Decoded: GNU Coreutils

I’d categorize the variants in three groups: trivial, wrappers, and full utilities

Trivial utilities

Trivial utilities have a unique set up phase which defines a macro in a couple lines. Examples include: arch, dir, and vdir

Wrapper utilities

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.

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