This is in keeping with the style of the original Unix utilities. Having a handful of global variables reduces the amount of stuff being passed around from fun

This is in keeping with the style of the original Unix utilities. Having a handful of global variables reduces the amount of stuff being passed around from function to function; utilities don't need to worry too much about free()ing dynamic allocations, since that gets cleaned up on exit anyways; none of the code has to be re-entrant, because each invocation of the utility is running in its own process.