UI_METHOD functions not being invoked for smart card

[George <whippet0@xxxxxxxxx>]

    Hi,
    
        I'm trying to get OpenSSL 1.0.2u with the FIPS Object Module
    2.0.16  in Windows 10 to prompt the user for a smart card's PIN
    number every time the application is launched. However, I cannot
    seem to get it to work. My UI_METHOD callback functions are not
    being invoked.
    
    I'm using the following code as a reference:
    https://github.com/jjkeijser/ppp/blob/eap-tls/pppd/eap-tls.c
    
    I tried the following:
    
> UI_METHOD* transfer_pin =
>         UI_create_method("transfer_pin");
>         
>         int writer (UI *ui, UI_STRING *uis)
>         {
>             PW_CB_DATA* cb_data = (PW_CB_DATA*)UI_get0_user_data(ui);
>             UI_set_result(ui, uis, cb_data->password);
>             return 1;
>         };
>         int stub (UI* ui) {return 1;};
>         int stub_reader (UI *ui, UI_STRING *uis) {return 1;};
>         
>         UI_method_set_writer(transfer_pin,  writer);
>         UI_method_set_opener(transfer_pin,  stub);
>         UI_method_set_closer(transfer_pin,  stub);
>         UI_method_set_flusher(transfer_pin, stub);
>         UI_method_set_reader(transfer_pin,  stub_reader);
>         
>         pkey = ENGINE_load_private_key(pkey_engine, pkey_identifier,
>         transfer_pin, &cb_data);
>       
    
    
    However, none of the callback functions "writer", "stub", or
    "stub_reader" actually get called. Do I need to do anything else to
    enable this functionality?  I would like to force the user to enter
    PIN number every time.
    
    
    
    Thanks,
    George