CWnd::OpenClipboard
BOOLOpenClipboard();
Return Value
Nonzero if the Clipboard is opened via CWnd, or 0 if another application or window has the Clipboard open.
Remarks
Opens the Clipboard. Other applications will not be able to modify the Clipboard until the Windows function is called.
The current CWnd object will not become the owner of the Clipboard until the Windows function is called.