Path: utzoo!attcan!uunet!deimos.cis.ksu.edu!ux1.cso.uiuc.edu!uwm.edu!lakesys!mikes
From: mikes@lakesys.lakesys.com (Mike Shawaluk)
Newsgroups: comp.sys.amiga
Subject: Re: Archive idea (was Re: Self Extracting Archives)
Message-ID: <1749@lakesys.lakesys.com>
Date: 15 Mar 90 22:31:30 GMT
References: <55.25f441b5@uoft02.utoledo.edu> <195@sai.UUCP> <2675@leah.Albany.Edu> <79.25f87ef0@uoft02.utoledo.edu> <10102@cbmvax.commodore.com> <90.25fc5fd6@uoft02.utoledo.edu> <13763@nigel.udel.EDU> <6910@cps3xx.UUCP> <495@telxon.UUCP>
Reply-To: mikes@lakesys.UUCP (Mike Shawaluk)
Distribution: na
Organization: Lake Systems - Milwaukee, Wisconsin
Lines: 55

In article <495@telxon.UUCP> davidw@telxon.UUCP (David Wright) writes:
>	I think that's great! Everyone seems to be overlooking the WORST
>aspect of self-extracting files.
>		They make you waste your time DLing extraction code
>		you probobly don't need
>If you dl 5 things, each with the extraction code, you have just wasted
>5*x amount of disk storage, time, etc. I suspect most people will prefer to
>use the extraction program, rather than trust self-extraction, and for those
>people, the self-extraction code is a waste. For the others, they simply
>need to learn the basics of operating a computer. If they don't like having
>the archiver handy, it's better that (maybe) 5% of the people are inconvienced
>instead of 95% wasting their time...

I know that this is probably on the verge of flogging the proverbial dead
horse, but from my understanding, the MAIN reason for having self-extracting
files is to be able to extract the first program you get, when you don't have
an extracter handy yet!  For example, it's kinda tough to extract PKAZIP.ZIP,
if you don't have PKAZIP yet, or even PKAZIP.ZOO or PKAZIP.LZH or ...
whatever.  If, however, the program PKAZIP.PAK were available, it could be
downloaded, and would self-extract upon its name being typed (assuming, of
course, that it wasn't padded or otherwise lengthened in size during the file
transfer).  Since the old PAK program always made files multiples of 1K long,
this was usually not a problem (nowadays, where most people are using
"smarter" file transfer protocols that preserve the file size, date, etc.,
this issue is fading away; I've never even used the "auto-chop" option on my
current terminal program).

Historically, the first usage (that I know of) for self-extracting files was
with distributions of SEA's ARC program for the IBM PC.  Since each version
that was being introduced was using new compression methods, which were
incompatible with the previous version of the program, one couldn't guarantee
that an update would be able to be unpacked by the previous version, unless
that file were compressed with the old version of the program, which, in many
cases, made the file much larger than it would have been than if the newer
version had been used.  But by tacking on a self-extractor (which was based
on the newer algorithms), the program could be unpacked, and the savings in
space by using the newer compression methods more than offset the cost of
tacking on the self-extraction code.  In the case of PKZIP for the IBM PC,
there is virtually NO wasted space, since the self-extraction code that's
present can be plucked off the front of the original file via a small (896
byte) program, and the resultant code can be used by the user to distribute
their own self-extracting files, if desired.

I agree with the consensus that there is no need (or desire) for the majority
of file collections to be self-extracting; this takes up extra space on both
the sysop's computer and on my hard disk.  However, for "starter kits" and
distributions of packages via other means, including self-installing
programs, this capability can be very useful.

  - Mike
-- 
   - Mike Shawaluk             
"Rarely have we seen a mailer  ->  DOMAIN: mikes@lakesys.lakesys.com 
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