LOL IT'S C TIME

Hi /prog/, I have some experience with C, but I don't know how to do much except take text input, save variables, calculate, and print text out. What should I read to learn to do things like display graphics, save/load files, send/receive data using ports, et cetera?

[b]THIS IS /prog/
EVERY [b[[i][o][u]BBCODE FAILURE[/i[[/b][//u]{o] WILL BE POINTED OUT
NO EXCEPTION[/b]