If i have a class name Class. The the function "Class" is called for every instance of the class when it starts, and "~Class" is class is called for every instance when it exits. My question is, is there a function that gets called only once when it starts, no matter how many instances of the class?

I ask this because im making a window into a class and in the constuctor i register the window class. I figure this might cause problems if theres more than one instance of the class. Or its just kind of a waste to register the window more than once.