Hi, Bob.

BL>  RS> The same INPUT file, sure, clearly not the same OUTPUT file
BL>  RS> tho, the length was different. So the CRC should be different
BL>  RS> too.

BL>  FM> No. The CRC of a file within an archive is calculated on the
BL>  FM> data in the original file, not the compressed file, for all of
BL>  FM> the following: ARC, ARJ, LHARC, PAK, PKZIP, SQZ, ZOO and any
BL>  FM> compatible programs.

BL>   You've got him on toast with this one: an absoulute error in his
BL> understanding of how it works. I sincerely hope you'll save the
BL> original messages and hammer the little shit into the ground with it.

I'm sure I have the original messages, I keep most stuff where I'm
involved in the discussion. Maybe not the earliest ones from Paul/you
describing the problem, I think I joined in somewhat after the start.
But I don't see this as any different from most of the other discussions
with Rod - he's wrong, and I'll point out the facts if he wants to
listen. If not, he'll get abusive as usual and I'll drop the thread. As
usual.

BL>  RS> What was being discussed is if repeated rezipping of the SAME
BL>  RS> file can produce DIFFERENT zip files, different lengths, but
BL>  RS> with the SAME CRC. Its quite easy to see how repeated rezipping
BL>  RS> can produce a differently compressed file, most obviously with
BL>  RS> a different set of dictionary terms, but that WONT produce two
BL>  RS> files with the SAME CRC.

BL>  FM> Yes it will. See above.

BL>   If you don't want to give him a kicking, give him to keith.

Keith can have him. I'm not into kicking Rod when he's wrong, that'd be
a full-time occupation. :-)

BL>  RS> Sure, different say ram available could well produce that
BL>  RS> result, BUT that is very unlikely to produce the SAME CRC.

BL>  FM> From the same data it will, and that's what I think was
BL>  FM> happening. The one byte change was a different problem.

BL>  RS> Nope.

BL>  FM> Yes.

BL>   You've got him! He has no way out. keith will love it. I rather like
BL> it myself.

Take it away, Keith. :-)

Regards, fIM.

 * * Question and die, sayeth the CZAR!!!!
@EOT:

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