The SendMessageCallback function sends the specified message to a window or windows. The function calls the window procedure for the specified window and returns immediately. After the window procedure processes the message, the system calls the specified callback function, passing the result of the message processing and an application-defined value to the callback function.
BOOL SendMessageCallback(
HWND hWnd, |
// handle of destination window |
UINT Msg, |
// message to send |
WPARAM wParam, |
// first message parameter |
LPARAM lParam, |
// second message parameter |
SENDASYNCPROC lpResultCallBack, |
// function to receive message value |
DWORD dwData |
// value to pass to callback function |
); |
If hWnd is HWND_BROADCAST, the operating system calls the SendAsyncProc
callback function once for each top-level window.
If the function succeeds, the return value is nonzero.
If the function fails, the return value is zero. To get extended error information, call GetLastError.
If you send a message in the range below WM_USER to the asynchronous message functions (PostMessage, SendNotifyMessage, and SendMessageCallback), make sure that the message parameters do not include pointers. Otherwise, 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.
Applications that need to communicate using HWND_BROADCAST should use the RegisterWindowMessage function to obtain a unique message for inter-application communication.
The callback function is called only when the thread that called SendMessageCallback also calls GetMessage, PeekMessage, or WaitMessage.
PostMessage, RegisterWindowMessage, SendAsyncProc, SendMessageCallback, SendNotifyMessage
file: /Techref/os/win/api/win32/func/src/f75_16.htm, 5KB, , updated: 2000/4/7 12:19, local time: 2024/8/23 13:50,
18.116.14.94:LOG IN
|
©2024 These pages are served without commercial sponsorship. (No popup ads, etc...).Bandwidth abuse increases hosting cost forcing sponsorship or shutdown. This server aggressively defends against automated copying for any reason including offline viewing, duplication, etc... Please respect this requirement and DO NOT RIP THIS SITE. Questions? <A HREF="http://massmind.org/Techref/os/win/api/win32/func/src/f75_16.htm"> SendMessageCallback</A> |
Did you find what you needed? |
Welcome to massmind.org! |
Ashley Roll has put together a really nice little unit here. Leave off the MAX232 and keep these handy for the few times you need true RS232! |
.