³ Zip Chunker, (C) Copyright 1991, Scott Jibben ³
³ Version 1.02 ³
This is a list of the files that should accompany this software
ZC.DOC 12832 03-25-91 1:02am
ZC.EXE 14643 03-25-91 1:02am
ORDER.FRM 1936 03-25-91 1:02am
VER-HIST.TXT 2795 03-25-91 1:02am
This software has been compressed using PKLite Professional.
What this software does
This software will take an existing ZIP (tm) file that was created
using PKWare's PKZIP (tm) software and create subsets of the file
according to a users specified size. These subsets can be
uncompressed as normal using PKUNZIP (tm).
Requirements for Zip Chunker
Zip Chunker allocates memory as needed when processing. However, I
suggest that you have at least 200KB of free memory to run Zip Chunker.
If you are going to process large Zip files (with a lot of files, not
total size), I suggest that you have 350KB of free memory to run
It is relatively simple to install Zip Chunker. If you already have
the PKZip software installed and PKZip's location in your path statement,
all you have to do is add the Zip Chunker files into the same subdirectory
as the PKZip software.
If you don't wish to have the Zip Chunker software in the same
subdirectory as the PKZip software, all you have to do is set up a new
subdirectory for the Zip Chunker software, copy the Zip Chunker files
into that subdirectory, and then add that subdirectory to your path.
I won't go into the details of making subdirectories and modifying
your path as you should have good examples of this in your DOS manual.
The concept of Shareware
Zip Chunker is being released as a Shareware product. Shareware is
a marketing concept, in which you get to try out a software package
for a period of time. If you find that the software is useful
to you (you are still using it), you are obligated to send in a
registration fee for that software to the author.
Zip Chunker's trial period is three weeks. That means, once you
start using Zip Chunker, you have three weeks to decide whether or
not it is useful to you. If it is useful to you, please promptly
send in the requested registration fee. If it is not useful to you,
you are expected to delete it and stop using it.
Zip Chunker is fully functional. That means I haven't put in any
code into this software to cripple it or in any way make it
annoying to use. It simply does the job that you request it to.
There are a number of things that I could have put in this software
to make it annoying use and then promise that those aspects would
be removed upon receipt of a registered version. However, I'm
relying on the integrity of the people that use my software to
Here's what you get when you register my software:
1. Support. You can call and leave e-mail to me on any of the BBS'
listed in the Technical Support section of this document or
CompuServe and get a response from me. I will more than likely
answer all questions, but the registered individuals will
definitely get top priority.
2. Advance notice of my upcoming software products/upgrades. This
also includes the little fixes. It has always annoyed me when
I register Shareware software and then find out three months
later that there is a slightly newer version, that I never got
a copy of. Keep in mind that the extra auto-upgrade fee only
applies to major versions (1.x to 2.0, 2.x to 3.x, etc.)
3. Special access to new products. You will be allowed access to
beta test any software package that I'm in the process of creating.
The beta software will be available only on the Warehouse BBS
(see Technical Support section of this document for details).
Advantages of Using Zip Chunker
I've designed Zip Chunker to make the least demands on your
hardware. Zip Chunker is at least 2 times faster than any other
software package of this type. In some instances, I've found it to
be up to 10 times faster.
One other benefit from using Zip Chunker is the amount of disk
space it requires to process a ZIP file. My closest competitor
requires 2-3 times the disk space of the original ZIP file, ie, if
you had a 2MB ZIP file you would have to have up to 6MB of free
disk space in order to break it up! Zip Chunker requires the
amount of the original ZIP file plus 16KB for free space, ie, if
you had a 2MB file you would only need 2MB + 16KB free in order to
use Zip Chunker.
The algorithm in which I calculate the amount of files to put in a
ZIP chunk is highly optimized. Zip Chunker will sometimes have one
less chunk than other software packages of this type and the chunks
will be closer to the requested size.
Zip Chunker can handle any file created using PKZIP (tm). All other
software packages of this type that I've seen, have the tendency to
crash if the ZIP file is too large or there are too many files in
the ZIP file. One of my beta testers ran ZC on a 170 Megabyte Zip
file and ZC processed it without problems.
If you would like to be a distribution point for this software, I
would be happy to talk to you about the best way to get it to you.
Please send a letter or e-mail to me with your phone/BBS number on
one of the computer systems I have listed in the license screen (ZC
/L). These systems are also listed in the Technical Support section
of this document.
Using Zip Chunker
The software is fairly straight-forward and easy to use. In fact,
I doubt that you will need to read this document in order to be
able to use the software. Zip Chunker will always display all of
your options when you just type in ZC and press Enter. Below is an
example of what you will see when you do this:
Zip Chunker 1.02. Released: 03-25-91
Copyright 1991, Scott Jibben. All Rights Reserved.
Syntax: ZC [/L] | [zipfile [# | /5L | /5H | /3L | /3H] [/S]]
[/L] - License information.
[zipfile] - Name of Zip file to be sized.
[#] - Maximum size of the produced Zip files in bytes.
[/5L] - Maximum size = 5.25" Low Density Floppy Disk (360KB).
[/5H] - Maximum size = 5.25" High Density Floppy Disk (1.2MB).
[/3L] - Maximum size = 3.5" Low Density Floppy Disk (720KB).
[/3H] - Maximum size = 3.5" High Density Floppy Disk (1.44MB).
[/S] - Don't delete [zipfile].
The important line to note is the Syntax line. It contains the
basic information on what parameters can be used and in what order
they should appear. First of all, every parameter that is enclosed
in brackets  is an optional item. The "|" character means OR.
The best way to explain how it works is to give some examples, so
The example above will display Zip Chunkers license information.
C:\WORK\>ZC workdata /s
The above example will break out chunks from WORKDATA.ZIP that will
be equal to or smaller than the size of a file that would fit on a
3.5" HD disk. It will also save the original file, WORKDATA.ZIP.
C:\WORK\>ZC 123data /5L
The above example will break out chunks from 123DATA.ZIP and these
chunks will be equal to or smaller than what would fit on a 5.25"
low density disk. It will delete 123DATA.ZIP when it is done.
C:\TELIX\UL\>ZC e:\games\biggame 200000 /s
The above example will break out chunks from E:\GAMES\BIGGAME.ZIP
and these chunks will be equal to or smaller than 200,000 bytes.
The original file, E:\GAMES\BIGGAME.ZIP, will be saved as well.
Also, the new ZIP chunks will be created in C:\TELIX\UL.
Zip Chunker will not allow you to process a ZIP file if there isn't
enough free disk space available.
If Zip Chunker finds a file in the original ZIP file that is larger
than the maximum size specified, it will give you the option of
continuing to process the ZIP file. The result of this type of
operation is that there will be some ZIP chunks that have only one
file in them but they will still be larger than the maximum size.
If the original ZIP file is already smaller than the maximum size
then Zip Chunker will tell you and not process the ZIP file.
Zip Chunker will in most cases be able to detect that a file passed
to it is a valid ZIP file or not. It will not be able to detect if
the internal files have been corrupted, though. I plan to add an
option in a future version that also does CRC-32 checking as it
processes the Zip file.
Zip Chunker CAN handle password encrypted files and retain the
password in the ZIP chunks.
Zip Chunker was written entirely in C using Borland C++ 2.0. This
is a partial explanation of ZC's speed and size. The other main
reason for ZC's speed and size is that I have made great use of
dynamically allocated memory routines.
For technical support I can be reached at the following on-line
The Warehouse BBS: 612-729-0160 1200-38400 baud V.32bis/HST (N81)
The Warehouse is my first (main) line of support. Since I am a
co-sysop of this BBS, I usually log on several times a day to check it
out. This BBS is a subscription BBS, however anyone logging on
will receive access rights to the file area where my utilities can
be downloaded and a message area that is dedicated to my software.
My CompuServe ID is 72657,3303. Feel free to send me an E-Mail any
time. I usually log on to CompuServe at least once a day.
Nick's Nest BBS: 612-490-1187 1200-2400 baud (N81)
612-490-0341 9600 baud only (HST) (N81)
Nick's Nest is run locally to me and the Sysop is a good friend of
mine. This is also a subscription BBS (a mere $10 a year), however
you will have access to send me messages via E-Mail (message area 1).
Painter's Workshop BBS: 414-722-2069 1200-19200 baud (V.32) (N81)
Painter's Workshop is my Wisconsin connection. It is another board
that is operated by a friend of mine. Painter's Workshop is an
open BBS, you will have access to downloading and messages immediately.
I usually log on to this BBS 2-3 times a week.
I would like to thank those people that have assisted me in the
development of this software:
Chris Edmonson, who gave me some valuable insight on various
methods of designing the dynamic memory allocation code.
Travis Carter, sysop of the Warehouse BBS, for testing the software
and providing a message forum for supporting software written by
Chris Reagan (Painter), sysop of Painter's Workshop, for distributing
my software all over eastern Wisconsin.
Tom Black of McHenry IL, for finding a bug in version 1.0. See
VER-HIST.TXT for details.
My wife, for the patient support.
Scott Jibben specifically disclaims all other warranties, expressed
or implied, including but not limited to implied warranties of
merchantability and fitness for a particular purpose, functionality
or data integrity. In no event shall Scott Jibben be liable for any
loss of profit or any other commercial damage, including but not
limited to special, incidental, consequential or other damages.
Borland is a registered trademark of Borland International, Inc.
PKWARE, PKLITE, PKZIP and PKUNZIP are registered trademarks of PKWare