Crowther's Original Adventure Source Code Found

drxenos writes "I don't know how many of you are fans of old-school text adventures (interactive fiction), but Will Crowther's original Fortran source code has been located in a backup of Don Woods's old student account. For fans like me, this is like finding the Holy Grail."

A good example of how coding has progressed

[by Anonymous Coward]

Increased memory (both RAM & Disc storage) availability has allowed us to make our code more readable.
I looked at the various FORTRAN files and am amazed at the spaghetti GOTO maze which, although messy, was probably the only way to do things in FORTRAN at the time with no structuring capability.

A random example:

IF(K.NE.1) MASK1="177*M2(K)
        IF(((A(J).XOR."201004020100).AND.MASK1).EQ.0)GOTO 3
        IF(S.EQ.0) GOTO 2

Wow! Is that the opposite of self-documenting code or what?

Re:A good example of how coding has progressed

[SIGBUS (8236)]

So maybe the inspiration for the "maze of twisty little passages, all alike" wasn't Mammoth Cave, it was the code itself.

Re:A good example of how coding has progressed

[morgan_greywolf (835522)]

Um, could you repost that please? It seems your original post got corrupted somehow. All I see is gibberish where the code should be.

Re:A good example of how coding has progressed,

[junge_m (410514)]

This is why the grandmaster of 'Literate Programming', Donald Knuth, has done a translation into his CWEB Language which is totaly devoid of jumps and other 'dirty' Fortan:
http://www.literateprogramming.com/adventure.pdf [literateprogramming.com]

Re:A good example of how coding has progressed

[fm6 (162816)]

Memory is not the issue here. Turbo Pascal was designed to run in a single 64K 8086 segment, and Pascal is the quintessential block-structured language. The real problem is that the designers of FORTRAN were totally ignorant of the principles of language design. They could hardly be otherwise: FORTRAN was the very first high-level language.

But here's a sobering thought: Dijkstra launched his attack on the goto statement [acm.org] in 1968. Every programmer who's grown up with block structured languages would take it as a given that Dijkstra was right. But at the time, the concept was extremely controversial, and there was a lot of resistance — as evidenced by the fact that Crowther and Wood were still using computed gotos in 1976!

Re:A good example of how coding has progressed

[russotto (537200)]

The code you're quoting isn't grossly messy because of the GOTO statements. It's grossly messy because PDP-10 Fortran didn't have a CHARACTER type -- instead, you could pack 5 characters to a 36-bit integer, with the low-bit unused. The M2 array contained integer masks with one bit set, the low bit of one of the characters. Multiplying that mask by octal 177 got you a mask which selected a single character, except for the first character where the multiplication would overflow. The octal constant 201004020100 is 5 space characters. The "S" flag indicated whether a space had been found yet.

So the little snippet you posted goes to label 3 if the current character (selected by J for the integer and K for the character within the integer) is a space, and to 2 if no space has been found yet, and continues without branching if a space has been found but the current character is not a space.

If A were, more sensibly, a character array, the above would be written as

                IF(A(J:J).EQ.' ')GOTO 3
                IF(S.EQ.0) GOTO 2

which is no problem to read at all, despite the gotos.

Re:A good example of how coding has progressed

[LMacG (118321)]

Ah, the old computed GOTO. In the first line, the value of KQ is used as an index to the list of labels. If KQ=1, GOTO 5014, if KQ=2, GOTO 5000, etc. etc. If KQ is outside the range (0 or greater than 4), then no GOTO is performed, so you'd hit the PAUSE statement. Looks like it's essentially saying "this shouldn't happen".

2027 is similar, there's just a lot more possible values. That rogue 1 is a continuation indicator, it would have been in column 6 on your punch card.

Found? When was it lost?

[Smallpond (221300)]

I once wrote a script to find and delete copies of this and the star trek game due to the limited disk space on our PDP-11/70. It had to compare file contents because the sneaky bastards would change the file names to something like TPSRPORT.DOC to hide them.

at last!

[pbjones (315127)]

I may print it out and use it for wall paper. or etch it on silicon.

History - Looking for Scheme tarball 1986-87 era

[scottsk (781208)]

The adventure source is a great find. I've been looking for the Scheme source tarball from the 1986-1987 period (i.e. when SICP was still new) for over a year, with no success. The changelog is online, and shows the work that was done in that period, but none of the tarballs still exists. Anyone have a Scheme distribution tarball from late 1987? I would like to run the code from that time along with the book to do screen captures, etc for something I'm working on.

EAMON!!!!

[WED Fan (911325)]

This was fun. I remember running it on a teletype terminal in programming class (damn, thats old) BANG BANG BANG BANG BANG. You couldn't do a quick CLS to hide the evidence when the instructor came by, "Do you think paper grows on trees?" he yell. Of course all was forgiven when we showed him our course work was done. Then, he made us write our own dungeon code.

Much later, Don Brown(?) came out with EAMON [wikipedia.org], with a write your own framework. Fun fun fun.

Original Zork source code in MDL

[SimHacker (180785)]

Zork was the reason I got on the ARPANET, back around 1980 or so. I was using Bruce's Northstar BBS that had an adventure game that Bruce had written in Basic, and he told me how to play Zork: first, dial up the NBS TIP, connect to MIT-AI (the command was "@L 134", because the ARPANET had 8 bit host numbers, and AI was 134), and apply for an account to learn Lisp. Once that was granted, I connected to MIT-DM ("@L 70"), and logged in as URANUS, password RINGS, used :CHUNAME to change my user name, and waited until one of the two people playing Zork quit, to take their slot. Later somebody told me the magic words to use to get an account on DM, so I applied for my own account on DM, claiming that I wanted to "Learn MDL for calculus and algebraic applications". The source code to Zork was well hidden. DM ran a weird version of ITS that had some kind of file security or cloaking, it was rumored. I was always looking for the Zork sources, but never found it on DM.

Years later I googled for a unique phrase that was only in the original DM version of Zork, and this URL popped up: http://retro.co.za/adventure/zork-mdl/ [retro.co.za]

The original MDL source to Zork is really beautiful code that's almost as fun to read as it was to play. I had discovered a bug in the InfoCom version of Zork, which turned out to be in the original sources. When you're fighting the troll who's wielding an Axe, you can give anything to the troll and he will eat it. So I tried "give axe to troll" and he ate his axe, then cowered in the corner! Better yet you can go "give troll to troll" and he will eat himself and disappear, unfortunately not clearing the troll flag that is required to leave the room, so if you try to leave it prints a message saying the troll fends you off with a menacing gesture, and stops you from leaving. Sure enough, in the original sources [retro.co.za], there is a troll flag!

-Don

Re:Original Zork source code in MDL

[Just Some Guy (3352)]

I wore an onion on my belt

That was a great story the last time you told it [slashdot.org], too.

Re:This sounds familiar

[Barny (103770)]

GIT OFFA MAH LAWN! /me waves a shotgun around menacingly

Reversed causation

[dazedNconfuzed (154242)]

Those interactive books came about because of Adventure.

Re:This sounds familiar

[Xiaran (836924)]

My first expose to Collosal Cave was when I was about 10ish... my Dad was a programmer(mainframes... mostly IBM, sperry etc) and I played it on a Sperry mainframe terminal. It may be hard to imagine for someone like yourself that has probably grown up with high resolution, high powered desktop PCs... but playing it for me was eye opening in the extreme. I suspect Im not alone and many other got hooked on development and technology because of interactive stuff like the good old original adventure.

xyzzy

Re:This sounds familiar

[Targon (17348)]

In an era where there were no computer graphics at all, text was the only thing available. And it was a lot of fun as well.

The original Zork games, as well as the rest of the Infocom games were inspired by Adventure to a large degree. It should be noted that because they were text based, some things that would be considered obvious were not necessarily obvious in those days, which added to the puzzle solving aspect of the game.

These days, everything is made almost too obvious, because too many potential customers don't like a challenge(note that many games can be beaten straight out of the box in under 24 hours of playing). Back in those days, a game could take weeks of playing to figure out what to do, beating your head against a problem for several days before a solution would present itself wasn't uncommon.

Then again, it seems that too many people never bother to pick up a book when movies are available, and never realize how horribly the film makers have screwed up a great story, so it's no wonder some people would never understand why text adventures were fun.

Re:Why it was special...

[ian_mackereth (889101)]

I encountered it as an engineering undergrad, on a university Cyber 204 or 205 mainframe, the first computer I'd ever used. I had to hack extra console time via various means to complete it, using a mega flowchart I drew up as I went.

When I finally finished it, the screen cleared and an operator in the computer centre was typing to me and asking me to come over to the centre. I figured I'd been sprung for all the extra time I'd 'arranged', but instead they gave me printout and iducted me into the Order of Wizards!

A nerdy proud moment... (I wish I hadn't lost that printout in the intervening decades and moves.)

Re:THIS IS A HOAX

[pla (258480)]

Who else would call FORTRAN a "text adventure"?

Well, calling it a "programming language" certainly qualifies as "fantasy"... ;-)



/ Props to HPF, though
// Still wouldn't use it unless forced to at gunpoint

The Fortran gods shall smite thee

[White Yeti (927387)]

program smite_em
c-----
      IMPLICIT NONE      ! Catch typos and un-initialized variables.
      integer       IERR_smite
      character*200 ch_name
c-----
      write(6,1)
1     FORMAT(/,' This is one smiting program!',/,
     &   '   Enter name of smitee --> ',$)
      read(*,fmt='(A)') ch_name

      DO while(.TRUE.)   ! Endless smiting loop.
         call smite(ch_name, IERR_smite)
         if(IERR_smite.GT.0) goto 20
      End DO             ! smite loop.
20    CONTINUE

      write(*,*)' Done smiting.'
      if(IERR_smite.LT.0) then
         write(6,2) IERR_smite
2        FORMAT(' ***Possible smiting error, IERR_smite = ',I)
      endif
      STOP
      END
c-----
c End of Main.
c-----

Re:Wow....

[PrescriptionWarning (932687)]

Q: "What is your quest?"

A> "To Seek the holy grail!"

Q: "what is your favorite text base adventure game?"

A> "Colossal Cave Adventure... NO wait, blue!"

*Gets launched into the death pit*

   tttttt
  t      t
t          t
t   R I P  t
t          t
t          t
tttttttttttt

Re:Wow....

[by Anonymous Coward]

"Someone mind finishing the work for me?"

Fine, fine.

For fans like me, this is like finding the Holy Grail.

Drxenos! Drxenos, King of the Nerds! Oh, don't grovel! If there's one thing I can't stand, it's people groveling! ...
[slightly later]

Behold! Drxenos, this is the Holy Grail of Computer Games. Look well, drxenos, for it is your sacred task to seek this Grail. That is your purpose, drxenos -- the Quest for the Holy Grail of Computer Games: Adventure. And it is written in FORTRAN.

Wait, FORTRAN? Lord, you're kidding right?

[significantly later]

He says they've already got one!

Yes, it's-a verry nice-a. It is-a coded in C.

[substantially later]

We are the Knights Who Say ... IP! IP! IP!

Augh!!!! Stop it!

[much later]

What is the net speed of an unladen TCP/IP data packet using PPP over a 1200 baud modem?
What do you mean? With or without parity, 7 or 8 bits, with or without flow control?
What? I don't know all that! Auuuuuugh!!!

[slightly later but a little further that the previously-mentioned "slightly later"]

The Castle Stanford. Once we brave its maze of twisty little passages, all alike, our quest is at an end!

Re:I must not be old enough

[Mr. Slippery (47854)]

what the fuck does rock-climbing have to do with "ethics"?

The same thing leaving a campsite better than you found it has to do with ethics, or not littering has to do with ethics. Altering the environment and depriving others of potential experiences is an ethical issue.

A quick Googling [google.com] will reveal that "climbing ethics" is not an invention of the Wikipedia author, but is an active area of discussion among climbers.

Re:Wait for the Game...

[spun (1352)]

You are in a debris room filled with stuff washed in from the surface. A low wide passage with cobbles becomes plugged with mud and debris here, but an awkward canyon leads upward and west. There is a PDP-10 with a card reader and terminal here. A box of punchcards sits nearby.
> get box
You now have the box of punchcards.
> input cards
You carefully feed the cards into the card reader.
> look terminal
The terminal says:
YOU ARE STANDING AT THE END OF A ROAD BEFORE A SMALL BRICK
BUILDING. AROUND YOU IS A FOREST. A SMALL
STREAM FLOWS OUT OF THE BUILDING AND DOWN A GULLY.

Re:Is it just me...?

[drxenos (573895)]

I think you are looking at it from the wrong perspective. Do not look at its merits as a program, especially when compared to modern day games. Imagine you were a coin collector, and happened across an old coin thought to not even exist anymore. Or a comic collector finding a MINT copy of Detective #27 (there are no known mint copies). That is what it is like for me as a collector. Granted it does not have the monetary value of my examples, but money is not the point. It the historical value, and nostalgia for me.