"inport and outport functions if your operating system is dos (or windows)"

Direct hardware access (inport and outport) is deprecated on Win95 and later.

Win32 can humour some applications, and let them think that they're talking direct to hardware - but they aren't really, and you're likely to come unstuck.

Borland C++ Builder doesn't even have the inport and outport functions functions any more! :-(
I expect MSVC is the same?