[olefoo]

The whole 'useless use of cat' meme is basically designed to let Randal Schwartz make fun of people. At one point it may have made a difference, and certainly if you have a shell script that is getting called 10,000 times a day it might make sense to optimise it. But for doing stuff from the commandline; weird shell acrobatics is a premature optimisation.

[jrockway]

The whole 'useless use of cat' meme is basically designed to let Randal Schwartz make fun of people.

So true.

My requirement for a shell command is that it be reasonably easy to assemble, return something resembling the correct answer, and that it run in a reasonable amount of time.

If your requirements are more strict than those, it's time to write a real program.