peek() can currently not be used there since it doesn't exist on Windows (that ought to be fixed, though).
Fixed.
Great! Is it tested?
Not yet. The change was minimal (prefix select() with fd_ (all the other operations were already prefixed), and remove the #ifndef __NT__). It compiles, and I don't see any reason why it would work any worse than on the other select()-based peeks (ie the BSDs).