Xref: utzoo comp.sources.d:2021 comp.binaries.ibm.pc.d:91
Path: utzoo!mnetor!uunet!husc6!uwvax!umn-d-ub!umn-cs!randy
From: randy@umn-cs.cs.umn.edu (Randy Orrison)
Newsgroups: comp.sources.d,comp.binaries.ibm.pc.d
Subject: Re: compressing compressed stuff
Message-ID: <5198@umn-cs.cs.umn.edu>
Date: 4 May 88 03:07:39 GMT
References: <292@cullsj.UUCP> <696@fig.bbn.com> <4744@teddy.UUCP>
Reply-To: randy@umn-cs.UUCP (Randy Orrison)
Organization: UofM Math Department
Lines: 29

This whole conversation has me puzzled.  Witness:

	pkarc:  If compressing a file (by any method) does not result in
		a saving of space, it is stored verbatim in the archive.

	zoo:	putting a zoo arhive into another zoo archive results in
		"0%" compression and the file getting only marginally larger
		(index information?)

	compress:	compressing a compressed file (e.g. a zoo archive)
		results only in wasting some time.  A .Z file is not created.
		(my test resulted in "-29.30% compression, file not compressed")

Summary:  all these methods of compression DO NOT COMPRESS if the result
would be larger than the original.  There is NO HARM in compressing a zoo
archive containing a pkarc of a binary file (except for the added index
information at each step).

The ONLY problem I can see in doing this is if the news software that does
compression isn't smart enough to check if the result is larger than the
original.  If it isn't smart enough, it should be.  There's no excuse for
not checking that simple condition.

	-randy
-- 
Randy Orrison, Control Data, Arden Hills, MN		randy@ux.acss.umn.edu
(Anyone got a Unix I can borrow?)   {ihnp4, seismo!rutgers, sun}!umn-cs!randy
The best book on programming for the layman is "Alice in Wonderland";
but that's because it's the best book on anything for the layman.