:tits on a keyboard: n. Small bumps on certain keycaps to keep touch-typists registered (usually on the '5' of a numeric keypad, and on the 'F' and 'J' of a QWERTY keyboard; but the Mac, perverse as usual, has them on the 'D' and 'K' keys).

:TLA: /T-L-A/ [Three-Letter Acronym] n. 1. Self-describing abbreviation for a species with which computing terminology is infested. 2. Any confusing acronym. Examples include MCA, FTP, SNA, CPU, MMU, SCCS, DMU, FPU, NNTP, TLA. People who like this looser usage argue that not all TLAs have three letters, just as not all four-letter words have four letters. One also hears of 'ETLA' (Extended Three-Letter Acronym, pronounced /ee tee el ay/) being used to describe four-letter acronyms. The term 'SFLA' (Stupid Four-Letter Acronym) has also been reported. See also {YABA}.

The self-effacing phrase "TDM TLA" (Too Damn Many...) is often used to bemoan the plethora of TLAs in use. In 1989, a random of the journalistic persuasion asked hacker Paul Boutin "What do you think will be the biggest problem in computing in the 90s?" Paul's straight-faced response: "There are only 17,000 three-letter acronyms." (To be exact, there are 26^3 = 17,576.)

:TMRC: /tmerk'/ n. The Tech Model Railroad Club at MIT, one of the wellsprings of hacker culture. The 1959 'Dictionary of the TMRC Language' compiled by Peter Samson included several terms which became basics of the hackish vocabulary (see esp. {foo} and {frob}).

By 1962, TMRC's legendary layout was already a marvel of complexity (and has grown in the thirty years since; all the features described here are still present). The control system alone featured about 1200 relays. There were {scram switch}es located at numerous places around the room that could be thwacked if something undesirable was about to occur, such as a train going full-bore at an obstruction. Another feature of the system was a digital clock on the dispatch, board, which was itself something of a wonder in those bygone days before cheap LEDS and seven-segment displays (no model railroad can begin to approximate the scale distances between towns and stations, so model railroad timetables assume a fast clock so that it seems to take about the right amount of time for a train to complete its journey). When someone hit a scram switch the clock stopped and the display was replaced with the word 'FOO'; at TMRC the scram switches are therefore called 'foo switches'.

Steven Levy, in his book 'Hackers' (see the Bibliography in {appendix C}), gives a stimulating account of those early years. TMRC's Power and Signals group included most of the early PDP-1 hackers and the people who later bacame the core of the MIT AI Lab staff. Thirty years later that connection is still very much alive, and this lexicon accordingly includes a number of entries from a recent revision of the TMRC Dictionary.

:TMRCie: /tmerk'ee/, /tuh-merk'ee/ [MIT] n. A denizen of {TMRC}.

:to a first approximation: 1. [techspeak] When one is doing certain numerical computations, an approximate solution may be computed by any of several heuristic methods, then refined to a final value. By using the starting point of a first approximation of the answer, one can write an algorithm that converges more quickly to the correct result. 2. In jargon, a preface to any comment that indicates that the comment is only approximately true. The remark "To a first approximation, I feel good" might indicate that deeper questioning would reveal that not all is perfect (e.g., a nagging cough still remains after an illness).

:to a zeroth approximation: [from 'to a first approximation'] A *really* sloppy approximation; a wild guess. Compare {social science number}.

:toast: 1. n. Any completely inoperable system or component, esp. one that has just crashed and burned: "Uh, oh ... I think the serial board is toast." 2. vt. To cause a system to crash accidentally, especially in a manner that requires manual rebooting. "Rick just toasted the {firewall machine} again."

:toaster: n. 1. The archetypal really stupid application for an embedded microprocessor controller; often used in comments that imply that a scheme is inappropriate technology (but see {elevator controller}). "{DWIM} for an assembler? That'd be as silly as running UNIX on your toaster!" 2. A very, very dumb computer. "You could run this program on any dumb toaster." See {bitty box}, {Get a real computer!}, {toy}, {beige toaster}. 3. A Macintosh, esp. the Classic Mac. Some hold that this is implied by sense 2. 4. A peripheral device. "I bought my box without toasters, but since then I've added two boards and a second disk drive."

:toeprint: n. A {footprint} of especially small size.

:toggle: vt. To change a {bit} from whatever state it is in to the other state; to change from 1 to 0 or from 0 to 1. This comes from 'toggle switches', such as standard light switches, though the word 'toggle' actually refers to the mechanism that keeps the switch in the position to which it is flipped rather than to the fact that the switch has two positions. There are four things you can do to a bit: set it (force it to be 1), clear (or zero) it, leave it alone, or toggle it. (Mathematically, one would say that there are four distinct boolean-valued functions of one boolean argument, but saying that is much less fun than talking about toggling bits.)

:tool: 1. n. A program used primarily to create, manipulate, modify, or analyze other programs, such as a compiler or an editor or a cross-referencing program. Oppose {app}, {operating system}. 2. [UNIX] An application program with a simple, 'transparent' (typically text-stream) interface designed specifically to be used in programmed combination with other tools (see {filter}). 3. [MIT: general to students there] vi. To work; to study (connotes tedium). The TMRC Dictionary defined this as "to set one's brain to the grindstone". See {hack}. 4. [MIT] n. A student who studies too much and hacks too little. (MIT's student humor magazine rejoices in the name 'Tool and Die'.)

:toolsmith: n. The software equivalent of a tool-and-die specialist; one who specializes in making the {tool}s with which other programmers create applications. Many hackers consider this more fun than applications per se; to understand why, see {uninteresting}. Jon Bentley, in the "Bumper-Sticker Computer Science" chapter of his book 'More Programming Pearls', quotes Dick Sites from DEC as saying "I'd rather write programs to write programs than write programs".

:topic drift: n. Term used on GEnie, USENET and other electronic fora to describe the tendency of a {thread} to drift away from the original subject of discussion (and thus, from the Subject header of the originating message), or the results of that tendency. Often used in gentle reminders that the discussion has strayed off any useful track. "I think we started with a question about Niven's last book, but we've ended up discussing the sexual habits of the common marmoset. Now *that's* topic drift!"

:topic group: n. Syn. {forum}.

:TOPS-10:: /tops-ten/ n. DEC's proprietary OS for the fabled {PDP-10} machines, long a favorite of hackers but now effectively extinct. A fountain of hacker folklore; see {appendix A}. See also {{ITS}}, {{TOPS-20}}, {{TWENEX}}, {VMS}, {operating system}. TOPS-10 was sometimes called BOTS-10 (from 'bottoms-ten') as a comment on the inappropriateness of describing it as the top of anything.

:TOPS-20:: /tops-twen'tee/ n. See {{TWENEX}}.

:toto: /toh'toh/ n. This is reported to be the default scratch file name among French-speaking programmers —- in other words, a francophone {foo}. It is reported that the phonetic mutations "titi", "tata", and "tutu" canonically follow 'toto', analogously to {bar}, {baz} and {quux} in English.

:tourist: [ITS] n. A guest on the system, especially one who generally logs in over a network from a remote location for {comm mode}, email, games, and other trivial purposes. One step below {luser}. Hackers often spell this {turist}, perhaps by some sort of tenuous analogy with {luser} (this also expresses the ITS culture's penchant for six-letterisms). Compare {twink}, {read-only user}.

:tourist information: n. Information in an on-line display that is not immediately useful, but contributes to a viewer's gestalt of what's going on with the software or hardware behind it. Whether a given piece of info falls in this category depends partly on what the user is looking for at any given time. The 'bytes free' information at the bottom of an MS-DOS 'dir' display is tourist information; so (most of the time) is the TIME information in a UNIX 'ps(1)' display.

:touristic: adj. Having the quality of a {tourist}. Often used as a pejorative, as in 'losing touristic scum'. Often spelled 'turistic' or 'turistik', so that phrase might be more properly rendered 'lusing turistic scum'.

:toy: n. A computer system; always used with qualifiers. 1. 'nice toy': One that supports the speaker's hacking style adequately. 2. 'just a toy': A machine that yields insufficient {computron}s for the speaker's preferred uses. This is not condemnatory, as is {bitty box}; toys can at least be fun. It is also strongly conditioned by one's expectations; Cray XMP users sometimes consider the Cray-1 a 'toy', and certainly all RISC boxes and mainframes are toys by their standards. See also {Get a real computer!}.

:toy language: n. A language useful for instructional purposes or as a proof-of-concept for some aspect of computer-science theory, but inadequate for general-purpose programming. {Bad Thing}s can result when a toy language is promoted as a general purpose solution for programming (see {bondage-and-discipline language}); the classic example is {{Pascal}}. Several moderately well-known formalisms for conceptual tasks such as programming Turing machines also qualify as toy languages in a less negative sense. See also {MFTL}.

:toy problem: [AI] n. A deliberately oversimplified case of a challenging problem used to investigate, prototype, or test algorithms for a real problem. Sometimes used pejoratively. See also {gedanken}, {toy program}.

:toy program: n. 1. One that can be readily comprehended; hence, a trivial program (compare {noddy}). 2. One for which the effort of initial coding dominates the costs through its life cycle. See also {noddy}.

:trampoline: n. An incredibly {hairy} technique, found in some {HLL} and program-overlay implementations (e.g., on the Macintosh), that involves on-the-fly generation of small executable (and, likely as not, self-modifying) code objects to do indirection between code sections. These pieces of {live data} are called 'trampolines'. Trampolines are notoriously difficult to understand in action; in fact, it is said by those who use this term that the trampoline that doesn't bend your brain is not the true trampoline. See also {snap}.

:trap: 1. n. A program interrupt, usually an interrupt caused by some exceptional situation in the user program. In most cases, the OS performs some action, then returns control to the program. 2. vi. To cause a trap. "These instructions trap to the monitor." Also used transitively to indicate the cause of the trap. "The monitor traps all input/output instructions."

This term is associated with assembler programming ('interrupt' or 'exception' is more common among {HLL} programmers) and appears to be fading into history among programmers as the role of assembler continues to shrink. However, it is still important to computer architects and systems hackers (see {system}, sense 1), who use it to distinguish deterministically repeatable exceptions from timing-dependent ones (such as I/O interrupts).

:trap door: alt. 'trapdoor' n. 1. Syn. {back door} —- a {Bad Thing}. 2. [techspeak] A 'trap-door function' is one which is easy to compute but very difficult to compute the inverse of. Such functions are {Good Thing}s with important applications in cryptography, specifically in the construction of public-key cryptosystems.

:trash: vt. To destroy the contents of (said of a data structure). The most common of the family of near-synonyms including {mung}, {mangle}, and {scribble}.

:trawl: v. To sift through large volumes of data (e.g. USENET postings or FTP archives) looking for something of interest.

:tree-killer: [Sun] n. 1. A printer. 2. A person who wastes paper. This should be interpreted in a broad sense; 'wasting paper' includes the production of {spiffy} but {content-free} documents. Thus, most {suit}s are tree-killers. The negative loading of this term may reflect the epithet 'tree-killer' applied by Treebeard the Ent to the Orcs in J.R.R. Tolkien's 'Lord of the Rings' trilogy (see also {elvish}, {elder days}).

:trit: /trit/ [by analogy with 'bit'] n. One base-3 digit; the amount of information conveyed by a selection among one of three equally likely outcomes (see also {bit}). These arise, for example, in the context of a {flag} that should actually be able to assume *three* values —- such as yes, no, or unknown. Trits are sometimes jokingly called '3-state bits'. A trit may be semi-seriously referred to as 'a bit and a half', although it is linearly equivalent to 1.5849625 bits (that is, log2(3) bits).

:trivial: adj. 1. Too simple to bother detailing. 2. Not worth the speaker's time. 3. Complex, but solvable by methods so well known that anyone not utterly {cretinous} would have thought of them already. 4. Any problem one has already solved (some claim that hackish 'trivial' usually evaluates to 'I've seen it before'). Hackers' notions of triviality may be quite at variance with those of non-hackers. See {nontrivial}, {uninteresting}.

:troff: /tee'rof/ or /trof/ [UNIX] n. The gray eminence of UNIX text processing; a formatting and phototypesetting program, written originally in PDP-11 assembler and then in barely-structured early C by the late Joseph Ossana, modeled after the earlier ROFF which was in turn modeled after Multics' RUNOFF. A companion program, 'nroff', formats output for terminals and line printers.

In 1979, Brian Kernighan modified TROFF so that it could drive phototypesetters other than the Graphic Systems CAT. His paper describing that work ("A Typesetter-independent TROFF," AT&T CSTR #97) explains 'troff''s durability. After discussing the program's "obvious deficiencies —- a rebarbative input syntax, mysterious and undocumented properties in some areas, and a voracious appetite for computer resources" and noting the ugliness and extreme hairiness of the code and internals, Kernighan concludes:

None of these remarks should be taken as denigrating Ossana's accomplishment with TROFF. It has proven a remarkably robust tool, taking unbelievable abuse from a variety of preprocessors and being forced into uses that were never conceived of in the original design, all with considerable grace under fire.

The success of TeX and desktop publishing systems have reduced 'troff''s relative importance, but this tribute perfectly captures the strengths that secured 'troff' a place in hacker folklore; indeed, it could be taken more generally as an indication of those qualities of good programs which, in the long run, hackers most admire.

:troglodyte: [Commodore] n. 1. A hacker who never leaves his cubicle. The term 'Gnoll' (from Dungeons & Dragons) is also reported. 2. A curmudgeon attached to an obsolescent computing environment. The combination 'ITS troglodyte' was flung around some during the USENET and email wringle-wrangle attending the 2.x.x revision of the Jargon File; at least one of the people it was intended to describe adopted it with pride.

:troglodyte mode: [Rice University] n. Programming with the lights turned off, sunglasses on, and the terminal inverted (black on white) because you've been up for so many days straight that your eyes hurt (see {raster burn}). Loud music blaring from a stereo stacked in the corner is optional but recommended. See {larval stage}, {hack mode}.

:Trojan horse: [coined by MIT-hacker-turned-NSA-spook Dan Edwards] n. A program designed to break security or damage a system that is disguised as something else benign, such as a directory lister, archiver, a game, or (in one notorious 1990 case on the Mac) a program to find and destroy viruses! See {back door}, {virus}, {worm}.

:tron: [NRL, CMU; prob. fr. the movie 'Tron'] v. To become inaccessible except via email or 'talk(1)', especially when one is normally available via telephone or in person. Frequently used in the past tense, as in: "Ran seems to have tronned on us this week" or "Gee, Ran, glad you were able to un-tron yourself". One may also speak of 'tron mode'.

:true-hacker: [analogy with 'trufan' from SF fandom] n. One who exemplifies the primary values of hacker culture, esp. competence and helpfulness to other hackers. A high compliment. "He spent 6 hours helping me bring up UUCP and netnews on my FOOBAR 4000 last week —- manifestly the act of a true-hacker." Compare {demigod}, oppose {munchkin}.

:tty: /T-T-Y/ [UNIX], /tit'ee/ [ITS, but some UNIX people say it this way as well; this pronunciation is not considered to have sexual undertones] n. 1. A terminal of the teletype variety, characterized by a noisy mechanical printer, a very limited character set, and poor print quality. Usage: antiquated (like the TTYs themselves). See also {bit-paired keyboard}. 2. [especially UNIX] Any terminal at all; sometimes used to refer to the particular terminal controlling a given job. 3. [UNIX] Any serial port, whether or not the device connected to it is a terminal; so called because under UNIX such devices have names of the form tty*. Ambiguity between senses 2 and 3 is common but seldom bothersome.

:tube: 1. n. A CRT terminal. Never used in the mainstream sense of TV; real hackers don't watch TV, except for Loony Toons, Rocky & Bullwinkle, Trek Classic, the Simpsons, and the occasional cheesy old swashbuckler movie (see {appendix B}). 2. [IBM] To send a copy of something to someone else's terminal. "Tube me that note?"

:tube time: n. Time spent at a terminal or console. More inclusive than hacking time; commonly used in discussions of what parts of one's environment one uses most heavily. "I find I'm spending too much of my tube time reading mail since I started this revision."

:tunafish: n. In hackish lore, refers to the mutated punchline of an age-old joke to be found at the bottom of the manual pages of 'tunefs(8)' in the original {BSD} 4.2 distribution. The joke was removed in later releases once commercial sites started using 4.2. Tunefs relates to the 'tuning' of file-system parameters for optimum performance, and at the bottom of a few pages of wizardly inscriptions was a 'BUGS' section consisting of the line "You can tune a file system, but you can't tunafish". Variants of this can be seen in other BSD versions, though it has been excised from some versions by humorless management {droid}s. The [nt]roff source for SunOS 4.1.1 contains a comment apparently designed to prevent this: "Take this out and a Unix Demon will dog your steps from now until the 'time_t''s wrap around."

:tune: [from automotive or musical usage] vt. To optimize a program or system for a particular environment, esp. by adjusting numerical parameters designed as {hook}s for tuning, e.g., by changing '#define' lines in C. One may 'tune for time' (fastest execution), 'tune for space' (least memory use), or 'tune for configuration' (most efficient use of hardware). See {bum}, {hot spot}, {hand-hacking}.

:turbo nerd: n. See {computer geek}.

:Turing tar-pit: n. 1. A place where anything is possible but nothing of interest is practical. Alan Turing helped lay the foundations of computer science by showing that all machines and languages capable of expressing a certain very primitive set of operations are logically equivalent in the kinds of computations they can carry out, and in principle have capabilities that differ only in speed from those of the most powerful and elegantly-designed computers. However, no machine or language exactly matching Turing's primitive set has ever been built (other than possibly as a classroom exercise), because it would be horribly slow and far too painful to use. A 'Turing tar-pit' is any computer language or other tool which shares this property. That is, it's theoretically universal —- but in practice, the harder you struggle to get any real work done, the deeper its inadequacies suck you in. Compare {bondage-and-discipline language}. 2. The perennial {holy wars} over whether language A or B is the "most powerful".

:turist: /too'rist/ n. Var. sp. of {tourist}, q.v. Also in adjectival form, 'turistic'. Poss. influenced by {luser} and 'Turing'.

:tweak: vt. 1. To change slightly, usually in reference to a value. Also used synonymously with {twiddle}. If a program is almost correct, rather than figure out the precise problem you might just keep tweaking it until it works. See {frobnicate} and {fudge factor}; also see {shotgun debugging}. 2. To {tune} or {bum} a program; preferred usage in the U.K.

:tweeter: [University of Waterloo] n. Syn. {perf}, {chad} (sense 1). This term (like {woofer}) has been in use at Waterloo since 1972, but is elsewhere unknown. In audio jargon, the word refers to the treble speaker(s) on a hi-fi.

:TWENEX:: /twe'neks/ n. The TOPS-20 operating system by DEC —- the second proprietary OS for the PDP-10 —- preferred by most PDP-10 hackers over TOPS-10 (that is, by those who were not {{ITS}} or {{WAITS}} partisans). TOPS-20 began in 1969 as Bolt, Beranek & Newman's TENEX operating system using special paging hardware. By the early 1970s, almost all of the systems on the ARPANET ran TENEX. DEC purchased the rights to TENEX from BBN and began work to make it their own. The first in-house code name for the operating system was VIROS (VIRtual memory Operating System); when customers started asking questions, the name was changed to SNARK so DEC could truthfully deny that there was any project called VIROS. When the name SNARK became known, the name was briefly reversed to become KRANS; this was quickly abandoned when it was discovered that 'krans' meant 'funeral wreath' in Swedish. Ultimately DEC picked TOPS-20 as the name of the operating system, and it was as TOPS-20 that it was marketed. The hacker community, mindful of its origins, quickly dubbed it {{TWENEX}} (a contraction of 'twenty TENEX'), even though by this point very little of the original TENEX code remained (analogously to the differences between AT&T V6 UNIX and BSD). DEC people cringed when they heard "TWENEX", but the term caught on nevertheless (the written abbreviation '20x' was also used). TWENEX was successful and very popular; in fact, there was a period in the early 1980s when it commanded as fervent a culture of partisans as UNIX or ITS —- but DEC's decision to scrap all the internal rivals to the VAX architecture and its relatively stodgy VMS OS killed the DEC-20 and put a sad end to TWENEX's brief day in the sun. DEC attempted to convince TOPS-20 hackers to convert to {VMS}, but instead, by the late 1980s, most of the TOPS-20 hackers had migrated to UNIX.

:twiddle: n. 1. Tilde (ASCII 1111110, '~'). Also called 'squiggle', 'sqiggle' (sic —- pronounced /skig'l/), and 'twaddle', but twiddle is the most common term. 2. A small and insignificant change to a program. Usually fixes one bug and generates several new ones. 3. vt. To change something in a small way. Bits, for example, are often twiddled. Twiddling a switch or knob implies much less sense of purpose than toggling or tweaking it; see {frobnicate}. To speak of twiddling a bit connotes aimlessness, and at best doesn't specify what you're doing to the bit; 'toggling a bit' has a more specific meaning (see {bit twiddling}, {toggle}).

:twilight zone: [IRC] n. Notionally, the area of cyberspace where {IRC} operators live. An {op} is said to have a "connection to the twilight zone". :twink: /twink/ [UCSC] n. Equivalent to {read-only user}. Also reported on the USENET group soc.motss; may derive from gay slang for a cute young thing with nothing upstairs (compare mainstream 'chick').

:two pi: quant. The number of years it takes to finish one's thesis. Occurs in stories in the following form: "He started on his thesis; 2 pi years later..."

:two-to-the-N: quant. An amount much larger than {N} but smaller than {infinity}. "I have 2-to-the-N things to do before I can go out for lunch" means you probably won't show up.

:twonkie: /twon'kee/ n. The software equivalent of a Twinkie (a variety of sugar-loaded junk food, or (in gay slang) the male equivalent of 'chick'); a useless 'feature' added to look sexy and placate a {marketroid} (compare {Saturday-night special}). This may also be related to "The Twonky", title menace of a classic SF short story by Lewis Padgett (Henry Kuttner and C. L. Moore), first published in the September 1942 'Astounding Science Fiction' and subsequently much anthologized.

= U = =====

:UBD: /U-B-D/ [abbreviation for 'User Brain Damage'] An abbreviation used to close out trouble reports obviously due to utter cluelessness on the user's part. Compare {pilot error}; oppose {PBD}; see also {brain-damaged}.

:UN*X: n. Used to refer to the UNIX operating system (a trademark of AT&T) in writing, but avoiding the need for the ugly {(TM)} typography. Also used to refer to any or all varieties of Unixoid operating systems. Ironically, lawyers now say (1990) that the requirement for the TM-postfix has no legal force, but the asterisk usage is entrenched anyhow. It has been suggested that there may be a psychological connection to practice in certain religions (especially Judaism) in which the name of the deity is never written out in full, e.g., 'YHWH' or 'G—d' is used. See also {glob}.

:undefined external reference: excl. [UNIX] A message from UNIX's linker. Used in speech to flag loose ends or dangling references in an argument or discussion.

:under the hood: prep. [hot-rodder talk] 1. Used to introduce the underlying implementation of a product (hardware, software, or idea). Implies that the implementation is not intuitively obvious from the appearance, but the speaker is about to enable the listener to {grok} it. "Let's now look under the hood to see how ...." 2. Can also imply that the implementation is much simpler than the appearance would indicate: "Under the hood, we are just fork/execing the shell." 3. Inside a chassis, as in "Under the hood, this baby has a 40MHz 68030!"

:undocumented feature: n. See {feature}.

:uninteresting: adj. 1. Said of a problem that, although {nontrivial}, can be solved simply by throwing sufficient resources at it. 2. Also said of problems for which a solution would neither advance the state of the art nor be fun to design and code.

Hackers regard uninteresting problems as intolerable wastes of time, to be solved (if at all) by lesser mortals. *Real* hackers (see {toolsmith}) generalize uninteresting problems enough to make them interesting and solve them —- thus solving the original problem as a special case (and, it must be admitted, occasionally turning a molehill into a mountain, or a mountain into a tectonic plate). See {WOMBAT}, {SMOP}; compare {toy problem}, oppose {interesting}.

:UNIX:: /yoo'niks/ [In the authors' words, "A weak pun on Multics"] n. (also 'Unix') An interactive time-sharing system originally invented in 1969 by Ken Thompson after Bell Labs left the Multics project, originally so he could play games on his scavenged PDP-7. Dennis Ritchie, the inventor of C, is considered a co-author of the system. The turning point in UNIX's history came when it was reimplemented almost entirely in C during 1972—1974, making it the first source-portable OS. UNIX subsequently underwent mutations and expansions at the hands of many different people, resulting in a uniquely flexible and developer-friendly environment. In 1991, UNIX is the most widely used multiuser general-purpose operating system in the world. Many people consider this the most important victory yet of hackerdom over industry opposition (but see {UNIX weenie} and {UNIX conspiracy} for an opposing point of view). See {Version 7}, {BSD}, {USG UNIX}.

:UNIX brain damage: n. Something that has to be done to break a network program (typically a mailer) on a non-UNIX system so that it will interoperate with UNIX systems. The hack may qualify as 'UNIX brain damage' if the program conforms to published standards and the UNIX program in question does not. UNIX brain damage happens because it is much easier for other (minority) systems to change their ways to match non-conforming behavior than it is to change all the hundreds of thousands of UNIX systems out there.

An example of UNIX brain damage is a {kluge} in a mail server to recognize bare line feed (the UNIX newline) as an equivalent form to the Internet standard newline, which is a carriage return followed by a line feed. Such things can make even a hardened {jock} weep.

:UNIX conspiracy: [ITS] n. According to a conspiracy theory long popular among {{ITS}} and {{TOPS-20}} fans, UNIX's growth is the result of a plot, hatched during the 1970s at Bell Labs, whose intent was to hobble AT&T's competitors by making them dependent upon a system whose future evolution was to be under AT&T's control. This would be accomplished by disseminating an operating system that is apparently inexpensive and easily portable, but also relatively unreliable and insecure (so as to require continuing upgrades from AT&T). This theory was lent a substantial impetus in 1984 by the paper referenced in the {back door} entry.

In this view, UNIX was designed to be one of the first computer viruses (see {virus}) —- but a virus spread to computers indirectly by people and market forces, rather than directly through disks and networks. Adherents of this 'UNIX virus' theory like to cite the fact that the well-known quotation "UNIX is snake oil" was uttered by DEC president Kenneth Olsen shortly before DEC began actively promoting its own family of UNIX workstations. (Olsen now claims to have been misquoted.)

:UNIX weenie: [ITS] n. 1. A derogatory play on 'UNIX wizard', common among hackers who use UNIX by necessity but would prefer alternatives. The implication is that although the person in question may consider mastery of UNIX arcana to be a wizardly skill, the only real skill involved is the ability to tolerate (and the bad taste to wallow in) the incoherence and needless complexity that is alleged to infest many UNIX programs. "This shell script tries to parse its arguments in 69 bletcherous ways. It must have been written by a real UNIX weenie." 2. A derogatory term for anyone who engages in uncritical praise of UNIX. Often appearing in the context "stupid UNIX weenie". See {Weenix}, {UNIX conspiracy}. See also {weenie}.

:unixism: n. A piece of code or a coding technique that depends on the protected multi-tasking environment with relatively low process-spawn overhead that exists on virtual-memory UNIX systems. Common {unixism}s include: gratuitous use of 'fork(2)'; the assumption that certain undocumented but well-known features of UNIX libraries such as 'stdio(3)' are supported elsewhere; reliance on {obscure} side-effects of system calls (use of 'sleep(2)' with a 0 argument to clue the scheduler that you're willing to give up your time-slice, for example); the assumption that freshly allocated memory is zeroed; and the assumption that fragmentation problems won't arise from never 'free()'ing memory. Compare {vaxocentrism}; see also {New Jersey}.

:unleaded: adj. Said of decaffeinated coffee, diet coke, and other imitation {programming fluid}s. "Do you want regular or unleaded?". Appears to be widespread among programmers associated with the oil industry in Texas (and probably elsewhere). Usage: silly, and probably unintelligable to the next generation of hackers.

:unroll: v. To repeat the body of a loop several times in succession. This optimization technique reduces the number of times the loop-termination test has to be executed. But it only works if the number of iterations desired is a multiple of the number of repetitions of the body. Something has to be done to take care of any leftover iterations —- such as {Duff's device}.

:unswizzle: v. See {swizzle}.

:unwind the stack: vi. 1. [techspeak] During the execution of a procedural language, one is said to 'unwind the stack' from a called procedure up to a caller when one discards the stack frame and any number of frames above it, popping back up to the level of the given caller. In C this is done with 'longjmp'/'setjmp', in LISP with 'throw/catch'. See also {smash the stack}. 2. People can unwind the stack as well, by quickly dealing with a bunch of problems: "Oh heck, let's do lunch. Just a second while I unwind my stack."

:unwind-protect: [MIT: from the name of a LISP operator] n. A task you must remember to perform before you leave a place or finish a project. "I have an unwind-protect to call my advisor."

:up: adj. 1. Working, in order. "The down escalator is up." Oppose {down}. 2. 'bring up': vt. To create a working version and start it. "They brought up a down system." 3. 'come up' vi. To become ready for production use.

:upload: /uhp'lohd/ v. 1. [techspeak] To transfer programs or data over a digital communications link from a smaller or peripheral 'client' system to a larger or central 'host' one. A transfer in the other direction is, of course, called a {download} (but see the note about ground-to-space comm under that entry). 2. [speculatively] To move the essential patterns and algorithms that make up one's mind from one's brain into a computer. Only those who are convinced that such patterns and algorithms capture the complete essence of the self view this prospect with gusto.

:upthread: adv. Earlier in the discussion (see {thread}), i.e., 'above'. "As Joe pointed out upthread, ..." See also {followup}.

:urchin: n. See {munchkin}.

:USENET: /yoos'net/ or /yooz'net/ [from 'Users' Network'] n. A distributed {bboard} (bulletin board) system supported mainly by UNIX machines. Originally implemented in 1979-1980 by Steve Bellovin, Jim Ellis, Tom Truscott, and Steve Daniel at Duke University, it has swiftly grown to become international in scope and is now probably the largest decentralized information utility in existence. As of early 1991, it hosts well over 700 {newsgroup}s and an average of 16 megabytes (the equivalent of several thousand paper pages) of new technical articles, news, discussion, chatter, and {flamage} every day.

:user: n. 1. Someone doing 'real work' with the computer, using it as a means rather than an end. Someone who pays to use a computer. See {real user}. 2. A programmer who will believe anything you tell him. One who asks silly questions. [GLS observes: This is slightly unfair. It is true that users ask questions (of necessity). Sometimes they are thoughtful or deep. Very often they are annoying or downright stupid, apparently because the user failed to think for two seconds or look in the documentation before bothering the maintainer.] See {luser}. 3. Someone who uses a program from the outside, however skillfully, without getting into the internals of the program. One who reports bugs instead of just going ahead and fixing them.

The general theory behind this term is that there are two classes of people who work with a program: there are implementors (hackers) and {luser}s. The users are looked down on by hackers to some extent because they don't understand the full ramifications of the system in all its glory. (The few users who do are known as 'real winners'.) The term is a relative one: a skilled hacker may be a user with respect to some program he himself does not hack. A LISP hacker might be one who maintains LISP or one who uses LISP (but with the skill of a hacker). A LISP user is one who uses LISP, whether skillfully or not. Thus there is some overlap between the two terms; the subtle distinctions must be resolved by context.

:user-friendly: adj. Programmer-hostile. Generally used by hackers in a critical tone, to describe systems that hold the user's hand so obsessively that they make it painful for the more experienced and knowledgeable to get any work done. See {menuitis}, {drool-proof paper}, {Macintrash}, {user-obsequious}.

:user-obsequious: adj. Emphatic form of {user-friendly}. Connotes a system so verbose, inflexible, and determinedly simple-minded that it is nearly unusable. "Design a system any fool can use and only a fool will want to use it." See {WIMP environment}, {Macintrash}.

:USG UNIX: /U-S-G yoo'niks/ n. Refers to AT&T UNIX commercial versions after {Version 7}, especially System III and System V releases 1, 2, and 3. So called because during most of the life-span of those versions AT&T's support crew was called the 'UNIX Support Group'. See {BSD}, {{UNIX}}.

:UTSL: // [UNIX] n. On-line acronym for 'Use the Source, Luke' (a pun on Obi-Wan Kenobi's "Use the Force, Luke!" in 'Star Wars') —- analogous to {RTFM} but more polite. This is a common way of suggesting that someone would be best off reading the source code that supports whatever feature is causing confusion, rather than making yet another futile pass through the manuals or broadcasting questions that haven't attracted {wizard}s to answer them. In theory, this is appropriately directed only at associates of some outfit with a UNIX source license; in practice, bootlegs of UNIX source code (made precisely for reference purposes) are so ubiquitous that one may utter this at almost anyone on the network without concern. In the near future (this written in 1991) source licenses may become even less important; after the recent release of the Mach 3.0 microkernel, given the continuing efforts of the {GNU} project, and with the 4.4BSD release on the horizon, complete free source code for UNIX-clone toolsets and kernels should soon be widely available.

:UUCPNET: n. The store-and-forward network consisting of all the world's connected UNIX machines (and others running some clone of the UUCP (UNIX-to-UNIX CoPy) software). Any machine reachable only via a {bang path} is on UUCPNET. See {network address}.

= V = =====

:vadding: /vad'ing/ [from VAD, a permutation of ADV (i.e., {ADVENT}), used to avoid a particular {admin}'s continual search-and-destroy sweeps for the game] n. A leisure-time activity of certain hackers involving the covert exploration of the 'secret' parts of large buildings —- basements, roofs, freight elevators, maintenance crawlways, steam tunnels, and the like. A few go so far as to learn locksmithing in order to synthesize vadding keys. The verb is 'to vad' (compare {phreaking}; see also {hack}, sense 9). This term dates from the late 1970s, before which such activity was simply called 'hacking'; the older usage is still prevalent at MIT.

The most extreme and dangerous form of vadding is 'elevator rodeo', a.k.a. 'elevator surfing', a sport played by wrasslin' down a thousand-pound elevator car with a 3-foot piece of string, and then exploiting this mastery in various stimulating ways (such as elevator hopping, shaft exploration, rat-racing, and the ever-popular drop experiments). Kids, don't try this at home! See also {hobbit} (sense 2).

:vanilla: [from the default flavor of ice cream in the U.S.] adj. Ordinary {flavor}, standard. When used of food, very often does not mean that the food is flavored with vanilla extract! For example, 'vanilla wonton soup' means ordinary wonton soup, as opposed to hot-and-sour wonton soup. Applied to hardware and software, as in "Vanilla Version 7 UNIX can't run on a vanilla 11/34." Also used to orthogonalize chip nomenclature; for instance, a 74V00 means what TI calls a 7400, as distinct from a 74LS00, etc. This word differs from {canonical} in that the latter means 'default', whereas vanilla simply means 'ordinary'. For example, when hackers go on a {great-wall}, hot-and-sour wonton soup is the {canonical} wonton soup to get (because that is what most of them usually order) even though it isn't the vanilla wonton soup.

:vannevar: /van'*-var/ n. A bogus technological prediction or a foredoomed engineering concept, esp. one that fails by implicitly assuming that technologies develop linearly, incrementally, and in isolation from one another when in fact the learning curve tends to be highly nonlinear, revolutions are common, and competition is the rule. The prototype was Vannevar Bush's prediction of 'electronic brains' the size of the Empire State Building with a Niagara-Falls-equivalent cooling system for their tubes and relays, made at a time when the semiconductor effect had already been demonstrated. Other famous vannevars have included magnetic-bubble memory, LISP machines, {videotex}, and a paper from the late 1970s that computed a purported ultimate limit on areal density for ICs that was in fact less than the routine densities of 5 years later.

:vaporware: /vay'pr-weir/ n. Products announced far in advance of any release (which may or may not actually take place).

:var: /veir/ or /var/ n. Short for 'variable'. Compare {arg}, {param}.

:VAX: /vaks/ n. 1. [from Virtual Address eXtension] The most successful minicomputer design in industry history, possibly excepting its immediate ancestor, the PDP-11. Between its release in 1978 and its eclipse by {killer micro}s after about 1986, the VAX was probably the hacker's favorite machine of them all, esp. after the 1982 release of 4.2 BSD UNIX (see {BSD}). Esp. noted for its large, assembler-programmer-friendly instruction set —- an asset that became a liability after the RISC revolution. 2. A major brand of vacuum cleaner in Britain. Cited here because its alleged sales pitch, "Nothing sucks like a VAX!" became a sort of battle-cry of RISC partisans. It is sometimes claimed that this slogan was *not* actually used by the Vax vacuum-cleaner people, but was actually that of a rival brand called Electrolux (as in "Nothing sucks like..."); your editors have not yet been able to verify either version of the legend. It is also claimed that DEC actually entered a cross-licensing deal with the vacuum-Vax people that allowed them to market VAX computers in the U.K. in return for not challenging the vacuum cleaner trademark in the U.S.

:VAXectomy: /vak-sek't*-mee/ [by analogy with 'vasectomy'] n. A VAX removal. DEC's Microvaxen, especially, are much slower than newer RISC-based workstations such as the SPARC. Thus, if one knows one has a replacement coming, VAX removal can be cause for celebration.

:VAXen: /vak'sn/ [from 'oxen', perhaps influenced by 'vixen'] n. (alt. 'vaxen') The plural canonically used among hackers for the DEC VAX computers. "Our installation has four PDP-10s and twenty vaxen." See {boxen}.

:vaxherd: n. /vaks'herd/ [from 'oxherd'] A VAX operator.

:vaxism: /vak'sizm/ n. A piece of code that exhibits {vaxocentrism} in critical areas. Compare {PC-ism}, {unixism}.

:vaxocentrism: /vak'soh-sen'trizm/ [analogy with 'ethnocentrism'] n. A notional disease said to afflict C programmers who persist in coding according to certain assumptions that are valid (esp. under UNIX) on {VAXen} but false elsewhere. Among these are:

1. The assumption that dereferencing a null pointer is safe because it is all bits 0, and location 0 is readable and 0. Problem: this may instead cause an illegal-address trap on non-VAXen, and even on VAXen under OSes other than BSD UNIX. Usually this is an implicit assumption of sloppy code (forgetting to check the pointer before using it), rather than deliberate exploitation of a misfeature.)

2. The assumption that characters are signed.

3. The assumption that a pointer to any one type can freely be cast into a pointer to any other type. A stronger form of this is the assumption that all pointers are the same size and format, which means you don't have to worry about getting the types correct in calls. Problem: this fails on word-oriented machines or others with multiple pointer formats.

4. The assumption that the parameters of a routine are stored in memory, contiguously, and in strictly ascending or descending order. Problem: this fails on many RISC architectures.

5. The assumption that pointer and integer types are the same size, and that pointers can be stuffed into integer variables (and vice-versa) and drawn back out without being truncated or mangled. Problem: this fails on segmented architectures or word-oriented machines with funny pointer formats.

6. The assumption that a data type of any size may begin at any byte address in memory (for example, that you can freely construct and dereference a pointer to a word- or greater-sized object at an odd char address). Problem: this fails on many (esp. RISC) architectures better optimized for {HLL} execution speed, and can cause an illegal address fault or bus error.

7. The (related) assumption that there is no padding at the end of types and that in an array you can thus step right from the last byte of a previous component to the first byte of the next one. This is not only machine- but compiler-dependent.

8. The assumption that memory address space is globally flat and that the array reference 'foo[-1]' is necessarily valid. Problem: this fails at 0, or other places on segment-addressed machines like Intel chips (yes, segmentation is universally considered a {brain-damaged} way to design machines (see {moby}), but that is a separate issue).

9. The assumption that objects can be arbitrarily large with no special considerations. Problem: this fails on segmented architectures and under non-virtual-addressing environments.

10. The assumption that the stack can be as large as memory. Problem: this fails on segmented architectures or almost anything else without virtual addressing and a paged stack.

11. The assumption that bits and addressable units within an object are ordered in the same way and that this order is a constant of nature. Problem: this fails on {big-endian} machines.

12. The assumption that it is meaningful to compare pointers to different objects not located within the same array, or to objects of different types. Problem: the former fails on segmented architectures, the latter on word-oriented machines or others with multiple pointer formats.

13. The assumption that an 'int' is 32 bits, or (nearly equivalently) the assumption that 'sizeof(int) == sizeof(long)'. Problem: this fails on PDP-11s, 286-based systems and even on 386 and 68000 systems under some compilers.

14. The assumption that 'argv[]' is writable. Problem: this fails in many embedded-systems C environments and even under a few flavors of UNIX.

Note that a programmer can validly be accused of vaxocentrism even if he or she has never seen a VAX. Some of these assumptions (esp. 2—5) were valid on the PDP-11, the original C machine, and became endemic years before the VAX. The terms 'vaxocentricity' and 'all-the-world's-a-VAX syndrome' have been used synonymously.

:vdiff: /vee'dif/ v.,n. Visual diff. The operation of finding differences between two files by {eyeball search}. The term 'optical diff' has also been reported, and is sometimes more specifically used for the act of superimposing two nearly identical printouts on one another and holding them up to a light to spot differences. Though this method is poor for detecting omissions in the 'rear' file, it can also be used with printouts of graphics, a claim few if any diff programs can make. See {diff}.

:veeblefester: /vee'b*l-fes'tr/ [from the "Born Loser" comix via Commodore; prob. originally from 'Mad' Magazine's 'Veeblefeetzer' parodies ca. 1960] n. Any obnoxious person engaged in the (alleged) professions of marketing or management. Antonym of {hacker}. Compare {suit}, {marketroid}.

:Venus flytrap: [after the insect-eating plant] n. See {firewall machine}.

:verbage: /ver'b*j/ n. A deliberate misspelling and mispronunciation of {verbiage} that assimilates it to the word 'garbage'. Compare {content-free}. More pejorative than 'verbiage'.

:verbiage: n. When the context involves a software or hardware system, this refers to {{documentation}}. This term borrows the connotations of mainstream 'verbiage' to suggest that the documentation is of marginal utility and that the motives behind its production have little to do with the ostensible subject.

:Version 7: alt. V7 /vee' se'vn/ n. The 1978 unsupported release of {{UNIX}} ancestral to all current commercial versions. Before the release of the POSIX/SVID standards, V7's features were often treated as a UNIX portability baseline. See {BSD}, {USG UNIX}, {{UNIX}}. Some old-timers impatient with commercialization and kernel bloat still maintain that V7 was the Last True UNIX.

:vgrep: /vee'grep/ v.,n. Visual grep. The operation of finding patterns in a file optically rather than digitally (also called an 'optical grep'). See {grep}; compare {vdiff}.

:vi: /V-I/, *not* /vi:/ and *never* /siks/ [from 'Visual Interface'] n. A screen editor crufted together by Bill Joy for an early {BSD} release. Became the de facto standard UNIX editor and a nearly undisputed hacker favorite outside of MIT until the rise of {EMACS} after about 1984. Tends to frustrate new users no end, as it will neither take commands while expecting input text nor vice versa, and the default setup provides no indication of which mode one is in (one correspondent accordingly reports that he has often heard the editor's name pronounced /vi:l/). Nevertheless it is still widely used (about half the respondents in a 1991 USENET poll preferred it), and even EMACS fans often resort to it as a mail editor and for small editing jobs (mainly because it starts up faster than the bulkier versions of EMACS). See {holy wars}.

:videotex: n. obs. An electronic service offering people the privilege of paying to read the weather on their television screens instead of having somebody read it to them for free while they brush their teeth. The idea bombed everywhere it wasn't government-subsidized, because by the time videotex was practical the installed base of personal computers could hook up to timesharing services and do the things for which videotex might have been worthwhile better and cheaper. Videotex planners badly overestimated both the appeal of getting information from a computer and the cost of local intelligence at the user's end. Like the {gorilla arm} effect, this has been a cautionary tale to hackers ever since. See also {vannevar}.

:virgin: adj. Unused; pristine; in a known initial state. "Let's bring up a virgin system and see if it crashes again." (Esp. useful after contracting a {virus} through {SEX}.) Also, by extension, buffers and the like within a program that have not yet been used.

:virtual: [via the technical term 'virtual memory', prob. from the term 'virtual image' in optics] adj. 1. Common alternative to {logical}; often used to refer to the artificial objects created by a computer system to help the system control access to shared resources. 2. Simulated; performing the functions of something that isn't really there. An imaginative child's doll may be a virtual playmate. Oppose {real}.

:virtual Friday: n. The last day before an extended weekend, if that day is not a 'real' Friday. For example, the U.S. holiday Thanksgiving is always on a Thursday. The next day is often also a holiday or taken as an extra day off, in which case Wednesday of that week is a virtual Friday (and Thursday is a virtual Saturday, as is Friday). There are also 'virtual Mondays' that are actually Tuesdays, after the three-day weekends associated with many national holidays in the U.S.

:virtual reality: n. 1. Computer simulations that use 3-D graphics and devices such as the Dataglove to allow the user to interact with the simulation. See {cyberspace}. 2. A form of network interaction incorporating aspects of role-playing games, interactive theater, improvisational comedy, and 'true confessions' magazines. In a virtual reality forum (such as USENET's alt.callahans newsgroup or the {MUD} experiments on Internet), interaction between the participants is written like a shared novel complete with scenery, 'foreground characters' that may be personae utterly unlike the people who write them, and common 'background characters' manipulable by all parties. The one iron law is that you may not write irreversible changes to a character without the consent of the person who 'owns' it. Otherwise anything goes. See {bamf}, {cyberspace}.

:virus: [from the obvious analogy with biological viruses, via SF] n. A cracker program that searches out other programs and 'infects' them by embedding a copy of itself in them, so that they become {Trojan Horse}s. When these programs are executed, the embedded virus is executed too, thus propagating the 'infection'. This normally happens invisibly to the user. Unlike a {worm}, a virus cannot infect other computers without assistance. It is propagated by vectors such as humans trading programs with their friends (see {SEX}). The virus may do nothing but propagate itself and then allow the program to run normally. Usually, however, after propagating silently for a while, it starts doing things like writing cute messages on the terminal or playing strange tricks with your display (some viruses include nice {display hack}s). Many nasty viruses, written by particularly perversely minded {cracker}s, do irreversible damage, like nuking all the user's files.

In the 1990s, viruses have become a serious problem, especially among IBM PC and Macintosh users (the lack of security on these machines enables viruses to spread easily, even infecting the operating system). The production of special anti-virus software has become an industry, and a number of exaggerated media reports have caused outbreaks of near hysteria among users; many {luser}s tend to blame *everything* that doesn't work as they had expected on virus attacks. Accordingly, this sense of 'virus' has passed not only into techspeak but into also popular usage (where it is often incorrectly used to denote a {worm} or even a {Trojan horse}). Compare {back door}; see also {UNIX conspiracy}.

:visionary: n. 1. One who hacks vision, in the sense of an Artificial Intelligence researcher working on the problem of getting computers to 'see' things using TV cameras. (There isn't any problem in sending information from a TV camera to a computer. The problem is, how can the computer be programmed to make use of the camera information? See {SMOP}, {AI-complete}.) 2. [IBM] One who reads the outside literature. At IBM, apparently, such a penchant is viewed with awe and wonder.

:VMS: /V-M-S/ n. DEC's proprietary operating system for its VAX minicomputer; one of the seven or so environments that loom largest in hacker folklore. Many UNIX fans generously concede that VMS would probably be the hacker's favorite commercial OS if UNIX didn't exist; though true, this makes VMS fans furious. One major hacker gripe with VMS concerns its slowness —- thus the following limerick:

There once was a system called VMS Of cycles by no means abstemious. It's chock-full of hacks And runs on a VAX And makes my poor stomach all squeamious. —- The Great Quux

See also {VAX}, {{TOPS-10}}, {{TOPS-20}}, {{UNIX}}, {runic}.

:voice: vt. To phone someone, as opposed to emailing them or connecting in {talk mode}. "I'm busy now; I'll voice you later."

:voice-net: n. Hackish way of referring to the telephone system, analogizing it to a digital network. USENET {sig block}s not uncommonly include the sender's phone next to a "Voice:" or "Voice-Net:" header; common variants of this are "Voicenet" and "V-Net". Compare {paper-net}, {snail-mail}.

:voodoo programming: [from George Bush's "voodoo economics"] n. The use by guess or cookbook of an {obscure} or {hairy} system, feature, or algorithm that one does not truly understand. The implication is that the technique may not work, and if it doesn't, one will never know why. Almost synonymous with {black magic}, except that black magic typically isn't documented and *nobody* understands it. Compare {magic}, {deep magic}, {heavy wizardry}, {rain dance}, {cargo cult programming}, {wave a dead chicken}.

:VR: // [MUD] n. On-line abbrev for {virtual reality}, as opposed to {RL}.

:Vulcan nerve pinch: n. [from the old "Star Trek" TV series via Commodore Amiga hackers] The keyboard combination that forces a soft-boot or jump to ROM monitor (on machines that support such a feature). On many micros this is Ctrl-Alt-Del; on Suns, L1-A; on some Macintoshes, it is -! Also called {three-finger salute}. Compare {quadruple bucky}.

:vulture capitalist: n. Pejorative hackerism for 'venture capitalist', deriving from the common practice of pushing contracts that deprive inventors of control over their own innovations and most of the money they ought to have made from them.

= W = =====

:wabbit: /wab'it/ [almost certainly from Elmer Fudd's immortal line "You wascawwy wabbit!"] n. 1. A legendary early hack reported on a System/360 at RPI and elsewhere around 1978; this may have descended (if only by inspiration) from hack called RABBITS reported from 1969 on a Burroughs 55000 at the University of Washington Computer Center. The program would make two copies of itself every time it was run, eventually crashing the system. 2. By extension, any hack that includes infinite self-replication but is not a {virus} or {worm}. See {fork bomb}, see also {cookie monster}.

:WAITS:: /wayts/ n. The mutant cousin of {{TOPS-10}} used on a handful of systems at {{SAIL}} up to 1990. There was never an 'official' expansion of WAITS (the name itself having been arrived at by a rather sideways process), but it was frequently glossed as 'West-coast Alternative to ITS'. Though WAITS was less visible than ITS, there was frequent exchange of people and ideas between the two communities, and innovations pioneered at WAITS exerted enormous indirect influence. The early screen modes of {EMACS}, for example, were directly inspired by WAITS's 'E' editor —- one of a family of editors that were the first to do 'real-time editing', in which the editing commands were invisible and where one typed text at the point of insertion/overwriting. The modern style of multi-region windowing is said to have originated there, and WAITS alumni at XEROX PARC and elsewhere played major roles in the developments that led to the XEROX Star, the Macintosh, and the Sun workstations. {Bucky bits} were also invented there —- thus, the ALT key on every IBM PC is a WAITS legacy. One notable WAITS feature seldom duplicated elsewhere was a news-wire interface that allowed WAITS hackers to read, store, and filter AP and UPI dispatches from their terminals; the system also featured a still-unusual level of support for what is now called 'multimedia' computing, allowing analog audio and video signals to be switched to programming terminals.

:waldo: /wol'doh/ [From Robert A. Heinlein's story "Waldo"] 1. A mechanical agent, such as a gripper arm, controlled by a human limb. When these were developed for the nuclear industry in the mid-1940s they were named after the invention described by Heinlein in the story, which he wrote in 1942. Now known by the more generic term 'telefactoring', this technology is of intense interest to NASA for tasks like space station maintenance. 2. At Harvard (particularly by Tom Cheatham and students), this is used instead of {foobar} as a metasyntactic variable and general nonsense word. See {foo}, {bar}, {foobar}, {quux}.

:walk: n.,vt. Traversal of a data structure, especially an array or linked-list data structure in {core}. See also {codewalker}, {silly walk}, {clobber}.

:walk off the end of: vt. To run past the end of an array, list, or medium after stepping through it —- a good way to land in trouble. Often the result of an {off-by-one error}. Compare {clobber}, {roach}, {smash the stack}.

:walking drives: n. An occasional failure mode of magnetic-disk drives back in the days when they were huge, clunky {washing machine}s. Those old {dinosaur} parts carried terrific angular momentum; the combination of a misaligned spindle or worn bearings and stick-slip interactions with the floor could cause them to 'walk' across a room, lurching alternate corners forward a couple of millimeters at a time. There is a legend about a drive that walked over to the only door to the computer room and jammed it shut; the staff had to cut a hole in the wall in order to get at it! Walking could also be induced by certain patterns of drive access (a fast seek across the whole width of the disk, followed by a slow seek in the other direction). Some bands of old-time hackers figured out how to induce disk-accessing patterns that would do this to particular drive models and held disk-drive races.

:wall: [WPI] interj. 1. An indication of confusion, usually spoken with a quizzical tone: "Wall??" 2. A request for further explication. Compare {octal forty}. 3. [UNIX] v. To send a message to everyone currently logged in, esp. with the wall(8) utility.

It is said that sense 1 came from the idiom 'like talking to a blank wall'. It was originally used in situations where, after you had carefully answered a question, the questioner stared at you blankly, clearly having understood nothing that was explained. You would then throw out a "Hello, wall?" to elicit some sort of response from the questioner. Later, confused questioners began voicing "Wall?" themselves.

:wall follower: n. A person or algorithm that compensates for lack of sophistication or native stupidity by efficiently following some simple procedure shown to have been effective in the past. Used of an algorithm, this is not necessarily pejorative; it recalls 'Harvey Wallbanger', the winning robot in an early AI contest (named, of course, after the cocktail). Harvey successfully solved mazes by keeping a 'finger' on one wall and running till it came out the other end. This was inelegant, but it was mathematically guaranteed to work on simply-connected mazes —- and, in fact, Harvey outperformed more sophisticated robots that tried to 'learn' each maze by building an internal representation of it. Used of humans, the term *is* pejorative and implies an uncreative, bureaucratic, by-the-book mentality. See also {code grinder}, {droid}.

:wall time: n. (also 'wall clock time') 1. 'Real world' time (what the clock on the wall shows), as opposed to the system clock's idea of time. 2. The real running time of a program, as opposed to the number of {clocks} required to execute it (on a timesharing system these will differ, as no one program gets all the {clocks}, and on multiprocessor systems with good thread support one may get more processor clocks than real-time clocks).

:wallpaper: n. 1. A file containing a listing (e.g., assembly listing) or a transcript, esp. a file containing a transcript of all or part of a login session. (The idea was that the paper for such listings was essentially good only for wallpaper, as evidenced at Stanford, where it was used to cover windows.) Now rare, esp. since other systems have developed other terms for it (e.g., PHOTO on TWENEX). However, the UNIX world doesn't have an equivalent term, so perhaps {wallpaper} will take hold there. The term probably originated on ITS, where the commands to begin and end transcript files were ':WALBEG' and ':WALEND', with default file 'WALL PAPER' (the space was a path delimiter). 2. The background pattern used on graphical workstations (this is techspeak under the 'Windows' graphical user interface to MS-DOS). 3. 'wallpaper file' n. The file that contains the wallpaper information before it is actually printed on paper. (Even if you don't intend ever to produce a real paper copy of the file, it is still called a wallpaper file.)

:wango: /wang'goh/ n. Random bit-level {grovel}ling going on in a system during some unspecified operation. Often used in combination with {mumble}. For example: "You start with the '.o' file, run it through this postprocessor that does mumble-wango —- and it comes out a snazzy object-oriented executable."

:wank: /wangk/ [Columbia University: prob. by mutation from Commonwealth slang v. 'wank', to masturbate] n.,v. Used much as {hack} is elsewhere, as a noun denoting a clever technique or person or the result of such cleverness. May describe (negatively) the act of hacking for hacking's sake ("Quit wanking, let's go get supper!") or (more positively) a {wizard}. Adj. 'wanky' describes something particularly clever (a person, program, or algorithm). Conversations can also get wanky when there are too many wanks involved. This excess wankiness is signalled by an overload of the 'wankometer' (compare {bogometer}). When the wankometer overloads, the conversation's subject must be changed, or all non-wanks will leave. Compare 'neep-neeping' (under {neep-neep}). Usage: U.S. only. In Britain and the Commonwealth this word is *extremely* rude and is best avoided unless one intends to give offense.

:wannabee: /won'*-bee/ (also, more plausibly, spelled 'wannabe') [from a term recently used to describe Madonna fans who dress, talk, and act like their idol; prob. originally from biker slang] n. A would-be {hacker}. The connotations of this term differ sharply depending on the age and exposure of the subject. Used of a person who is in or might be entering {larval stage}, it is semi-approving; such wannabees can be annoying but most hackers remember that they, too, were once such creatures. When used of any professional programmer, CS academic, writer, or {suit}, it is derogatory, implying that said person is trying to cuddle up to the hacker mystique but doesn't, fundamentally, have a prayer of understanding what it is all about. Overuse of terms from this lexicon is often an indication of the {wannabee} nature. Compare {newbie}.

Historical note: The wannabee phenomenon has a slightly different flavor now (1991) than it did ten or fifteen years ago. When the people who are now hackerdom's tribal elders were in {larval stage}, the process of becoming a hacker was largely unconscious and unaffected by models known in popular culture —- communities formed spontaneously around people who, *as individuals*, felt irresistibly drawn to do hackerly things, and what wannabees experienced was a fairly pure, skill-focused desire to become similarly wizardly. Those days of innocence are gone forever; society's adaptation to the advent of the microcomputer after 1980 included the elevation of the hacker as a new kind of folk hero, and the result is that some people semi-consciously set out to *be hackers* and borrow hackish prestige by fitting the popular image of hackers. Fortunately, to do this really well, one has to actually become a wizard. Nevertheless, old-time hackers tend to share a poorly articulated disquiet about the change; among other things, it gives them mixed feelings about the effects of public compendia of lore like this one.

:warlording: [from the USENET group alt.fan.warlord] v. The act of excoriating a bloated, ugly, or derivative {sig block}. Common grounds for warlording include the presence of a signature rendered in a {BUAF}, over-used or cliched {sig quote}s, ugly {ASCII art}, or simply excessive size. The original 'Warlord' was a {BIFF}-like {newbie} c.1991 who featured in his sig a particularly large and obnoxious ASCII graphic resembling the sword of Conan the Barbarian in the 1981 John Milius movie; the group name alt.fan.warlord was sarcasm, and the characteristic mode of warlording is devastatingly sarcastic praise.

:warm boot: n. See {boot}.

:wart: n. A small, {crock}y {feature} that sticks out of an otherwise {clean} design. Something conspicuous for localized ugliness, especially a special-case exception to a general rule. For example, in some versions of 'csh(1)', single quotes literalize every character inside them except '!'. In ANSI C, the '??' syntax used obtaining ASCII characters in a foreign environment is a wart. See also {miswart}.

:washing machine: n. Old-style 14-inch hard disks in floor-standing cabinets. So called because of the size of the cabinet and the 'top-loading' access to the media packs —- and, of course, they were always set on 'spin cycle'. The washing-machine idiom transcends language barriers; it is even used in Russian hacker jargon. See also {walking drives}. The thick channel cables connecting these were called 'bit hoses' (see {hose}).

:water MIPS: n. (see {MIPS}, sense 2) Large, water-cooled machines of either today's ECL-supercomputer flavor or yesterday's traditional {mainframe} type.

:wave a dead chicken: v. To perform a ritual in the direction of crashed software or hardware that one believes to be futile but is nevertheless necessary so that others are satisfied that an appropriate degree of effort has been expended. "I'll wave a dead chicken over the source code, but I really think we've run into an OS bug." Compare {voodoo programming}, {rain dance}.

:weasel: n. [Cambridge] A na"ive user, one who deliberately or accidentally does things that are stupid or ill-advised. Roughly synonymous with {loser}.

:wedged: [from a common description of recto-cranial inversion] adj. 1. To be stuck, incapable of proceeding without help. This is different from having crashed. If the system has crashed, then it has become totally non-functioning. If the system is wedged, it is trying to do something but cannot make progress; it may be capable of doing a few things, but not be fully operational. For example, a process may become wedged if it {deadlock}s with another (but not all instances of wedging are deadlocks). See also {gronk}, {locked up}, {hosed}. Describes a {deadlock}ed condition. 2. Often refers to humans suffering misconceptions. "He's totally wedged —- he's convinced that he can levitate through meditation." 3. [UNIX] Specifically used to describe the state of a TTY left in a losing state by abort of a screen-oriented program or one that has messed with the line discipline in some obscure way.

:wedgie: [Fairchild] n. A bug. Prob. related to {wedged}.

:wedgitude: /wedj'i-t[y]ood/ n. The quality or state of being {wedged}.

:weeble: /weeb'l/ [Cambridge] interj. Used to denote frustration, usually at amazing stupidity. "I stuck the disk in upside down." "Weeble...." Compare {gurfle}.

:weeds: n. 1. Refers to development projects or algorithms that have no possible relevance or practical application. Comes from 'off in the weeds'. Used in phrases like "lexical analysis for microcode is serious weeds...." 2. At CDC/ETA before its demise, the phrase 'go off in the weeds' was equivalent to IBM's {branch to Fishkill} and mainstream hackerdom's {jump off into never-never land}.

:weenie: n. 1. [on BBSes] Any of a species of luser resembling a less amusing version of {BIFF} that infests many {BBS} systems. The typical weenie is a teenage boy with poor social skills travelling under a grandiose {handle} derived from fantasy or heavy-metal rock lyrics. Among sysops, 'the weenie problem' refers to the marginally literate and profanity-laden {flamage} weenies tend to spew all over a newly-discovered BBS. Compare {spod}, {computer geek}, {terminal junkie}. 2. [Among hackers] When used with a qualifier (for example, as in {UNIX weenie}, VMS weenie, IBM weenie) this can be either an insult or a term of praise, depending on context, tone of voice, and whether or not it is applied by a person who considers him or herself to be the same sort of weenie. Implies that the weenie has put a major investment of time, effort, and concentration into the area indicated; whether this is positive or negative depends on the hearer's judgment of how the speaker feels about that area. See also {bigot}. 3. The semicolon character, ';' (ASCII 0111011).

:Weenix: /wee'niks/ [ITS] n. A derogatory term for {{UNIX}}, derived from {UNIX weenie}. According to one noted ex-ITSer, it is "the operating system preferred by Unix Weenies: typified by poor modularity, poor reliability, hard file deletion, no file version numbers, case sensitivity everywhere, and users who believe that these are all advantages". Some ITS fans behave as though they believe UNIX stole a future that rightfully belonged to them. See {{ITS}}, sense 2.

:well-behaved: adj. 1. [primarily {{MS-DOS}}] Said of software conforming to system interface guidelines and standards. Well-behaved software uses the operating system to do chores such as keyboard input, allocating memory and drawing graphics. Oppose {ill-behaved}. 2. Software that does its job quietly and without counterintuitive effects. Esp. said of software having an interface spec sufficiently simple and well-defined that it can be used as a {tool} by other software. See {cat}.

:well-connected: adj. Said of a computer installation, this means that it has reliable email links with the network and/or that it relays a large fraction of available {USENET} newsgroups. 'Well-known' can be almost synonymous, but also implies that the site's name is familiar to many (due perhaps to an archive service or active USENET users).

:wetware: /wet'weir/ [prob. from the novels of Rudy Rucker] n. 1. The human nervous system, as opposed to computer hardware or software. "Wetware has 7 plus or minus 2 temporary registers." 2. Human beings (programmers, operators, administrators) attached to a computer system, as opposed to the system's hardware or software. See {liveware}, {meatware}.

:whack: v. According to arch-hacker James Gosling, to "...modify a program with no idea whatsoever how it works." (See {whacker}.) It is actually possible to do this in nontrivial circumstances if the change is small and well-defined and you are very good at {glark}ing things from context. As a trivial example, it is relatively easy to change all 'stderr' writes to 'stdout' writes in a piece of C filter code which remains otherwise mysterious.

:whacker: [University of Maryland: from {hacker}] n. 1. A person, similar to a {hacker}, who enjoys exploring the details of programmable systems and how to stretch their capabilities. Whereas a hacker tends to produce great hacks, a whacker only ends up whacking the system or program in question. Whackers are often quite egotistical and eager to claim {wizard} status, regardless of the views of their peers. 2. A person who is good at programming quickly, though rather poorly and ineptly.

:whales: n. See {like kicking dead whales down the beach}.

:whalesong: n. The peculiar clicking and whooshing sounds made by a PEP modem such as the Telebit Trailblazer as it tries to synchronize with another PEP modem for their special high-speed mode. This sound isn't anything like the normal two-tone handshake between conventional modems and is instantly recognizable to anyone who has heard it more than once. It sounds, in fact, very much like whale songs. This noise is also called "the moose call" or "moose tones".

:What's a spline?: [XEROX PARC] This phrase expands to: "You have just used a term that I've heard for a year and a half, and I feel I should know, but don't. My curiosity has finally overcome my guilt." The PARC lexicon adds "Moral: don't hesitate to ask questions, even if they seem obvious."

:wheel: [from slang 'big wheel' for a powerful person] n. A person who has an active {wheel bit}. "We need to find a wheel to unwedge the hung tape drives." (see {wedged}, sense 1.)

:wheel bit: n. A privilege bit that allows the possessor to perform some restricted operation on a timesharing system, such as read or write any file on the system regardless of protections, change or look at any address in the running monitor, crash or reload the system, and kill or create jobs and user accounts. The term was invented on the TENEX operating system, and carried over to TOPS-20, XEROX-IFS, and others. The state of being in a privileged logon is sometimes called 'wheel mode'. This term entered the UNIX culture from TWENEX in the mid-1980s and has been gaining popularity there (esp. at university sites). See also {root}.

:wheel wars: [Stanford University] A period in {larval stage} during which student hackers hassle each other by attempting to log each other out of the system, delete each other's files, and otherwise wreak havoc, usually at the expense of the lesser users.

:White Book: n. 1. Syn. {K&R}. 2. Adobe's fourth book in the PostScript series, describing the previously-secret format of Type 1 fonts; 'Adobe Type 1 Font Format, version 1.1', (Addison-Wesley, 1990, ISBN 0-201-57044-0). See also {Red Book}, {Green Book}, {Blue Book}.

:whizzy: [Sun] adj. (alt. 'wizzy') Describes a {cuspy} program; one that is feature-rich and well presented.

:WIBNI: // [Bell Labs: Wouldn't It Be Nice If] n. What most requirements documents and specifications consist entirely of. Compare {IWBNI}.

:widget: n. 1. A meta-thing. Used to stand for a real object in didactic examples (especially database tutorials). Legend has it that the original widgets were holders for buggy whips. "But suppose the parts list for a widget has 52 entries...." 2. [poss. evoking 'window gadget'] A user interface object in {X} graphical user interfaces.

:wiggles: n. [scientific computation] In solving partial differential equations by finite difference and similar methods, wiggles are sawtooth (up-down-up-down) oscillations at the shortest wavelength representable on the grid. If an algorithm is unstable, this is often the most unstable waveform, so it grows to dominate the solution. Alternatively, stable (though inaccurate) wiggles can be generated near a discontinuity by a Gibbs phenomenon.

:WIMP environment: n. [acronymic from 'Window, Icon, Menu, Pointing device (or Pull-down menu)'] A graphical-user-interface-based environment such as {X} or the Macintosh interface, as described by a hacker who prefers command-line interfaces for their superior flexibility and extensibility. See {menuitis}, {user-obsequious}.

:win: [MIT] 1. vi. To succeed. A program wins if no unexpected conditions arise, or (especially) if it sufficiently {robust} to take exceptions in stride. 2. n. Success, or a specific instance thereof. A pleasing outcome. A {feature}. Emphatic forms: 'moby win', 'super win', 'hyper-win' (often used interjectively as a reply). For some reason 'suitable win' is also common at MIT, usually in reference to a satisfactory solution to a problem. Oppose {lose}; see also {big win}, which isn't quite just an intensification of 'win'.

:win big: vi. To experience serendipity. "I went shopping and won big; there was a 2-for-1 sale." See {big win}.

:win win: interj. Expresses pleasure at a {win}.

:Winchester:: n. Informal generic term for 'floating-head' magnetic-disk drives in which the read-write head planes over the disk surface on an air cushion. The name arose because the original 1973 engineering prototype for what later became the IBM 3340 featured two 30-megabyte volumes; 30—30 became 'Winchester' when somebody noticed the similarity to the common term for a famous Winchester rifle (in the latter, the first 30 referred to caliber and the second to the grain weight of the charge).

:winged comments: n. Comments set on the same line as code, as opposed to {boxed comments}. In C, for example:

d = sqrt(x*x + y*y); /* distance from origin */

Generally these refer only to the action(s) taken on that line.

:winkey: n. (alt. 'winkey face') See {emoticon}.

:winnage: /win'*j/ n. The situation when a lossage is corrected, or when something is winning.

:winner: 1. n. An unexpectedly good situation, program, programmer, or person. "So it turned out I could use a {lexer} generator instead of hand-coding my own pattern recognizer. What a win!" 2. 'real winner': Often sarcastic, but also used as high praise (see also the note under {user}). "He's a real winner —- never reports a bug till he can duplicate it and send in an example."

:winnitude: /win'*-t[y]ood/ n. The quality of winning (as opposed to {winnage}, which is the result of winning). "Guess what? They tweaked the microcode and now the LISP interpreter runs twice as fast as it used to." "That's really great! Boy, what winnitude!" "Yup. I'll probably get a half-hour's winnage on the next run of my program." Perhaps curiously, the obvious antonym 'lossitude' is rare.

:wired: n. See {hardwired}.

:wirehead: /wi:r'hed/ n. [prob. from SF slang for an electrical-brain-stimulation addict] 1. A hardware hacker, especially one who concentrates on communications hardware. 2. An expert in local-area networks. A wirehead can be a network software wizard too, but will always have the ability to deal with network hardware, down to the smallest component. Wireheads are known for their ability to lash up an Ethernet terminator from spare resistors, for example.

:wirewater: n. Syn. {programming fluid}. This melds the mainstream slang adjective 'wired' (stimulated, up, hyperactive) with 'firewater'.

:wish list: n. A list of desired features or bug fixes that probably won't get done for a long time, usually because the person responsible for the code is too busy or can't think of a clean way to do it. "OK, I'll add automatic filename completion to the wish list for the new interface." Compare {tick-list features}.

:within delta of: adj. See {delta}.

:within epsilon of: adj. See {epsilon}.

:wizard: n. 1. A person who knows how a complex piece of software or hardware works (that is, who {grok}s it); esp. someone who can find and fix bugs quickly in an emergency. Someone is a {hacker} if he or she has general hacking ability, but is a wizard with respect to something only if he or she has specific detailed knowledge of that thing. A good hacker could become a wizard for something given the time to study it. 2. A person who is permitted to do things forbidden to ordinary people; one who has {wheel} privileges on a system. 3. A UNIX expert, esp. a UNIX systems programmer. This usage is well enough established that 'UNIX Wizard' is a recognized job title at some corporations and to most headhunters. See {guru}, {lord high fixer}. See also {deep magic}, {heavy wizardry}, {incantation}, {magic}, {mutter}, {rain dance}, {voodoo programming}, {wave a dead chicken}.

:Wizard Book: n. Hal Abelson and Jerry Sussman's 'Structure and Interpretation of Computer Programs' (MIT Press, 1984; ISBN 0-262-01077-1, an excellent computer science text used in introductory courses at MIT. So called because of the wizard on the jacket. One of the {bible}s of the LISP/Scheme world. Also, less commonly, known as the {Purple Book}.

:wizard mode: [from {rogue}] n. A special access mode of a program or system, usually passworded, that permits some users godlike privileges. Generally not used for operating systems themselves ('root mode' or 'wheel mode' would be used instead).

:wizardly: adj. Pertaining to wizards. A wizardly {feature} is one that only a wizard could understand or use properly.

:womb box: n. 1. [TMRC] Storage space for equipment. 2. [proposed] A variety of hard-shell equipment case with heavy interior padding and/or shaped carrier cutouts in a foam-rubber matrix; mundanely called a 'flight case'. Used for delicate test equipment, electronics, and musical instruments.

:WOMBAT: [Waste Of Money, Brains, And Time] adj. Applied to problems which are both profoundly {uninteresting} in themselves and unlikely to benefit anyone interesting even if solved. Often used in fanciful constructions such as 'wrestling with a wombat'. See also {crawling horror}, {SMOP}. Also note the rather different usage as a metasyntactic variable in {{Commonwealth Hackish}}.

:wonky: /wong'kee/ [from Australian slang] adj. Yet another approximate synonym for {broken}. Specifically connotes a malfunction that produces behavior seen as crazy, humorous, or amusingly perverse. "That was the day the printer's font logic went wonky and everybody's listings came out in Tengwar." Also in 'wonked out'. See {funky}, {demented}, {bozotic}.

:woofer: [University of Waterloo] n. Some varieties of wide paper for printers have a perforation 8.5 inches from the left margin that allows the excess on the right-hand side to be torn off when the print format is 80 columns or less wide. The right-hand excess may be called 'woofer'. This term (like {tweeter}, which see) has been in use at Waterloo since 1972, but is elsewhere unknown. In audio jargon, the word refers to the bass speaker(s) on a hi-fi.

:workaround: n. A temporary {kluge} inserted in a system under development or test in order to avoid the effects of a {bug} or {misfeature} so that work can continue. Theoretically, workarounds are always replaced by {fix}es; in practice, customers often find themselves living with workarounds in the first couple of releases. "The code died on NUL characters in the input, so I fixed it to interpret them as spaces." "That's not a fix, that's a workaround!"

:working as designed: [IBM] adj. 1. In conformance to a wrong or inappropriate specification; useful, but misdesigned. 2. Frequently used as a sardonic comment on a program's utility. 3. Unfortunately also used as a bogus reason for not accepting a criticism or suggestion. At {IBM}, this sense is used in official documents! See {BAD}.

:worm: [from 'tapeworm' in John Brunner's novel 'The Shockwave Rider', via XEROX PARC] n. A program that propagates itself over a network, reproducing itself as it goes. Compare {virus}. Nowadays the term has negative connotations, as it is assumed that only {cracker}s write worms. Perhaps the best-known example was Robert T. Morris's 'Internet Worm' of 1988, a 'benign' one that got out of control and hogged hundreds of Suns and VAXen across the U.S. See also {cracker}, {RTM}, {Trojan horse}, {ice}, and {Great Worm, the}.

:wound around the axle: adj. In an infinite loop. Often used by older computer types.

:wrap around: vi. (also n. 'wraparound' and v. shorthand 'wrap') 1. [techspeak] The action of a counter that starts over at zero or at 'minus infinity' (see {infinity}) after its maximum value has been reached, and continues incrementing, either because it is programmed to do so or because of an overflow (as when a car's odometer starts over at 0). 2. To change {phase} gradually and continuously by maintaining a steady wake-sleep cycle somewhat longer than 24 hours, e.g., living six long (28-hour) days in a week (or, equivalently, sleeping at the rate of 10 microhertz). See also {phase-wrapping}.

:write-only code: [a play on 'read-only memory'] n. Code so arcane, complex, or ill-structured that it cannot be modified or even comprehended by anyone but its author, and possibly not even by him/her. A {Bad Thing}.

:write-only language: n. A language with syntax (or semantics) sufficiently dense and bizarre that any routine of significant size is {write-only code}. A sobriquet applied occasionally to C and often to APL, though {INTERCAL} and {TECO} certainly deserve it more.

:write-only memory: n. The obvious antonym to 'read-only memory'. Out of frustration with the long and seemingly useless chain of approvals required of component specifications, during which no actual checking seemed to occur, an engineer at Signetics once created a specification for a write-only memory and included it with a bunch of other specifications to be approved. This inclusion came to the attention of Signetics {management} only when regular customers started calling and asking for pricing information. Signetics published a corrected edition of the data book and requested the return of the 'erroneous' ones. Later, around 1974, Signetics bought a double-page spread in 'Electronics' magazine's April issue and used the spec as an April Fools' Day joke. Instead of the more conventional characteristic curves, the 25120 "fully encoded, 9046 x N, Random Access, write-only-memory" data sheet included diagrams of "bit capacity vs. Temp.", "Iff vs. Vff", "Number of pins remaining vs. number of socket insertions", and "AQL vs. selling price". The 25120 required a 6.3 VAC VFF supply, a +10V VCC, and VDD of 0V, +/- 2%.

:Wrong Thing: n. A design, action, or decision that is clearly incorrect or inappropriate. Often capitalized; always emphasized in speech as if capitalized. The opposite of the {Right Thing}; more generally, anything that is not the Right Thing. In cases where 'the good is the enemy of the best', the merely good —- although good —- is nevertheless the Wrong Thing. "In C, the default is for module-level declarations to be visible everywhere, rather than just within the module. This is clearly the Wrong Thing."

:wugga wugga: /wuh'g* wuh'g*/ n. Imaginary sound that a computer program makes as it labors with a tedious or difficult task. Compare {cruncha cruncha cruncha}, {grind} (sense 4).

:WYSIAYG: /wiz'ee-ayg/ adj. Describes a user interface under which "What You See Is *All* You Get"; an unhappy variant of {WYSIWYG}. Visual, 'point-and-shoot'-style interfaces tend to have easy initial learning curves, but also to lack depth; they often frustrate advanced users who would be better served by a command-style interface. When this happens, the frustrated user has a WYSIAYG problem. This term is most often used of editors, word processors, and document formatting programs. WYSIWYG 'desktop publishing' programs, for example, are a clear win for creating small documents with lots of fonts and graphics in them, especially things like newsletters and presentation slides. When typesetting book-length manuscripts, on the other hand, scale changes the nature of the task; one quickly runs into WYSIAYG limitations, and the increased power and flexibility of a command-driven formatter like TeX or UNIX's 'troff(1)' becomes not just desirable but a necessity.

:WYSIWYG: /wiz'ee-wig/ adj. Describes a user interface under which "What You See Is What You Get", as opposed to one that uses more-or-less obscure commands which do not result in immediate visual feedback. True WYSIWYG in environments supporting multiple fonts or graphics is a a rarely-attained ideal; there are variants of this term to express real-world manifestations including WYSIAWYG (What You See Is *Almost* What You Get) and WYSIMOLWYG (What You See Is More or Less What You Get). All these can be mildly derogatory, as they are often used to refer to dumbed-down {user-friendly} interfaces targeted at non-programmers; a hacker has no fear of obscure commands (compare {WYSIAYG}). On the other hand, {EMACS} was one of the very first WYSIWYG editors, replacing (actually, at first overlaying) the extremely obscure, command-based {TECO}. See also {WIMP environment}. [Oddly enough, WYSIWYG has already made it into the OED, in lower case yet. —- ESR]

= X = =====

:X: /X/ n. 1. Used in various speech and writing contexts (also in lowercase) in roughly its algebraic sense of 'unknown within a set defined by context' (compare {N}). Thus, the abbreviation 680x0 stands for 68000, 68010, 68020, 68030, or 68040, and 80x86 stands for 80186, 80286 80386 or 80486 (note that a UNIX hacker might write these as 680[0-4]0 and 80[1-4]86 or 680?0 and 80?86 respectively; see {glob}). 2. [after the name of an earlier window system called 'W'] An over-sized, over-featured, over-engineered and incredibly over-complicated window system developed at MIT and widely used on UNIX systems.

:XEROX PARC: The famed Palo Alto Research Center. For more than a decade, from the early 1970s into the mid-1980s, PARC yielded an astonishing volume of groundbreaking hardware and software innovations. The modern mice, windows, and icons style of software interface was invented there. So was the laser printer, and the local-area network; and PARC's series of D machines anticipated the poweful personal computers of the 1980s by a decade. Sadly, these prophets were without honor in their own company; so much so that it became a standard joke to describe PARC as a place characterized by developing brilliant ideas for everyone else.

:XOFF: /X'of/ n. Syn. {control-S}.

:XON: /X'on/ n. Syn. {control-Q}.

:xor: /X'or/, /kzor/ conj. Exclusive or. 'A xor B' means 'A or B, but not both'. "I want to get cherry pie xor a banana split." This derives from the technical use of the term as a function on truth-values that is true if exactly one of its two arguments is true.

:xref: /X'ref/ vt., n. Hackish standard abbreviation for 'cross-reference'.

:XXX: /X-X-X/ n. A marker that attention is needed. Commonly used in program comments to indicate areas that are kluged up or need to be. Some hackers liken 'XXX' to the notional heavy-porn movie rating.

:xyzzy: /X-Y-Z-Z-Y/, /X-Y-ziz'ee/, /ziz'ee/, or /ik-ziz'ee/ [from the ADVENT game] adj. 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!" 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". See also {plugh}.

= Y = =====

:YA-: [Yet Another] abbrev. In hackish acronyms this almost invariably expands to {Yet Another}, following the precedent set by UNIX 'yacc(1)' (Yet Another Compiler-Compiler). See {YABA}.

:YABA: /ya'b*/ [Cambridge] n. 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}.

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

:Yellow Book: [proposed] n. The print version of this Jargon File; 'The New Hacker's Dictionary', MIT Press, 1991 (ISBN 0-262-68069-6). Includes all the material in the 2.9.6 version of 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.

:yellow wire: [IBM] n. 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}.

: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}.

:You are not expected to understand this: cav. [UNIX] 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.

: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.