> Excuse my ignorance, but what is "argp" as mentioned by the GNU Hurd > Reference Manual? It sounds related to argc or argv but I can't figure out > what it is.
It is a set of library functions for parsing command line arguments in a highly modular way. It was originally written (by Miles Bader) for the Hurd, and is used extensively in the Hurd libraries and programs. However, there is nothing really Hurd-specific about it. It is now part of GNU libc (2.1 and later, on all platforms) and no longer in the Hurd sources. See the header file <argp.h>, and there is a section in the GNU libc manual that documents it.
