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DOS code in CP/M? Revisited...

EvanK

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Did MS-DOS use code copied from CP/M? Forensic software engineer Bob Zeidman said "no" in 2012 but now he has new research to disclose at VCF West.

That's all I can say for now. :)
 
I'm a bit skeptical. SC-DOS seems to use CP/M 2.2 as its basis (COM programs can issue system calls by doing a far call to CS:0005 and putting the request number in CL; this is very different from CP/M-86's conventions. So you're trying to compare a bunch of 8086 code with 8080 code? That's a pretty far stretch.
 
Microsoft was sued when they pirated DOS through a third party.

They settled with IBM paying cash settlement on Microsoft's behalf and agreeing to sell CP/M-86 for PC's.

Of course they were selling it for $250.00 a unit ;-)

So no CP/M has no DOS code but DOS started as an illegal translation of CP/M.


Randy
 
So no CP/M has no DOS code but DOS started as an illegal translation of CP/M.

In 1979, what constituted an "illegal translation"? Really, Gary didn't have a case and he was aware of it. Reverse-engineering wasn't illegal then; there was no DMCA.

By 1979, there were other "work-alikes" of CP/M-80. Nobody got sued for that either.
 
It went to court, Microsoft was found guilty. There was a fine. There was a settlement.

The scuttlebutt is it wasn't reversed engineered, it was taken from original sources that were covered in a non-disclosure agreement.

IBM had contracted with both DRI and M$, DRI was to provide the DOS and M$ the basic.

As usual in the early computer days DRI was way behind schedule, IBM asked M$ if they could write a DOS. M$ knew 86-DOS was a stolen product but DRI hadn't brought legal action yet. So M$ said they could do it all by buying 86-DOS and selling it as Microsoft DOS.

IBM found themselves in a legal quagmire and paid the fine and agreed to sell CP/M-86.

M$ never ported their Gee-Whiz basic (GWBasic) to CP/M-86 and IBM decided to complete their legal requirements by selling CP/M-86 for four times the cost of DOS and no basic to boot.


Randy
 
What court case? Where? Could you provide a PACER reference?

IBM was a public company; any settlement would have been obvious in the filings. IBM was also still under the consent decree. Playing loose with the law was a good way to prevent the consent decree from being lifted.

Also, if there was a case that MS lost to DRI, that would have been precedent in the various reverse engineering BIOS cases and would have ensured losses for both Compaq and Phoenix Technologies.

That rather goes against all the history that exists. Strong documentation is needed.
 
The lawsuit was settled in an out of court settlement after Gary was already dead and DRI was bought my Caldera. it had been going back and forth for years. It took that long for courts to catch up with changing technology.

https://en.wikipedia.org/wiki/Digital_Research

Gary was a computer genius but not a great businessman, Bill was a genius businessman but not a computer genius.

That's why all the DRI computer languages had great math packages but M$ couldn't add one plus one and get two (literally). M$ didn't get a working math package until Visual Basic in windows 95.

As for CP/M replacements there basically were none. Several people provided BDOS replacements that required you own CP/M. The only two exceptions I can remember was IMDOS by IMSAI and TP/M by TDL.

After the PC came out some continued to replace "CP/M" but again in pieces you still had to have CP/M to have a complete package. Caldera (DRI) finally release CP/M-86 that had morphed into DRDOS to public domain (freedos).


Back "in the day" hacking a program like CP/M was considered good as long as the original got their money before the hack was put in to make it better. I hacked a program named electric pencil to run under northstar dos. Originally the electric pencil only ran on audio cassette tapes. I would sell my hack for $75 to modify a legal copy of it. Later Michael came out with a disk version and my hack was put away (and finally lost).

There is a big difference between modifying a legal program and taking it over completely.


Randy
 
After the PC came out some continued to replace "CP/M" but again in pieces you still had to have CP/M to have a complete package. Caldera (DRI) finally release CP/M-86 that had morphed into DRDOS to public domain (freedos).

Randy
Got any good references Freedos is based from DRDOS.

I know folk where enhancing DRDOS(OpenDos) well after Caldera but once Freedos had finally became a usable alternative the programmers moved over to the FreeDos project http://www.drdosprojects.de/
 
FreeDOS has _nothing_ to do with DR-DOS, Novell DOS, or OpenDOS beyond the fact that it's MS-DOS compatible.

g.
 
CPM-80 preceeded DOS by years. So you won't find DOS code in CPM, but you will find the Digital Research CPM-80 Copyright Notice and Code inside DOS 1.0 since whole sections of code were lifted from CPM-80 illegally when Seattle Computer ported CPM-80 without authorization into the 16-bit Operating System that Seattle licensed to Microsoft to sell to IBM for sale with 8088 based PCs. A friend of mine from back when I worked for Radio Shack showed me the Digital Research Copyright Notice inside of DOS 1.0 that he discovered while he was working inside of DOS. I think he was trying to find the location of the DOS serial number at the time.

This was the basis of the lawsuit that Seattle filed against Microsoft. Seattle never licensed Microsoft to sell DOS on any other platform/processor besides the IBM PC with 8088 processor. Seattle had a mysterious fire that put them out of the active retail S-100 computer selling business, but the lawsuit lingered on for years, until Microsoft finally settled with Seattle (paying them off, I think it was a token 1 million or 5 million dollars).
 
It went to court, Microsoft was found guilty. There was a fine. There was a settlement.

The scuttlebutt is it wasn't reversed engineered, it was taken from original sources that were covered in a non-disclosure agreement.

IBM had contracted with both DRI and M$, DRI was to provide the DOS and M$ the basic.

As usual in the early computer days DRI was way behind schedule, IBM asked M$ if they could write a DOS. M$ knew 86-DOS was a stolen product but DRI hadn't brought legal action yet. So M$ said they could do it all by buying 86-DOS and selling it as Microsoft DOS.

IBM found themselves in a legal quagmire and paid the fine and agreed to sell CP/M-86.

M$ never ported their Gee-Whiz basic (GWBasic) to CP/M-86 and IBM decided to complete their legal requirements by selling CP/M-86 for four times the cost of DOS and no basic to boot.


Randy



Microsoft is know for getting access to Code to this day by approaching software companies asking to see the code for software programs and applications, claiming that they are interested in licensing the intellectual property for inclusion in a future Microsoft product or revision. Microsoft signs a non-disclosure agreement in exchange for access for a specific amount of time. When the time period expires, they say "sorry we changed our minds about licensing your product" And go on their merry way. Some time later, when Microsoft unveils a new, the code from the programs or applications that they did not license after being allowed access to the Code shows up in their "new" product. Microsoft has been accused, and convicted of this strategy several times in the past. In many cases causing delay in marketing a product because the product ends up being rewritten, OR some product recalls. This is documented history.
 
CPM-80 preceeded DOS by years. So you won't find DOS code in CPM, but you will find the Digital Research CPM-80 Copyright Notice and Code inside DOS 1.0 since whole sections of code were lifted from CPM-80 illegally when Seattle Computer ported CPM-80 without authorization into the 16-bit Operating System that Seattle licensed to Microsoft to sell to IBM for sale with 8088 based PCs. A friend of mine from back when I worked for Radio Shack showed me the Digital Research Copyright Notice inside of DOS 1.0 that he discovered while he was working inside of DOS. I think he was trying to find the location of the DOS serial number at the time.

This was the basis of the lawsuit that Seattle filed against Microsoft. Seattle never licensed Microsoft to sell DOS on any other platform/processor besides the IBM PC with 8088 processor. Seattle had a mysterious fire that put them out of the active retail S-100 computer selling business, but the lawsuit lingered on for years, until Microsoft finally settled with Seattle (paying them off, I think it was a token 1 million or 5 million dollars).

Gotta call "shenanigans" on this one, sorry.

You can find 86-DOS 1.0 here There is no mention of Digital Research in it. I've grepped the binaries for every pattern that might match and can't find a single instance. The same for my copy of PCDOS 1.1 and MS-DOS 1.26.

Further, "reverse engineering" in 1980, as long as it did not plagiarize code directly or rely on trade secrets was completely legitimate in 1980. There was a whole pile of lawsuits during the 1980s as to what constituted software plagiarism, so there's plenty of case law on this. This was all before DMCA.
 
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FreeDOS has _nothing_ to do with DR-DOS, Novell DOS, or OpenDOS beyond the fact that it's MS-DOS compatible.

...except for DR-DOS 8.1, which got caught copying some of FreeDOS's utilities without giving it credit as required by the GPL, and was subsequently withdrawn.

http://www.freedos.org/technotes/press/2005-drdos.txt

And DR-DOS has always displayed a copyright dating back to 1976, implying that it contains some CP/M code.

DR-DOS-8.PNG
 
And, as I posted on cctalk, reverse-engineering CP/M 80 is no great feat--I've done it without resorting to disassembly or proprietary documentation. Heck, it's less than 16KB of code all told. Not even as difficult as reverse-engineering a PC BIOS.
 
Gotta call "shenanigans" on this one, sorry.

You can find 86-DOS 1.0 here There is no mention of Digital Research in it. I've grepped the binaries for every pattern that might match and can't find a single instance. The same for my copy of PCDOS 1.1 and MS-DOS 1.26.

Further, "reverse engineering" in 1980, as long as it did not plagiarize code directly or rely on trade secrets was completely legitimate in 1980. There was a whole pile of lawsuits during the 1980s as to what constituted software plagiarism, so there's plenty of case law on this. This was all before DMCA.



It's been over 30 years since I witnessed the display of the Digital Research Copyright Notice inside of DOS 1.0. But it was there. The Demonstration was repeatable at the time, I wrote the steps down and did it myself at home after I was shown how it was done. While I can't demonstrate the Digital Research Copyright Notices in PC DOS 1.0 any longer, I can show a copy of the Digital Research GUI/Windows type OS that was shown to me before Microsoft introduced Windows to the world back in around 1980. Microsoft did not invent GUIs and Windows, despite what they claim. Xerox SPARC created/invented/developed GUIs as used by Microsoft in Windows, and Digital Research had a working GUI in 1980 that they could have marketed (and should have had the right to copyright before Microsoft, if you think Microsoft had the right). It was demonstrated to me on a Compupro running a 68K processor back around 1980. I still have copies on 8" floppy disks.

I've never used the Seattle 16-bit OS, nor seen anyone try to display the Digital Research Copyright Notice/s in a copy of Seattle's 16-bit (like was shown to me in PC DOS 1.0).

I believe that Seattle Computer eventually settled with Digital Research, just as Microsoft eventually settled with Seattle Computer. The litigation went on for years past the demise of Gary, and Seattle Computer.

The code used by Seattle Computer that came from CPM-80 was a direct copy going into Seattle's 16-bit OS. In later years the Principles from Seattle admitted that they simply ported CPM-80 to a 16-bit platform. It was done word for word, and contained mistakes carried from CPM-80.

Have you tried looking in a copy of PC DOS 1.0 (which is where I was shown the Digital Research Copyright Notice). IBM worked rapidly to redo PC DOS after releasing it, and did eventually eliminate the Digital Research Copyright Notice/s from PC DOS. Why do you think you have version 1.1?
 
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