CLIgen is a Command-Line Interface generator written by Olof Hagsand.

Well, actually it is not really a generator, since it does not generate code
for CLI's. Instead, it builds and interprets datastructures (a parse-tree)
which a library (libcligen) interprets in runtime. It is fast and efficient
and helps you develop CLI:s easier. You enter a CLI syntax either in a text
file, you write callback functions where you call the right library routines.
The callback functions add the semantics, that is, what the commands in the
CLI are supposed to do.

WWW: http://cligen.se/