Most of this "stuff" builds and runs under DOS

    I  mostly used: Microsoft DOS 5
    I've also used: Windows 9x/2000/XP/7/8 (but only 32 bit versions)
      - I've never seen any of these available "free".

    At one point, IBM gave away PCDOS which is very compatible/almost the same
      - Officially available in: free "IBM ServerGuide Scripting Toolkit"
    FreeDOS, CalderaOpenDOS and PtsDOS should also work
      - All are/were free - I've not used/tested them much.
    - Boot images for all of these are included within my "DBBD"

  My RealDOS setup:
    C: main drive
        \DOS    main DOS install
        \CMDS   additional commands/utilities I added
        \MC     Micro-C
        \TC     Borland Turbo-C (only needed for a bit of my stuff)
    R: RamDisk - I use for/because:
        Nice/fast place for temp files - auto cleared on shutdown.
        Compilers tend to uses "".
    D: RamDisk in my earlier systems
        You can: SUBST D: R:\
    AutoExec:
        PATH C:\Cmds;C:\MC;C:\TC;C:\DOS
        set TEMP=R:\
        set MCDIR=C:\MC
        set MCTMP=R:\$

For other systems (including 64bit Windows) - I use DosBox which is a very
good DOS emulator - I recommend the one I've posted on my site:

  My DosBox setup:
    Z:  internal DosBox - commands etc.
    Y:  DosBox home direcrory - I use C:\DosBox - mount Y C:\DosBox
        \CMDS   additional commands/utilities I added
        \C      where I put C:
    C:  Main working drive - I store in "" - use: SUBST C: Y:\C
        \MC     Micro-C
        \TC     Borland Turbo-C (only needed for a bit of my stuff)
    R:  RamDisk - I create on host as R: - mount R R:\      
    AutoExec:
        PATH Y:\Cmds;C:\MC;C:\TC;Z:\
        set TEMP=R:\
        set MCDIR=C:\MC
        set MCTMP=R:\$

I you don't have/want a RamDisk, use C:\R
    DOS/WIN - SUBST R C:\R
    DosBox  - mount R C:\R

Tools you can use (To build the way I did):
    DDS Micro-C/PC compiler (available on my site)
    DOS/8086 assembler and linker:
        I originally used MASM and LINK but changed to Borland TASM/TLINK
        as it handled larger files. I've never seen MASM/LINK available free,
        but "Borland Comunity Museum" had TASM/TLINK as a free download.
            You can get TASM.ZIP from my site
    Borland Turbo-C 2.0
        I've never seen this "officially" free, but I have seen it available
        in various places on the web.
    DDS XASM various embedded assemblers (available on my site)
    LccWin32 - free - copy I used (3.8) on my site

To compile most things with Micro-C/PC:
    cc name -[P]OF[M] [M=S]
        -Preprocess
          Uses the full Micro-C preprocessor. Some of my early "stuff" used
          only the limited preprocessor built into MCC.EXE - look for:
            #include <file> | #include "file"       -P IS needed
            #include file (no <> "")                -P NOT needed
        -Optimize           Invokes MC's peephole optimizer
        -Foldliteral
          C "standard" says all string literals are stored uniquely:
            "ThisString"
            "String"
          Without -F, MC generates:
                MOV AX,OFFSET DGRP:?0+0
                MOV AX,OFFSET DGRP:?0+11
?0 DB 84,104,105,115,83,116,114,105,110,103,0,83,116,114,105,110,103,0
          -F causes MC to combine the strings:
                MOV AX,OFFSET DGRP:?0+0
                MOV AX,OFFSET DGRP:?0+4
?0 DB 84,104,105,115,83,116,114,105,110,103,0
        M=S                 build SMALL model (otherwise TINY)
          Most of my "stuff" happily fits in (64k code+data) 8086 Tiny .COM
          model but some need Small .EXE model (64k code + 64k data)
        -Module
          Does not LINK - builds name.OBJ
          When multiple source files to one executable:
            cc name1 -pofm      buikd name1.OBJ
            cc name2 -pofm      buikd name2.OBJ
            lc name1 name2      combine into name1.COM


Some of my stuff uses extra "help" files. To create these, use my:
  HFC - Help File Compiler
    Reads the provided .SRC help source file, and produces a .HLP hypertext
    linked file for interactive help within the program.
  CHT - C Help Text
    Reads "comments" in a .C source file to create a Help.H file containing
    character arrays of help text in a form which saves some space and can be
    "#include"d in the .C


You can build much of my DOS stuff for Windows/Linux with DVM
(DunfieldVirtialMachine): DVM cc program