This function returns 1 (True) if the system owns the specified format on the clipboard. If format is omitted or empty, then the standard clipboard text format is assumed and the function returns 0 (False) if either Arbortext Editor's default paste buffer is not empty (meaning Arbortext Editor owns the clipboard) or the system clipboard is empty. If the set selectionsvc option is off, this function always returns 0.

This function will return 0 if called from a paste callback function when format is omitted or empty, since at that point Arbortext Editor owns the clipboard.