title: Keyboard catch in C
body: <p>So I'm thinking about how to catch keyboard activities in C. As we all know, we can type something and press Enter to stream in whatever we want to send to the computer. But the first question is, how to input some untypeable characters like up arrow, down arrow (especially these two guys because I'm using Linux but want to use them for something other than their default meanings), shift, ctrl or whatever. Second, how to make the program proceed right after we press any key, so we don't need to enter and enter all the time. (It's like "Press any key to continue" in Windows). </p>