The Jargon File by Eric S. Raymond (sites to read books for free .TXT) 📖

Next:[7872]leak, Previous:[7873]LDB, Up:[7874]= 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

[7875]backbone site, [7876]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:[7877]leaky heap, Previous:[7878]leaf site, Up:[7879]=

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. [7880]memory

leak and [7881]fd leak have their own entries; one might also refer,

to, say, a `window handle leak' in a window system.

Node:leaky heap, Next:[7882]leapfrog attack, Previous:[7883]leak,

Up:[7884]= L =

leaky heap n.

[Cambridge] An [7885]arena with a [7886]memory leak.

Node:leapfrog attack, Next:[7887]leech, Previous:[7888]leaky heap,

Up:[7889]= 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:[7890]leech mode, Previous:[7891]leapfrog attack,

Up:[7892]= L =

leech

n. (Also `leecher'.) Among BBS types, crackers and [7893]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 [7894]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:[7895]legal, Previous:[7896]leech, Up:[7897]= 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

[7898]ratio site, [7899]banner site.

Node:legal, Next:[7900]legalese, Previous:[7901]leech mode, Up:[7902]=

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 [7903]language lawyer, [7904]legalese.

Node:legalese, Next:[7905]LER, Previous:[7906]legal, Up:[7907]= L =

legalese n.

Dense, pedantic verbiage in a language description, product

specification, or interface standard; text that seems designed to

obfuscate and requires a [7908]language lawyer to [7909]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, [7910]suits, and situations in which hackers generally get

the short end of the stick.

Node:LER, Next:[7911]LERP, Previous:[7912]legalese, Up:[7913]= 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 [7914]SED. 2. An incandescent light bulb (the filament emits

light because it's resistively heated).

Node:LERP, Next:[7915]let the smoke out, Previous:[7916]LER,

Up:[7917]= 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:[7918]letterbomb, Previous:[7919]LERP,

Up:[7920]= L =

let the smoke out v.

To fry hardware (see [7921]fried). See [7922]magic smoke for a

discussion of the underlying mythology.

Node:letterbomb, Next:[7923]lexer, Previous:[7924]let the smoke out,

Up:[7925]= L =

letterbomb

n. A piece of [7926]email containing [7927]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 [7928]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

[7929]Trojan horse; compare [7930]nastygram. 2. Loosely, a

[7931]mailbomb.

Node:lexer, Next:[7932]lexiphage, Previous:[7933]letterbomb,

Up:[7934]= 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:[7935]life, Previous:[7936]lexer, Up:[7937]= L =

lexiphage /lek'si-fayj`/ n.

A notorious word [7938]chomper on ITS. See [7939]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:[7940]Life is hard, Previous:[7941]lexiphage,

Up:[7942]= L =

life n.

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 [7943]TECO!; see [7944]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.

The opposite of [7945]Usenet. As in "[7946]Get a life!"

Node:Life is hard, Next:[7947]light pipe, Previous:[7948]life,

Up:[7949]= 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:[7950]lightweight, Previous:[7951]Life is hard,

Up:[7952]= L =

light pipe n.

Fiber optic cable. Oppose [7953]copper.

Node:lightweight, Next:[7954]like kicking dead whales down the beach,

Previous:[7955]light pipe, Up:[7956]= L =

lightweight adj.

Opposite of [7957]heavyweight; usually found in combining forms such

as `lightweight process'.

Node:like kicking dead whales down the beach, Next:[7958]like nailing

jelly to a tree, Previous:[7959]lightweight, Up:[7960]= 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

[7961]fear and loathing.

Node:like nailing jelly to a tree, Next:[7962]line 666,

Previous:[7963]like kicking dead whales down the beach, Up:[7964]= 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:[7965]line eater the, Previous:[7966]like nailing

jelly to a tree, Up:[7967]= 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:[7968]line noise, Previous:[7969]line 666,

Up:[7970]= 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 ofline

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 [7971]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

[7972]NSA line eater.

Node:line noise, Next:[7973]line starve, Previous:[7974]line eater

the, Up:[7975]= L =

line noise n.

[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, [7976]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 [7977]TECO; it is often claimed that "TECO's input syntax

is indistinguishable from line noise." Other non-[7978]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 [7979]INTERCAL.

Node:line starve, Next:[7980]linearithmic, Previous:[7981]line noise,

Up:[7982]= 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 theX', and the line feed

gets back to the original line.) 2. n. A character (or character

sequence) that causes a