Chapter 62

[from the ADVENT game] The canonical `magic word'. This comes from ADVENT, in which the idea is to explore an underground cave with many rooms and to collect the treasures you find there. If you type `xyzzy' at the appropriate time, you can move instantly between two otherwise distant points. If, therefore, you encounter some bit of magic, you might remark on this quite succinctly by saying simply "Xyzzy!" "Ordinarily you can't look at someone else's screen if he has protected it, but if you type quadruple-bucky-clear the system will let you do it anyway." "Xyzzy!" It's traditional for xyzzy to be an Easter egg in games with text interfaces.

Xyzzy has actually been implemented as an undocumented no-op command on several OSes; in Data General's AOS/VS, for example, it would typically respond "Nothing happens", just as ADVENT did if the magic was invoked at the wrong spot or before a player had performed the action that enabled the word. In more recent 32-bit versions, by the way, AOS/VS responds "Twice as much happens".

Early versions of the popular `minesweeper' game under Microsoft Windows had a cheat mode triggered by the command `xyzzy ' that turns the top-left pixel of the screen different colors depending on whether or not the cursor is over a bomb. This feature temporarily diasappeared in Windows 98, but reappeared in Windows 2000.

The following passage from "The Wonderful Wizard of Oz" by L. Frank Baum, suggesting a possible pre-ADVENT origin, has recently come to light:

"Ziz-zy, zuz-zy, zik!" said Dorothy, who was now standing on both feet. This ended the saying of the charm, and they heard a great chattering and flapping of wings, as the band of Winged Monkeys flew up to them.

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= Y =

YA-:

YABA:

YAFIYGI:

YAUN:

Yellow Book:

yellow card:

yellow wire:

Yet Another:

YHBT:

YKYBHTLW:

YMMV:

You are not expected to understand this:

You know you've been hacking too long when:

Your mileage may vary:

Yow!:

yoyo mode:

Yu-Shiang Whole Fish:

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YA- abbrev.

[Yet Another] In hackish acronyms this almost invariably expands to Yet Another, following the precedent set by Unix yacc(1) (Yet Another Compiler-Compiler). See YABA.

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YABA /ya'b*/ n.

[Cambridge] Yet Another Bloody Acronym. Whenever some program is being named, someone invariably suggests that it be given a name that is acronymic. The response from those with a trace of originality is to remark ironically that the proposed name would then be `YABA-compatible'. Also used in response to questions like "What is WYSIWYG?" See also TLA.

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YAFIYGI /yaf'ee-y*-gee/ adj.

[coined in response to WYSIWYG] Describes the command-oriented ed/vi/nroff/TeX style of word processing or other user interface, the opposite of WYSIWYG. Stands for "You asked for it, you got it", because what you actually asked for is often not apparent until long after it is too late to do anything about it. Used to denote perversity ("Real Programmers use YAFIYGI tools...and like it!") or, less often, a necessary tradeoff ("Only a YAFIYGI tool can have full programmable flexibility in its interface.").

This precise sense of "You asked for it, you got it" seems to have first appeared in Ed Post's classic parody "Real Programmers don't use Pascal" (see Real Programmers); the acronym is a more recent invention.

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YAUN /yawn/ n.

[Acronym for `Yet Another Unix Nerd'] Reported from the San Diego Computer Society (predominantly a microcomputer users' group) as a good-natured punning insult aimed at Unix zealots.

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Yellow Book n.

The print version of this Jargon File; "The New Hacker's Dictionary" from MIT Press; The book includes essentially all the material the File, plus a Foreword by Guy L. Steele Jr. and a Preface by Eric S. Raymond. Most importantly, the book version is nicely typeset and includes almost all of the infamous Crunchly cartoons by the Great Quux, each attached to an appropriate entry. The first edition (1991, ISBN 0-262-68069-6) corresponded to the Jargon File version 2.9.6. The second edition (1993, ISBN 0-262-68079-3) corresponded to the Jargon File 3.0.0. The third (1996, ISBN 0-262-68092-0) corresponded to 4.0.0.

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yellow card n.

See green card.

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yellow wire n.

[IBM] Repair wires used when connectors (especially ribbon connectors) got broken due to some schlemiel pinching them, or to reconnect cut traces after the FE mistakenly cut one. Compare blue wire, purple wire, red wire.

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Yet Another adj.

[From Unix's yacc(1), `Yet Another Compiler-Compiler', a LALR parser generator] 1. Of your own work: A humorous allusion often used in titles to acknowledge that the topic is not original, though the content is. As in `Yet Another AI Group' or `Yet Another Simulated Annealing Algorithm'. 2. Of others' work: Describes something of which there are already far too many. See also YA-, YABA, YAUN.

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YHBT //

[Usenet: very common] Abbreviation: You Have Been Trolled (see troll, sense 1). Especially used in "YHBT. YHL. HAND.", which is widely understood to expand to "You Have Been Trolled. You Have Lost. Have A Nice Day". You are quite likely to see this if you respond incautiously to a flame-provoking post that was obviously floated as sucker bait.

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YKYBHTLW // abbrev.

Abbreviation of `You know you've been hacking too long when...', which became established on the Usenet group _alt.folklore.computers_ during extended discussion of the indicated entry in the Jargon File.

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YMMV // cav.

Abbreviation for Your mileage may vary common on Usenet.

Node:You are not expected to understand this, Next:You know you've been hacking too long when, Previous:YMMV, Up:= Y =

You are not expected to understand this [Unix] cav.

The canonical comment describing something magic or too complicated to bother explaining properly. From an infamous comment in the context-switching code of the V6 Unix kernel. Dennis Ritchie has explained this in detail.

Node:You know you've been hacking too long when, Next:Your mileage may vary, Previous:You are not expected to understand this, Up:= Y =

You know you've been hacking too long when

The set-up line for a genre of one-liners told by hackers about themselves. These include the following:

not only do you check your email more often than your paper mail, but you remember your network address faster than your postal one.

your SO kisses you on the neck and the first thing you think is "Uh, oh, priority interrupt."

you go to balance your checkbook and discover that you're doing it in octal.

your computers have a higher street value than your car.

in your universe, `round numbers' are powers of 2, not 10.

more than once, you have woken up recalling a dream in some programming language.

you realize you have never seen half of your best friends.

A list list of these can be found by searching for this phrase on the web.

[An early version of this entry said "All but one of these have been reliably reported as hacker traits (some of them quite often). Even hackers may have trouble spotting the ringer." The ringer was balancing one's checkbook in octal, which I made up out of whole cloth. Although more respondents picked that one out as fiction than any of the others, I also received multiple independent reports of its actually happening, most famously to Grace Hopper while she was working with BINAC in 1949. --ESR]

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Your mileage may vary cav.

[from the standard disclaimer attached to EPA mileage ratings by American car manufacturers] 1. A ritual warning often found in Unix freeware distributions. Translates roughly as "Hey, I tried to write this portably, but who knows what'll happen on your system?" 2. More generally, a qualifier attached to advice. "I find that sending flowers works well, but your mileage may vary."

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Yow! /yow/ interj.

[from "Zippy the Pinhead" comix] A favored hacker expression of humorous surprise or emphasis. "Yow! Check out what happens when you twiddle the foo option on this display hack!" Compare gurfle.

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yoyo mode n.

The state in which the system is said to be when it rapidly alternates several times between being up and being down. Interestingly (and perhaps not by coincidence), many hardware vendors give out free yoyos at Usenix exhibits.

Sun Microsystems gave out logoized yoyos at SIGPLAN '88. Tourists staying at one of Atlanta's most respectable hotels were subsequently treated to the sight of 200 of the country's top computer scientists testing yo-yo algorithms in the lobby.

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Yu-Shiang Whole Fish /yoo-shyang hohl fish/ n. obs.

The character gamma (extended SAIL ASCII 0001001), which with a loop in its tail looks like a little fish swimming down the page. The term is actually the name of a Chinese dish in which a fish is cooked whole (not parsed) and covered with Yu-Shiang (or Yu-Hsiang) sauce. Usage: primarily by people on the MIT LISP Machine, which could display this character on the screen. Tends to elicit incredulity from people who hear about it second-hand.

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= Z =

zap:

zapped:

Zawinski's Law:

zbeba:

zen:

zero:

zero-content:

Zero-One-Infinity Rule:

zeroth:

zigamorph:

zip:

zipperhead:

zombie:

zorch:

Zork:

zorkmid:

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zap

1. n. Spiciness. 2. vt. To make food spicy. 3. vt. To make someone `suffer' by making his food spicy. (Most hackers love spicy food. Hot-and-sour soup is considered wimpy unless it makes you wipe your nose for the rest of the meal.) See zapped. 4. vt. To modify, usually to correct; esp. used when the action is performed with a debugger or binary patching tool. Also implies surgical precision. "Zap the debug level to 6 and run it again." In the IBM mainframe world, binary patches are applied to programs or to the OS with a program called `superzap', whose file name is `IMASPZAP' (possibly contrived from I M A SuPerZAP). 5. vt. To erase or reset. 6. To fry a chip with static electricity. "Uh oh -- I think that lightning strike may have zapped the disk controller."

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zapped adj.

Spicy. This term is used to distinguish between food that is hot (in temperature) and food that is spicy-hot. For example, the Chinese appetizer Bon Bon Chicken is a kind of chicken salad that is cold but zapped; by contrast, vanilla wonton soup is hot but not zapped. See also oriental food, laser chicken. See zap, senses 1 and 2.

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Zawinski's Law

"Every program attempts to expand until it can read mail. Those programs which cannot so expand are replaced by ones which can." Coined by Jamie Zawinski (who called it the "Law of Software Envelopment") to express his belief that all truly useful programs experience pressure to evolve into toolkits and application platforms (the mailer thing, he says, is just a side effect of that). It is commonly cited, though with widely varying degrees of accuracy.

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zbeba n.

[USENET] The word `moron' in rot13. Used to describe newbies who are behaving with especial cluelessness.

Node:zen, Next:zero, Previous:zbeba, Up:= Z =

zen vt.

To figure out something by meditation or by a sudden flash of enlightenment. Originally applied to bugs, but occasionally applied to problems of life in general. "How'd you figure out the buffer allocation problem?" "Oh, I zenned it." Contrast grok, which connotes a time-extended version of zenning a system. Compare hack mode. See also guru.

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zero vt.

1. To set to 0. Usually said of small pieces of data, such as bits or words (esp. in the construction `zero out'). 2. To erase; to discard all data from. Said of disks and directories, where `zeroing' need not involve actually writing zeroes throughout the area being zeroed. One may speak of something being `logically zeroed' rather than being `physically zeroed'. See scribble.

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zero-content adj.

Syn. content-free.

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Zero-One-Infinity Rule prov.

"Allow none of foo, one of foo, or any number of foo." A rule of thumb for software design, which instructs one to not place random limits on the number of instances of a given entity (such as: windows in a window system, letters in an OS's filenames, etc.). Specifically, one should either disallow the entity entirely, allow exactly one instance (an "exception"), or allow as many as the user wants - address space and memory permitting.

The logic behind this rule is that there are often situations where it makes clear sense to allow one of something instead of none. However, if one decides to go further and allow N (for N > 1), then why not N+1? And if N+1, then why not N+2, and so on? Once above 1, there's no excuse not to allow any N; hence, infinity.

Many hackers recall in this connection Isaac Asimov's SF novel "The Gods Themselves" in which a character announces that the number 2 is impossible - if you're going to believe in more than one universe, you might as well believe in an infinite number of them.

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zeroth /zee'rohth/ adj.

First. Among software designers, comes from C's and LISP's 0-based indexing of arrays. Hardware people also tend to start counting at 0 instead of 1; this is natural since, e.g., the 256 states of 8 bits correspond to the binary numbers 0, 1, ..., 255 and the digital devices known as `counters' count in this way.

Hackers and computer scientists often like to call the first chapter of a publication `Chapter 0', especially if it is of an introductory nature (one of the classic instances was in the First Edition of K&R). In recent years this trait has also been observed among many pure mathematicians (who have an independent tradition of numbering from 0). Zero-based numbering tends to reduce fencepost errors, though it cannot eliminate them entirely.

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zigamorph /zig'*-morf/ n.

1. Hex FF (11111111) when used as a delimiter or fence character. Usage: primarily at IBM shops. 2. [proposed] n. The Unicode non-character U+FFFF (1111111111111111), a character code which is not assigned to any character, and so is usable as end-of-string. (Unicode is a 16-bit character code intended to cover all of the world's writing systems, including Latin, Greek, Cyrillic, Chinese, hiragana, katakana, Devanagari, Thai, Laotian and many other scripts - support for elvish is planned for a future release).

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zip vt.

[primarily MS-DOS] To create a compressed archive from a group of files using PKWare's PKZIP or a compatible archiver. Its use is spreading now that portable implementations of the algorithm have been written. Commonly used as follows: "I'll zip it up and send it to you." See tar and feather.

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zipperhead n.

[IBM] A person with a closed mind.

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zombie n.

[Unix] A process that has died but has not yet relinquished its process table slot (because the parent process hasn't executed a wait(2) for it yet). These can be seen in ps(1) listings occasionally. Compare orphan.

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zorch /zorch/

1. [TMRC] v. To attack with an inverse heat sink. 2. [TMRC] v. To travel, with v approaching c [that is, with velocity approaching lightspeed --ESR]. 3. [MIT] v. To propel something very quickly. "The new comm software is very fast; it really zorches files through the network." 4. [MIT] n. Influence. Brownie points. Good karma. The intangible and fuzzy currency in which favors are measured. "I'd rather not ask him for that just yet; I think I've used up my quota of zorch with him for the week." 5. [MIT] n. Energy, drive, or ability. "I think I'll punt that change for now; I've been up for 30 hours and I've run out of zorch." 6. [MIT] v. To flunk an exam or course.

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Zork /zork/ n.

The second of the great early experiments in computer fantasy gaming; see ADVENT. Originally written on MIT-DM during 1977-1979, later distributed with BSD Unix (as a patched, sourceless RT-11 FORTRAN binary; see retrocomputing) and commercialized as `The Zork Trilogy' by Infocom. The FORTRAN source was later rewritten for portability and released to Usenet under the name "Dungeon". Both FORTRAN "Dungeon" and translated C versions are available at many FTP sites. See also grue.

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zorkmid /zork'mid/ n.

The canonical unit of currency in hacker-written games. This originated in Zork but has spread to nethack and is referred to in several other games.

(Lexicon Entries End Here)

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Hacker Folklore

This appendix contains several legends and fables that illuminate the meaning of various entries in the lexicon.

The Meaning of Hack: ...and three famous ones

TV Typewriters: A Tale of Hackish Ingenuity

A Story About Magic: By Guy Steele

Some AI Koans: Wit and Wisdom of the Masters

OS and JEDGAR: Intrigue and mayhem under ITS

The Story of Mel: One of hackerdom's great myths

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The Meaning of `Hack'

"The word hack doesn't really have 69 different meanings", according to MIT hacker Phil Agre. "In fact, hack has only one meaning, an extremely subtle and profound one which defies articulation. Which connotation is implied by a given use of the word depends in similarly profound ways on the context. Similar remarks apply to a couple of other hacker words, most notably random."

Hacking might be characterized as `an appropriate application of ingenuity'. Whether the result is a quick-and-dirty patchwork job or a carefully crafted work of art, you have to admire the cleverness that went into it.

An important secondary meaning of hack is `a creative practical joke'. This kind of hack is easier to explain to non-hackers than the programming kind. Of course, some hacks have both natures; see the lexicon entries for pseudo and kgbvax. But here are some examples of pure practical jokes that illustrate the hacking spirit:

In 1961, students from Caltech (California Institute of Technology, in Pasadena) hacked the Rose Bowl football game. One student posed as a reporter and `interviewed' the director of the University of Washington card stunts (such stunts involve people in the stands who hold up colored cards to make pictures). The reporter learned exactly how the stunts were operated, and also that the director would be out to dinner later.

While the director was eating, the students (who called themselves the `Fiendish Fourteen') picked a lock and stole a blank direction sheet for the card stunts. They then had a printer run off 2300 copies of the blank. The next day they picked the lock again and stole the master plans for the stunts -- large sheets of graph paper colored in with the stunt pictures. Using these as a guide, they made new instructions for three of the stunts on the duplicated blanks. Finally, they broke in once more, replacing the stolen master plans and substituting the stack of diddled instruction sheets for the original set.

The result was that three of the pictures were totally different. Instead of `WASHINGTON', the word ``CALTECH' was flashed. Another stunt showed the word `HUSKIES', the Washington nickname, but spelled it backwards. And what was supposed to have been a picture of a husky instead showed a beaver. (Both Caltech and MIT use the beaver -- nature's engineer -- as a mascot.)

After the game, the Washington faculty athletic representative said: "Some thought it ingenious; others were indignant." The Washington student body president remarked: "No hard feelings, but at the time it was unbelievable. We were amazed."

This is now considered a classic hack, particularly because revising the direction sheets constituted a form of programming.

Here is another classic hack:

On November 20, 1982, MIT hacked the Harvard-Yale football game. Just after Harvard's second touchdown against Yale, in the first quarter, a small black ball popped up out of the ground at the 40-yard line, and grew bigger, and bigger, and bigger. The letters `MIT' appeared all over the ball. As the players and officials stood around gawking, the ball grew to six feet in diameter and then burst with a bang and a cloud of white smoke.

The "Boston Globe" later reported: "If you want to know the truth, MIT won The Game."

The prank had taken weeks of careful planning by members of MIT's Delta Kappa Epsilon fraternity. The device consisted of a weather balloon, a hydraulic ram powered by Freon gas to lift it out of the ground, and a vacuum-cleaner motor to inflate it. They made eight separate expeditions to Harvard Stadium between 1 and 5 A.M., locating an unused 110-volt circuit in the stadium and running buried wires from the stadium circuit to the 40-yard line, where they buried the balloon device. When the time came to activate the device, two fraternity members had merely to flip a circuit breaker and push a plug into an outlet.

This stunt had all the earmarks of a perfect hack: surprise, publicity, the ingenious use of technology, safety, and harmlessness. The use of manual control allowed the prank to be timed so as not to disrupt the game (it was set off between plays, so the outcome of the game would not be unduly affected). The perpetrators had even thoughtfully attached a note to the balloon explaining that the device was not dangerous and contained no explosives.

Harvard president Derek Bok commented: "They have an awful lot of clever people down there at MIT, and they did it again." President Paul E. Gray of MIT said: "There is absolutely no truth to the rumor that I had anything to do with it, but I wish there were."

The hacks above are verifiable history; they can be proved to have happened. Many other classic-hack stories from MIT and elsewhere, though retold as history, have the characteristics of what Jan Brunvand has called `urban folklore' (see FOAF). Perhaps the best known of these is the legend of the infamous trolley-car hack, an alleged incident in which engineering students are said to have welded a trolley car to its tracks with thermite. Numerous versions of this have been recorded from the 1940s to the present, most set at MIT but at least one very detailed version set at CMU.