I've also read in Perl books how great it is, so that a script that takes a "file name" argument can actually do all that stuff.

The two don't really relate that strongly... For security's sake you need to parse and verify the filename param to the script before handing it to open anyway. A design making it easy to pass unverified user input to potentially destructive syscalls is just inviting trouble.

But then, I think we agree for the most part. We both seem to like the 4th argument hash idea. ;-)

-Blake