Unix Exit Status Code Reference

I always find myself constantly Googling the list of unix status codes (typically defined in `sysexits.h`).

0    # successful termination64   # base value for error messages64   # command line usage error65   # data format error66   # cannot open input67   # addressee unknown68   # host name unknown69   # service unavailable70   # internal software error71   # system error (e.g., can't fork)72   # critical OS file missing73   # can't create (user) output file74   # input/output error75   # temp failure; user is invited to retry76   # remote error in protocol77   # permission denied78   # configuration error