A quick note to bluethundr to explain whats going on here.

Perhaps the biggest difference between your program and CombatSquirrel's and simonm's is that they do not prompt for input, but instead read it from stdin. A program that prompts for input can only be used in one way. A program that reads text from stdin, does some work (expands acronyms) and writes out to stdout is useful on the unix command line. It can be used just like any other unix tool, and in combination with any of them.

See The Art of Unix programming, or any good unix book. Its not more work to learn the unix way along with the perl way - its less!

qq