A clipboard viewer window receives the WM_CHANGECBCHAIN message when another window is removing itself from the clipboard viewer chain. If the window being removed is the next window in the chain, the window receiving the message must unlink the next window from the chain. Otherwise, this message should be passed to the next window in the chain.
The following example shows the processing of the WM_CHANGECBCHAIN message.
case WM_CHANGECBCHAIN:
// If the next window is closing, repair the chain.
if ((HWND) wParam == hwndNextViewer)
hwndNextViewer = (HWND) lParam;
// Otherwise, pass the message to the next link.
else if (hwndNextViewer != NULL)
SendMessage(hwndNextViewer, uMsg, wParam, lParam);
break;