SendNotifyMessage

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Windows Embedded CE 6.0 R3

4/8/2010

This function sends the specified message to the given window. If the window is created by the calling thread, SendNotifyMessage calls the window procedure for the window and does not return until the window procedure has processed the message. If the window was created by a different thread, SendNotifyMessage passes the message to the window procedure and returns immediately; it does not wait for the window procedure to finish processing the message.

Syntax

BOOL SendNotifyMessage(
  HWND hWnd, 
  UINT Msg, 
  WPARAM wParam, 
  LPARAM lParam 
);

Parameters

• hWnd
  [in] Handle to the window whose window procedure will receive the message. If this parameter is HWND_BROADCAST, the message is sent to all top-level windows in the system, including disabled or invisible unowned windows, overlapped windows, and pop-up windows; but the message is not sent to child windows.

• Msg
  [in] Specifies the message to be sent.

• wParam
  [in] Specifies additional message-specific information.

• lParam
  [in] Specifies additional message-specific information.

Return Value

Nonzero indicates success. Zero indicates failure. To get extended error information, call GetLastError.

Remarks

Applications that need to communicate using HWND_BROADCAST should use the RegisterWindowMessage function to obtain a unique message for inter-application communication.

If you send a message in the range below WM_USER to the asynchronous message functions (PostMessage and SendNotifyMessage), its message parameters cannot include pointers. Otherwise, the operation will fail. The functions will return before the receiving thread has had a chance to process the message and the sender will free the memory before it is used.

Windows Embedded CE does not support all the messages the Windows-based desktop platforms support.

Requirements

See Also

Reference

Message Queue Functions
PostMessage
PostThreadMessage
RegisterWindowMessage
SendMessage
WM_USER