I have a Mac, so I don't have access to any windows.h functions, or any other windows libraries in C++. I am creating a game in C++. The controls of the game are the characters w,a,s,d. Currently I have the input method as std:cin. However, the problem is after the user types each character they must hit enter every time. Furthermore, the fact the std::cin does not timeout means that the user can essentially 'pause' the game to think about what move to make next (which ruins much of the fun of this game). 

I need a function like std::cin but with a timeout of about .25 seconds. A function that will return as soon as the user types the character (without the need of the user hitting enter) would also work; but a function like std::cin with a timeout would be preferred. Please don't suggest window's library functions as I am again a Mac user using terminal. 

Are there any standard c++ functions within the standard mac Libraries which will function equivalently to std::cin with a timeout of T that will run correctly in a Mac terminal?