Decoded: GNU Coreutils
I’d categorize the variants in three groups: trivial, wrappers, and full utilities
Trivial utilities have a unique set up phase which defines a macro in a couple lines. Examples include: arch, dir, and vdir
Wrappers perform setup and parse command line options which are passed directly as arguments to a syscall. The following code lines occur in most non-trivial utilities:
This header defines system-dependent marcos, variables, and functions.