Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!gumby!obryan
From: obryan@gumby.cc.wmich.edu (Mark O'Bryan)
Newsgroups: comp.sys.atari.st
Subject: Re: packer.arc
Message-ID: <811@gumby.cc.wmich.edu>
Date: 1 Aug 89 00:13:33 GMT
References: <575@prles2.UUCP> <15290@watdragon.waterloo.edu> <4433@druhi.ATT.COM>
Organization: Western Michigan University, Kalamazoo, MI
Lines: 23

In article <4433@druhi.ATT.COM>, terrell@druhi.ATT.COM (TerrellE) writes:
> 
> How does "packer" work???  I understand that it reduces the size of
> the program file, but when the program runs, is more memory available???

No, it isn't magic, and more memory isn't available at run time.  There
appears to be a couple hundred byte "unpacker" at the front that expands
the object code back to it's original size at run time.  From some tests
that I've done, it does this at about 250 kB/sec, which means you probably
won't pay any performance penalty unless you're running from a RAM-disk.

So far, all I've packed and use regularly is the Micro C-Shell and Tools.
I haven't had any problems so far, but do wonder how reliable and bullet-
proof "packer" is.  It certainly seems to be a nice way to turn a 20-meg
drive into a 30-meg drive.

I'm disappointed that "packer" didn't come with more documentation.
I'd feel a lot more comfortable knowing more about its heritage.

-- 
Mark T. O'Bryan                 Internet:  obryan@gumby.cc.wmich.edu
Western Michigan University
Kalamazoo, MI  49008