7 Apr
2000
7 Apr
'00
3:16 p.m.
I know what he means, Allison. Unlike those who earn their money writing
code for the OS's we use, I see writing code as overhead most of the time.
I've written a few hundred K-lines of mostly assembler, but am taking the
position of a user, with which position I can easily identify, and as such
don't see the similarities in the two OS' because I'm using an application
which handles the interface to the OS for me and lets me focus on useful
work.
I'm not saying programming isn't useful work, but rather that most people
not directly engaged in generating software consider it overhead or "not my
job" and therefore uninteresting. The secretary using the word processor
isn't interested in or aware of the how's of opening a file. He/she just
wants it done. One who sees from that perspective sees the glaring
differences between CP/M and MS-DOS, yet doesn't see the similarities to
which reference has been made, whether they're real or not.
Since MUCH fewer than 1% of the people who use MS products are engagedin
activity which would make them aware of the differences and similarities
between MS-DOS and CP/M if they knew both OS' I'd have to say the internals
are really never going to be part of a legal argument. Most judges, after
all, don't write their own programs.
Dick
----- Original Message -----
From: allisonp <allisonp(a)world.std.com>
To: <classiccmp(a)classiccmp.org>
Sent: Friday, April 07, 2000 7:04 PM
Subject: Re: !Re: Nuke Redmond!
Of
all
It's like saying a FORD is a copy of a
Dusenberg because they both use
wheels.
This was a feature unique to CPM and DOS as many others loc(0) was
either reset (hard), ROM, unused or reserved.
help.
Visicalc!
>> the same, with a few notable exceptions where
the concept don't match
>> (MS-DOS for example does not have an IOBYTE).
>
>What of those things internal would you have had them leave out in order
to
>be more different from CP/M, which was a VERY
popular OS at the time,
>without removing its functionality. Since the features to which you
refer
>are internal, I assume you have precice citations
of common source code,
>right? They're certainly not obvious to me in my role as a fairly
frequent
user.
The features he refers to are the calls to the BDOS to do things like
File_OPEN,
FILE_CLOSE, FILE DELETE..... and so on.
>Since there is only one segment in CP/M, I guess you've got 'em there.
>course it really doesn't matter what the
location is, does it? I guess
any
OS that load a
register and then calls a specific location is a copy of
CP/M, right?
Not really, CPM loaded to a specific segment but apps could use any and to the then 8086 1mb limit.
>> You can also terminate a program by calling location 0000h (again, in
a
>> COM program). In CP/M this causes a warm
reset (similar
functionality).
The mapping of one register set into the other is
not an accident. Ask
Intel about that! I'm told that CP/M-86 is considerably more than a
translation of CP/M-80. Now you suggest that the roots of MS-DOS are
entirely in CP/M? They may have common roots, as they reflect the then
CPM-86 was not entirely 8080 code lofted, that would never ru without Also there was a loader change implemented, boot loads
a file system aware
loader that finds cpm.sys. This was not the 8080 way.
As far as register usage, that is an artifact of PLM used to write the
V1.3/1.4
and later versions of CPM80. With that convention established it was kept
to keep applications that called the BDOS compatable.
wants
I've heard that, too. Does that mean that
anyone who writes a program to
do
what he's seen another program do is making a
copy? You're not even sure
he
>actually saw and read the source code. How many programmers do you know
>who'd simply copy someone else's work in a case like this? Everybody
to leave his
own mark.
DOS 1.0 had COPYRIGHT Digital Research INC inside! There was a quiet
copyright battle that forced DOS 2.0 (buggiest thing in the world!). This
is not
fiction and it was documented.
Buying something that shortens your burden is
kind-of like buying an
integrated circuit rather than making the thing yourself starting with a
wheelbarrow of sand. The fact that Microsoft knew that IBM had gone to
Kildall probably told them what they wanted was sort-f like CP/M.
They didn't care only that there would be apps for it to run like
Allison