Was this page helpful?
Your feedback about this content is important. Let us know what you think.
Additional feedback?
1500 characters remaining
Export (0) Print
Expand All

SendAsyncProc callback function

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.

Syntax


VOID CALLBACK SendAsyncProc(
  _In_ HWND      hwnd,
  _In_ UINT      uMsg,
  _In_ ULONG_PTR dwData,
  _In_ LRESULT   lResult
);

Parameters

hwnd [in]

Type: HWND

A 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 [in]

Type: UINT

The message.

dwData [in]

Type: ULONG_PTR

An application-defined value sent from the SendMessageCallback function.

lResult [in]

Type: LRESULT

The result of the message processing. This value depends on the message.

Return value

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.

Requirements

Minimum supported client

Windows 2000 Professional [desktop apps only]

Minimum supported server

Windows 2000 Server [desktop apps only]

Header

Winuser.h (include Windows.h)

See also

Reference
GetMessage
PeekMessage
SendMessageCallback
WaitMessage
Conceptual
Messages and Message Queues

 

 

Community Additions

ADD
Show:
© 2015 Microsoft