According to the Allegro website
"Allegro is a game programming library for C/C++ developers distributed freely,
supporting the following platforms: DOS, Unix (Linux, FreeBSD, Irix, Solaris, Darwin), Windows, QNX, BeOS and MacOS X.
It provides many functions for graphics, sounds, player input (keyboard, mouse and joystick) and timers.
It also provides fixed and floating point mathematical functions, 3d functions, file management functions, compressed datafile and a GUI."