SendAsyncProc

The SendAsyncProc function is an application-defined callback function used with the SendMessageCallback function. The system passes the message to the callback function after passing the message to the destination window procedure. The SENDASYNCPROC type defines a pointer to this callback function. SendAsyncProc is a placeholder for the application-defined function name.

VOID CALLBACK SendAsyncProc(
  HWND hwnd,        // handle of destination window
  UINT uMsg,        // message
  DWORD dwData,     // application-defined value
  LRESULT lResult   // result of message processing
);
 

Parameters

hwnd

Handle to the window whose window procedure received the message.

If the SendMessageCallback function was called with its hwnd parameter set to HWND_BROADCAST, the system calls the SendAsyncProc function once for each top-level window.

uMsg

Specifies the message.

dwData

Specifies an application-defined value sent from the SendMessageCallback function.

lResult

Specifies the result of the message processing and depends on the message.

Return Values

This callback function does not return a value.

Remarks

You install a SendAsyncProc application-defined callback function by passing a SENDASYNCPROC pointer to the SendMessageCallback function.

The callback function is only called when the thread that called SendMessageCallback calls GetMessage, PeekMessage, or WaitMessage.

QuickInfo

  Windows NT: Requires version 3.1 or later.
  Windows: Requires Windows 95 or later.
  Windows CE: Unsupported.
  Header: Declared in winuser.h.
  Import Library: User-defined.

See Also

Messages and Message Queues Overview, Message and Message Queue Functions, GetMessage, PeekMessage, SendMessageCallback, WaitMessage