MS-DOS 2.0 and "semi compatibles" - test-drb@ccmp.vtda.org

23 Feb 2006

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  -----Original Message-----
 From: Chuck Guzis [mailto:cclist at sydex.com]
 Sent: Thursday, February 23, 2006 8:23 PM
 On 2/23/2006 at 7:05 PM Kelly Leavitt wrote:

 I just imaged a disk of an MS-DOS compatible
computer (Tandy   2000). Does
 anyone here know the magic number of an exe under
ms-dos 2.0? I had  assumed
 that it was MZ, like current exe files, but I only
see 2 or   3 occurrences
 of this in the entire data stream from the disk.
On the plus   side, I see
 LOTS
 of strings that tell me I have actually read the
contents of the disk  (this
 machine used DS/QD drives).  
 Why does this surprise you?  I think that it'd be safe to say that the
 preponderance of executables in the old 2.0 and before days were .COM
 files.  But AFAIK, it's always been MZ--though I can check my 
 DOS 2.0 and
 DOS 1.1 docs for you. 
Well, there are 8 or 10 programs on the disk in question. Shouldn't MZ then
show up 8 or 10 times. If I find a good hex editor I can read the DIR
structure and figure out where the files start and see what is there.