CP/M - The Lost Operating System
By Grant Kwai
Copyright (c) 1992 Apple Users' Group, Sydney
Republished from Applecations, a publication of the Apple Users' Group, Sydney, Australia.
First, there was the invention of electricity. Soon after, many say, CP/M was born. Yes, CP/M is that old archaic operating system, which so many have long forgotten about. Has CP/M totally bitten the dust though? The Microbee still uses it, you can run CP/M on your Apple, Commodore 128 and there are thousands of stand alone CP/M systems still working out there even now. Some say that MS-DOS is a descendant of CP/M. Much of the functionality and commands are very similar.
Apart from the 5000+ dedicated CP/M programs floating around the archives, I have recently found a new use for my CP/M card on my Apple. Since much of the commands under CP/M are so similar to MS-DOS, many programmers have programmed, programs (talk about alliteration!) which can convert MS-DOS packed packages to the CP/M environment.
For those of you who are lost, when transmitting programs via a modem, we normally 'pack' or compress several programs into one smaller file. This makes what we have to send smaller and hence faster (See my reviews of Shrinkit and Disk disintegrator Duluxe in previous Applecations magazines).
Does this mean that we can now run MS-DOS programs under CP/M? No. What we can now do however, is unpack text files, or ASCII files from an MS-DOS packed file to CP/M.
Since there is practically gigabytes of information as text files on Bulletin Board Systems, you can imagine how invaluable such a program could be.
Resulting from the fact there are many packing programs on an IBM machine, there is similarly many types of unpackers available. The main types now being LHARC, UNARC, UNZIP. These are generally defined by the suffixes of LZH, ARC, and ZIP respectively.
I find the easiest way to convert a file that you want from a BBS is to download it with your normal ProDOS based modem communications package (e.g. Proterm, Talk is Cheap etc), change the file type to BINary if necessary and then use a program which can convert it over to the CP/M environment (e.g. Chameleon). Once in the CP/M environment, it is then a simple matter of running the program to extract the textfile/s.
If there is one thing that disgruntles me about the extracting program is the way in which you have to manually type everything out step by step. It is very user unfriendly. Unlike most Apple programs which at least offer the use of a menu and ask questions one at a time, most CP/M programs do not do this. This seems to have been carried on, onto the MS-DOS operating system as well.
Take for example, you want to extract all the files from a compressed file. First, you would need to run a separate program to view the files in the package. You would then need to run a specific program which could extract that file. What you would need to type though is something like: A: UNARC B:filename.LZH C: *.*
First you have to define which disk drive the UNARcing program is in (A:= drive 1). Then you have to define the packed file name with suffix, then you have to define the location of the destination drive and the file name and type (*.* means that it will extract it to whatever the original filename and type were before being compressed).
There is no certainty that this will work though. Some programs such as UNZIP must have all the files on the one disk (i.e. the unzip program, the compressed file). It will make the same disk the destination disk when extracting the files.
This could pose a problem if you have a large file to uncompress. To overcome this, I find using a ramcard set up like a hard drive (acting as a C: drive) works fine. It is also faster than disk access. Once the files have been extracted, use a program like NSWEEP to copy the files from the ramcard to normal disks.
Once on normal disks (e.g. 5.25" disks) you can convert them back to ProDOS for easier and more flexible data storage. ProDOS offers much flexibility in editing and viewing files which such programs as Appleworks, FrEdwriter etc. There are only a handful of these programs under CP/M which I have seen and most of them seem difficult or too involved to learn (e.g. Wordstar).
In conclusion, CP/M is by no means 'dead'. While programs which can extract IBM archives still exist, and people use them (How ever awkward they may appear compared to an apple), CP/M will continue to keep afloat in a world which is intoxicated with new technology every day. You will never realize how friendly the Apple environment is until you look at the extremes other operating systems exist on.
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