16 ms·

The DUNGEON (Zork I) source

94 points by geospeck 9y ago

homarp 9y ago
In http://blog.zarfhome.com/2017/08/your-load-is-too-heavy-zork-deep-reading.html http://blog.zarfhome.com/2017/08/your-load-is-too-heavy-zork... , Andrew Plotkin was pointing to an Inform 6 version of Zork by Allen Garvin , http://plover.net/~agarvin/zork1.txt http://plover.net/~agarvin/zork1.txt derived from the original decompiled Z-machine code.
- homarp 9y ago
  And http://plover.net/~agarvin/zorkbugs.txt http://plover.net/~agarvin/zorkbugs.txt is a list of Zork bugs.
JoeDaDude 9y ago
This was also discussed a couple of days ago: https://news.ycombinator.com/item?id=15138114 https://news.ycombinator.com/item?id=15138114
larrykwg 9y ago
reading old C like this, I always wonder how could people code like this back then but apparently it was transpiled from fortran. So I'd assume the original code looked better. I dug around and found it, for comparison here is the original rooms.f vs. rooms.c: https://paste.ubuntu.com/25458063/ https://paste.ubuntu.com/25458063/ https://github.com/mgius/zork/blob/master/rooms.c https://github.com/mgius/zork/blob/master/rooms.c Here is the full fortran code: http://gunkies.org/wiki/Zork#Source_code http://gunkies.org/wiki/Zork#Source_code
- ajross 9y ago
  Pretty sure the fortran was itself a port. My apocryphal memory is that the original is for some custom system, which wikipedia tells me was "MDL". The fortran was the result of it being carried to more common systems.
  - ghaff 9y ago
    Yes. The Infocom games were written in MDL, which was a LISP derivative.
    - digi_owl 9y ago
      And developed on a PDP-11 almost too the end of the company...
      - abecedarius 9y ago
        Weren't they using a 10? I don't remember but it'd at least be surprising not to while they were still at MIT.
        digi_owl 9y ago
        Ah yes, my bad. And it is not even that long since i read the history on Filfre. Guess i have been reading so much about the 11 i got the two mixed...
        abecedarius 9y ago
        The 11 had such a pretty instruction set, though it was kinda small for developing a program like Zork.
        ghaff 9y ago
        I think they eventually had a TOPS-20.
- jghn 9y ago
  One of the gnarliest code bases I ever worked in was a very large C project where the inner core had been run through a f2c transpiler. Over the subsequent decade the surrounding code was a hodgepodge of people taking their own interpretations of autogenerated C code because folks didn't question why the code looked the way it did and thus they did their best to maintain the same look and feel. Oh and no one really knew how that original inner core worked, there were no docs, no oral tradition, and it was over 20 years old. While I was still working there we accumulated enough major change requests to the application that finally got the go ahead to throw the original code base out and start from scratch.
- emddudley 9y ago
  The download links at http://gunkies.org/wiki/Zork#Source_code http://gunkies.org/wiki/Zork#Source_code are all broken.
  - larrykwg 9y ago
    atleast this one worked: http://simh.trailing-edge.com/games/dungeon.zip http://simh.trailing-edge.com/games/dungeon.zip (Bob's port to Fortran)
- DonHopkins 9y ago
  The original MDL source code is beautiful to read: https://github.com/itafroma/zork-mdl https://github.com/itafroma/zork-mdl
  - larrykwg 9y ago
    thanks I hope thats the end of that rabbithole, that MDL almost looks like XML neat: https://github.com/itafroma/zork-mdl/blob/master/rooms.mud#L827 https://github.com/itafroma/zork-mdl/blob/master/rooms.mud#L...
    - gedy 9y ago
      Would be interesting to make a React port of this for the web, might look similar to MDL
    - chc 9y ago
      It looks exactly like Lisp to me, just with angle brackets rather than parens.
      - jcelerier 9y ago
        That's because both LISP, XML (and React) are just trees.
  - pkaye 9y ago
    Honest question as someone who never got comfortable with Lisp languages. Is the code in parser.mud easy to read. One of those 100 line functions, could you jump to the middle of it and start understanding the meaning as someone familiar with C like languages? Even though I can figure out the syntax it looks like line noise to me but perhaps it is because i've not done much Lisp coding.
    - jsnell 9y ago
      I wouldn't call that code easy to read, and that's coming as someone who has actually at some point learned enough MDL to actually know the syntax rather than have to reverse engineer it on the spot. There's a couple of reasons why that code is rough to read today: - It's doing very complicated operations that operate on mutable global data, and structuring it as huge and deeply nested functions rather than splitting the operations up to smaller chunks with meaningful names. But you'd see exactly the same kind of thing in non-Lisp source code of that era; it's just different sensibilities. - The code is incredibly heavy on conditionals. Which makes sense given the problem domain: parsing a pseudo-natural language. But MDL is a language where the conditionals kind of suck. COND is basically unreadable in any Lisp, you'd very rarely see people use it today. In CL you'd have more readable options like IF, WHEN and UNLESS. In MDL the only option is misusing short-circuiting AND/OR as a poor man's IF. Which they do in places, which doesn't help readability either. - The use of angle brackets makes everything look like a sea of less-/greater -than comparisons. At least I just can't help it. It's especially bad when combined with the array indexing syntax.
- michaelcampbell 9y ago
  What version of c used integer and logical as type decls?
scelerat 9y ago
A cavalcade of GOTOs
- contingencies 9y ago
  Back then, stacks (and the private namespaces resulting from the use of functions/methods in most modern languages) were probably considered a superfluous resource indulgence: 1970s bloatware.
- smegel 9y ago
  Might have been ported from assembly, this is not really the very original source. As someone said, version one was for mainframe or something.
  - Narishma 9y ago
    It was ported from Fortran, and that version itself was ported from the original written in a LISP derivative called MDL.
rhspeer 9y ago
It would be interesting to refactor zork into HTML+CSS and set it up like cssZenGarden.com so folks could add their own designs. Although a much smaller text adventure game would me more achievable.
- lgas 9y ago
  You can create HTML based interactive fiction with the latest inform: http://inform7.com/ http://inform7.com/
- throwanem 9y ago
  That's basically Twine: https://twinery.org https://twinery.org
  - rhspeer 9y ago
    that's new to me, thanks!
SoMisanthrope 9y ago
The Zork Anthology is available for $6 on Steam.... just saying :-) I'm reliving my childhood. Used to play it on a TRS Model III. Good times!
teddyh 9y ago
See also Open Adventure: https://gitlab.com/esr/open-adventure https://gitlab.com/esr/open-adventure “This code is a forward-port of the Crowther/Woods Adventure 2.5 from 1995, last version in the main line of Colossal Cave Adventure development written by the original authors. The authors have given permission and encouragement for this release, it obsolesces all the 350-point versions and previous 2.x (430-point) ports.”
- taeric 9y ago
  Knuth has a version of this game. Fun read: http://www-cs-faculty.stanford.edu/~knuth/programs/advent.w.gz http://www-cs-faculty.stanford.edu/~knuth/programs/advent.w....
  - svat 9y ago
    Note: Best to run that program through `cweave` and read the typeset output, rather than read the `.w` file directly.
    - taeric 9y ago
      Indeed, I should have mentioned this. Thanks! This is also a chapter in https://smile.amazon.com/Selected-Papers-Games-Lecture-Notes/dp/157586584X/ https://smile.amazon.com/Selected-Papers-Games-Lecture-Notes... I would be lying if I said this was super easy to read. It is easy, though. Not sure if it is a good exposition for literate programming. I certainly like it, but I think I was predisposed to.
      - svat 9y ago
        Yeah when reading some of Knuth's literate programs, I get the feeling that they are probably the best possible exposition of programs that are not so good to read. :-) That is, the programs aren't structured modularly like good modern programmers would write (encapsulation, separation of concerns, etc.) — instead they freely use global variables, gotos, etc., in the programming style of the 60s with some of Knuth's idiosyncratic improvements. But given that "bad" program, the one with the globals and the gotos, Knuth's literate programming system produces what is probably the best possible exposition of that program — at least for reading as printed material (on paper not on screen).
crocal 9y ago
That Makefile made my day... # On SCO Unix Development System 3.2.2a, the const type qualifier does # not work correctly when using cc. The following line will cause it # to not be used and should be uncommented. Write once, run anywhere provided all the tweaking is done properly. Those were the days. EDIT: formatting.
__david__ 9y ago
Not exactly Zork 1. Zork was originally written on MIT mainframes, but when they decided to start Infocom and release the game for profit they couldn't get it all to fit on the personal computers of the time, and so they split it into 3 parts. Zork 2 had the coal mine and the Bank of Zork, I think, and Zork 3 had the endgame. They then added some extra stuff to Zork 2 and 3 that wasn't in the original mainframe version. The history of the source code is interesting. It was called Zork and written in MDL. At some point they renamed it to Dungeon, but then a little while later named it back to Zork. During the time it was called Dungeon, a DEC engineer logged into their system (open to the world on purpose so people could play the game) but instead of playing the game copied the source code off. Then they translated the game into Fortran so they could run it on PDP-11s. This source code is the descendant of that translation.
- davidjhall 9y ago
  A version of it has been ported to the z-machine ( available on almost every platform) : http://penguincentral.com/retrocomputing/zdungeon/ http://penguincentral.com/retrocomputing/zdungeon/ Also referenced here: http://ifdb.tads.org/viewgame?id=4gxk83ja4twckm6j http://ifdb.tads.org/viewgame?id=4gxk83ja4twckm6j
spilk 9y ago
Neat. compiled right up on my SunOS 4.1.4 machine with only a slight modification (dsub.c had some C++ style comments that the old BSD cc didn't like). phoenix$ zork Welcome to Dungeon. This version created 11-MAR-91. You are in an open field west of a big white house with a boarded front door. There is a small mailbox here. >
- DonHopkins 9y ago
  4.1.4? Yummy, my favorite! Is it running on real hardware or in a VM? If the former, what software do I need and how can I get an image please?
  - spilk 9y ago
    I'm running it on the real deal - a 1991-ish SPARCstation IPC. 25MHz of SPARC goodness. Most of these machines are dead because the power supply output capacitors have failed, but a fairly easy soldering job and they are back up and running. My original SCSI HD also failed (a 424MB Seagate ST1480N), but I've subbed in a SCSI2SD. Works a treat. I basically just play Nethack on it. I've also been experimenting with TeX 3.141 on it. As far as a VM, I believe it is possible to run 4.1.4 within QEMU. I haven't personally tried, but I have had success in the past running some versions of Solaris 2.x for sun4m in QEMU. I believe you can emulate a SPARCstation 5 with tcx graphics fairly well with that.

94 points by geospeck 9y ago

In http://blog.zarfhome.com/2017/08/your-load-is-too-heavy-zork-deep-reading.html http://blog.zarfhome.com/2017/08/your-load-is-too-heavy-zork... , Andrew Plotkin was pointing to an Inform 6 version of Zork by Allen Garvin , http://plover.net/~agarvin/zork1.txt http://plover.net/~agarvin/zork1.txt derived from the original decompiled Z-machine code.

homarp 9y ago
And http://plover.net/~agarvin/zorkbugs.txt http://plover.net/~agarvin/zorkbugs.txt is a list of Zork bugs.

JoeDaDude 9y ago

This was also discussed a couple of days ago: https://news.ycombinator.com/item?id=15138114 https://news.ycombinator.com/item?id=15138114

larrykwg 9y ago

reading old C like this, I always wonder how could people code like this back then but apparently it was transpiled from fortran. So I'd assume the original code looked better. I dug around and found it, for comparison here is the original rooms.f vs. rooms.c: https://paste.ubuntu.com/25458063/ https://paste.ubuntu.com/25458063/ https://github.com/mgius/zork/blob/master/rooms.c https://github.com/mgius/zork/blob/master/rooms.c Here is the full fortran code: http://gunkies.org/wiki/Zork#Source_code http://gunkies.org/wiki/Zork#Source_code

ajross 9y ago
Pretty sure the fortran was itself a port. My apocryphal memory is that the original is for some custom system, which wikipedia tells me was "MDL". The fortran was the result of it being carried to more common systems.
- ghaff 9y ago
  Yes. The Infocom games were written in MDL, which was a LISP derivative.
  - digi_owl 9y ago
    And developed on a PDP-11 almost too the end of the company...
    - abecedarius 9y ago
      Weren't they using a 10? I don't remember but it'd at least be surprising not to while they were still at MIT.
      - digi_owl 9y ago
        Ah yes, my bad. And it is not even that long since i read the history on Filfre. Guess i have been reading so much about the 11 i got the two mixed...
        abecedarius 9y ago
        The 11 had such a pretty instruction set, though it was kinda small for developing a program like Zork.
      - ghaff 9y ago
        I think they eventually had a TOPS-20.
jghn 9y ago
One of the gnarliest code bases I ever worked in was a very large C project where the inner core had been run through a f2c transpiler. Over the subsequent decade the surrounding code was a hodgepodge of people taking their own interpretations of autogenerated C code because folks didn't question why the code looked the way it did and thus they did their best to maintain the same look and feel. Oh and no one really knew how that original inner core worked, there were no docs, no oral tradition, and it was over 20 years old. While I was still working there we accumulated enough major change requests to the application that finally got the go ahead to throw the original code base out and start from scratch.
emddudley 9y ago
The download links at http://gunkies.org/wiki/Zork#Source_code http://gunkies.org/wiki/Zork#Source_code are all broken.
- larrykwg 9y ago
  atleast this one worked: http://simh.trailing-edge.com/games/dungeon.zip http://simh.trailing-edge.com/games/dungeon.zip (Bob's port to Fortran)
DonHopkins 9y ago
The original MDL source code is beautiful to read: https://github.com/itafroma/zork-mdl https://github.com/itafroma/zork-mdl
- larrykwg 9y ago
  thanks I hope thats the end of that rabbithole, that MDL almost looks like XML neat: https://github.com/itafroma/zork-mdl/blob/master/rooms.mud#L827 https://github.com/itafroma/zork-mdl/blob/master/rooms.mud#L...
  - gedy 9y ago
    Would be interesting to make a React port of this for the web, might look similar to MDL
  - chc 9y ago
    It looks exactly like Lisp to me, just with angle brackets rather than parens.
    - jcelerier 9y ago
      That's because both LISP, XML (and React) are just trees.
- pkaye 9y ago
  Honest question as someone who never got comfortable with Lisp languages. Is the code in parser.mud easy to read. One of those 100 line functions, could you jump to the middle of it and start understanding the meaning as someone familiar with C like languages? Even though I can figure out the syntax it looks like line noise to me but perhaps it is because i've not done much Lisp coding.
  - jsnell 9y ago
    I wouldn't call that code easy to read, and that's coming as someone who has actually at some point learned enough MDL to actually know the syntax rather than have to reverse engineer it on the spot. There's a couple of reasons why that code is rough to read today: - It's doing very complicated operations that operate on mutable global data, and structuring it as huge and deeply nested functions rather than splitting the operations up to smaller chunks with meaningful names. But you'd see exactly the same kind of thing in non-Lisp source code of that era; it's just different sensibilities. - The code is incredibly heavy on conditionals. Which makes sense given the problem domain: parsing a pseudo-natural language. But MDL is a language where the conditionals kind of suck. COND is basically unreadable in any Lisp, you'd very rarely see people use it today. In CL you'd have more readable options like IF, WHEN and UNLESS. In MDL the only option is misusing short-circuiting AND/OR as a poor man's IF. Which they do in places, which doesn't help readability either. - The use of angle brackets makes everything look like a sea of less-/greater -than comparisons. At least I just can't help it. It's especially bad when combined with the array indexing syntax.
michaelcampbell 9y ago
What version of c used integer and logical as type decls?

scelerat 9y ago

A cavalcade of GOTOs

contingencies 9y ago
Back then, stacks (and the private namespaces resulting from the use of functions/methods in most modern languages) were probably considered a superfluous resource indulgence: 1970s bloatware.
smegel 9y ago
Might have been ported from assembly, this is not really the very original source. As someone said, version one was for mainframe or something.
- Narishma 9y ago
  It was ported from Fortran, and that version itself was ported from the original written in a LISP derivative called MDL.

rhspeer 9y ago

It would be interesting to refactor zork into HTML+CSS and set it up like cssZenGarden.com so folks could add their own designs. Although a much smaller text adventure game would me more achievable.

lgas 9y ago
You can create HTML based interactive fiction with the latest inform: http://inform7.com/ http://inform7.com/
throwanem 9y ago
That's basically Twine: https://twinery.org https://twinery.org
- rhspeer 9y ago
  that's new to me, thanks!

SoMisanthrope 9y ago

The Zork Anthology is available for $6 on Steam.... just saying :-) I'm reliving my childhood. Used to play it on a TRS Model III. Good times!

teddyh 9y ago

See also Open Adventure: https://gitlab.com/esr/open-adventure https://gitlab.com/esr/open-adventure “This code is a forward-port of the Crowther/Woods Adventure 2.5 from 1995, last version in the main line of Colossal Cave Adventure development written by the original authors. The authors have given permission and encouragement for this release, it obsolesces all the 350-point versions and previous 2.x (430-point) ports.”

taeric 9y ago
Knuth has a version of this game. Fun read: http://www-cs-faculty.stanford.edu/~knuth/programs/advent.w.gz http://www-cs-faculty.stanford.edu/~knuth/programs/advent.w....
- svat 9y ago
  Note: Best to run that program through `cweave` and read the typeset output, rather than read the `.w` file directly.
  - taeric 9y ago
    Indeed, I should have mentioned this. Thanks! This is also a chapter in https://smile.amazon.com/Selected-Papers-Games-Lecture-Notes/dp/157586584X/ https://smile.amazon.com/Selected-Papers-Games-Lecture-Notes... I would be lying if I said this was super easy to read. It is easy, though. Not sure if it is a good exposition for literate programming. I certainly like it, but I think I was predisposed to.
    - svat 9y ago
      Yeah when reading some of Knuth's literate programs, I get the feeling that they are probably the best possible exposition of programs that are not so good to read. :-) That is, the programs aren't structured modularly like good modern programmers would write (encapsulation, separation of concerns, etc.) — instead they freely use global variables, gotos, etc., in the programming style of the 60s with some of Knuth's idiosyncratic improvements. But given that "bad" program, the one with the globals and the gotos, Knuth's literate programming system produces what is probably the best possible exposition of that program — at least for reading as printed material (on paper not on screen).

crocal 9y ago

That Makefile made my day... # On SCO Unix Development System 3.2.2a, the const type qualifier does # not work correctly when using cc. The following line will cause it # to not be used and should be uncommented. Write once, run anywhere provided all the tweaking is done properly. Those were the days. EDIT: formatting.

__david__ 9y ago

Not exactly Zork 1. Zork was originally written on MIT mainframes, but when they decided to start Infocom and release the game for profit they couldn't get it all to fit on the personal computers of the time, and so they split it into 3 parts. Zork 2 had the coal mine and the Bank of Zork, I think, and Zork 3 had the endgame. They then added some extra stuff to Zork 2 and 3 that wasn't in the original mainframe version. The history of the source code is interesting. It was called Zork and written in MDL. At some point they renamed it to Dungeon, but then a little while later named it back to Zork. During the time it was called Dungeon, a DEC engineer logged into their system (open to the world on purpose so people could play the game) but instead of playing the game copied the source code off. Then they translated the game into Fortran so they could run it on PDP-11s. This source code is the descendant of that translation.

davidjhall 9y ago
A version of it has been ported to the z-machine ( available on almost every platform) : http://penguincentral.com/retrocomputing/zdungeon/ http://penguincentral.com/retrocomputing/zdungeon/ Also referenced here: http://ifdb.tads.org/viewgame?id=4gxk83ja4twckm6j http://ifdb.tads.org/viewgame?id=4gxk83ja4twckm6j

spilk 9y ago

Neat. compiled right up on my SunOS 4.1.4 machine with only a slight modification (dsub.c had some C++ style comments that the old BSD cc didn't like). phoenix$ zork Welcome to Dungeon. This version created 11-MAR-91. You are in an open field west of a big white house with a boarded front door. There is a small mailbox here. >

DonHopkins 9y ago
4.1.4? Yummy, my favorite! Is it running on real hardware or in a VM? If the former, what software do I need and how can I get an image please?
- spilk 9y ago
  I'm running it on the real deal - a 1991-ish SPARCstation IPC. 25MHz of SPARC goodness. Most of these machines are dead because the power supply output capacitors have failed, but a fairly easy soldering job and they are back up and running. My original SCSI HD also failed (a 424MB Seagate ST1480N), but I've subbed in a SCSI2SD. Works a treat. I basically just play Nethack on it. I've also been experimenting with TeX 3.141 on it. As far as a VM, I believe it is possible to run 4.1.4 within QEMU. I haven't personally tried, but I have had success in the past running some versions of Solaris 2.x for sun4m in QEMU. I believe you can emulate a SPARCstation 5 with tcx graphics fairly well with that.