NAME¶

CallWindowProcA (USER32.@)

SYNOPSIS¶

LRESULT CallWindowProcA
(
WNDPROC func,
HWND hwnd,
UINT msg,
WPARAM wParam,
LPARAM lParam
)

PARAMS¶

func [In] window procedure. hwnd [In] target window. msg [In] message. wParam [In] message dependent parameter. [In] message dependent parameter.

DESCRIPTION¶

The CallWindowProc(3w) function invokes the Windows(tm) procedure _func_, with _hwnd_ as the target window, the message specified by _msg_, and the message parameters _wParam_ and _lParam_. Some kinds of argument conversion may be done, I'm not sure what. CallWindowProc() may be used for Windows(tm) subclassing. Use SetWindowLong() to set a new Windows(tm) procedure for Windows(tm) of the subclass, and handle subclassed messages in the new windows procedure. The new Windows(tm) procedure may then use CallWindowProc(3w) with _func_ set to the parent class's Windows(tm) procedure to dispatch the message to the superclass.

RETURNS¶

The return value is message dependent.

CONFORMANCE¶

ECMA- 234, Win32

IMPLEMENTATION¶

Declared in "winuser.h". Implemented in "dlls/user32/winproc.c". Debug channel "win".