John Fremlin's blog: GNU is UNIX

The rebellious wildebeest GNU has somehow captured the essence of what UN*X is to many people. As Ted Dziuba amusingly notes, it is possible to do a great deal with UN*X that is difficult on other systems — in particular using the GNU extensions to standard UN*X utilities, like the -P argument to make xargs launch multiple programs in parallel.

Anybody who has used GNU utilities for a while and then logged onto a box running Solaris or one of the less dynamic BSDs has been frustrated with the limitations of the POSIX-standard versions of basic utilities like find.

The GNU coding conventions state

Avoid arbitrary limits on the length or number of any data structure, including file names, lines, files, and symbols, by allocating all data structures dynamically. In most Unix utilities, “long lines are silently truncated”. This is not acceptable in a GNU utility.

That might seem like basic common sense nowadays but these ideas were not standard practice in their time. Where would we be without --help from long options? Thanks GNU!