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Please see Azure Cognitive Services for Speech documentation for the latest supported speech solutions.

Microsoft Speech Platform

ISpNotifySource::SetNotifyCallbackFunction

ISpNotifySource::SetNotifyCallbackFunction sets up this instance to send notifications using a standard C-style callback function.

<pre IsFakePre="true" xmlns="http://www.w3.org/1999/xhtml"> <strong>HRESULT SetNotifyCallbackFunction(</strong> <strong>SPNOTIFYCALLBACK</strong> <em>*pfnCallback</em>, <strong>WPARAM</strong> <em>wParam</em>, <strong>LPARAM</strong> <em>lParam</em> <strong>);</strong> </pre>

Parameters

  • pfnCallback
    [in] The notification callback function to be used.
  • wParam
    [in] Constant WPARAM value that will be passed to the pfnCallback function when it is called.
  • lParam
    [in] Constant LPARAM value that will be passed to the pfnCallback function when it is called.

Return Values

Value Description
S_OK Function completed successfully.
E_INVALIDARG Callback function is invalid.
FAILED (hr) Appropriate error message.

Remarks

It is the responsibility of the client code to control the lifetime of a notification. To remove an installed notify callback, call ISpEventSource::SetNotifySink (NULL). The final release of an object that supports ISpEventSource will automatically remove an installed notify callback.

The Speech Platform implementation uses a hidden window to call back the client on the same thread that was used to initialize the event source. Notification callbacks are the result of processing a window message. When this notification mechanism is used:

  1. The SPNOTIFYCALLBACK method will always be called on the thread that initialized the event source or notify translator object.
  2. The thread must have a window message pump.

The SPNOTIFYCALLBACK function is declared as follows:

    typedef void __stdcall SPNOTIFYCALLBACK(WPARAM wParam, LPARAM lParam);