TOPS-20 MDL FLOAD Error

[David Meyer]

Playing with the old Lisp-like language MDL (actually MDL105) on TOPS-20 on an simulated PDP-10, I get the following error whenever I try to load source code from a file with <FLOAD "file-name">:

?:$ FATAL ERROR FIXUP FILE NOT FOUND $

The result is the same if I specify file-name as "FILE", "FILE.MUD", or "<DIRECTORY>FILE.MUD".

I encountered a similar error playing with Maclisp on the same system recently, and in that case it was a matter of needing a particular logical name to point to a particular directory where Maclisp modules were stored, but I don't seen anything that looks like a collection of MDL modules on the system, and I've been unable to find anything helpful in MDL documentation.

Any guesses? Any of the Zork Fathers lurking here?

[Rich Alderson]

David Meyer <papa...@gmail.com> writes:

> Playing with the old Lisp-like language MDL (actually MDL105) on TOPS-20 on=
> an simulated PDP-10, I get the following error whenever I try to load sour=

> ce code from a file with <FLOAD "file-name">:
>
> ?:$ FATAL ERROR FIXUP FILE NOT FOUND $
>

> The result is the same if I specify file-name as "FILE", "FILE.MUD", or "<D=
> IRECTORY>FILE.MUD".
>
> I encountered a similar error playing with Maclisp on the same system recen=
> tly, and in that case it was a matter of needing a particular logical name =
> to point to a particular directory where Maclisp modules were stored, but I=
> don't seen anything that looks like a collection of MDL modules on the sys=

> tem, and I've been unable to find anything helpful in MDL documentation.
>
> Any guesses? Any of the Zork Fathers lurking here?

If I remember correctly, the logical name in question is MDL:, and you might as
well point it at DSK: (the connected directory) or at SYS: (which is probably
not as good a target).

CStacy, you reading this?

--
Rich Alderson ne...@alderson.users.panix.com
Audendum est, et veritas investiganda; quam etiamsi non assequamur,
omnino tamen proprius, quam nunc sumus, ad eam perveniemus.
--Galen

[David Meyer]

Thanks, Rich, but defining MDL: as DSK:, SYS:, or <GAMES> (where MDL105.EXE is stored) makes no difference.

[David Meyer]

On Friday, September 9, 2016 at 1:18:43 PM UTC+9, David Meyer wrote:
> Thanks, Rich, but defining MDL: as DSK:, SYS:, or <GAMES> (where MDL105.EXE is stored) makes no difference.

Taking a look at MDL again on the new Toad-2 reincarnation of twenex.org, I encountered the same problem. I came back to this thread and thought some more about Rich's advice, and hit on the solution:

EITHER specify the full file specification DEV:<DIR>NAME.TYP of the MDL source to FLOAD (no need to define MDL:; .TYP can be omitted if ".MUD").

OR define logical name MDL: to point to the source file DEV:<DIR>. If FILE.MUD is in my login directory, then on twenex.org I have to set MDL: to PUBLIC:<PAPA>. Then <FLOAD "FILE"> works as advertised.