REXX is an interesting programming language. If you need a nice glue
language for your cmdline use, a macro language for internal app use,
or just something simple to hack around with, it's the perfect candidate.
And it's portable, ANSI standard [1996], and (in this implementation)
free/libre!

  http://en.wikipedia.org/wiki/Rexx
  http://www.kilowattsoftware.com/tutorial/rexx/
  http://www.rexxla.org/
  http://www.rexxinfo.org/
  http://regina-rexx.sf.net/

Like most REXX implementations, Regina is an interpreter. In particular,
my two "unofficial" Regina REXX .ZIP archives (386+, LGPL) here may be
of some interest to DOS fanatics:

REX35DLL.ZIP

  This is basically a kludgy attempt at getting .DLLs (actually, ELF .so)
  working on DOS via the third-party DJELF package (see any DJGPP mirror).
  I didn't test it with any real .DLLs (e.g. Regutil), but it works with
  the simple examples, at least. Note that to recompile you will need the
  original GCC400B.ZIP (et al.) from DJGPP as well as the DJELF binary
  replacements (and GNU Make).
  
  http://www.delorie.com/djgpp/getting.html
  
  http://na.mirror.garr.it/mirrors/djgpp/beta/v2/djdev204.zip
  http://na.mirror.garr.it/mirrors/djgpp/deleted/v2gnu/bnu216b.zip
  http://na.mirror.garr.it/mirrors/djgpp/deleted/v2gnu/gcc400b.zip
  http://na.mirror.garr.it/mirrors/djgpp/beta/v2gnu/mak381b.zip

  http://na.mirror.garr.it/mirrors/djgpp/djelf/gcc400e.zip
  http://na.mirror.garr.it/mirrors/djgpp/djelf/djdev2e4.zip
  http://na.mirror.garr.it/mirrors/djgpp/djelf/bnu216e.zip

REX36DJG.ZIP
  This is the usual boring (old) way to compile Regina with DJGPP.
  No dynamic loading is permitted, but it's a full package with everything.
  Note that unlike above, external queues are NOT disabled here (but
  keep in mind that wasn't for technical reasons, only simplicity,
  you could probably rebuild it, but for now, I left it as-is, esp. since
  the layout of his makefiles for shared lib support was unknown to me
  and I didn't know a "clean" way to get it built under DOS).
  
  But it requires built-in Watt-32 (and hence TCP/IP via packet driver)
  for that particular feature to work, supposedly. I have not tested that,
  but I tried to closely mirror the last 3.5 build .ZIP package of Mark H.
  
  N.B. Actually, 3.6 doesn't have a DOS build yet as Mark H. is quite busy,
  but he insists that 3.7 will have some improvements. Thanks, Mark!

Here's some other stuff you may want / need (Watt-32 srcs, packet driver,
DPMI host):

  http://home.broadpark.no/~gvanem/
  
  http://www.crynwr.com/drivers/
  http://www.georgpotthast.de/sioux/packet.htm
  http://www.brutman.com/Dos_Networking/
  http://www.rubbermallet.org/software.html
  http://www.glennmcc.org/
  http://dillo-win32.sourceforge.net/DOS/
  http://code.google.com/p/nanox-microwindows-nxlib-fltk-for-dos/downloads/list
  http://www.softsystem.co.uk/products/swsvpkt.htm
  
  http://homer.rice.edu/~sandmann/cwsdpmi/index.html
  http://www.japheth.de/HX.html
  
Heck, here's the latest FreeDOS 1.1 (install CD only, no LiveCD) with sources:

  http://www.ibiblio.org/pub/micro/pc-stuff/freedos/files/distributions/1.1/

So that should be enough to get you started. If you need additional help,
you can try one of the following communities (or similar) online:

  http://groups.google.com/group/comp.lang.rexx/topics
  http://groups.google.com/group/comp.os.msdos.djgpp/topics
  http://www.bttr-software.de/forum/board.php
  http://sourceforge.net/mailarchive/forum.php?forum_name=freedos-devel

rugxulo _AT_ gmail _DOT_ com
http://sites.google.com/site/rugxulo/
16 Feb 2012