104 lines
5.5 KiB
Plaintext
104 lines
5.5 KiB
Plaintext
Matthew Palcic
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1030 Dayton-Yellow Springs Rd.
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Xenia, Oh 45385-9508
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"Why Live In The Past?"
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In his article "Why Change What Works?" (PC World, Sep 89), Hal DuPrie
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shows a very biased comparison of ARC and PKZIP. SEA did sue Phil Katz,
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which DuPrie fails to mention was a major blow to the shareware world.
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Regardless of the fact that many people stopped using ARC because of
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that suit, ZIP was an instant success in the bulletin board world.
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Comparing ZIP to ARC, DuPrie states that ZIP has only slightly better
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(by 5 to 10 percent) compression. I have found that the Beta version of
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PKZIP v1.0 usually beats ARC by at least 15 percent. It's inefficient
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to maintain files on a bulletin board in multiple formats. So why not
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convert all the files to ZIP files (as many bulletin boards are doing).
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The question of keeping track of multiple file formats is easily solved
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by a number of shell programs that detect which compression format was
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used and what program will uncompress the file; no problem for novices.
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I called PKWare and was informed that both an Amiga and VAX VMS version
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are under development and should be released by the end of the year.
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However, ZIP lacks the machine support that ARC has. I would score ARC
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a point over ZIP in that respect. ZIP 0, ARC 1.
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The source code for ARC was released only YEARS after the program had
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been on the market, and the ARC format still belongs to SEA. However,
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Phil Katz has released the algorithms for ZIP compression and generously
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released the ZIP format into the public domain. Several programmers
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have released source code in both Pascal and C for creating/extracting
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ZIP files. That code can be ported to other machine formats as easily
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as the source to ARC. Shareware and public domain authors need not worry
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about infringement on any utilities they write for ZIP. The ZIP
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format's public domain status scores ZIP 1, ARC 1.
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ZIP is reliable. Phil Katz enjoyed a healthy success with PKARC, so his
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reputation carries on in ZIP. The code is no more bound to be
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bug-ridden than ARC. The ARC 6.02 manual (p.28) reads "Version 6.0...is
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a substantial rewrite..." Why would a 'substantial rewrite' of ARC be
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any different than changing PKARC into PKZIP? In fact, ARC 6.02 failed
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to handle shared files at all (program aborted) where PKZIP and PKARC
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both correctly handled the situation. ARC 6.02 also does a poor job of
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housecleaning if the program aborts. A very large temporary file and a
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zero byte file remained in the directory after using Ctrl-Break. I
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won't count the rewrite against the new version of ARC. But it should
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be of concern to heavy users of ARC. However, the incorrect handling of
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shared files is of concern to network users. ZIP 2, ARC 1.
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The remark about keeping both ARC and ZIP on a system for compatibility
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is rather meaningless. The savings ZIP offers definitely earn its keep.
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Whether having both programs on a system would "...probably take up more
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space than the savings..." is beside the point and is relative only to
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the price of eggs. In fact, for those users that do not require
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compatibility (for instance users that do not log onto bulletin boards)
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ZIP is the clear winner because of its better compression. ZIP 3, ARC 1.
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ARC is no more compatible with ZIP than ZIP is compatible with ARC. ARC
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is not compatible with anything but ARC. If it had not been for SEA
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suing PKWare, a newer PKARC would probably still be compatible with
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PKARC. However, that is a moot issue that arose entirely because of the
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law suit. Somehow ARC is now compatible with the so called 'Deviant'
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Squashing method used by PKARC. Is it coincidental that this happened
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after SEA gained the rights to the source code for PKARC? For that I
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score against SEA, and software consumers should be aware that SEA still
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has the option to sue any of their other competitors. ZIP 4, ARC 1.
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Moreover, I find ARC no easier to use than ZIP. A command line
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interface can hardly be considered 'comfortable.' Any of the popular
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shells in the BBS community can make either utility equally friendly.
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That's honest. Neither program scores a point for their 'interface'.
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Finally, I see Phil Katz as the Steve Jobs of compression programs. He
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came up with some innovative ideas for PKARC and came through again with
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PKZIP. And he even sells ZIP for less than what SEA sells ARC. The
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expandability of the ZIP format shows it will be around without change
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longer than ARC was without change. ARC now offers better flexibility
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and marginally better compression than previous versions, at the expense
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of compatibility. Darn the luck. ZIP will become the de facto standard
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and replace ARC, as major bulletin boards (such as Exec-PC) and on-line
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services (such as CompuServe) support ZIP. ARC will continue to follow
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in the footsteps of ZIP.
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---------------------------------------------------------------------------
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Compression results:
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5,518,337 bytes, consisting of over 2 megs of Pascal source code and
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over 2 megs of binary .EXE files resulted in the following:
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Program Compressed Ratio
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---------- ---------- -----
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ARC 6.02 3,215,042 41.7%
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PKARC 3.61 3,092,035 43.9%
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PKZIP 1.0á 2,419,261 56.1%
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---------------------------------------------------------------------------
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Matthew Palcic is a Computer Engineering student in Dayton, OH and is
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the author of several shareware programs including DynaBoot.
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