Chapter L (2)

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

:twilight zone: [IRC] n. Notionally, the area of cyberspace where {IRC}
operators live. An {op} is said to have a "connection to the
twilight zone".

:twink: /twink/ [UCSC] n. Equivalent to {read-only user}.
Also reported on the USENET group soc.motss; may derive from
gay slang for a cute young thing with nothing upstairs (compare
mainstream `chick').

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

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

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

= U = =====

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

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

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

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

:undocumented feature: n. See {feature}.

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

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

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

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

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

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

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

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

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

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

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

:unswizzle: v. See {swizzle}.

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

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

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

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

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

:urchin: n. See {munchkin}.

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

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

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

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

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

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

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

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

= V = =====

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

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

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

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

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

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

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

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

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

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

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

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

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

2. The assumption that characters are signed.

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

= W = =====