The WM_CHANGECBCHAIN message is sent to the first window in the clipboard viewer chain when a window is being removed from the chain.
WM_CHANGECBCHAIN
hwndRemove = (HWND) wParam; // handle of window being removed
hwndNext = (HWND) lParam; // handle of next window in chain
If an application processes this message, it should return zero.
Each clipboard viewer window saves the handle of the next window in the clipboard viewer chain. Initially, this handle is the return value of the SetClipboardViewer function.
When a clipboard viewer window receives the WM_CHANGECBCHAIN message, it should call the SendMessage function to pass the message to the next window in the chain, unless the next window is the window being removed. In this case, the clipboard viewer should save the handle specified by hwndNext as the next window in the chain.
Windows NT: Requires version 3.1 or later.
Windows: Requires Windows 95 or later.
Windows CE: Unsupported.
Header: Declared in winuser.h.
Clipboard Overview, Clipboard Messages, SendMessage, SetClipboardViewer