What's causing this (problem found in a few Forth for DOS implementations)?

[Zbig]

I found two Forths - old implementations for DOS - which don't work properly; I mean in particular two of the ones listed at Simtel:

eforth.zip 49630 900728 Ting's PD portable eForth, ROMable, w/asm src
fig86.zip 38189 821119 Original Fig-86 Forth compiler

( http://esca.atomki.hu/simtel/msdos/forth.html )

The issue is: after any of these has been run it recognizes only most basic words, like . (dot), + - etc. A quick peek into binary allows to see other words' names. I tried to assemble eForth from included ASM source - no difference. New executable is flawed the same way.

Maybe someone stumbled upon this in the past and knows the origin of the problem? I tried it on my Athlon XP under FreeDOS. I believe DOS compatibility doesn't that matter in this particular case (FreeDOS is very compatible anyway), probably something very closely 8088/8086-related and expected by both Forths hasn't been found?
It would be good to learn what's causing this to avoid such issues.

[peter....@gmail.com]

Have you tried Caps Lock. They might be case sensitive and only recognize uppercase

Peter

[Zbig]

> Have you tried Caps Lock. They might be case sensitive and only recognize uppercase

OMG :)))))

Indeed... thanks, I was looking for something "very unusual". ;)

[Helmar Wodtke]

Hehe nice, that you figured out something for DOS-Forths ;) Take a look at the txfwia version for a DOS-Forth (might be most recent one Forth made for DOS). https://bitbucket.org/helmwo/txfwia/src/default/non-ans/msdos/
There you find also a debugger that is Forth-based and is really advanced for its time ;)

Regards,
-Helmar

[Zbig]

> Hehe nice, that you figured out something for DOS-Forths ;) Take a look at the txfwia version for a DOS-Forth (might be most recent one Forth made for DOS). https://bitbucket.org/helmwo/txfwia/src/default/non-ans/msdos/
> There you find also a debugger that is Forth-based and is really advanced for its time ;)

I'm not sure is it intended, but after first "quick glance" I noticed following:

- no stack tracing; it allows "pulling" from stack with no restriction
- probably no check for "compiling only words"; I typed "4 0 do i . loop" directly in console - to find out, whether it allows this like OF does - but it did, well, strange things ;)
- it's not greeting me with usual "OK" (and without "OK" on any error). Would I have "OK" I could be more sure that's everything is, well, OK. ;)

Maybe all this for the sake of simplicity?

If you could attach some kind of more detailed docs describing your design decisions, details of implementation, initialization procedure, of course things like memory map etc. it can be interesting learning tool.

[Helmar Wodtke]

Yes, that is for simplicity. It's not a learning tool for now. It works from an "early crash"-philosophy. It means you can shoot the foot ;)
That missing of "OK" is common to most of my Forths. Did you also try the debugger (DEBSCR.COM)? Contrary to notice, I do have sources for it. That Forth it uses is just more "weird" in my opinion, but is one of the first that survived in source from me from this time...

Regards,
-Helmar

[Helmar Wodtke]

A hint: for DEBSCR.COM use dosbox, not dosemu. Unfortunately dosemu does not emulate that well. On a real machine it works best...

Regards,
-Helmar

[Zbig]

> Yes, that is for simplicity. It's not a learning tool for now. It works from an "early crash"-philosophy. It means you can shoot the foot ;)
> That missing of "OK" is common to most of my Forths. Did you also try the debugger (DEBSCR.COM)? Contrary to notice, I do have sources for it.

Looks interesting indeed - I believe ForthDOS maintainers/developers could be eager to include it into their software tree. I'll examine it further - looks for more friendly than standard DOS' "debug".

[Zbig]

> A hint: for DEBSCR.COM use dosbox, not dosemu. Unfortunately dosemu does not emulate that well. On a real machine it works best...

I meant FreeDOS, of course - not ForthDOS. :) Yes, I'm testing it on real machine.

One thing worthy to add: some help screen shown when parameter "-h" (and more DOSsy "/?" as well) is used. And that screensaver feature isn't that useful in the era of LCD monitors; it could be optional with default "off".

[Helmar Wodtke]

Yeah ;) It comes from time of big monitors... I used it for analysis of some software. It has some special features to recover DOS from installing TSR under the debugger. It keeps track of some important lists in memory. That screen saver feature was needed at the time.

Regards,
-Helmar