This function returns the ID of the X11 window. This gives us a chance to manipulate the Emacs window from within a different program. Since the ID is an unsigned long, we return it as a string. If non- nil , synthetic events are allowed. With false, make it asynchronous.
Synchronous connections are much slower, but are useful for debugging.
Your backtrace of the C stack will now be useful. If device is not specified, the selected device is assumed. If non-zero, debug information about events that XEmacs sees is displayed. Information is displayed on stderr.