What is it that you think blocks the system? I write console apps all the time w/ the std lib and I've never had trouble running other stuff on the desktop at the same time. If a console app doesn't have the focus, it can't block the system. I've never even tried making a console app modal, but I guess if you can do that you could force it to block the system in the same sense that any modal window blocks other windows. Other than that, I don't think you have anything to worry about. Are you experiencing some specific problem?