Return to the Article Index
Return to the Main CD Index

Graphic Interpretation - Conversions
by Bruce Thomas

Commodore users have always done what they could to help others get the most out of their computers. This camaraderie was evident early on with the formation of User Groups containing lots of people with various skills and interests. However, our Commodore Community has always been larger than local User Groups.

The Community was able to come together through the use of a variety of telecommunications services. These services ranged from local BBS's to the large national services like Genie, CompuServe and Q-Link. Through services such as these it was possible for Commodore Users equipped with modems and terminal programs to share information and knowledge and, most importantly, files and software. The arrival of GEOS, with its proprietary file storage format, threw a few kinks into the file sharing process.

Catch-22

The GEOS file format includes an Info block that contains the Author info, file Icon and comment field among other things. This block is not part of the program file itself but sits separate on the disk. The Variable Length Indexed Record (VLIR) format of GEOS files also contributed to the lack of ability to transmit the files in their native format.

In order to allow users to share GEOS files and programs a conversion process was required to change the file format into a normal Commodore Sequential or Program storage scheme. Bill Coleman developed the Convert program that has become a standard for GEOS users but there was a Catch-22 involved.

Since Convert itself was a GEOS program it could not be uploaded to a telecom service and would be restricted to transfer among users on diskette only. To get around this, a version of Convert was created in Basic loader form that would create the GEOS Convert file on a user's disk. This loader version meant that Convert could then be distributed to many users via the previously mentioned transfer methods.

Convert went through many versions with the last one being Convert 2.5 (5/7/89) that comes in both program and Desk Accessory versions. Convert 2.5 allows the user to select multiple files for conversion at once to make the process quicker.

Luggage

Have you ever taken a trip on a plane or a train and had to check your luggage? How much work is involved if you have more than one bag? How much stress is involved in keeping track of the multiple bags and hoping they all arrive at the destination with you?

Although the Convert process worked very well to allow files to be shared there was the problem when having to transmit many files. Wouldn't it be nice if you could stuff all of your files into one nice and neat carry-on bag?

Bill Lucier wrote Wraptor and it is available from LoadStar as a freely distributable program. Wraptor is not a GEOS program but it handles the conversion and packing of GEOS programs with great ease. Files created with Wraptor end in .wr3.

Errol Smith's UnZip is another non-GEOS program that allows GEOS users to have access to files stored in ZIP format. The Zip format is popular in the PC world and compacts and combines many files into one easily transmitted file. This was the first program that let us unZip files directly on the Commodore.

GEOS Gems

Spike Dethman was a GEOS innovator and he brought us lots of great programs on his GEOS Disk 1. GeoPack (11/3/93) is the program we are interested in right now and it solves the biggest problem with Convert. It is possible to choose multiple files with geoPack and have them converted and packed into one file for easy transfers. Files created with geoPack default to a name ending in .lnx.

GeoConvert 98f (04/25/99) is a great program from Markus Kanet (adapted to 80 columns by Wolfgang Grimm) and it handles lots of conversions for us. Among the many conversions it handles are GEOS to Commodore format and vice-versa, Sequential to UUEncoded format and vice-versa, D64 files to disk or file and disk to D64 and it also splits Sequential files and rejoins them.

Todd Elliott is continuing his attempts to bring new functionality to GEOS users by creating GunZip. This GEOS program lets users unZip files while remaining in the GEOS environment. Presently this program is being Beta-tested and is not available for general use. Some nice features include the automatic conversion back to GEOS format for any files included in the ZIP file. At present there is no way to create ZIP files on the Commodore but Todd is planning on adding that to GunZip. Todd is using Pasi Osala's UnZip routines (http://www.cs.tut.fi/^albert/). If you are interested in Todd's GunZip be aware that it requires a SuperCPU and the Wheels Operating System.

Last but not least is GeoDOS. This workhorse of a program converts files from GEOS format to CBM format for one thing and it can read and write to PC formatted floppies. For anyone wishing to transfer files to the PC platform geoDOS also converts geoWrite docs to PC format.

All of these programs should be a part of every GEOS Users' file library as they bring much needed functionality to the system and make our computer use more productive.

Until next time, enGEOy your Commodore.