From: linstee@dutecaj.et.tudelft.nl (Erik van Linstee)
Subject: Re: Windows 3.1 an "operating system"?
Organization: Delft University of Technology, Dept. of Electrical Engineering
Date: Sun, 08 Nov 1992 10:50:45 GMT

discar@nosc.mil (Joe Discar) writes:

>In article <1992Nov06.215249.9731@donau.et.tudelft.nl> linstee@dutecaj.et.tudelft.nl (Erik van Linstee) writes:
>>discar@nosc.mil (Joe Discar) writes:
>>
>>>In article <1992Nov5.225251.14539@mksol.dseg.ti.com> mccall@mksol.dseg.ti.com (fred j mccall 575-3539) writes:
>>>>In <7734@lib.tmc.edu> jmaynard@oac.hsc.uth.tmc.edu (Jay Maynard) writes:
>>>>
>>>>>In article <1992Nov5.165623.808@mksol.dseg.ti.com> mccall@mksol.dseg.ti.com (fred j mccall 575-3539) writes:
>>>>>>In <7714@lib.tmc.edu> jmaynard@oac.hsc.uth.tmc.edu (Jay Maynard) writes:
>>>>>>>A neat analogy, Fred, but wrong: what does an OS do that DOS doesn't?
>>>>>>Gee, Jay, tell me what definition of 'OS' you're using.  :-)
>>>>
>>>>>A suite of programs that insulates application code from the necessities of
>>>>>dealing directly with the hardware.
>>>>
>>>>And a reasonable definition it is, too.  Ok.  DOS fails the test
>>>>because:
>>>>
>>>>1) Anything doing graphics pretty much has to go straight to hardware,
>>>>the 'insulation' that DOS provides being so worthless.
>>>>
>>
>>>Fred, DOS provides (via the BIOS) functions to switch to graphics modes nad
>>>plot pixels on the screen.   The routines are slow and don't work
>>
>>The BIOS is NOT part of DOS so the rest of your argument is of no
>>consequence. In fact, isnt the VGA bios on the device itself?!

>Regardless, several texts, DOS Power Tools by Paul Somerson (Bantam Books),
>MS-DOS Developer's Guide (Howard Sams & Company) all regard the INT 10
>routines as valid "DOS" ways of accessing the video card.

Yes, because the BIOS is part of the architecture DOS was designed for.


>Being able to use the BIOS to perform a task does not invalidate the
>operating system's compliance with an "OS definition."  If this were true,
>OS/2 2.0 (indeed *any* PC based operating system) would not be an
>"operating system."

Never said, nor anyone else I think, anything of the sort.


>Why?  Because *all* of them use the BIOS--if only just to boot from the
>hard disk.  This is *part* of the PC-architecture.

Noted.

>>
>>>(naturally) with graphics modes that came out AFTER DOS's/BIOS design.
>>>But from a realistic standpoint, it can't been expected that ALL hardware
>>>will be supported by an OS.  Take for example my Lantastic network card--
>>>it doesn't work under OS/2 under any circumstances (even if I try to use
>>>a generic NE2000 driver).  Does this mean OS/2 is not an operating 
>>>system?  No... of course not, it means my network card is not
>>>quite a standard.
>>
>>Remember the OS is not required to manage every piece of harware,
>>but if a piece of hardware is to be managed, it is to by done
>>by the OS.
>>
>Fildercarb.  The BIOS is *part* of DOS... as much as a V6 is *part* of the
>Truck my father drives.  It is not necessary that every layer in an

No its not.
1. You can remove DOS and there's still the BIOS, or take out the VGA
card and the BIOS is gone. Not a very good argument, but it shows the
BIOS and DOS are unrelated, DOS just makes use of its presence, as
it does of any piece of the architecture it was designed for.

2. The BIOS is not designed by Microsoft for DOS, but DOS was designed
for the PC-architecture, using the BIOS. Argument in same class as 1.

3. Any other PC operating system uses the BIOS for basic input and
output. The BIOS would then be part of that operating system,
by your own reasoning. That would make all these OS's have an 
identical part. Not likely. More likely though is, the BIOS is
part of the architecture the OS is designed for.

4. You yourself just said the BIOS was part of the architecture.

>operating system is "blind" to only the layer directly below it (in modern
>times, such abstraction is good design--but it is far from necessary).
>Are you saying that, for example, if you as a programmer needed to write
>a character to the screen, you should write your own video driver?  Of
>course not.

Of course not, I would have to use the OS service if I was writing
an application, and I would have to use the architecture of the
machine I am designing for if I was designing an OS. In the latter
case the logical thing to do would be to use the BIOS, since
that is the part of the architecture that is guaranteed to be
compatible from machine to machine.


>>
>>>>2) Accessing upper memory.  DOS is so braindead that it requires
>>>>'extenders' to get outside 640k.  So much for 'insulation' on
>>>>management of the majority of memory on the machine.
>>>>
>>
>>>So, there is no requirement for an OS to be able to access ALL of memory
>>>(various operating systems running in a VM can't).  
>>
>>>Again, if you could find such a requirement, cite a bibliographical
>>>reference and I'll get off your back.
>>
>>>>Shall I continue?  ;-)
>>>>
>>>>-- 
>>>>"Insisting on perfect safety is for people who don't have the balls to live
>>>> in the real world."   -- Mary Shafer, NASA Ames Dryden
>>>>------------------------------------------------------------------------------
>>>>Fred.McCall@dseg.ti.com - I don't speak for others and they don't speak for me.
>>-- 
>>Erik van Linstee   |   Delft University of Technology   |   I'll be back ... 
>>----
>>   We are god, 'cause only we can create the idea of his existence
>>   in our holy brains...  (Yello)


-- 
Erik van Linstee   |   Delft University of Technology   |   I'll be back ... 
----
   We are god, 'cause only we can create the idea of his existence
   in our holy brains...  (Yello)