Thank you, this is a good idea. I do have one "actual" logfile which may receive more lines than my various "result" files. In this case, since I always know I'll be logging, I can open that one once, and then only open the various "result" files when I have results to output, since I don't always use all of them in every child.

The more I think about this, the more ridiculously picky I think I'm being :) With a "big calculation, small result" printing out the result is way cheaper than calculating it anyway, so I shouldn't really worry about the extra open's...

Alan