Lastly, we need a file of conventions in C files. The first C convention is that we are using the conditionals: #ifdef __linux__ for linux #ifdef __MACH__ for Mach #ifdef __BSD44__ for BSD44 #ifdef __NetBSD__ for NetBSD ONLY #ifdef __FreeBSD__ for FreeBSD ONLY #if defined(__linux__) || defined(__BSD44__) as a more complex example for code that runs on linux & NetBSD #endif /* XXX */ to end a conditional iff it is several lines. XXX would be __linux__, __MACH__, etc