The MCIWndPause macro sends a command to an MCI device to pause playing or recording.
LONG MCIWndPause(
  hwnd  
);
 Returns zero if successful or an error otherwise.
  Windows NT: Requires version 3.1 or later.
  Windows: Requires Windows 95 or later.
  Windows CE: Unsupported.
  Header: Declared in vfw.h.
MCIWnd Window Class Overview, MCIWnd Macros