A self-referential challenge

[Bennett Todd]

[
	Asks for suggestions on how to make 

		CRC-computer * >CRC-output

	contain correct CRC values for all files -- including
	"CRC-output"
]

That's easy, just iterate looking for the fixed point, like so:

	touch .CRC-output
	finis=0
	while test $finis -eq 0
	do
		CRC-computer * >CRC-output
		diff CRC-output >/dev/null && finis=1
		cp CRC-output .CRC-output
	done
	rm .CRC-output

But please, not on my machine:-). Seriously, without an in-depth analysis of
how CRCs behave (which is way, way beyond my abilities) there is no reason
to believe that a fixed point exists; it might fall into a cycle instead
(given any finite number of bits in the CRC, it has to do one or the other).
Unless some mathematician steps forward and waves her magic wand, I expect the
best answer will be to fall back 10 and punt:

	CRC-computer * | egrep -v CRC-output >CRC-output

I really liked the question, though.

-Bennett
bet at orion.mc.duke.edu