:The `-P' convention: --------------------- Turning a word into a question by appending the syllable `P'; from the LISP convention of appending the letter `P' to denote a predicate (a boolean-valued function). The question should expect a yes/no answer, though it needn't. (See T and NIL.) At dinnertime: Q: "Foodp?" A: "Yeah, I'm pretty hungry." or "T!" At any time: Q: "State-of-the-world-P?" A: (Straight) "I'm about to go home." A: (Humorous) "Yes, the world has a state." On the phone to Florida: Q: "State-p Florida?" A: "Been reading JARGON.TXT again, eh?" [One of the best of these is a Gosperism. Once, when we were at a Chinese restaurant, Bill Gosper wanted to know whether someone would like to share with him a two-person-sized bowl of soup. His inquiry was: "Split-p soup?" --- GLS]
:T: /T/ 1. [from LISP terminology for `true'] Yes. Used in reply to a question (particularly one asked using The `-P' convention ). In LISP, the constant T means `true', among other things. Some hackers use `T' and `NIL' instead of `Yes' and `No' almost reflexively. This sometimes causes misunderstandings. When a waiter or flight attendant asks whether a hacker wants coffee, he may well respond `T', meaning that he wants coffee; but of course he will be brought a cup of tea instead. As it happens, most hackers (particularly those who frequent Chinese restaurants) like tea at least as well as coffee --- so it is not that big a problem. 2. See time T (also since time T equals minus infinity). 3. [techspeak] In transaction-processing circles, an abbreviation for the noun `transaction'. 4. [Purdue] Alternate spelling of tee. 5. A dialect of LISP developed at Yale.
:tail recursion: n. If you aren't sick of it already, see tail recursion .
:talk mode: n. A feature supported by UNIX, ITS, and some other OSes that allows two or more logged-in users to set up a real-time on-line conversation. It combines the immediacy of talking with all the precision (and verbosity) that written language entails. It is difficult to communicate inflection, though conventions have arisen for some of these (see the section on writing style in the Prependices for details). Talk mode has a special set of jargon words, used to save typing, which are not used orally. Some of these are identical to (and probably derived from) Morse-code jargon used by ham-radio amateurs since the 1920s. BCNU be seeing you BTW by the way BYE? are you ready to unlink? (this is the standard way to end a talk-mode conversation; the other person types `BYE' to confirm, or else continues the conversation) CUL see you later ENQ? are you busy? (expects `ACK' or `NAK' in return) FOO? are you there? (often used on unexpected links, meaning also "Sorry if I butted in ..." (linker) or "What's up?" (linkee)) FWIW for what it's worth FYI for your information FYA for your amusement GA go ahead (used when two people have tried to type simultaneously; this cedes the right to type to the other) GRMBL grumble (expresses disquiet or disagreement) HELLOP hello? (an instance of the `-P' convention) JAM just a minute (equivalent to `SEC....') MIN same as `JAM' NIL no (see NIL) O over to you OO over and out / another form of "over to you" (from x/y as "x over y") \ lambda (used in discussing LISPy things) OBTW oh, by the way R U THERE? are you there? SEC wait a second (sometimes written `SEC...') T yes (see the main entry for T) TNX thanks TNX 1.0E6 thanks a million (humorous) TNXE6 another form of "thanks a million" WRT with regard to, or with respect to. WTF the universal interrogative particle; WTF knows what it means? WTH what the hell? <double newline> When the typing party has finished, he/she types two newlines to signal that he/she is done; this leaves a blank line between `speeches' in the conversation, making it easier to reread the preceding text. <name>: When three or more terminals are linked, it is conventional for each typist to prepend his/her login name or handle and a colon (or a hyphen) to each line to indicate who is typing (some conferencing facilities do this automatically). The login name is often shortened to a unique prefix (possibly a single letter) during a very long conversation. /\/\/\ A giggle or chuckle. On a MUD, this usually means `earthquake fault'. Most of the above sub-jargon is used at both Stanford and MIT. Several of these expressions are also common in email, esp. FYI, FYA, BTW, BCNU, WTF, and CUL. A few other abbreviations have been reported from commercial networks, such as GEnie and CompuServe, where on-line `live' chat including more than two people is common and usually involves a more `social' context, notably the following: <g> grin <gr&d> grinning, running, and ducking BBL be back later BRB be right back HHOJ ha ha only joking HHOK ha ha only kidding HHOS ha ha only serious IMHO in my humble opinion (see IMHO) LOL laughing out loud NHOH Never Heard of Him/Her (often used in initgame) ROTF rolling on the floor ROTFL rolling on the floor laughing AFK away from keyboard b4 before CU l8tr see you later MORF male or female? TTFN ta-ta for now TTYL talk to you later OIC oh, I see rehi hello again Most of these are not used at universities or in the UNIX world, though ROTF and TTFN have gained some currency there and IMHO is common; conversely, most of the people who know these are unfamiliar with FOO?, BCNU, HELLOP, NIL, and T. The MUD community uses a mixture of USENET/Internet emoticons, a few of the more natural of the old-style talk-mode abbrevs, and some of the `social' list above; specifically, MUD respondents report use of BBL, BRB, LOL, b4, BTW, WTF, TTFN, and WTH. The use of `rehi' is also common; in fact, mudders are fond of re- compounds and will frequently `rehug' or `rebonk' (see bonk/oif) people. The word `re' by itself is taken as `regreet'. In general, though, MUDders express a preference for typing things out in full rather than using abbreviations; this may be due to the relative youth of the MUD cultures, which tend to include many touch typists and to assume high-speed links. The following uses specific to MUDs are reported: CU l8er see you later (mutant of `CU l8tr') FOAD fuck off and die (use of this is generally OTT) OTT over the top (excessive, uncalled for) ppl abbrev for "people" THX thanks (mutant of `TNX'; clearly this comes in batches of 1138 (the Lucasian K)). UOK? are you OK? Some BIFFisms (notably the variant spelling `d00d') appear to be passing into wider use among some subgroups of MUDders. One final note on talk mode style: neophytes, when in talk mode, often seem to think they must produce letter-perfect prose because they are typing rather than speaking. This is not the best approach. It can be very frustrating to wait while your partner pauses to think of a word, or repeatedly makes the same spelling error and backs up to fix it. It is usually best just to leave typographical errors behind and plunge forward, unless severe confusion may result; in that case it is often fastest just to type "xxx" and start over from before the mistake. See also hakspek, emoticon.
:talker system: n. British hackerism for software that enables real-time chat or talk mode.
:tall card: n. A PC/AT-size expansion card (these can be larger than IBM PC or XT cards because the AT case is bigger). See also short card. When IBM introduced the PS/2 model 30 (its last gasp at supporting the ISA) they made the case lower and many industry-standard tall cards wouldn't fit; this was felt to be a reincarnation of the connector conspiracy, done with less style.
:tanked: adj. Same as down, used primarily by UNIX hackers. See also hosed. Popularized as a synonym for `drunk' by Steve Dallas in the late lamented "Bloom County" comic strip.
:TANSTAAFL: /tan'stah-fl/ [acronym, from Robert Heinlein's classic "The Moon is a Harsh Mistress".] "There Ain't No Such Thing As A Free Lunch", often invoked when someone is balking at the prospect of using an unpleasantly heavyweight technique, or at the poor quality of some piece of free software, or at the signal-to-noise ratio of unmoderated USENET newsgroups. "What? Don't tell me I have to implement a database back end to get my address book program to work!" "Well, TANSTAAFL you know." This phrase owes some of its popularity to the high concentration of science-fiction fans and political libertarians in hackerdom (see Appendix B).
:tar and feather: [from UNIX `tar(1)'] vt. To create a transportable archive from a group of files by first sticking them together with `tar(1)' (the Tape ARchiver) and then compressing the result (see compress). The latter action is dubbed `feathering' partly for euphony and (if only for contrived effect) by analogy to what you do with an airplane propeller to decrease wind resistance, or with an oar to reduce water resistance; smaller files, after all, slip through comm links more easily.
:taste: [primarily MIT] n. 1. The quality in a program that tends to be inversely proportional to the number of features, hacks, and kluges programmed into it. Also `tasty', `tasteful', `tastefulness'. "This feature comes in N tasty flavors." Although `tasteful' and `flavorful' are essentially synonyms, `taste' and flavor are not. Taste refers to sound judgment on the part of the creator; a program or feature can *exhibit* taste but cannot *have* taste. On the other hand, a feature can have flavor. Also, flavor has the additional meaning of `kind' or `variety' not shared by `taste'. Flavor is a more popular word than `taste', though both are used. See also elegant. 2. Alt. sp. of tayste.
:tayste: /tayst/ n. Two bits; also as taste. Syn. crumb, quarter. Compare byte, dynner, playte, nybble, quad.
:TCB: /T-C-B/ [IBM] n. 1. Trouble Came Back. An intermittent or difficult-to-reproduce problem that has failed to respond to neglect or shotgun debugging. Compare heisenbug. Not to be confused with: 2. Trusted Computing Base, an `official' jargon term from the Orange Book.
:tea, ISO standard cup of: [South Africa] n. A cup of tea with milk and one teaspoon of sugar, where the milk is poured into the cup before the tea. Variations are ISO 0, with no sugar; ISO 2, with two spoons of sugar; and so on. Like many ISO standards, this one has a faintly alien ring in North America, where hackers generally shun the decadent British practice of adulterating perfectly good tea with dairy products and prefer instead to add a wedge of lemon, if anything. If one were feeling extremely silly, one might hypothesize an analogous `ANSI standard cup of tea' and wind up with a political situation distressingly similar to several that arise in much more serious technical contexts. Milk and lemon don't mix very well.
:TechRef: /tek'ref/ [MS-DOS] n. The original "IBM PC Technical Reference Manual", including the BIOS listing and complete schematics for the PC. The only PC documentation in the issue package that's considered serious by real hackers.
:TECO: /tee'koh/ obs. 1. [originally an acronym for `[paper] Tape Editor and COrrector'; later, `Text Editor and COrrector'] n. A text editor developed at MIT and modified by just about everybody. With all the dialects included, TECO may have been the most prolific editor in use before EMACS, to which it was directly ancestral. Noted for its powerful programming-language-like features and its unspeakably hairy syntax. It is literally the case that every string of characters is a valid TECO program (though probably not a useful one); one common game used to be mentally working out what the TECO commands corresponding to human names did. 2. vt. Originally, to edit using the TECO editor in one of its infinite variations (see below). 3. vt.,obs. To edit even when TECO is *not* the editor being used! This usage is rare and now primarily historical. As an example of TECO's obscurity, here is a TECO program that takes a list of names such as: Loser, J. Random Quux, The Great Dick, Moby sorts them alphabetically according to surname, and then puts the surname last, removing the comma, to produce the following: Moby Dick J. Random Loser The Great Quux The program is [1 J^P$L$$ J <.-Z; .,(S,$ -D .)FX1 @F^B $K :L I $ G1 L>$$ (where ^B means `Control-B' (ASCII 0000010) and $ is actually an alt or escape (ASCII 0011011) character). In fact, this very program was used to produce the second, sorted list from the first list. The first hack at it had a bug: GLS (the author) had accidentally omitted the `@' in front of `F^B', which as anyone can see is clearly the Wrong Thing. It worked fine the second time. There is no space to describe all the features of TECO, but it may be of interest that `^P' means `sort' and `J<.-Z; ... L>' is an idiomatic series of commands for `do once for every line'. In mid-1991, TECO is pretty much one with the dust of history, having been replaced in the affections of hackerdom by EMACS. Descendants of an early (and somewhat lobotomized) version adopted by DEC can still be found lurking on VMS and a couple of crufty PDP-11 operating systems, however, and ports of the more advanced MIT versions remain the focus of some antiquarian interest. See also retrocomputing, write-only language.
:tee: n.,vt. [Purdue] A carbon copy of an electronic transmission. "Oh, you're sending him the bits to that? Slap on a tee for me." From the UNIX command `tee(1)', itself named after a pipe fitting (see plumbing). Can also mean `save one for me', as in "Tee a slice for me!" Also spelled `T'.
:teledildonics: /tel`*-dil-do'-niks/ n. Sex in a computer simulated virtual reality, esp. computer-mediated sexual interaction between the VR presences of two humans. This practice is not yet possible except in the rather limited form of erotic conversation on MUDs and the like. The term, however, is widely recognized in the VR community as a ha ha only serious projection of things to come. "When we can sustain a multi-sensory surround good enough for teledildonics, *then* we'll know we're getting somewhere."
:Telerat: /tel'*-rat/ n. Unflattering hackerism for `Teleray', a line of extremely losing terminals. Compare AIDX, Macintrash Nominal Semidestructor, Open DeathTrap, ScumOS, sun-stools, HP-SUX.
:TELNET: /tel'net/ vt. To communicate with another Internet host using the TELNET (RFC 854) protocol (usually using a program of the same name). TOPS-10 people used the word IMPCOM, since that was the program name for them. Sometimes abbreviated to TN /T-N/. "I usually TN over to SAIL just to read the AP News."
:ten-finger interface: n. The interface between two networks that cannot be directly connected for security reasons; refers to the practice of placing two terminals side by side and having an operator read from one and type into the other.
:tense: adj. Of programs, very clever and efficient. A tense piece of code often got that way because it was highly bummed, but sometimes it was just based on a great idea. A comment in a clever routine by Mike Kazar, once a grad-student hacker at CMU: "This routine is so tense it will bring tears to your eyes." A tense programmer is one who produces tense code.
:tenured graduate student: n. One who has been in graduate school for 10 years (the usual maximum is 5 or 6): a `ten-yeared' student (get it?). Actually, this term may be used of any grad student beginning in his seventh year. Students don't really get tenure, of course, the way professors do, but a tenth-year graduate student has probably been around the university longer than any untenured professor.
:tera-: /te'r*/ [SI] pref. See quantifiers.
:teraflop club: /te'r*-flop kluhb/ [FLOP = Floating Point Operation] n. A mythical association of people who consume outrageous amounts of computer time in order to produce a few simple pictures of glass balls with intricate ray-tracing techniques. Caltech professor James Kajiya is said to have been the founder.
:terminak: /ter'mi-nak`/ [Caltech, ca. 1979] n. Any malfunctioning computer terminal. A common failure mode of Lear-Siegler ADM 3a terminals caused the `L' key to produce the `K' code instead; complaints about this tended to look like "Terminak #3 has a bad keyboard. Pkease fix." See AIDX, Nominal Semidestructor, Open DeathTrap, ScumOS, sun-stools, Telerat, HP-SUX.
:terminal brain death: n. The extreme form of terminal illness (sense 1). What someone who has obviously been hacking continuously for far too long is said to be suffering from.
:terminal illness: n. 1. Syn. raster burn. 2. The `burn-in' condition your CRT tends to get if you don't have a screen saver.
:terminal junkie: [UK] n. A wannabee or early larval stage hacker who spends most of his or her time wandering the directory tree and writing noddy programs just to get a fix of computer time. Variants include `terminal jockey', `console junkie', and console jockey. The term `console jockey' seems to imply more expertise than the other three (possibly because of the exalted status of the console relative to an ordinary terminal). See also twink, read-only user .
:terpri: /ter'pree/ [from LISP 1.5 (and later, MacLISP)] vi. To output a newline. Now rare as jargon, though still used as techspeak in Common LISP. It is a contraction of `TERminate PRInt line', named for the fact that, on some early OSes and hardware, no characters would be printed until a complete line was formed, so this operation terminated the line and emitted the output.
:test: n. 1. Real users bashing on a prototype long enough to get thoroughly acquainted with it, with careful monitoring and followup of the results. 2. Some bored random user trying a couple of the simpler features with a developer looking over his or her shoulder, ready to pounce on mistakes. Judging by the quality of most software, the second definition is far more prevalent. See also demo.
:TeX:: /tekh/ n. An extremely powerful macro-based text formatter written by Donald E. Knuth, very popular in the computer-science community (it is good enough to have displaced UNIX troff, the other favored formatter, even at many UNIX installations). TeX fans insist on the correct (guttural) pronunciation, and the correct spelling (all caps, squished together, with the E depressed below the baseline; the mixed-case `TeX' is considered an acceptable kluge on ASCII-only devices). Fans like to proliferate names from the word `TeX' --- such as TeXnician (TeX user), TeXhacker (TeX programmer), TeXmaster (competent TeX programmer), TeXhax, and TeXnique. Knuth began TeX because he had become annoyed at the declining quality of the typesetting in volumes I--III of his monumental "Art of Computer Programming" (see Knuth, also bible). In a manifestation of the typical hackish urge to solve the problem at hand once and for all, he began to design his own typesetting language. He thought he would finish it on his sabbatical in 1978; he was wrong by only about 8 years. The language was finally frozen around 1985, but volume IV of "The Art of Computer Programming" has yet to appear as of mid-1993. The impact and influence of TeX's design has been such that nobody minds this very much. Many grand hackish projects have started as a bit of toolsmithing on the way to something else; Knuth's diversion was simply on a grander scale than most. TeX has also been a noteworthy example of free, shared, but high-quality software. Knuth used to offer monetary awards to people who found and reported bugs in it; as the years wore on and the few remaining bugs were fixed (and new ones even harder to find), the bribe went up. Though well-written, TeX is so large (and so full of cutting edge technique) that it is said to have unearthed at least one bug in every Pascal system it has been compiled with.
:text: n. 1. [techspeak] Executable code, esp. a `pure code' portion shared between multiple instances of a program running in a multitasking OS. Compare English. 2. Textual material in the mainstream sense; data in ordinary ASCII or EBCDIC representation (see flat-ASCII). "Those are text files; you can review them using the editor." These two contradictory senses confuse hackers, too.
:thanks in advance: [USENET] Conventional net.politeness ending a posted request for information or assistance. Sometimes written `advTHANKSance' or `aTdHvAaNnKcSe' or abbreviated `TIA'. See net.-, netiquette.
:That's not a bug, that's a feature!: The canonical first parry in a debate about a purported bug. The complainant, if unconvinced, is likely to retort that the bug is then at best a misfeature. See also feature.
:the X that can be Y is not the true X: Yet another instance of hackerdom's peculiar attraction to mystical references --- a common humorous way of making exclusive statements about a class of things. The template is from the "Tao te Ching": "The Tao which can be spoken of is not the true Tao." The implication is often that the X is a mystery accessible only to the enlightened. See the trampoline entry for an example, and compare has the X nature.
:theology: n. 1. Ironically or humorously used to refer to religious issues. 2. Technical fine points of an abstruse nature, esp. those where the resolution is of theoretical interest but is relatively marginal with respect to actual use of a design or system. Used esp. around software issues with a heavy AI or language-design component, such as the smart-data vs. smart-programs dispute in AI.
:theory: n. The consensus, idea, plan, story, or set of rules that is currently being used to inform a behavior. This usage is a generalization and (deliberate) abuse of the technical meaning. "What's the theory on fixing this TECO loss?" "What's the theory on dinner tonight?" ("Chinatown, I guess.") "What's the current theory on letting lusers on during the day?" "The theory behind this change is to fix the following well-known screw...."
:thinko: /thing'koh/ [by analogy with `typo'] n. A momentary, correctable glitch in mental processing, especially one involving recall of information learned by rote; a bubble in the stream of consciousness. Syn. braino; see also brain fart. Compare mouso.
:This can't happen: Less clipped variant of can't happen.
:This time, for sure!: excl. Ritual affirmation frequently uttered during protracted debugging sessions involving numerous small obstacles (e.g., attempts to bring up a UUCP connection). For the proper effect, this must be uttered in a fruity imitation of Bullwinkle J. Moose. Also heard: "Hey, Rocky! Watch me pull a rabbit out of my hat!" The canonical response is, of course, "But that trick *never* works!" See Humor, Hacker.
:thrash: vi. To move wildly or violently, without accomplishing anything useful. Paging or swapping systems that are overloaded waste most of their time moving data into and out of core (rather than performing useful computation) and are therefore said to thrash. Someone who keeps changing his mind (esp. about what to work on next) is said to be thrashing. A person frantically trying to execute too many tasks at once (and not spending enough time on any single task) may also be described as thrashing. Compare multitask.
:thread: n. [USENET, GEnie, CompuServe] Common abbreviation of `topic thread', a more or less continuous chain of postings on a single topic. To `follow a thread' is to read a series of USENET postings sharing a common subject or (more correctly) which are connected by Reference headers. The better newsreaders can present news in thread order automatically.
:three-finger salute: n. Syn. Vulcan nerve pinch.
:thud: n. 1. Yet another metasyntactic variable (see foo). It is reported that at CMU from the mid-1970s the canonical series of these was `foo', `bar', `thud', `blat'. 2. Rare term for the hash character, `#' (ASCII 0100011). See ASCII for other synonyms.
:thumb: n. The slider on a window-system scrollbar. So called because moving it allows you to browse through the contents of a text window in a way analogous to thumbing through a book.
:thunk: /thuhnk/ n. 1. "A piece of coding which provides an address", according to P. Z. Ingerman, who invented thunks in 1961 as a way of binding actual parameters to their formal definitions in Algol-60 procedure calls. If a procedure is called with an expression in the place of a formal parameter, the compiler generates a thunk which computes the expression and leaves the address of the result in some standard location. 2. Later generalized into: an expression, frozen together with its environment, for later evaluation if and when needed (similar to what in techspeak is called a `closure'). The process of unfreezing these thunks is called `forcing'. 3. A stubroutine, in an overlay programming environment, that loads and jumps to the correct overlay. Compare trampoline. 4. People and activities scheduled in a thunklike manner. "It occurred to me the other day that I am rather accurately modeled by a thunk --- I frequently need to be forced to completion." --- paraphrased from a plan file. Historical note: There are a couple of onomatopoeic myths circulating about the origin of this term. The most common is that it is the sound made by data hitting the stack; another holds that the sound is that of the data hitting an accumulator. Yet another suggests that it is the sound of the expression being unfrozen at argument-evaluation time. In fact, according to the inventors, it was coined after they realized (in the wee hours after hours of discussion) that the type of an argument in Algol-60 could be figured out in advance with a little compile-time thought, simplifying the evaluation machinery. In other words, it had `already been thought of'; thus it was christened a `thunk', which is "the past tense of `think' at two in the morning".
:tick: n. 1. A jiffy (sense 1). 2. In simulations, the discrete unit of time that passes between iterations of the simulation mechanism. In AI applications, this amount of time is often left unspecified, since the only constraint of interest is the ordering of events. This sort of AI simulation is often pejoratively referred to as `tick-tick-tick' simulation, especially when the issue of simultaneity of events with long, independent chains of causes is handwaved. 3. In the FORTH language, a single quote character.
:tick-list features: [Acorn Computers] n. Features in software or hardware that customers insist on but never use (calculators in desktop TSRs and that sort of thing). The American equivalent would be `checklist features', but this jargon sense of the phrase has not been reported.
:tickle a bug: vt. To cause a normally hidden bug to manifest itself through some known series of inputs or operations. "You can tickle the bug in the Paradise VGA card's highlight handling by trying to set bright yellow reverse video."
:tiger team: [U.S. military jargon] n. 1. Originally, a team whose purpose is to penetrate security, and thus test security measures. These people are paid professionals who do hacker-type tricks, e.g., leave cardboard signs saying "bomb" in critical defense installations, hand-lettered notes saying "Your codebooks have been stolen" (they usually haven't been) inside safes, etc. After a successful penetration, some high-ranking security type shows up the next morning for a `security review' and finds the sign, note, etc., and all hell breaks loose. Serious successes of tiger teams sometimes lead to early retirement for base commanders and security officers (see the patch entry for an example). 2. Recently, and more generally, any official inspection team or special firefighting group called in to look at a problem. A subset of tiger teams are professional crackers, testing the security of military computer installations by attempting remote attacks via networks or supposedly `secure' comm channels. Some of their escapades, if declassified, would probably rank among the greatest hacks of all times. The term has been adopted in commercial computer-security circles in this more specific sense.
:time bomb: n. A subspecies of logic bomb that is triggered by reaching some preset time, either once or periodically. There are numerous legends about time bombs set up by programmers in their employers' machines, to go off if the programmer is fired or laid off and is not present to perform the appropriate suppressing action periodically. Interestingly, the only such incident for which we have been pointed to documentary evidence took place in the Soviet Union in 1986! A disgruntled programmer at the Volga Automobile Plant (where the Fiat clones called Ladas were manufactured) planted a time bomb which, a week after he'd left on vacation, stopped the entire main assembly line for a day. The case attracted lots of attention in the Soviet Union because it was the first cracking case to make it to court there. The perpetrator got 3 years in jail.
:time sink: [poss. by analogy with `heat sink' or `current sink'] n. A project that consumes unbounded amounts of time.
:time T: /ti:m T/ n. 1. An unspecified but usually well-understood time, often used in conjunction with a later time T+1. "We'll meet on campus at time T or at Louie's at time T+1" means, in the context of going out for dinner: "We can meet on campus and go to Louie's, or we can meet at Louie's itself a bit later." (Louie's was a Chinese restaurant in Palo Alto that was a favorite with hackers.) Had the number 30 been used instead of the number 1, it would have implied that the travel time from campus to Louie's is 30 minutes; whatever time T is (and that hasn't been decided on yet), you can meet half an hour later at Louie's than you could on campus and end up eating at the same time. See also since time T equals minus infinity.
:times-or-divided-by: [by analogy with `plus-or-minus'] quant. Term occasionally used when describing the uncertainty associated with a scheduling estimate, for either humorous or brutally honest effect. For a software project, the scheduling uncertainty factor is usually at least 2.
:tip of the ice-cube: [IBM] n. The visible part of something small and insignificant. Used as an ironic comment in situations where `tip of the iceberg' might be appropriate if the subject were at all important.
:tired iron: [IBM] n. Hardware that is perfectly functional but far enough behind the state of the art to have been superseded by new products, presumably with sufficient improvement in bang-per-buck that the old stuff is starting to look a bit like a dinosaur.
: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 that became basics of the hackish vocabulary (see esp. foo, mung, 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 switches 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. 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/, [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." Compare fried.
: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, plumbing). 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 tools 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. Reportedy 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 computrons 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 Things 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 Things 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, FTP archives, or the Jargon File) looking for something of interest.
:tree-killer: [Sun] n. 1. A printer. 2. A person who wastes paper. This epithet should be interpreted in a broad sense; `wasting paper' includes the production of spiffy but content-free documents. Thus, most suits 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" (see also elvish, elder days).
:treeware: /tree'weir/ n. Printouts, books, and other information media made from pulped dead trees. Compare tree-killer, see documentation.
: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). Trits 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:: /T'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 Ossanna, modeled after the earlier ROFF which was in turn modeled after Multics' RUNOFF by Jerome Saltzer (*that* name came from the expression "to run off a copy"). 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 Ossanna'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 that, 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 malicious, security-breaking program that is disguised as something benign, such as a directory lister, archiver, game, or (in one notorious 1990 case on the Mac) a program to find and destroy viruses! See back door, virus, worm, phage, mockingbird.
: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'; compare spod.
: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 droids. 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 hooks 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 that 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 someone objected that `krans' meant `funeral wreath' in Swedish (though some Swedish speakers have since said it means simply `wreath'; this part of the story may be apocryphal). 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 users 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 (see also shotgun debugging). 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').
:twirling baton: [PLATO] n. The overstrike sequence -/|\-/|\- which produces an animated twirling baton. If you output it with a single backspace between characters, the baton spins in place. If you output the sequence BS SP between characters, the baton spins from left to right. If you output BS SP BS BS between characters, the batton spins from right to left. The twirling baton was a popular component of animated signature files on the pioneering PLATO educational timesharing system. The `archie' Internet service is perhaps the best-known baton program today; it uses the twirling baton as an idler indicating that the program is working on a query.
: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 ). The term 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 =
:The Meaning of `Hack': "The word hack doesn't really have 69 different meanings", according to MIT hacker Phil Agre. "In fact, hack has only one meaning, an extremely subtle and profound one which defies articulation. Which connotation is implied by a given use of the word depends in similarly profound ways on the context. Similar remarks apply to a couple of other hacker words, most notably random." Hacking might be characterized as `an appropriate application of ingenuity'. Whether the result is a quick-and-dirty patchwork job or a carefully crafted work of art, you have to admire the cleverness that went into it. An important secondary meaning of hack is `a creative practical joke'. This kind of hack is easier to explain to non-hackers than the programming kind. Of course, some hacks have both natures; see the lexicon entries for pseudo and kgbvax. But here are some examples of pure practical jokes that illustrate the hacking spirit: In 1961, students from Caltech (California Institute of Technology, in Pasadena) hacked the Rose Bowl football game. One student posed as a reporter and `interviewed' the director of the University of Washington card stunts (such stunts involve people in the stands who hold up colored cards to make pictures). The reporter learned exactly how the stunts were operated, and also that the director would be out to dinner later. While the director was eating, the students (who called themselves the `Fiendish Fourteen') picked a lock and stole a blank direction sheet for the card stunts. They then had a printer run off 2300 copies of the blank. The next day they picked the lock again and stole the master plans for the stunts --- large sheets of graph paper colored in with the stunt pictures. Using these as a guide, they made new instructions for three of the stunts on the duplicated blanks. Finally, they broke in once more, replacing the stolen master plans and substituting the stack of diddled instruction sheets for the original set. The result was that three of the pictures were totally different. Instead of `WASHINGTON', the word ``CALTECH' was flashed. Another stunt showed the word `HUSKIES', the Washington nickname, but spelled it backwards. And what was supposed to have been a picture of a husky instead showed a beaver. (Both Caltech and MIT use the beaver --- nature's engineer --- as a mascot.) After the game, the Washington faculty athletic representative said: "Some thought it ingenious; others were indignant." The Washington student body president remarked: "No hard feelings, but at the time it was unbelievable. We were amazed." This is now considered a classic hack, particularly because revising the direction sheets constituted a form of programming. Here is another classic hack: On November 20, 1982, MIT hacked the Harvard-Yale football game. Just after Harvard's second touchdown against Yale, in the first quarter, a small black ball popped up out of the ground at the 40-yard line, and grew bigger, and bigger, and bigger. The letters `MIT' appeared all over the ball. As the players and officials stood around gawking, the ball grew to six feet in diameter and then burst with a bang and a cloud of white smoke. The "Boston Globe" later reported: "If you want to know the truth, MIT won The Game." The prank had taken weeks of careful planning by members of MIT's Delta Kappa Epsilon fraternity. The device consisted of a weather balloon, a hydraulic ram powered by Freon gas to lift it out of the ground, and a vacuum-cleaner motor to inflate it. They made eight separate expeditions to Harvard Stadium between 1 and 5 A.M., locating an unused 110-volt circuit in the stadium and running buried wires from the stadium circuit to the 40-yard line, where they buried the balloon device. When the time came to activate the device, two fraternity members had merely to flip a circuit breaker and push a plug into an outlet. This stunt had all the earmarks of a perfect hack: surprise, publicity, the ingenious use of technology, safety, and harmlessness. The use of manual control allowed the prank to be timed so as not to disrupt the game (it was set off between plays, so the outcome of the game would not be unduly affected). The perpetrators had even thoughtfully attached a note to the balloon explaining that the device was not dangerous and contained no explosives. Harvard president Derek Bok commented: "They have an awful lot of clever people down there at MIT, and they did it again." President Paul E. Gray of MIT said: "There is absolutely no truth to the rumor that I had anything to do with it, but I wish there were." The hacks above are verifiable history; they can be proved to have happened. Many other classic-hack stories from MIT and elsewhere, though retold as history, have the characteristics of what Jan Brunvand has called `urban folklore' (see FOAF). Perhaps the best known of these is the legend of the infamous trolley-car hack, an alleged incident in which engineering students are said to have welded a trolley car to its tracks with thermite. Numerous versions of this have been recorded from the 1940s to the present, most set at MIT but at least one very detailed version set at CMU. Brian Leibowitz has researched MIT hacks both real and mythical extensively; the interested reader is referred to his delightful pictorial compendium "The Journal of the Institute for Hacks, Tomfoolery, and Pranks" (MIT Museum, 1990; ISBN 0-917027-03-5). Finally, here is a story about one of the classic computer hacks. Back in the mid-1970s, several of the system support staff at Motorola discovered a relatively simple way to crack system security on the Xerox CP-V timesharing system. Through a simple programming strategy, it was possible for a user program to trick the system into running a portion of the program in `master mode' (supervisor state), in which memory protection does not apply. The program could then poke a large value into its `privilege level' byte (normally write-protected) and could then proceed to bypass all levels of security within the file-management system, patch the system monitor, and do numerous other interesting things. In short, the barn door was wide open. Motorola quite properly reported this problem to Xerox via an official `level 1 SIDR' (a bug report with an intended urgency of `needs to be fixed yesterday'). Because the text of each SIDR was entered into a database that could be viewed by quite a number of people, Motorola followed the approved procedure: they simply reported the problem as `Security SIDR', and attached all of the necessary documentation, ways-to-reproduce, etc. The CP-V people at Xerox sat on their thumbs; they either didn't realize the severity of the problem, or didn't assign the necessary operating-system-staff resources to develop and distribute an official patch. Months passed. The Motorola guys pestered their Xerox field-support rep, to no avail. Finally they decided to take direct action, to demonstrate to Xerox management just how easily the system could be cracked and just how thoroughly the security safeguards could be subverted. They dug around in the operating-system listings and devised a thoroughly devilish set of patches. These patches were then incorporated into a pair of programs called `Robin Hood' and `Friar Tuck'. Robin Hood and Friar Tuck were designed to run as `ghost jobs' (daemons, in UNIX terminology); they would use the existing loophole to subvert system security, install the necessary patches, and then keep an eye on one another's statuses in order to keep the system operator (in effect, the superuser) from aborting them. One fine day, the system operator on the main CP-V software development system in El Segundo was surprised by a number of unusual phenomena. These included the following: * Tape drives would rewind and dismount their tapes in the middle of a job. * Disk drives would seek back and forth so rapidly that they would attempt to walk across the floor (see walking drives ). * The card-punch output device would occasionally start up of itself and punch a lace card. These would usually jam in the punch. * The console would print snide and insulting messages from Robin Hood to Friar Tuck, or vice versa. * The Xerox card reader had two output stackers; it could be instructed to stack into A, stack into B, or stack into A (unless a card was unreadable, in which case the bad card was placed into stacker B). One of the patches installed by the ghosts added some code to the card-reader driver... after reading a card, it would flip over to the opposite stacker. As a result, card decks would divide themselves in half when they were read, leaving the operator to recollate them manually. Naturally, the operator called in the operating-system developers. They found the bandit ghost jobs running, and X'ed them... and were once again surprised. When Robin Hood was X'ed, the following sequence of events took place: !X id1 id1: Friar Tuck... I am under attack! Pray save me! id1: Off (aborted) id2: Fear not, friend Robin! I shall rout the Sheriff of Nottingham's men! id1: Thank you, my good fellow! Each ghost-job would detect the fact that the other had been killed, and would start a new copy of the recently slain program within a few milliseconds. The only way to kill both ghosts was to kill them simultaneously (very difficult) or to deliberately crash the system. Finally, the system programmers did the latter --- only to find that the bandits appeared once again when the system rebooted! It turned out that these two programs had patched the boot-time OS image (the kernel file, in UNIX terms) and had added themselves to the list of programs that were to be started at boot time. The Robin Hood and Friar Tuck ghosts were finally eradicated when the system staff rebooted the system from a clean boot-tape and reinstalled the monitor. Not long thereafter, Xerox released a patch for this problem. It is alleged that Xerox filed a complaint with Motorola's management about the merry-prankster actions of the two employees in question. It is not recorded that any serious disciplinary action was taken against either of them.
:TV Typewriters: A Tale of Hackish Ingenuity Here is a true story about a glass tty: One day an MIT hacker was in a motorcycle accident and broke his leg. He had to stay in the hospital quite a while, and got restless because he couldn't hack. Two of his friends therefore took a terminal and a modem for it to the hospital, so that he could use the computer by telephone from his hospital bed. Now this happened some years before the spread of home computers, and computer terminals were not a familiar sight to the average person. When the two friends got to the hospital, a guard stopped them and asked what they were carrying. They explained that they wanted to take a computer terminal to their friend who was a patient. The guard got out his list of things that patients were permitted to have in their rooms: TV, radio, electric razor, typewriter, tape player, ... no computer terminals. Computer terminals weren't on the list, so the guard wouldn't let it in. Rules are rules, you know. (This guard was clearly a droid.) Fair enough, said the two friends, and they left again. They were frustrated, of course, because they knew that the terminal was as harmless as a TV or anything else on the list... which gave them an idea. The next day they returned, and the same thing happened: a guard stopped them and asked what they were carrying. They said: "This is a TV typewriter!" The guard was skeptical, so they plugged it in and demonstrated it. "See? You just type on the keyboard and what you type shows up on the TV screen." Now the guard didn't stop to think about how utterly useless a typewriter would be that didn't produce any paper copies of what you typed; but this was clearly a TV typewriter, no doubt about it. So he checked his list: "A TV is all right, a typewriter is all right ... okay, take it on in!" [Historical note: Many years ago, "Popular Electronics" published solder-it-yourself plans for a TV typewriter. Despite the essential uselessness of the device, it was an enormously popular project. Steve Ciarcia, the man behind "Byte" magazine's "Circuit Cellar" feature, resurrected this ghost in one of his books of the early 1980s. He ascribed its popularity (no doubt correctly) to the feeling of power the builder could achieve by being able to decide himself what would be shown on the TV. --- ESR] [Antihistorical note: On September 23rd, 1992, the L.A. Times ran the following bit of filler: Solomon Waters of Altadena, a 6-year-old first-grader, came home from his first day of school and excitedly told his mother how he had written on "a machine that looks like a computer -- but without the TV screen." She asked him if it could have been a "typewriter." "Yeah! Yeah!" he said. "That's what it was called." I have since investigated this matter and determined that many of today's teenagers have never seen a slide rule, either.... -- ESR]
:The Story of Mel, a Real Programmer: This was posted to USENET by its author, Ed Nather (utastro!nather), on May 21, 1983. A recent article devoted to the *macho* side of programming made the bald and unvarnished statement:
Real Programmers write in FORTRAN. Maybe they do now, in this decadent era of Lite beer, hand calculators, and "user-friendly" software but back in the Good Old Days, when the term "software" sounded funny and Real Computers were made out of drums and vacuum tubes, Real Programmers wrote in machine code. Not FORTRAN. Not RATFOR. Not, even, assembly language. Machine Code. Raw, unadorned, inscrutable hexadecimal numbers. Directly. Lest a whole new generation of programmers grow up in ignorance of this glorious past, I feel duty-bound to describe, as best I can through the generation gap, how a Real Programmer wrote code. I'll call him Mel, because that was his name. I first met Mel when I went to work for Royal McBee Computer Corp., a now-defunct subsidiary of the typewriter company. The firm manufactured the LGP-30, a small, cheap (by the standards of the day) drum-memory computer, and had just started to manufacture the RPC-4000, a much-improved, bigger, better, faster --- drum-memory computer. Cores cost too much, and weren't here to stay, anyway. (That's why you haven't heard of the company, or the computer.) I had been hired to write a FORTRAN compiler for this new marvel and Mel was my guide to its wonders. Mel didn't approve of compilers. "If a program can't rewrite its own code", he asked, "what good is it?" Mel had written, in hexadecimal, the most popular computer program the company owned. It ran on the LGP-30 and played blackjack with potential customers at computer shows. Its effect was always dramatic. The LGP-30 booth was packed at every show, and the IBM salesmen stood around talking to each other. Whether or not this actually sold computers was a question we never discussed. Mel's job was to re-write the blackjack program for the RPC-4000. (Port? What does that mean?) The new computer had a one-plus-one addressing scheme, in which each machine instruction, in addition to the operation code and the address of the needed operand, had a second address that indicated where, on the revolving drum, the next instruction was located. In modern parlance, every single instruction was followed by a GO TO! Put *that* in Pascal's pipe and smoke it. Mel loved the RPC-4000 because he could optimize his code: that is, locate instructions on the drum so that just as one finished its job, the next would be just arriving at the "read head" and available for immediate execution. There was a program to do that job, an "optimizing assembler", but Mel refused to use it. "You never know where it's going to put things", he explained, "so you'd have to use separate constants". It was a long time before I understood that remark. Since Mel knew the numerical value of every operation code, and assigned his own drum addresses, every instruction he wrote could also be considered a numerical constant. He could pick up an earlier "add" instruction, say, and multiply by it, if it had the right numeric value. His code was not easy for someone else to modify. I compared Mel's hand-optimized programs with the same code massaged by the optimizing assembler program, and Mel's always ran faster. That was because the "top-down" method of program design hadn't been invented yet, and Mel wouldn't have used it anyway. He wrote the innermost parts of his program loops first, so they would get first choice of the optimum address locations on the drum. The optimizing assembler wasn't smart enough to do it that way. Mel never wrote time-delay loops, either, even when the balky Flexowriter required a delay between output characters to work right. He just located instructions on the drum so each successive one was just *past* the read head when it was needed; the drum had to execute another complete revolution to find the next instruction. He coined an unforgettable term for this procedure. Although "optimum" is an absolute term, like "unique", it became common verbal practice to make it relative: "not quite optimum" or "less optimum" or "not very optimum". Mel called the maximum time-delay locations the "most pessimum". After he finished the blackjack program and got it to run ("Even the initializer is optimized", he said proudly), he got a Change Request from the sales department. The program used an elegant (optimized) random number generator to shuffle the "cards" and deal from the "deck", and some of the salesmen felt it was too fair, since sometimes the customers lost. They wanted Mel to modify the program so, at the setting of a sense switch on the console, they could change the odds and let the customer win. Mel balked. He felt this was patently dishonest, which it was, and that it impinged on his personal integrity as a programmer, which it did, so he refused to do it. The Head Salesman talked to Mel, as did the Big Boss and, at the boss's urging, a few Fellow Programmers. Mel finally gave in and wrote the code, but he got the test backwards, and, when the sense switch was turned on, the program would cheat, winning every time. Mel was delighted with this, claiming his subconscious was uncontrollably ethical, and adamantly refused to fix it. After Mel had left the company for greener pa$ture$, the Big Boss asked me to look at the code and see if I could find the test and reverse it. Somewhat reluctantly, I agreed to look. Tracking Mel's code was a real adventure. I have often felt that programming is an art form, whose real value can only be appreciated by another versed in the same arcane art; there are lovely gems and brilliant coups hidden from human view and admiration, sometimes forever, by the very nature of the process. You can learn a lot about an individual just by reading through his code, even in hexadecimal. Mel was, I think, an unsung genius. Perhaps my greatest shock came when I found an innocent loop that had no test in it. No test. *None*. Common sense said it had to be a closed loop, where the program would circle, forever, endlessly. Program control passed right through it, however, and safely out the other side. It took me two weeks to figure it out. The RPC-4000 computer had a really modern facility called an index register. It allowed the programmer to write a program loop that used an indexed instruction inside; each time through, the number in the index register was added to the address of that instruction, so it would refer to the next datum in a series. He had only to increment the index register each time through. Mel never used it. Instead, he would pull the instruction into a machine register, add one to its address, and store it back. He would then execute the modified instruction right from the register. The loop was written so this additional execution time was taken into account --- just as this instruction finished, the next one was right under the drum's read head, ready to go. But the loop had no test in it. The vital clue came when I noticed the index register bit, the bit that lay between the address and the operation code in the instruction word, was turned on --- yet Mel never used the index register, leaving it zero all the time. When the light went on it nearly blinded me. He had located the data he was working on near the top of memory --- the largest locations the instructions could address --- so, after the last datum was handled, incrementing the instruction address would make it overflow. The carry would add one to the operation code, changing it to the next one in the instruction set: a jump instruction. Sure enough, the next program instruction was in address location zero, and the program went happily on its way. I haven't kept in touch with Mel, so I don't know if he ever gave in to the flood of change that has washed over programming techniques since those long-gone days. I like to think he didn't. In any event, I was impressed enough that I quit looking for the offending test, telling the Big Boss I couldn't find it. He didn't seem surprised. When I left the company, the blackjack program would still cheat if you turned on the right sense switch, and I think that's how it should be. I didn't feel comfortable hacking up the code of a Real Programmer.This is one of hackerdom's great heroic epics, free verse or no. In a few spare images it captures more about the esthetics and psychology of hacking than all the scholarly volumes on the subject put together. For an opposing point of view, see the entry for real programmer. [1992 postscript --- the author writes: "The original submission to the net was not in free verse, nor any approximation to it --- it was straight prose style, in non-justified paragraphs. In bouncing around the net it apparently got modified into the `free verse' form now popular. In other words, it got hacked on the net. That seems appropriate, somehow."]
:Things Hackers Detest and Avoid: IBM mainframes. Smurfs, Ewoks, and other forms of offensive cuteness. Bureaucracies. Stupid people. Easy listening music. Television (except for cartoons, movies, and "Star Trek" classic). Business suits. Dishonesty. Incompetence. Boredom. COBOL. BASIC. Character-based menu interfaces.
:The Hitchhiker's Guide to the Galaxy: Douglas Adams Pocket Books, 1981 ISBN 0-671-46149-4 This `Monty Python in Space' spoof of SF genre traditions has been popular among hackers ever since the original British radio show. Read it if only to learn about Vogons (see bogon) and the significance of the number 42 (see random numbers) --- and why the winningest chess program of 1990 was called `Deep Thought'.
:The Tao of Programming: James Geoffrey Infobooks, 1987 ISBN 0-931137-07-1 This gentle, funny spoof of the "Tao Te Ching" contains much that is illuminating about the hacker way of thought. "When you have learned to snatch the error code from the trap frame, it will be time for you to leave."
:The Devil's DP Dictionary: Stan Kelly-Bootle McGraw-Hill, 1981 ISBN 0-07-034022-6 This pastiche of Ambrose Bierce's famous work is similar in format to the Jargon File (and quotes several entries from jargon-1) but somewhat different in tone and intent. It is more satirical and less anthropological, and is largely a product of the author's literate and quirky imagination. For example, it defines `computer science' as "a study akin to numerology and astrology, but lacking the precision of the former and the success of the latter" and "the boring art of coping with a large number of trivialities."
:The Devouring Fungus: Tales from the Computer Age: Karla Jennings Norton, 1990 ISBN 0-393-30732-8 The author of this pioneering compendium knits together a great deal of computer- and hacker-related folklore with good writing and a few well-chosen cartoons. She has a keen eye for the human aspects of the lore and is very good at illuminating the psychology and evolution of hackerdom. Unfortunately, a number of small errors and awkwardnesses suggest that she didn't have the final manuscript checked over by a native speaker; the glossary in the back is particularly embarrassing, and at least one classic tale (the Magic Switch story, retold here under A Story About `Magic' in appendix A) is given in incomplete and badly mangled form. Nevertheless, this book is a win overall and can be enjoyed by hacker and non-hacker alike.
:The Soul of a New Machine: Tracy Kidder Little, Brown, 1981 (paperback: Avon, 1982 ISBN 0-380-59931-7) This book (a 1982 Pulitzer Prize winner) documents the adventure of the design of a new Data General computer, the MV-8000 Eagle. It is an amazingly well-done portrait of the hacker mindset --- although largely the hardware hacker --- done by a complete outsider. It is a bit thin in spots, but with enough technical information to be entertaining to the serious hacker while providing non-technical people a view of what day-to-day life can be like --- the fun, the excitement, the disasters. During one period, when the microcode and logic were glitching at the nanosecond level, one of the overworked engineers departed the company, leaving behind a note on his terminal as his letter of resignation: "I am going to a commune in Vermont and will deal with no unit of time shorter than a season."
:True Names ... and Other Dangers: Vernor Vinge Baen Books, 1987 ISBN 0-671-65363-6 Hacker demigod Richard Stallman believes the title story of this book "expresses the spirit of hacking best". This may well be true; it's certainly difficult to recall a better job. The other stories in this collection are also fine work by an author who is perhaps one of today's very best practitioners of hard SF.
:Technobabble: John Barry MIT Press 1991 ISBN 0-262-02333-4 Barry's book takes a critical and humorous look at the `technobabble' of acronyms, neologisms, hyperbole, and metaphor spawned by the computer industry. Though he discusses some of the same mechanisms of jargon formation that occur in hackish, most of what he chronicles is actually suit-speak --- the obfuscatory language of press releases, marketroids, and Silicon Valley CEOs rather than the playful jargon of hackers (most of whom wouldn't be caught dead uttering the kind of pompous, passive-voiced word salad he deplores).
:The Cuckoo's Egg: Clifford Stoll Doubleday 1989 ISBN 0-385-24946-2 Clifford Stoll's absorbing tale of how he tracked Markus Hess and the Chaos Club cracking ring nicely illustrates the difference between `hacker' and `cracker'. Stoll's portrait of himself, his lady Martha, and his friends at Berkeley and on the Internet paints a marvelously vivid picture of how hackers and the people around them like to live and how they think. #====================== THE JARGON FILE ENDS HERE ======================#
HTML Conversion © 1999 Thomas Hövel Software 18.02.00 04:13:05 -0500