>> What type is add expecting and what is it going to return? Not only that. Can I keep the thing that is returned, can i save it for later, can i change it an

>> What type is add expecting and what is it going to return? Not only that. Can I keep the thing that is returned, can i save it for later, can i change it and not affect other parts of the program, is there someone looking at the same part of memory ? All kinds of worrisome questions spring to mind.