the following header files:

  • Windows.h
  • Stdio.h
  • Conio.h
  • Winbio.h

HRESULT EnumEnrollments( )
{
    // Declare variables.
    HRESULT hr = S_OK;
    WINBIO_IDENTITY identity = {0};
    WINBIO_SESSION_HANDLE sessionHandle = NULL;
    WINBIO_UNIT_ID unitId = 0;
    PWINBIO_BIOMETRIC_SUBTYPE subFactorArray = NULL;
    WINBIO_BIOMETRIC_SUBTYPE SubFactor = 0;
    SIZE_T subFactorCount = 0;
    WINBIO_REJECT_DETAIL rejectDetail = 0;
    WINBIO_BIOMETRIC_SUBTYPE subFactor = WINBIO_SUBTYPE_NO_INFORMATION;

    // Connect to the system pool. 
    hr = WinBioOpenSession( 
            WINBIO_TYPE_FINGERPRINT,    // Service provider
            WINBIO_POOL_SYSTEM,         // Pool type
            WINBIO_FLAG_DEFAULT,        // Configuration and access
            NULL,                       // Array of biometric unit IDs
            0,                          // Count of biometric unit IDs
            NULL,                       // Database ID
            &sessionHandle              // [out] Session handle
            );
    if (FAILED(hr))
    {
        wprintf_s(L"\n WinBioOpenSession failed. hr = 0x%x\n", hr);
        goto e_Exit;
    }

    // Locate the biometric sensor and retrieve a WINBIO_IDENTITY object.
    wprintf_s(L"\n Calling WinBioIdentify - Swipe finger on sensor...\n");
    hr = WinBioIdentify( 
            sessionHandle,              // Session handle
            &unitId,                    // Biometric unit ID
            &identity,                  // User SID
            &subFactor,                 // Finger sub factor
            &rejectDetail               // Rejection information
            );
    wprintf_s(L"\n Swipe processed - Unit ID: %d\n", unitId);
    if (FAILED(hr))
    {
        if (hr == WINBIO_E_UNKNOWN_ID)
        {
            wprintf_s(L"\n Unknown identity.\n");
        }
        else if (hr == WINBIO_E_BAD_CAPTURE)
        {
            wprintf_s(L"\n Bad capture; reason: %d\n", rejectDetail);
        }
        else
        {
            wprintf_s(L"\n WinBioEnumBiometricUnits failed. hr = 0x%x\n", hr);
        }
        goto e_Exit;
    }

    // Retrieve the biometric sub-factors for the template.
    hr = WinBioEnumEnrollments( 
            sessionHandle,              // Session handle
            unitId,                     // Biometric unit ID
            &identity,                  // Template ID
            &subFactorArray,            // Subfactors
            &subFactorCount             // Count of subfactors
            );
    if (FAILED(hr))
    {
        wprintf_s(L"\n WinBioEnumEnrollments failed. hr = 0x%x\n", hr);
        goto e_Exit;
    }

    // Print the sub-factor(s) to the console.
    wprintf_s(L"\n Enrollments for this user on Unit ID %d:", unitId);
    for (SIZE_T index = 0; index < subFactorCount; ++index)
    {
        SubFactor = subFactorArray[index];
        switch (SubFactor)
        {
            case WINBIO_ANSI_381_POS_RH_THUMB:
                wprintf_s(L"\n   RH thumb\n");
                break;
            case WINBIO_ANSI_381_POS_RH_INDEX_FINGER:
                wprintf_s(L"\n   RH index finger\n");
                break;
            case WINBIO_ANSI_381_POS_RH_MIDDLE_FINGER:
                wprintf_s(L"\n   RH middle finger\n");
                break;
            case WINBIO_ANSI_381_POS_RH_RING_FINGER:
                wprintf_s(L"\n   RH ring finger\n");
                break;
            case WINBIO_ANSI_381_POS_RH_LITTLE_FINGER:
                wprintf_s(L"\n   RH little finger\n");
                break;
            case WINBIO_ANSI_381_POS_LH_THUMB:
                wprintf_s(L"\n   LH thumb\n");
                break;
            case WINBIO_ANSI_381_POS_LH_INDEX_FINGER:
                wprintf_s(L"\n   LH index finger\n");
                break;
            case WINBIO_ANSI_381_POS_LH_MIDDLE_FINGER:
                wprintf_s(L"\n   LH middle finger\n");
                break;
            case WINBIO_ANSI_381_POS_LH_RING_FINGER:
                wprintf_s(L"\n   LH ring finger\n");
                break;
            case WINBIO_ANSI_381_POS_LH_LITTLE_FINGER:
                wprintf_s(L"\n   LH little finger\n");
                break;
            default:
                wprintf_s(L"\n   The sub-factor is not correct\n");
                break;
        }
 
    }

e_Exit:
    if (subFactorArray!= NULL)
    {
        WinBioFree(subFactorArray);
        subFactorArray = NULL;
    }

    if (sessionHandle != NULL)
    {
        WinBioCloseSession(sessionHandle);
        sessionHandle = NULL;
    }

    wprintf_s(L"\n Press any key to exit...");
    _getch();

    return hr;
}



Requirements

Minimum supported client

Windows 7 [desktop apps only]

Minimum supported server

Windows Server 2008 R2 [desktop apps only]

Header

Winbio.h (include Winbio.h)

Library

Winbio.lib

DLL

Winbio.dll

See also

WinBioOpenSession

 

 

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