I wrote that sort of code on those sorts of platforms ;) The bigger problem was code that assumed INC/DEC was atomic and broke when the first multi core CPUs c

I wrote that sort of code on those sorts of platforms ;) The bigger problem was code that assumed INC/DEC was atomic and broke when the first multi core CPUs came out. Everyone knows/knew that a sequence of instructions can be interrupted with multiple OS threads and preemption. So I don't think I'm missing that. INC/DEC give you flags but they don't give you a copy of the value. But you still need to LOCK INC or LOCK DEC for your code to be multi-core safe. And if you're sharing values you need something like "test and set" or a kernel synchronization object. EDIT: I was basically saying the comment above that was correct because the comment I was replying to seemed to suggest it wasn't. But I guess both of them are correct and we're all in agreement ;) EDIT2: So really I agree that InterlockedIncrement/Decerement were designed for multi-processing use case since they basically offer no advantage for a single core over just inc/dec (++/--) this is what the comment above the one I was replying to (gp?) was implying and the person responding to that seemed to think otherwise ;) but I think we still found out we all agree.