It's maybe the right thing, but not the obvious thing. In the context of DOS assembly language programming, the only obvious thing is "nothing". DOS is barely

It's maybe the right thing, but not the obvious thing. In the context of DOS assembly language programming, the only obvious thing is "nothing". DOS is barely an OS, it's mostly a library of function calls. DOS does nothing most of the time, so you expect it to do nothing all the time. At the time I didn't yet spend a lot of time doing DOS assembly language programming, but since then I did, and had I heard about this for the first time today, I would be really surprised.