Chapter 35

To print a given document via a laser printer. "OK, let's lase that sucker and see if all those graphics-macro calls did the right things."

Node:laser chicken, Next:lasherism, Previous:lase, Up:= L =

laser chicken n.

Kung Pao Chicken, a standard Chinese dish containing chicken, peanuts, and hot red peppers in a spicy pepper-oil sauce. Many hackers call it `laser chicken' for two reasons: It can zap you just like a laser, and the sauce has a red color reminiscent of some laser beams. The dish has also been called `gunpowder chicken'.

In a variation on this theme, it is reported that some Australian hackers have redesignated the common dish `lemon chicken' as `Chernobyl Chicken'. The name is derived from the color of the sauce, which is considered bright enough to glow in the dark (as, mythically, do some of the inhabitants of Chernobyl).

Node:lasherism, Next:laundromat, Previous:laser chicken, Up:= L =

lasherism n.

[Harvard] A program that solves a standard problem (such as the Eight Queens puzzle or implementing the life algorithm) in a deliberately nonstandard way. Distinguished from a crock or kluge by the fact that the programmer did it on purpose as a mental exercise. Such constructions are quite popular in exercises such as the Obfuscated C Contest, and occasionally in retrocomputing. Lew Lasher was a student at Harvard around 1980 who became notorious for such behavior.

Node:laundromat, Next:LDB, Previous:lasherism, Up:= L =

laundromat n.

Syn. disk farm; see washing machine.

Node:LDB, Next:leaf site, Previous:laundromat, Up:= L =

LDB /l*'d*b/ vt.

[from the PDP-10 instruction set] To extract from the middle. "LDB me a slice of cake, please." This usage has been kept alive by Common LISP's function of the same name. Considered silly. See also DPB.

Node:leaf site, Next:leak, Previous:LDB, Up:= L =

leaf site n.,obs.

Before pervasive TCP/IP, this term was used of a machine that merely originated and read Usenet news or mail, and did not relay any third-party traffic. It was often uttered in a critical tone; when the ratio of leaf sites to backbone, rib, and other relay sites got too high, the network tended to develop bottlenecks. Compare backbone site, rib site. Now that traffic patterns depend more on the distribution of routers than of host machines this term has largely fallen out of use.

Node:leak, Next:leaky heap, Previous:leaf site, Up:= L =

leak n.

With qualifier, one of a class of resource-management bugs that occur when resources are not freed properly after operations on them are finished, so they effectively disappear (leak out). This leads to eventual exhaustion as new allocation requests come in. memory leak and fd leak have their own entries; one might also refer, to, say, a `window handle leak' in a window system.

Node:leaky heap, Next:leapfrog attack, Previous:leak, Up:= L =

leaky heap n.

[Cambridge] An arena with a memory leak.

Node:leapfrog attack, Next:leech, Previous:leaky heap, Up:= L =

leapfrog attack n.

Use of userid and password information obtained illicitly from one host (e.g., downloading a file of account IDs and passwords, tapping TELNET, etc.) to compromise another host. Also, the act of TELNETting through one or more hosts in order to confuse a trace (a standard cracker procedure).

Node:leech, Next:leech mode, Previous:leapfrog attack, Up:= L =

leech

1. n. (Also `leecher'.) Among BBS types, crackers and warez d00dz, one who consumes knowledge without generating new software, cracks, or techniques. BBS culture specifically defines a leech as someone who downloads files with few or no uploads in return, and who does not contribute to the message section. Cracker culture extends this definition to someone (a lamer, usually) who constantly presses informed sources for information and/or assistance, but has nothing to contribute. 2. v. [common, Toronto area] To instantly fetch a file (other than a mail attachment) whether by FTP or IRC file req or any other method. Seems to be a holdover from the early 1990s when Toronto had a very active BBS and warez scene.

Node:leech mode, Next:legal, Previous:leech, Up:= L =

leech mode n.

[warez d00dz] "Leech mode" or "leech access" or (simply "leech" as in "You get leech") is the access mode on a FTP site where one can download as many files as one wants, without having to upload. Leech mode is often promised on banner sites, but rarely obtained. See ratio site, banner site.

Node:legal, Next:legalese, Previous:leech mode, Up:= L =

legal adj.

Loosely used to mean `in accordance with all the relevant rules', esp. in connection with some set of constraints defined by software. "The older =+ alternate for += is no longer legal syntax in ANSI C." "This parser processes each line of legal input the moment it sees the trailing linefeed." Hackers often model their work as a sort of game played with the environment in which the objective is to maneuver through the thicket of `natural laws' to achieve a desired objective. Their use of `legal' is flavored as much by this game-playing sense as by the more conventional one having to do with courts and lawyers. Compare language lawyer, legalese.

Node:legalese, Next:LER, Previous:legal, Up:= L =

legalese n.

Dense, pedantic verbiage in a language description, product specification, or interface standard; text that seems designed to obfuscate and requires a language lawyer to parse it. Though hackers are not afraid of high information density and complexity in language (indeed, they rather enjoy both), they share a deep and abiding loathing for legalese; they associate it with deception, suits, and situations in which hackers generally get the short end of the stick.

Node:LER, Next:LERP, Previous:legalese, Up:= L =

LER /L-E-R/

n. 1. [TMRC, from `Light-Emitting Diode'] A light-emitting resistor (that is, one in the process of burning up). Ohm's law was broken. See also SED. 2. An incandescent light bulb (the filament emits light because it's resistively heated).

Node:LERP, Next:let the smoke out, Previous:LER, Up:= L =

LERP /lerp/ vi.,n.

Quasi-acronym for Linear Interpolation, used as a verb or noun for the operation. "Bresenham's algorithm lerps incrementally between the two endpoints of the line."

Node:let the smoke out, Next:letterbomb, Previous:LERP, Up:= L =

let the smoke out v.

To fry hardware (see fried). See magic smoke for a discussion of the underlying mythology.

Node:letterbomb, Next:lexer, Previous:let the smoke out, Up:= L =

letterbomb

1. n. A piece of email containing live data intended to do nefarious things to the recipient's machine or terminal. It used to be possible, for example, to send letterbombs that would lock up some specific kinds of terminals when they are viewed, so thoroughly that the user must cycle power (see cycle, sense 3) to unwedge them. Under Unix, a letterbomb can also try to get part of its contents interpreted as a shell command to the mailer. The results of this could range from silly to tragic; fortunately it has been some years since any of the standard Unix/Internet mail software was vulnerable to such an attack (though, as the Melissa virus attack demonstrated in early 1999, Microsoft systems can have serious problems). See also Trojan horse; compare nastygram. 2. Loosely, a mailbomb.

Node:lexer, Next:lexiphage, Previous:letterbomb, Up:= L =

lexer /lek'sr/ n.

Common hacker shorthand for `lexical analyzer', the input-tokenizing stage in the parser for a language (the part that breaks it into word-like pieces). "Some C lexers get confused by the old-style compound ops like =-."

Node:lexiphage, Next:life, Previous:lexer, Up:= L =

lexiphage /lek'si-fayj`/ n.

A notorious word chomper on ITS. See bagbiter. This program would draw on a selected victim's bitmapped terminal the words "THE BAG" in ornate letters, followed a pair of jaws biting pieces of it off.

Node:life, Next:Life is hard, Previous:lexiphage, Up:= L =

life n.

1. A cellular-automata game invented by John Horton Conway and first introduced publicly by Martin Gardner ("Scientific American", October 1970); the game's popularity had to wait a few years for computers on which it could reasonably be played, as it's no fun to simulate the cells by hand. Many hackers pass through a stage of fascination with it, and hackers at various places contributed heavily to the mathematical analysis of this game (most notably Bill Gosper at MIT, who even implemented life in TECO!; see Gosperism). When a hacker mentions `life', he is much more likely to mean this game than the magazine, the breakfast cereal, or the human state of existence. 2. The opposite of Usenet. As in "Get a life!"

Node:Life is hard, Next:light pipe, Previous:life, Up:= L =

Life is hard prov.

[XEROX PARC] This phrase has two possible interpretations: (1) "While your suggestion may have some merit, I will behave as though I hadn't heard it." (2) "While your suggestion has obvious merit, equally obvious circumstances prevent it from being seriously considered." The charm of the phrase lies precisely in this subtle but important ambiguity.

Node:light pipe, Next:lightweight, Previous:Life is hard, Up:= L =

light pipe n.

Fiber optic cable. Oppose copper.

Node:lightweight, Next:like kicking dead whales down the beach, Previous:light pipe, Up:= L =

lightweight adj.

Opposite of heavyweight; usually found in combining forms such as `lightweight process'.

Node:like kicking dead whales down the beach, Next:like nailing jelly to a tree, Previous:lightweight, Up:= L =

like kicking dead whales down the beach adj.

Describes a slow, difficult, and disgusting process. First popularized by a famous quote about the difficulty of getting work done under one of IBM's mainframe OSes. "Well, you could write a C compiler in COBOL, but it would be like kicking dead whales down the beach." See also fear and loathing.

Node:like nailing jelly to a tree, Next:line 666, Previous:like kicking dead whales down the beach, Up:= L =

like nailing jelly to a tree adj.

Used to describe a task thought to be impossible, esp. one in which the difficulty arises from poor specification or inherent slipperiness in the problem domain. "Trying to display the `prettiest' arrangement of nodes and arcs that diagrams a given graph is like nailing jelly to a tree, because nobody's sure what `prettiest' means algorithmically."

Hacker use of this term may recall mainstream slang originated early in the 20th century by President Theodore Roosevelt. There is a legend that, weary of inconclusive talks with Colombia over the right to dig a canal through its then-province Panama, he remarked, "Negotiating with those pirates is like trying to nail currant jelly to the wall." Roosevelt's government subsequently encouraged the anti-Colombian insurgency that created the nation of Panama.

Node:line 666, Next:line eater the, Previous:like nailing jelly to a tree, Up:= L =

line 666 [from Christian eschatological myth] n.

The notional line of source at which a program fails for obscure reasons, implying either that somebody is out to get it (when you are the programmer), or that it richly deserves to be so gotten (when you are not). "It works when I trace through it, but seems to crash on line 666 when I run it." "What happens is that whenever a large batch comes through, mmdf dies on the Line of the Beast. Probably some twit hardcoded a buffer size."

Node:line eater the, Next:line noise, Previous:line 666, Up:= L =

line eater, the n. obs.

[Usenet] 1. A bug in some now-obsolete versions of the netnews software that used to eat up to BUFSIZ bytes of the article text. The bug was triggered by having the text of the article start with a space or tab. This bug was quickly personified as a mythical creature called the `line eater', and postings often included a dummy line of `line eater food'. Ironically, line eater `food' not beginning with a space or tab wasn't actually eaten, since the bug was avoided; but if there was a space or tab before it, then the line eater would eat the food and the beginning of the text it was supposed to be protecting. The practice of `sacrificing to the line eater' continued for some time after the bug had been nailed to the wall, and is still humorously referred to. The bug itself was still occasionally reported to be lurking in some mail-to-netnews gateways as late as 1991. 2. See NSA line eater.

Node:line noise, Next:line starve, Previous:line eater the, Up:= L =

line noise n.

1. [techspeak] Spurious characters due to electrical noise in a communications link, especially an RS-232 serial connection. Line noise may be induced by poor connections, interference or crosstalk from other circuits, electrical storms, cosmic rays, or (notionally) birds crapping on the phone wires. 2. Any chunk of data in a file or elsewhere that looks like the results of line noise in sense 1. 3. Text that is theoretically a readable text or program source but employs syntax so bizarre that it looks like line noise in senses 1 or 2. Yes, there are languages this ugly. The canonical example is TECO; it is often claimed that "TECO's input syntax is indistinguishable from line noise." Other non-WYSIWYG editors, such as Multics qed and Unix ed, in the hands of a real hacker, also qualify easily, as do deliberately obfuscated languages such as INTERCAL.

Node:line starve, Next:linearithmic, Previous:line noise, Up:= L =

line starve

[MIT] 1. vi. To feed paper through a printer the wrong way by one line (most printers can't do this). On a display terminal, to move the cursor up to the previous line of the screen. "To print `X squared', you just output `X', line starve, `2', line feed." (The line starve causes the `2' to appear on the line above the `X', and the line feed gets back to the original line.) 2. n. A character (or character sequence) that causes a terminal to perform this action. ASCII 0011010, also called SUB or control-Z, was one common line-starve character in the days before microcomputers and the X3.64 terminal standard. Today, the term might be used for the ISO reverse line feed character 0x8D. Unlike `line feed', `line starve' is not standard ASCII terminology. Even among hackers it is considered a bit silly. 3. [proposed] A sequence such as \c (used in System V echo, as well as nroff and troff) that suppresses a newline or other character(s) that would normally be emitted.

Node:linearithmic, Next:link farm, Previous:line starve, Up:= L =

linearithmic adj.

Of an algorithm, having running time that is O(N log N). Coined as a portmanteau of `linear' and `logarithmic' in "Algorithms In C" by Robert Sedgewick (Addison-Wesley 1990, ISBN 0-201-51425-7).

Node:link farm, Next:link rot, Previous:linearithmic, Up:= L =

link farm n.

[Unix] A directory tree that contains many links to files in a master directory tree of files. Link farms save space when one is maintaining several nearly identical copies of the same source tree -- for example, when the only difference is architecture-dependent object files. "Let's freeze the source and then rebuild the FROBOZZ-3 and FROBOZZ-4 link farms." Link farms may also be used to get around restrictions on the number of -I (include-file directory) arguments on older C preprocessors. However, they can also get completely out of hand, becoming the filesystem equivalent of spaghetti code.

Node:link rot, Next:link-dead, Previous:link farm, Up:= L =

link rot n.

The natural decay of web links as the sites they're connected to change or die. Compare bit rot.

Node:link-dead, Next:lint, Previous:link rot, Up:= L =

link-dead adj.

[MUD] The state a player is in when they kill their connection to a MUD without leaving it properly. The player is then commonly left as a statue in the game, and is only removed after a certain period of time (an hour on most MUDs). Used on IRC as well, although it is inappropriate in that context. Compare netdead.

Node:lint, Next:Lintel, Previous:link-dead, Up:= L =

lint

[from Unix's lint(1), named for the bits of fluff it supposedly picks from programs] 1. vt. To examine a program closely for style, language usage, and portability problems, esp. if in C, esp. if via use of automated analysis tools, most esp. if the Unix utility lint(1) is used. This term used to be restricted to use of lint(1) itself, but (judging by references on Usenet) it has become a shorthand for desk check at some non-Unix shops, even in languages other than C. Also as v. delint. 2. n. Excess verbiage in a document, as in "This draft has too much lint".

Node:Lintel, Next:Linus, Previous:lint, Up:= L =

Lintel n.

The emerging Linux/Intel alliance. This term began to be used in early 1999 after it became clear that the Wintel alliance was under increasing strain and Intel started taking stakes in Linux companies.

Node:Linus, Next:Linux, Previous:Lintel, Up:= L =

Linus /leen'us'/ or /lin'us'/, not /li:'nus/

Linus Torvalds, the author of Linux. Nobody in the hacker culture has been as readily recognized by first name alone since Ken (Thompson).

Node:Linux, Next:lion food, Previous:Linus, Up:= L =

Linux /lee'nuhks/ or /li'nuks/, not /li:'nuhks/ n.

The free Unix workalike created by Linus Torvalds and friends starting about 1991. The pronunciation /lee'nuhks/ is preferred because the name `Linus' has an /ee/ sound in Swedish (Linus's family is part of Finland's 6% ethnic-Swedish minority). This may be the most remarkable hacker project in history -- an entire clone of Unix for 386, 486 and Pentium micros, distributed for free with sources over the net (ports to Alpha and Sparc and many other machines are also in use).

Linux is what GNU aimed to be, and it relies on the GNU toolset. But the Free Software Foundation didn't produce the kernel to go with that toolset until 1999, which was too late. Other, similar efforts like FreeBSD and NetBSD have been technically successful but never caught fire the way Linux has; as this is written in 2000, Linux is seriously challenging Microsoft's OS dominance. It has already captured 31% of the Internet-server market and 25% of general business servers.

An earlier version of this entry opined "The secret of Linux's success seems to be that Linus worked much harder early on to keep the development process open and recruit other hackers, creating a snowball effect." Truer than we knew. See bazaar.

(Some people object that the name `Linux' should be used to refer only to the kernel, not the entire operating system. This claim is a proxy for an underlying territorial dispute; people who insist on the term `GNU/Linux' want the the FSF to get most of the credit for Linux because RMS and friends wrote many of its user-level tools. Neither this theory nor the term `GNU/Linux' has gained more than minority acceptance).

Node:lion food, Next:Lions Book, Previous:Linux, Up:= L =

lion food n.

[IBM] Middle management or HQ staff (or, by extension, administrative drones in general). From an old joke about two lions who, escaping from the zoo, split up to increase their chances but agree to meet after 2 months. When they finally meet, one is skinny and the other overweight. The thin one says: "How did you manage? I ate a human just once and they turned out a small army to chase me -- guns, nets, it was terrible. Since then I've been reduced to eating mice, insects, even grass." The fat one replies: "Well, I hid near an IBM office and ate a manager a day. And nobody even noticed!"

Node:Lions Book, Next:LISP, Previous:lion food, Up:= L =

Lions Book n.

"Source Code and Commentary on Unix level 6", by John Lions. The two parts of this book contained (1) the entire source listing of the Unix Version 6 kernel, and (2) a commentary on the source discussing the algorithms. These were circulated internally at the University of New South Wales beginning 1976-77, and were, for years after, the only detailed kernel documentation available to anyone outside Bell Labs. Because Western Electric wished to maintain trade secret status on the kernel, the Lions Book was only supposed to be distributed to affiliates of source licensees. In spite of this, it soon spread by samizdat to a good many of the early Unix hackers.

[1996 update: The Lions book lives again! It was put back in print as ISBN 1-57398-013-7 from Peer-To-Peer Communications, with forewords by Dennis Ritchie and Ken Thompson. In a neat bit of reflexivity, the page before the contents quotes this entry.]

Node:LISP, Next:list-bomb, Previous:Lions Book, Up:= L =

LISP n.

[from `LISt Processing language', but mythically from `Lots of Irritating Superfluous Parentheses'] AI's mother tongue, a language based on the ideas of (a) variable-length lists and trees as fundamental data types, and (b) the interpretation of code as data and vice-versa. Invented by John McCarthy at MIT in the late 1950s, it is actually older than any other HLL still in use except FORTRAN. Accordingly, it has undergone considerable adaptive radiation over the years; modern variants are quite different in detail from the original LISP 1.5. The dominant HLL among hackers until the early 1980s, LISP now shares the throne with C. Its partisans claim it is the only language that is truly beautiful. See languages of choice.

All LISP functions and programs are expressions that return values; this, together with the high memory utilization of LISPs, gave rise to Alan Perlis's famous quip (itself a take on an Oscar Wilde quote) that "LISP programmers know the value of everything and the cost of nothing".

One significant application for LISP has been as a proof by example that most newer languages, such as COBOL and Ada, are full of unnecessary crocks. When the Right Thing has already been done once, there is no justification for bogosity in newer languages.

Node:list-bomb, Next:lithium lick, Previous:LISP, Up:= L =

list-bomb v.

To mailbomb someone by forging messages causing the victim to become a subscriber to many mailing lists. This is a self-defeating tactic; it merely forces mailing list servers to require confirmation by return message for every subscription.

Node:lithium lick, Next:little-endian, Previous:list-bomb, Up:= L =

lithium lick n.

[NeXT] Steve Jobs. Employees who have gotten too much attention from their esteemed founder are said to have `lithium lick' when they begin to show signs of Jobsian fervor and repeat the most recent catch phrases in normal conversation -- for example, "It just works, right out of the box!"

Node:little-endian, Next:live, Previous:lithium lick, Up:= L =

little-endian adj.

Describes a computer architecture in which, within a given 16- or 32-bit word, bytes at lower addresses have lower significance (the word is stored `little-end-first'). The PDP-11 and VAX families of computers and Intel microprocessors and a lot of communications and networking hardware are little-endian. See big-endian, middle-endian, NUXI problem. The term is sometimes used to describe the ordering of units other than bytes; most often, bits within a byte.

Node:live, Next:live data, Previous:little-endian, Up:= L =

live /li:v/ adj.,adv.

[common] Opposite of `test'. Refers to actual real-world data or a program working with it. For example, the response to "I think the record deleter is finished" might be "Is it live yet?" or "Have you tried it out on live data?" This usage usually carries the connotation that live data is more fragile and must not be corrupted, or bad things will happen. So a more appropriate response might be: "Well, make sure it works perfectly before we throw live data at it." The implication here is that record deletion is something pretty significant, and a haywire record-deleter running amok live would probably cause great harm.

Node:live data, Next:Live Free Or Die!, Previous:live, Up:= L =

live data n.