Unzip64v2.00
------------
Copyright 1998 Errol Smith
This is the first public release
version of Unzip64v2, a program to
decompress 'zip' archives created by
PKZIPv2.04g or equivalent programs. It
will work on a c64 or c128 in 64 mode.
This program is free to be distributed
as long as it is unmodified in it's
original archive, using the original
filename. (UNZP6420.PRG)
NOTE The file is a self-extracting-zip,
-not- a 'normal' c64 program. Please do
not compress it with something else!
(you won't gain much if you try)
If you find the program useful, I
would appreciate some encouragement to
continue development. A donation of $10
(or more! (-: ) is suggested, though a
simple apreciative email/letter will
suffice.
I would also be happy with donations
of software (eg. if you are a software
author or distributor), or hardware (a
128 would be nice, as would utility
carts - AR, FC etc, or any CMD device).
If you would like to donate some of the
above please contact me in advance.
Anyone making a healthy contribution
will recieve acknowledgement in this
documentation as well as on my web
page.
I would like to thank all the people
that helped beta test the program and
provide feedback & suggestions -
particularly those that supplied me
with zip files causing the program to
break. Without those zip files tracking
down the bugs would have been next to
impossible.
Though this is a public release, the
program is far from finished, though I
am confident that most bugs have been
ironed out. (still got wrinkles though)
Contact Information
-------------------
The latest news & updates of unzip64v2
can be found on my 64 web page at:
http://www.ros.com.au/~errol/64.html
Internet e-mail: [e-mail]
Fidonet Netmail: Errol Smith
3:712/523.5
I can also be contacted in any of the
Fidonet CBM, CBM-128 & CBM-GEOS echoes.
Snail Mail:
Errol Smith
PO Box 119
Round Corner
NSW 2158
Australia
Important Notes
---------------
* This program is still in development,
and may still contain bugs. It does not
have much in the way of error checking,
and may crash or act unpredictably. Any
bug reports & suggestions for
improvements are welcome. If reporting
a bug I would apreciate being sent the
zipfile that caused the error (if the
zip file is valid).
* Unzip64v2 cannot decompress ZIP's
created by PKZIP1.xx. You will need to
use Bill Lucier's Unzip64 or David
Schmolls NZP128 package to decompress
these files. (the exception to this is
if the files are all stored, but that
is unlikely).
If Unzip64v2 says 'UNSUPPORTED!' when
unzipping then you probably have a
ZIP1.xx archive.
* I have changed the version convention
since the beta testing to unzip64v2.xx
where 2.xx is the revision number,
starting with 2.00 with this initial
release. Don't get confused.
* If you posess or know of any beta
versions of unzip64v2, please delete
them. This is especially true of any
publicly available versions (eg on BBS
or FTP sites). -ALL- the beta versions
have bugs and should be eliminated.
* The distribution archive -IS- a self
extracting zip archive. Unfortunately
the code is custom written for this
package and isn't publicly useable.
There are severe practical limitations
to using zip for self extracting files,
so don't expect a publicly usable
'SXZ' (??) module in the near future.
I didn't call the distribution an SFX
as it would be confused with LZH SFX
files. I propose the extension 'SXZ'
for future Self eXtracting Zips. Any
comments?
Main Menu
---------
Most options are reasonably self
explanatory but I'll detail them anyway
to help stop any confusion.
F1 - Shows a directory of the input
device, using the source path.
F2 - This toggles the input device
number. This is the device that
the source zip file is on. It
should automatically find the next
valid device on your system. Valid
device numbers are 8 through 30.
+ - Change the source path. This is
only of use to users of CMD type
devices, and allows you to set the
partition & subdirectory for the
source zip files. The path you
enter is pre-pended to the input
file verbatim. It MUST include a
trailing colon!
F3 - Shows directory a of the
destination device, using the
destination path.
F4 - Toggles the destination device
number (where the extracted files
will go). Similar to F2.
- - Change the destination path. This
is where extracted files will go.
See notes above about source paths
& remember the trailing colon.
F5 - Set zip filename. Allows you to
change the name of the input file.
F6 - Toggle the default output file
type - P (PRG) or S (SEQ). This is
the file type that extracted files
will have. Note you can manually
override this with individual
files.
F7 - Unzip a file. This starts
unzipping the specified file. See
'Unzipping' later on for details.
q - Quit unzip64v2.
Generally to use unzip64v2, you set
the appropriate source & destination
devices (and paths if needed), set the
zip file name with F5, then start
unzipping with F7.
UnZipping
---------
Unzipping handles files within the zip
archive one at a time. As each file is
processed, the filename will be
displayed, followed by a query with
options [ynqaps]. Each letter means the
following:
y - Extract this file using the default
file type.
n - Do not extract this file & skip
to the next one.
q - Quit unzipping & return to the menu
a - Extract this file and ALL remaining
files without further prompts,
using the default file type.
p - Extract this file as a PRG file,
regardless of the default type.
s - Extract this file as a SEQ file,
regardless of the default type.
Simply press the letter of the option
you want.
The screen border will flash during
inflating - this is debugging info for
myself, plus it lets you know that
something is happening when inflating
files.
Please ensure there is adequate disk
space on the destination drive before
beginning!
Past, Present & Future
----------------------
This program has been in development
part-time for over 2 years (since late
1995). I began the project primarily as
a self-education on compression theory.
It was also a shift from my previous C=
experience which was almost entirely
demo-coding.
The program code is based partly on
publicly available C source
(eg. Info-Unzip) along with many other
sources of information on compression
theory, and the deflate algorithm.
Unzip64v2 uses approximately 35k of
memory during decompression. 32k is
used for the sliding dictionary, and
the remainder is used for the various
huffman tables. The deflate code itself
is approximately 2.5k, plus various
look...