DEBUG.COM 2.10-je1 build directory               John Elliott, 31 October 2018
==============================================================================

This is an attempt to adapt the MIT-licenced MSDOS 2.11 source release at 
<https://github.com/Microsoft/MS-DOS/> to build, the 2.10 DEBUG.COM also 
present in that release. Since DEBUG.COM was in the MIT-licensed release, 
I reasoned that it was permissible to disassemble it and create matching 
source code.

This does not build to a byte-for-byte replica of the original, because of
a couple of changes - I uncommented the code that displays the version 
number, and added a bug fix for the long-standing[*] bug that points CALL 5 
at the wrong address in the PSP created by DEBUG.

[*] Seriously, it's in every release of DEBUG from MS-DOS 2 to Windows 10. 
It's enough to make one think Microsoft are deliberately replicating it in
each new version.

Build requirements:
* MASM 4.00 (MASM 3.00 may also work)
* LINK (I used Microsoft LINK 2.40).
* EXE2BIN (I used EXE2BIN 1.00 from DRDOS 6)

Build scripts:
* MK.BAT    builds DEBUG.COM
* CLEAN.BAT removes intermediate build files
* ZIPIT.BAT builds the zip file containing everything

Changes I have made to convert the 2.11 source to 2.00 are mostly flagged 
[JCE], for ease of examination; though I haven't commented on the movement
of functions from one module to another.