Some of that ZIP stuff is really pretty slick. I remember once when I
worked in OS/2 land deciding to tackle the problem of software
installation performance from diskettes. One problem was that the
software couldn't read and decompress the files as fast as the drive
could deliver the data. That allowed the drive to stop spinning and
there was a hardware penalty of some largish number of milliseconds to
get the disk back up to speed. I defeated that easily enough by just
hitting the disk frequently enough to keep it running even if I couldn't
use the data. Then I worked on the compression algorithm using a
heavily modified form of LZW (like most everybody else) and was
successful in getting compression times and ratios that were much better
than the (original) PKZIP but lagged it by about 20% in decompressing.
But since decompression time was the true goal the experiment was not
completely successful. Of course, I didn't really have to beat PKZIP.
What I had to do was decompress a sector from the diskette faster than
the drive could deliver another one. Try as I might I couldn't get an 8
or even 10 MGHz 80286 to keep up with the drive. Eventually, processor
speed and memory for buffer space made the problem moot but, to this
day, I still wonder how PKZIP was able to beat me by 20%. Is PKZIP
still around?
Chuck Norcutt
Garth Wood wrote:
> Moose wrote:
>
> [snip]
>
>> And for those of us so backward as to be using Windoze, the Windows
>> Explorer will extract zip files. You have to actually double click on
>> the zip file in XP. In Vista, the contents are automatically shown, as
>> though it were a folder, and there is an extract button up top.
>
> Moose is correct, of course -- I've just never been able to bring myself
> to trust that XP will do the unZIPping part correctly. ;-) (FreeZIP
> also ZIPs stuff up for me, which XP doesn't do particularly efficiently,
> either).
>
>
> Garth
>
> ==============================================
> List usage info: http://www.zuikoholic.com
> List nannies: olympusadmin@xxxxxxxxxx
> ==============================================
>
>
>
==============================================
List usage info: http://www.zuikoholic.com
List nannies: olympusadmin@xxxxxxxxxx
==============================================
|