= S =

S/N Ratio // n. (also `s/n ratio', `s:n ratio'). Syn. signal-to-noise ratio. Often abbreviated `SNR'.

sacred adj. Reserved for the exclusive use of something (an extension of the standard meaning). Often means that anyone may look at the sacred object, but clobbering it will screw whatever it is sacred to. The comment "Register 7 is sacred to the interrupt handler" appearing in a program would be interpreted by a hacker to mean that if any *other* part of the program changes the contents of register 7, dire consequences are likely to ensue.

saga [WPI] n. A cuspy but bogus raving story about N random broken people.

Here is a classic example of the saga form, as told by Guy L. Steele:

Jon L. White (login name JONL) and I (GLS) were office mates at MIT
for many years. One April, we both flew from Boston to California
for a week on research business, to consult face-to-face with some
people at Stanford, particularly our mutual friend Richard P.
Gabriel (RPG; see Gabriel).

RPG picked us up at the San Francisco airport and drove us back to
Palo Alto (going logical south on route 101, parallel to El Camino Bignum). Palo Alto is adjacent to Stanford University and
about 40 miles south of San Francisco. We ate at The Good Earth, a
`health food' restaurant, very popular, the sort whose milkshakes
all contain honey and protein powder. JONL ordered such a shake
--- the waitress claimed the flavor of the day was "lalaberry". I
still have no idea what that might be, but it became a running
joke. It was the color of raspberry, and JONL said it tasted
rather bitter. I ate a better tostada there than I have ever had
in a Mexican restaurant.

After this we went to the local Uncle Gaylord's Old Fashioned Ice
Cream Parlor. They make ice cream fresh daily, in a variety of
intriguing flavors. It's a chain, and they have a slogan: "If you
don't live near an Uncle Gaylord's --- MOVE!" Also, Uncle Gaylord
(a real person) wages a constant battle to force big-name ice cream
makers to print their ingredients on the package (like air and
plastic and other non-natural garbage). JONL and I had first
discovered Uncle Gaylord's the previous August, when we had flown
to a computer-science conference in Berkeley, California, the first
time either of us had been on the West Coast. When not in the
conference sessions, we had spent our time wandering the length of
Telegraph Avenue, which (like Harvard Square in Cambridge) was
lined with picturesque street vendors and interesting little
shops. On that street we discovered Uncle Gaylord's Berkeley
store. The ice cream there was very good. During that August
visit JONL went absolutely bananas (so to speak) over one
particular flavor, ginger honey.

Therefore, after eating at The Good Earth --- indeed, after every
lunch and dinner and before bed during our April visit --- a trip
to Uncle Gaylord's (the one in Palo Alto) was mandatory. We had
arrived on a Wednesday, and by Thursday evening we had been there
at least four times. Each time, JONL would get ginger honey ice
cream, and proclaim to all bystanders that "Ginger was the spice
that drove the Europeans mad! That's why they sought a route to
the East! They used it to preserve their otherwise off-taste
meat." After the third or fourth repetition RPG and I were getting
a little tired of this spiel, and began to paraphrase him: "Wow!
Ginger! The spice that makes rotten meat taste good!" "Say! Why
don't we find some dog that's been run over and sat in the sun for
a week and put some *ginger* on it for dinner?!" "Right! With a
lalaberry shake!" And so on. This failed to faze JONL; he took it
in good humor, as long as we kept returning to Uncle Gaylord's. He
loves ginger honey ice cream.

Now RPG and his then-wife KBT (Kathy Tracy) were putting us up
(putting up with us?) in their home for our visit, so to thank them
JONL and I took them out to a nice French restaurant of their
choosing. I unadventurously chose the filet mignon, and KBT had je
ne sais quoi du jour, but RPG and JONL had lapin (rabbit).
(Waitress: "Oui, we have fresh rabbit, fresh today." RPG: "Well,
JONL, I guess we won't need any *ginger*!")

We finished the meal late, about 11 P.M., which is 2 A.M Boston
time, so JONL and I were rather droopy. But it wasn't yet
midnight. Off to Uncle Gaylord's!

Now the French restaurant was in Redwood City, north of Palo Alto.
In leaving Redwood City, we somehow got onto route 101 going north
instead of south. JONL and I wouldn't have known the difference
had RPG not mentioned it. We still knew very little of the local
geography. I did figure out, however, that we were headed in the
direction of Berkeley, and half-jokingly suggested that we continue
north and go to Uncle Gaylord's in Berkeley.

RPG said "Fine!" and we drove on for a while and talked. I was
drowsy, and JONL actually dropped off to sleep for 5 minutes. When
he awoke, RPG said, "Gee, JONL, you must have slept all the way
over the bridge!", referring to the one spanning San Francisco
Bay. Just then we came to a sign that said "University Avenue". I
mumbled something about working our way over to Telegraph Avenue;
RPG said "Right!" and maneuvered some more. Eventually we pulled
up in front of an Uncle Gaylord's.

Now, I hadn't really been paying attention because I was so sleepy,
and I didn't really understand what was happening until RPG let me
in on it a few moments later, but I was just alert enough to notice
that we had somehow come to the Palo Alto Uncle Gaylord's after
all.

JONL noticed the resemblance to the Palo Alto store, but hadn't
caught on. (The place is lit with red and yellow lights at night,
and looks much different from the way it does in daylight.) He
said, "This isn't the Uncle Gaylord's I went to in Berkeley! It
looked like a barn! But this place looks *just like* the one back
in Palo Alto!"

RPG deadpanned, "Well, this is the one *I* always come to when I'm
in Berkeley. They've got two in San Francisco, too. Remember,
they're a chain."

JONL accepted this bit of wisdom. And he was not totally ignorant
--- he knew perfectly well that University Avenue was in Berkeley,
not far from Telegraph Avenue. What he didn't know was that there
is a completely different University Avenue in Palo Alto.

JONL went up to the counter and asked for ginger honey. The guy at
the counter asked whether JONL would like to taste it first,
evidently their standard procedure with that flavor, as not too
many people like it.

JONL said, "I'm sure I like it. Just give me a cone." The guy
behind the counter insisted that JONL try just a taste first.
"Some people think it tastes like soap." JONL insisted, "Look, I
*love* ginger. I eat Chinese food. I eat raw ginger roots. I
already went through this hassle with the guy back in Palo Alto. I
*know* I like that flavor!"

At the words "back in Palo Alto" the guy behind the counter got a
very strange look on his face, but said nothing. KBT caught his
eye and winked. Through my stupor I still hadn't quite grasped
what was going on, and thought RPG was rolling on the floor
laughing and clutching his stomach just because JONL had launched
into his spiel ("makes rotten meat a dish for princes") for the
forty-third time. At this point, RPG clued me in fully.

RPG, KBT, and I retreated to a table, trying to stifle our
chuckles. JONL remained at the counter, talking about ice cream
with the guy b.t.c., comparing Uncle Gaylord's to other ice cream
shops and generally having a good old time.

At length the g.b.t.c. said, "How's the ginger honey?" JONL said,
"Fine! I wonder what exactly is in it?" Now Uncle Gaylord
publishes all his recipes and even teaches classes on how to make
his ice cream at home. So the g.b.t.c. got out the recipe, and he
and JONL pored over it for a while. But the g.b.t.c. could contain
his curiosity no longer, and asked again, "You really like that
stuff, huh?" JONL said, "Yeah, I've been eating it constantly back
in Palo Alto for the past two days. In fact, I think this batch is
about as good as the cones I got back in Palo Alto!"

G.b.t.c. looked him straight in the eye and said, "You're *in* Palo
Alto!"

JONL turned slowly around, and saw the three of us collapse in a
fit of giggles. He clapped a hand to his forehead and exclaimed,
"I've been hacked!"

[My spies on the West Coast inform me that there is a close relative of the raspberry found out there called an `ollalieberry' --- ESR]

[Ironic footnote: it appears that the meme about ginger vs. rotting meat may be an urban legend. It's not borne out by an examination of medieval recipes or period purchase records for spices, and appears full-blown in the works of Samuel Pegge, a gourmand and notorious flake case who originated numerous food myths. --- ESR]

sagan /say'gn/ [from Carl Sagan's TV series "Cosmos"; think "billions and billions"] n. A large quantity of anything. "There's a sagan different ways to tweak EMACS." "The U.S. Government spends sagans on bombs and welfare --- hard to say which is more destructive."

SAIL /sayl/, not /S-A-I-L/ n.

The Stanford Artificial Intelligence Lab. An important site in the early development of LISP; with the MIT AI Lab, BBN, CMU, XEROX PARC, and the UNIX community, one of the major wellsprings of technical innovation and hacker-culture traditions (see the WAITS entry for details). The SAIL machines were shut down in late May 1990, scant weeks after the MIT AI Lab's ITS cluster was officially decommissioned.
The Stanford Artificial Intelligence Language used at SAIL (sense 1). It was an Algol-60 derivative with a coroutining facility and some new data types intended for building search trees and association lists.

salescritter /sayls'kri`tr/ n. Pejorative hackerism for a computer salesperson. Hackers tell the following joke:

     Q. What's the difference between a used-car dealer and a
        computer salesman?
     A. The used-car dealer knows he's lying.  [Some versions add:
        ...and probably knows how to drive.]

This reflects the widespread hacker belief that salescritters are self-selected for stupidity (after all, if they had brains and the inclination to use them, they'd be in programming). The terms `salesthing' and `salesdroid' are also common. Compare marketroid, suit, droid.

salt n. A tiny bit of near-random data inserted where too much regularity would be undesirable; a data frob (sense 1). For example, the Unix crypt(3) man page mentions that "the salt string is used to perturb the DES algorithm in one of 4096 different ways."

salt mines n. Dense quarters housing large numbers of programmers working long hours on grungy projects, with some hope of seeing the end of the tunnel in N years. Noted for their absence of sunshine. Compare playpen, sandbox.

salt substrate [MIT] n. Collective noun used to refer to potato chips, pretzels, saltines, or any other form of snack food designed primarily as a carrier for sodium chloride. From the technical term `chip substrate', used to refer to the silicon on the top of which the active parts of integrated circuits are deposited.

same-day service n. Ironic term used to describe long response time, particularly with respect to MS-DOS system calls (which ought to require only a tiny fraction of a second to execute). Such response time is a major incentive for programmers to write programs that are not well-behaved. See also PC-Ism.

samizdat [Russian, literally "self publishing"] n. The process of disseminating documentation via underground channels. Originally referred to photocopy duplication and distribution of banned books in the former Soviet Union; now refers by obvious extension to any less-than-official promulgation of textual material, esp. rare, obsolete, or never-formally-published computer documentation. Samizdat is obviously much easier when one has access to high-bandwidth networks and high-quality laser printers. Note that samizdat is properly used only with respect to documents which contain needed information (see also hacker ethic, the) but which are for some reason otherwise unavailable, but *not* in the context of documents which are available through normal channels, for which unauthorized duplication would be unethical copyright violation. See Lions Book for a historical example.

samurai n. A hacker who hires out for legal cracking jobs, snooping for factions in corporate political fights, lawyers pursuing privacy-rights and First Amendment cases, and other parties with legitimate reasons to need an electronic locksmith. In 1991, mainstream media reported the existence of a loose-knit culture of samurai that meets electronically on BBS systems, mostly bright teenagers with personal micros; they have modeled themselves explicitly on the historical samurai of Japan and on the "net cowboys" of William Gibson's cyberpunk novels. Those interviewed claim to adhere to a rigid ethic of loyalty to their employers and to disdain the vandalism and theft practiced by criminal crackers as beneath them and contrary to the hacker ethic; some quote Miyamoto Musashi's "Book of Five Rings", a classic of historical samurai doctrine, in support of these principles. See also Stupids, social engineering, cracker, hacker ethic, the, and dark-side hacker.

sandbender [IBM] n. A person involved with silicon lithography and the physical design of chips. Compare ironmonger, polygon pusher.

sandbox n.

(also `sandbox, the') Common term for the R&D department at many software and computer companies (where hackers in commercial environments are likely to be found). Half-derisive, but reflects the truth that research is a form of creative play. Compare playpen.
Syn. link farm.

sanity check n.

The act of checking a piece of code (or anything else, e.g., a USENET posting) for completely stupid mistakes. Implies that the check is to make sure the author was sane when it was written; e.g., if a piece of scientific software relied on a particular formula and was giving unexpected results, one might first look at the nesting of parentheses or the coding of the formula, as a `sanity check', before looking at the more complex I/O or data structure manipulation routines, much less the algorithm itself. Compare reality check.
A run-time test, either validating input or ensuring that the program hasn't screwed up internally (producing an inconsistent value or state).

Saturday-night special [from police slang for a cheap handgun] n. A quick-and-dirty program or feature kluged together during off hours, under a deadline, and in response to pressure from a salescritter. Such hacks are dangerously unreliable, but all too often sneak into a production release after insufficient review.

say vt.

To type to a terminal. "To list a directory verbosely, you have to say `ls -l'." Tends to imply a newline-terminated command (a `sentence').
A computer may also be said to `say' things to you, even if it doesn't have a speech synthesizer, by displaying them on a terminal in response to your commands. Hackers find it odd that this usage confuses mundanes.

scag vt. To destroy the data on a disk, either by corrupting the filesystem or by causing media damage. "That last power hit scagged the system disk." Compare scrog, roach.

scanno /skan'oh/ n. An error in a document caused by a scanner glitch, analogous to a typo or thinko.

schroedinbug /shroh'din-buhg/ [MIT: from the Schroedinger's Cat thought-experiment in quantum physics] n. A design or implementation bug in a program that doesn't manifest until someone reading source or using the program in an unusual way notices that it never should have worked, at which point the program promptly stops working for everybody until fixed. Though (like bit rot) this sounds impossible, it happens; some programs have harbored latent schroedinbugs for years. Compare heisenbug, Bohr Bug, mandelbug.

science-fiction fandom n. Another voluntary subculture having a very heavy overlap with hackerdom; most hackers read SF and/or fantasy fiction avidly, and many go to `cons' (SF conventions) or are involved in fandom-connected activities such as the Society for Creative Anachronism. Some hacker jargon originated in SF fandom; see defenestration, great-wall, cyberpunk, h, ha ha only serious, IMHO, mundane, neep-neep, Real Soon Now. Additionally, the jargon terms cowboy, cyberspace, de-rezz, go flatline, ice, phage, virus, wetware, wirehead, and worm originated in SF stories.

scram switch [from the nuclear power industry] n. An emergency-power-off switch (see Big Red Switch), esp. one positioned to be easily hit by evacuating personnel. In general, this is *not* something you frob lightly; these often initiate expensive events (such as Halon dumps) and are installed in a dinosaur pen for use in case of electrical fire or in case some luckless field servoid should put 120 volts across himself while Easter Egging. (See also molly-guard, TMRC.)

scratch

[from `scratchpad'] adj. Describes a data structure or recording medium attached to a machine for testing or temporary-use purposes; one that can be scribbled on without loss. Usually in the combining forms `scratch memory', `scratch register', `scratch disk', `scratch tape', `scratch volume'. See also scratch monkey.
[primarily IBM] vt. To delete (as in a file).

scratch monkey n. As in "Before testing or reconfiguring, always mount a scratch monkey", a proverb used to advise caution when dealing with irreplaceable data or devices. Used to refer to any scratch volume hooked to a computer during any risky operation as a replacement for some precious resource or data that might otherwise get trashed.

This term preserves the memory of Mabel, the Swimming Wonder Monkey, star of a biological research program at the University of Toronto. Mabel was not (so the legend goes) your ordinary monkey; the university had spent years teaching her how to swim, breathing through a regulator, in order to study the effects of different gas mixtures on her physiology. Mabel suffered an untimely demise one day when a DEC engineer troubleshooting a crash on the program's VAX inadvertently interfered with some custom hardware that was wired to Mabel.

It is reported that, after calming down an understandably irate customer sufficiently to ascertain the facts of the matter, a DEC troubleshooter called up the field circus manager responsible and asked him sweetly, "Can you swim?"

Not all the consequences to humans were so amusing; the sysop of the machine in question was nearly thrown in jail at the behest of certain clueless droids at the local `humane' society. The moral is clear: When in doubt, always mount a scratch monkey.

[There is a version of this story, complete with reported dialogue between one of the project people and DEC field service, that has been circulating on Internet since 1986. It is hilarious and mythic, but gets some facts wrong. For example, it reports the machine as a PDP-11 and alleges that Mabel's demise occurred when DEC PMed the machine. Earlier versions of this entry were based on that story; this one has been corrected from an interview with the hapless sysop. --- ESR]

scream and die v. Syn. cough and die, but connotes that an error message was printed or displayed before the program crashed.

screaming tty [UNIX] n. A terminal line which spews an infinite number of random characters at the operating system. This can happen if the terminal is either disconnected or connected to a powered-off terminal but still enabled for login; misconfiguration, misimplementation, or simple bad luck can start such a terminal screaming. A screaming tty or two can seriously degrade the performance of a vanilla UNIX system; the arriving "characters" are treated as userid/password pairs and tested as such. The UNIX password encryption algorithm is designed to be computationally intensive in order to foil brute-force crack attacks, so although none of the logins succeeds; the overhead of rejecting them all can be substantial.

screw [MIT] n. A lose, usually in software. Especially used for user-visible misbehavior caused by a bug or misfeature. This use has become quite widespread outside MIT.

screwage /skroo'*j/ n. Like lossage but connotes that the failure is due to a designed-in misfeature rather than a simple inadequacy or a mere bug.

scribble n. To modify a data structure in a random and unintentionally destructive way. "Bletch! Somebody's disk-compactor program went berserk and scribbled on the i-node table." "It was working fine until one of the allocation routines scribbled on low core." Synonymous with trash; compare mung, which conveys a bit more intention, and mangle, which is more violent and final.

scrog /skrog/ [Bell Labs] vt. To damage, trash, or corrupt a data structure. "The list header got scrogged." Also reported as `skrog', and ascribed to the comic strip "The Wizard of Id". Compare scag; possibly the two are related. Equivalent to scribble or mangle.

scrool /skrool/ [from the pioneering Roundtable chat system in Houston ca. 1984; prob. originated as a typo for `scroll'] n. The log of old messages, available for later perusal or to help one get back in synch with the conversation. It was originally called the `scrool monster', because an early version of the roundtable software had a bug where it would dump all 8K of scrool on a user's terminal.

scrozzle /skroz'l/ vt. Used when a self-modifying code segment runs incorrectly and corrupts the running program or vital data. "The damn compiler scrozzled itself again!"

scruffies n. See neats vs. scruffies.

SCSI [Small Computer System Interface] n. A bus-independent standard for system-level interfacing between a computer and intelligent devices. Typically annotated in literature with `sexy' (/sek'see/), `sissy' (/sis'ee/), and `scuzzy' (/skuh'zee/) as pronunciation guides --- the last being the overwhelmingly predominant form, much to the dismay of the designers and their marketing people. One can usually assume that a person who pronounces it /S-C-S-I/ is clueless.

ScumOS /skuhm'os/ or /skuhm'O-S/ n. Unflattering hackerism for SunOS, the UNIX variant supported on Sun Microsystems's UNIX workstations (see also sun-stools), and compare AIDX, Macintrash, Nominal Semidestructor, Open DeathTrap, HP-SUX. Despite what this term might suggest, Sun was founded by hackers and still enjoys excellent relations with hackerdom; usage is more often in exasperation than outright loathing.

search-and-destroy mode n. Hackerism for a noninteractive search-and-replace facility in an editor, so called because an incautiously chosen match pattern can cause infinite damage.

second-system effect n. (sometimes, more euphoniously, `second-system syndrome') When one is designing the successor to a relatively small, elegant, and successful system, there is a tendency to become grandiose in one's success and design an elephantine feature-laden monstrosity. The term was first used by Fred Brooks in his classic "The Mythical Man-Month: Essays on Software Engineering" (Addison-Wesley, 1975; ISBN 0-201-00650-2). It described the jump from a set of nice, simple operating systems on the IBM 70xx series to OS/360 on the 360 series. A similar effect can also happen in an evolving system; see Brooks'S Law, creeping elegance, creeping featurism. See also Multics, OS/2, X, software bloat.

This version of the jargon lexicon has been described (with altogether too much truth for comfort) as an example of second-system effect run amok on jargon-1....

secondary damage n. When a fatal error occurs (esp. a segfault) the immediate cause may be that a pointer has been trashed due to a previous fandango on core. However, this fandango may have been due to an *earlier* fandango, so no amount of analysis will reveal (directly) how the damage occurred. "The data structure was clobbered, but it was secondary damage."

By extension, the corruption resulting from N cascaded fandangoes on core is `Nth-level damage'. There is at least one case on record in which 17 hours of grovelling with `adb' actually dug up the underlying bug behind an instance of seventh-level damage! The hacker who accomplished this near-superhuman feat was presented with an award by his fellows.

security through obscurity alt. `security by obscurity' n. A term applied by hackers to most OS vendors' favorite way of coping with security holes --- namely, ignoring them, documenting neither any known holes nor the underlying security algorithms, trusting that nobody will find out about them and that people who do find out about them won't exploit them. This "strategy" never works for long and occasionally sets the world up for debacles like the RTM worm of 1988 (see Great Worm, The), but once the brief moments of panic created by such events subside most vendors are all too willing to turn over and go back to sleep. After all, actually fixing the bugs would siphon off the resources needed to implement the next user-interface frill on marketing's wish list --- and besides, if they started fixing security bugs customers might begin to *expect* it and imagine that their warranties of merchantability gave them some sort of *right* to a system with fewer holes in it than a shotgunned Swiss cheese, and *then* where would we be?

Historical note: There are conflicting stories about the origin of this term. It has been claimed that it was first used in the USENET newsgroup in comp.sys.apollo during a campaign to get HP/Apollo to fix security problems in its UNIX-clone Aegis/DomainOS (they didn't change a thing). ITS fans, on the other hand, say it was coined years earlier in opposition to the incredibly paranoid Multics people down the hall, for whom security was everything. In the ITS culture it referred to (1) the fact that that by the time a tourist figured out how to make trouble he'd generally gotten over the urge to make it, because he felt part of the community; and (2) (self-mockingly) the poor coverage of the documentation and obscurity of many commands. One instance of *deliberate* security through obscurity is recorded; the command to allow patching the running ITS system (altmode altmode control-R) echoed as $$^D. If you actually typed alt alt ^D, that set a flag that would prevent patching the system even if you later got it right.

SED [TMRC, from `Light-Emitting Diode'] /S-E-D/ n. Smoke-emitting diode. A friode that lost the war. See also LER.

segfault n.,vi. Syn. segment, segmentation fault.

seggie /seg'ee/ [UNIX] n. Shorthand for segmentation fault reported from Britain.

segment /seg'ment/ vi. To experience a segmentation fault. Confusingly, this is often pronounced more like the noun `segment' than like mainstream v. segment; this is because it is actually a noun shorthand that has been verbed.

segmentation fault n. [UNIX]

An error in which a running program attempts to access memory not allocated to it and core dumps with a segmentation violation error.
To lose a train of thought or a line of reasoning. Also uttered as an exclamation at the point of befuddlement.

segv /seg'vee/ n.,vi. Yet another synonym for segmentation fault (actually, in this case, `segmentation violation').

self-reference n. See self-reference.

selvage /sel'v*j/ [from sewing and weaving] n. See chad (sense 1).

semi /se'mee/ or /se'mi:/

n. Abbreviation for `semicolon', when speaking. "Commands to grind are prefixed by semi-semi-star" means that the prefix is `;;*', not 1/4 of a star.
A prefix used with words such as `immediately' as a qualifier. "When is the system coming up?" "Semi-immediately." (That is, maybe not for an hour.) "We did consider that possibility semi-seriously." See also infinite.

semi-infinite n. See infinite.

senior bit [IBM] n. Syn. meta bit.

server n. A kind of daemon that performs a service for the requester and which often runs on a computer other than the one on which the server runs. A particularly common term on the Internet, which is rife with `name servers', `domain servers', `news servers', `finger servers', and the like.

SEX /seks/ [Sun Users' Group & elsewhere] n.

Software EXchange. A technique invented by the blue-green algae hundreds of millions of years ago to speed up their evolution, which had been terribly slow up until then. Today, SEX parties are popular among hackers and others (of course, these are no longer limited to exchanges of genetic software). In general, SEX parties are a Good Thing, but unprotected SEX can propagate a virus. See also pubic directory.
The rather Freudian mnemonic often used for Sign EXtend, a machine instruction found in the PDP-11 and many other architectures. The RCA 1802 chip used in the early Elf and SuperElf personal computers had a `SEt X register' SEX instruction, but this seems to have had little folkloric impact.

DEC's engineers nearly got a PDP-11 assembler that used the `SEX' mnemonic out the door at one time, but (for once) marketing wasn't asleep and forced a change. That wasn't the last time this happened, either. The author of "The Intel 8086 Primer", who was one of the original designers of the 8086, noted that there was originally a `SEX' instruction on that processor, too. He says that Intel management got cold feet and decreed that it be changed, and thus the instruction was renamed `CBW' and `CWD' (depending on what was being extended). Amusingly, the Intel 8048 (the microcontroller used in IBM PC keyboards) is also missing straight `SEX' but has logical-or and logical-and instructions `ORL' and `ANL'.

The Motorola 6809, used in the U.K.'s `Dragon 32' personal computer, actually had an official `SEX' instruction; the 6502 in the Apple II with which it competed did not. British hackers thought this made perfect mythic sense; after all, it was commonly observed, you could (on some theoretical level) have sex with a dragon, but you can't have sex with an apple.

sex changer n. Syn. gender mender.

shambolic link /sham-bol'ik link/ n. A UNIX symbolic link, particularly when it confuses you, points to nothing at all, or results in your ending up in some completely unexpected part of the filesystem....

sharchive /shar'ki:v/ [UNIX and USENET; from /bin/sh archive] n. A flattened representation of a set of one or more files, with the unique property that it can be unflattened (the original files restored) by feeding it through a standard UNIX shell; thus, a sharchive can be distributed to anyone running UNIX, and no special unpacking software is required. Sharchives are also intriguing in that they are typically created by shell scripts; the script that produces sharchives is thus a script which produces self-unpacking scripts, which may themselves contain scripts. (The downsides of sharchives are that they are an ideal venue for Trojan Horse attacks and that, for recipients not running UNIX, no simple un-sharchiving program is possible; sharchives can and do make use of arbitrarily-powerful shell features.) Sharchives are also commonly referred to as `shar files' after the name of the most common program for generating them.

Share And Enjoy! imp.

Commonly found at the end of software release announcements and README Files, this phrase indicates allegiance to the hacker ethic of free information sharing (see hacker ethic, the, sense 1).
The motto of the Sirius Cybernetics Corporation (the ultimate gaggle of incompetent suits) in Douglas Adams's "Hitch Hiker's Guide to the Galaxy". The irony of using this as a cultural recognition signal appeals to freeware hackers.

shareware /sheir'weir/ n. Freeware (sense 1) for which the author requests some payment, usually in the accompanying documentation files or in an announcement made by the software itself. Such payment may or may not buy additional support or functionality. See also careware, charityware, crippleware, guiltware, postcardware, and -ware; compare payware.

shelfware /shelfweir/ n. Software purchased on a whim (by an individual user) or in accordance with policy (by a corporation or government agency), but not actually required for any particular use. Therefore, it often ends up on some shelf.

shell [orig. Multics techspeak, widely propagated via UNIX] n.

[techspeak] The command interpreter used to pass commands to an operating system; so called because it is the part of the operating system that interfaces with the outside world.
More generally, any interface program that mediates access to a special resource or server for convenience, efficiency, or security reasons; for this meaning, the usage is usually `a shell around' whatever. This sort of program is also called a `wrapper'.

shell out [UNIX] n. To spawn an interactive subshell from within a program (e.g., a mailer or editor). "Bang foo runs foo in a subshell, while bang alone shells out."

shift left (or right) logical [from any of various machines' instruction sets]

vi. To move oneself to the left (right). To move out of the way.

imper. "Get out of that (my) seat! You can shift to that empty one to the left (right)." Often used without the `logical', or as `left shift' instead of `shift left'. Sometimes heard as LSH /lish/, from the PDP-10 instruction set. See Programmer'S Cheer.

shim n. A small piece of data inserted in order to achieve a desired memory alignment or other addressing property. For example, the PDP-11 UNIX linker, in split I&D (instructions and data) mode, inserts a two-byte shim at location 0 in data space so that no data object will have an address of 0 (and be confused with the C null pointer). See also loose bytes.

shitogram /shit'oh-gram/ n. A *really* nasty piece of email. Compare nastygram, flame.

short card n. A half-length IBM PC expansion card or adapter that will fit in one of the two short slots located towards the right rear of a standard chassis (tucked behind the floppy disk drives). See also tall card.

shotgun debugging n. The software equivalent of Easter Egging; the making of relatively undirected changes to software in the hope that a bug will be perturbed out of existence. This almost never works, and usually introduces more bugs.

shovelware /shuh'v*l-weir`/ n. Extra software dumped onto a CD-ROM or tape to fill up the remaining space on the medium after the software distribution it's intended to carry, but not integrated with the distribution.

showstopper n. A hardware or (especially) software bug that makes an implementation effectively unusable; one that absolutely has to be fixed before development can go on. Opposite in connotation from its original theatrical use, which refers to something stunningly *good*.

shriek n. See excl. Occasional CMU usage, also in common use among APL fans and mathematicians, especially category theorists.

Shub-Internet /shuhb in't*r-net/ [MUD: from H. P. Lovecraft's evil fictional deity `Shub-Niggurath', the Black Goat with a Thousand Young] n. The harsh personification of the Internet, Beast of a Thousand Processes, Eater of Characters, Avatar of Line Noise, and Imp of Call Waiting; the hideous multi-tendriled entity formed of all the manifold connections of the net. A sect of MUDders worships Shub-Internet, sacrificing objects and praying for good connections. To no avail --- its purpose is malign and evil, and is the cause of all network slowdown. Often heard as in "Freela casts a tac nuke at Shub-Internet for slowing her down." (A forged response often follows along the lines of: "Shub-Internet gulps down the tac nuke and burps happily.") Also cursed by users of FTP and telnet when the system slows down. The dread name of Shub-Internet is seldom spoken aloud, as it is said that repeating it three times will cause the being to wake, deep within its lair beneath the Pentagon.

sidecar n.

Syn. slap on the side. Esp. used of add-ons for the late and unlamented IBM PCjr.
The IBM PC compatibility box that could be bolted onto the side of an Amiga. Designed and produced by Commodore, it broke all of the company's own design rules. If it worked with any other peripherals, it was by magic.

SIG /sig/ n. (also common as a prefix in combining forms) A Special Interest Group, in one of several technical areas, sponsored by the Association for Computing Machinery; well-known ones include SIGPLAN (the Special Interest Group on Programming Languages), SIGARCH (the Special Interest Group for Computer Architecture) and SIGGRAPH (the Special Interest Group for Computer Graphics). Hackers, not surprisingly, like to overextend this naming convention to less formal associations like SIGBEER (at ACM conferences) and SIGFOOD (at University of Illinois).

sig block /sig blok/ [UNIX; often written `.sig' there] n. Short for `signature', used specifically to refer to the electronic signature block that most UNIX mail- and news-posting software will automagically append to outgoing mail and news. The composition of one's sig can be quite an art form, including an ASCII logo or one's choice of witty sayings (see sig quote, fool file, the); but many consider large sigs a waste of bandwidth, and it has been observed that the size of one's sig block is usually inversely proportional to one's longevity and level of prestige on the net. See also doubled sig.

sig quote /sig kwoht/ [USENET] n. A maxim, quote, proverb, joke, or slogan embedded in one's sig block and intended to convey something of one's philosophical stance, pet peeves, or sense of humor. "Calm down, it's only ones and zeroes."

sig virus n. A parasitic meme embedded in a sig block. There was a meme plague or fad for these on USENET in late 1991. Most were equivalents of "I am a .sig virus. Please reproduce me in your .sig block.". Of course, the .sig virus's memetic hook is the giggle value of going along with the gag; this, however, was a self-limiting phenomenon as more and more people picked up on the idea. There were creative variants on it; some people stuck `sig virus antibody' texts in their sigs, and there was at least one instance of a sig virus eater.

signal-to-noise ratio [from analog electronics] n. Used by hackers in a generalization of its technical meaning. `Signal' refers to useful information conveyed by some communications medium, and `noise' to anything else on that medium. Hence a low ratio implies that it is not worth paying attention to the medium in question. Figures for such metaphorical ratios are never given. The term is most often applied to USENET newsgroups during flame wars. Compare bandwidth. See also Coefficient Of X, lost in the noise.

silicon n. Hardware, esp. ICs or microprocessor-based computer systems (compare iron). Contrasted with software. See also sandbender.

silly walk [from Monty Python's Flying Circus] vi.

A ridiculous procedure required to accomplish a task. Like grovel, but more random and humorous. "I had to silly-walk through half the /usr directories to find the maps file."
Syn. fandango on core.

silo n. The FIFO input-character buffer in an RS-232 line card. So called from DEC terminology used on DH and DZ line cards for the VAX and PDP-11, presumably because it was a storage space for fungible stuff that went in at the top and came out at the bottom.

Silver Book n. Jensen and Wirth's infamous "Pascal User Manual and Report", so called because of the silver cover of the widely distributed Springer-Verlag second edition of 1978 (ISBN 0-387-90144-2). See book titles, Pascal.

since time T equals minus infinity adv. A long time ago; for as long as anyone can remember; at the time that some particular frob was first designed. Usually the word `time' is omitted. See also Time T; contrast epoch.

sitename /si:t'naym/ [UNIX/Internet] n. The unique electronic name of a computer system, used to identify it in UUCP mail, USENET, or other forms of electronic information interchange. The folklore interest of sitenames stems from the creativity and humor they often display. Interpreting a sitename is not unlike interpreting a vanity license plate; one has to mentally unpack it, allowing for mono-case and length restrictions and the lack of whitespace. Hacker tradition deprecates dull, institutional-sounding names in favor of punchy, humorous, and clever coinages (except that it is considered appropriate for the official public gateway machine of an organization to bear the organization's name or acronym). Mythological references, cartoon characters, animal names, and allusions to SF or fantasy literature are probably the most popular sources for sitenames (in roughly descending order). The obligatory comment when discussing these is Harris's Lament: "All the good ones are taken!" See also network address.

skrog v. Syn. scrog.

skulker n. Syn. prowler.

slack n.

Space allocated to a disk file but not actually used to store useful information. The techspeak equivalent is `internal fragmentation'.
In the theology of the Church Of The SubGenius, a mystical substance or quality that is the prerequisite of all human happiness.

Since UNIX files are stored compactly, except for the unavoidable wastage in the last block or fragment, it might be said that "Unix has no slack". See ha ha only serious.

slap on the side n. (also called a sidecar, or abbreviated `SOTS'.) A type of external expansion hardware marketed by computer manufacturers (e.g., Commodore for the Amiga 500/1000 series and IBM for the hideous failure called `PCjr'). Various SOTS boxes provided necessities such as memory, hard drive controllers, and conventional expansion slots.

slash n. Common name for the slant (`/', ASCII 0101111) character. See ASCII for other synonyms.

sleep vi.

[techspeak] To relinquish a claim (of a process on a multitasking system) for service; to indicate to the scheduler that a process may be deactivated until some given event occurs or a specified time delay elapses.
In jargon, used very similarly to v. block; also in `sleep on', syn. with `block on'. Often used to indicate that the speaker has relinquished a demand for resources until some (possibly unspecified) external event: "They can't get the fix I've been asking for into the next release, so I'm going to sleep on it until the release, then start hassling them again."

slim n. A small, derivative change (e.g., to code).

slop n.

A one-sided fudge factor, that is, an allowance for error but in only one of two directions. For example, if you need a piece of wire 10 feet long and have to guess when you cut it, you make very sure to cut it too long, by a large amount if necessary, rather than too short by even a little bit, because you can always cut off the slop but you can't paste it back on again. When discrete quantities are involved, slop is often introduced to avoid the possibility of being on the losing side of a fencepost error.
The percentage of `extra' code generated by a compiler over the size of equivalent assembler code produced by hand-hacking; i.e., the space (or maybe time) you lose because you didn't do it yourself. This number is often used as a measure of the goodness of a compiler; slop below 5% is very good, and 10% is usually acceptable. With modern compiler technology, esp. on RISC machines, the compiler's slop may actually be *negative*; that is, humans may be unable to generate code as good. This is one of the reasons assembler programming is no longer common.

slopsucker /slop'suhk-r/ n. A lowest-priority task that waits around until everything else has `had its fill' of machine resources. Only when the machine would otherwise be idle is the task allowed to `suck up the slop'. Also called a `hungry puppy' or `bottom feeder'. One common variety of slopsucker hunts for large prime numbers. Compare background.

slurp vt. To read a large data file entirely into core before working on it. This may be contrasted with the strategy of reading a small piece at a time, processing it, and then reading the next piece. "This program slurps in a 1K-by-1K matrix and does an FFT." See also sponge.

smart adj. Said of a program that does the Right Thing in a wide variety of complicated circumstances. There is a difference between calling a program smart and calling it intelligent; in particular, there do not exist any intelligent programs (yet --- see AI-Complete). Compare robust (smart programs can be brittle).

smart terminal n.

A terminal that has enough computing capability to render graphics or to offload some kind of front-end processing from the computer it talks to. The development of workstations and personal computers has made this term and the product it describes semi-obsolescent, but one may still hear variants of the phrase `act like a smart terminal' used to describe the behavior of workstations or PCs with respect to programs that execute almost entirely out of a remote server's storage, using said devices as displays.
obs. Any terminal with an addressable cursor; the opposite of a glass tty. Today, a terminal with merely an addressable cursor, but with none of the more-powerful features mentioned in sense 1, is called a dumb terminal.

There is a classic quote from Rob Pike (inventor of the blit terminal): "A smart terminal is not a smart*ass* terminal, but rather a terminal you can educate." This illustrates a common design problem: The attempt to make peripherals (or anything else) intelligent sometimes results in finicky, rigid `special features' that become just so much dead weight if you try to use the device in any way the designer didn't anticipate. Flexibility and programmability, on the other hand, are *really* smart. Compare hook.

smash case vi. To lose or obliterate the uppercase/lowercase distinction in text input. "MS-DOS will automatically smash case in the names of all the files you create." Compare fold case.

smash the stack [C programming] n. To corrupt the execution stack by writing past the end of a local array or other data structure. Code that smashes the stack can cause a return from the routine to jump to a random address, resulting in some of the most insidious data-dependent bugs known to mankind. Variants include `trash' the stack, scribble the stack, mangle the stack; the term **mung the stack is not used, as this is never done intentionally. See spam; see also aliasing bug, fandango on core, memory leak, memory smash, precedence lossage, overrun screw.

smiley n. See emoticon.

smoke vi.

crash or blow up, usually spectacularly. "The new version smoked, just like the last one." Used for both hardware (where it often describes an actual physical event), and software (where it's merely colorful).
[from automotive slang] To be conspicuously fast. "That processor really smokes." Compare magic smoke.

smoke and mirrors n. Marketing deceptions. The term is mainstream in this general sense. Among hackers it's strongly associated with bogus demos and crocked benchmarks (see also MIPS, machoflops). "They claim their new box cranks 50 MIPS for under $5000, but didn't specify the instruction mix --- sounds like smoke and mirrors to me." The phrase has been said to derive from carnie slang for magic acts and `freak show' displays that depend on `trompe l'oeil' effects, but also calls to mind the fierce Aztec god Tezcatlipoca (lit. "Smoking Mirror") for whom the hearts of huge numbers of human sacrificial victims were regularly cut out. Upon hearing about a rigged demo or yet another round of fantasy-based marketing promises, hackers often feel analogously disheartened.

smoke test n.

A rudimentary form of testing applied to electronic equipment following repair or reconfiguration, in which power is applied and the tester checks for sparks, smoke, or other dramatic signs of fundamental failure. See magic smoke.
By extension, the first run of a piece of software after construction or a critical change. See and compare reality check.

There is an interesting semi-parallel to this term among typographers and printers: When new typefaces are being punch-cut by hand, a `smoke test' (hold the letter in candle smoke, then press it onto paper) is used to check out new dies.

smoking clover [ITS] n. A display hack originally due to Bill Gosper. Many convergent lines are drawn on a color monitor in AOS mode (so that every pixel struck has its color incremented). The lines all have one endpoint in the middle of the screen; the other endpoints are spaced one pixel apart around the perimeter of a large square. The color map is then repeatedly rotated. This results in a striking, rainbow-hued, shimmering four-leaf clover. Gosper joked about keeping it hidden from the FDA (the U.S.'s Food and Drug Administration) lest its hallucinogenic properties cause it to be banned.

SMOP /S-M-O-P/ [Simple (or Small) Matter of Programming] n.

A piece of code, not yet written, whose anticipated length is significantly greater than its complexity. Used to refer to a program that could obviously be written, but is not worth the trouble. Also used ironically to imply that a difficult problem can be easily solved because a program can be written to do it; the irony is that it is very clear that writing such a program will be a great deal of work. "It's easy to enhance a FORTRAN compiler to compile COBOL as well; it's just an SMOP."
Often used ironically by the intended victim when a suggestion for a program is made which seems easy to the suggester, but is obviously (to the victim) a lot of work.

smurf /smerf/ [from the soc.motss newsgroup on USENET, after some obnoxiously gooey cartoon characters] n. A newsgroup regular with a habitual style that is irreverent, silly, and cute. Like many other hackish terms for people, this one may be praise or insult depending on who uses it. In general, being referred to as a smurf is probably not going to make your day unless you've previously adopted the label yourself in a spirit of irony. Compare old fart.

SNAFU principle /sna'foo prin'si-pl/ [from a WWII Army acronym for `Situation Normal, All Fucked Up'] n. "True communication is possible only between equals, because inferiors are more consistently rewarded for telling their superiors pleasant lies than for telling the truth." --- a central tenet of Discordianism, often invoked by hackers to explain why authoritarian hierarchies screw up so reliably and systematically. The effect of the SNAFU principle is a progressive disconnection of decision-makers from reality. This lightly adapted version of a fable dating back to the early 1960s illustrates the phenomenon perfectly:

In the beginning was the plan, and then the specification; And the plan was without form, and the specification was void. And darkness was on the faces of the implementors thereof; And they spake unto their leader, saying: "It is a crock of shit, and smells as of a sewer." And the leader took pity on them, and spoke to the project leader: "It is a crock of excrement, and none may abide the odor thereof." And the project leader spake unto his section head, saying: "It is a container of excrement, and it is very strong, such that none may abide it." The section head then hurried to his department manager, and informed him thus: "It is a vessel of fertilizer, and none may abide its strength." The department manager carried these words to his general manager, and spoke unto him saying: "It containeth that which aideth the growth of plants, and it is very strong." And so it was that the general manager rejoiced and delivered the good news unto the Vice President. "It promoteth growth, and it is very powerful." The Vice President rushed to the President's side, and joyously exclaimed: "This powerful new software product will promote the growth of the company!" And the President looked upon the product, and saw that it was very good. After the subsequent disaster, the suits protect themselves by saying "I was misinformed!", and the implementors are demoted or fired.

snail vt. To snail-mail something. "Snail me a copy of those graphics, will you?"

snail-mail n. Paper mail, as opposed to electronic. Sometimes written as the single word `SnailMail'. One's postal address is, correspondingly, a `snail address'. Derives from earlier coinage `USnail' (from `U.S. Mail'), for which there have even been parody posters and stamps made. Oppose email.

snap v. To replace a pointer to a pointer with a direct pointer; to replace an old address with the forwarding address found there. If you telephone the main number for an institution and ask for a particular person by name, the operator may tell you that person's extension before connecting you, in the hopes that you will `snap your pointer' and dial direct next time. The underlying metaphor may be that of a rubber band stretched through a number of intermediate points; if you remove all the thumbtacks in the middle, it snaps into a straight line from first to last. See chase pointers.

Often, the behavior of a trampoline is to perform an error check once and then snap the pointer that invoked it so as henceforth to bypass the trampoline (and its one-shot error check). In this context one also speaks of `snapping links'. For example, in a LISP implementation, a function interface trampoline might check to make sure that the caller is passing the correct number of arguments; if it is, and if the caller and the callee are both compiled, then snapping the link allows that particular path to use a direct procedure-call instruction with no further overhead.

snarf /snarf/ vt.

To grab, esp. to grab a large document or file for the purpose of using it with or without the author's permission. See also BLT.
[in the UNIX community] To fetch a file or set of files across a network. See also blast. This term was mainstream in the late 1960s, meaning `to eat piggishly'. It may still have this connotation in context. "He's in the snarfing phase of hacking --- FTPing megs of stuff a day."
To acquire, with little concern for legal forms or politesse (but not quite by stealing). "They were giving away samples, so I snarfed a bunch of them."
Syn. for slurp. "This program starts by snarfing the entire database into core, then...."
[GEnie] To spray food or programming fluids due to laughing at the wrong moment. "I was drinking coffee, and when I read your post I snarfed all over my desk." "If I keep reading this topic, I think I'll have to snarf-proof my computer with a keyboard condom." [This sense appears to be widespread among mundane teenagers --- ESR]

snarf & barf /snarf'n-barf`/ n. Under a WIMP Environment, the act of grabbing a region of text and then stuffing the contents of that region into another region (or the same one) to avoid retyping a command line. In the late 1960s, this was a mainstream expression for an `eat now, regret it later' cheap-restaurant expedition.

snarf down v. To snarf, with the connotation of absorbing, processing, or understanding. "I'll snarf down the latest version of the nethack user's guide --- it's been a while since I played last and I don't know what's changed recently."

snark [Lewis Carroll, via the Michigan Terminal System] n.

A system failure. When a user's process bombed, the operator would get the message "Help, Help, Snark in MTS!"
More generally, any kind of unexplained or threatening event on a computer (especially if it might be a boojum). Often used to refer to an event or a log file entry that might indicate an attempted security violation. See snivitz.
UUCP name of snark.thyrsus.com, home site of the Jargon File 2.*.* versions (i.e., this lexicon).

sneakernet /snee'ker-net/ n. Term used (generally with ironic intent) for transfer of electronic information by physically carrying tape, disks, or some other media from one machine to another. "Never underestimate the bandwidth of a station wagon filled with magtape, or a 747 filled with CD-ROMs." Also called `Tennis-Net', `Armpit-Net', `Floppy-Net' or `Shoenet'.

sniff v.,n. Synonym for poll.

snivitz /sniv'itz/ n. A hiccup in hardware or software; a small, transient problem of unknown origin (less serious than a snark). Compare glitch.

SO /S-O/ n.

(also `S.O.') Abbrev. for Significant Other, almost invariably written abbreviated and pronounced /S-O/ by hackers. Used to refer to one's primary relationship, esp. a live-in to whom one is not married. See MOTAS, MOTOS, MOTSS.
The Shift Out control character in ASCII (Control-N, 0001110).

social engineering n. Term used among crackers and samurai for cracking techniques that rely on weaknesses in wetware rather than software; the aim is to trick people into revealing passwords or other information that compromises a target system's security. Classic scams include phoning up a mark who has the required information and posing as a field service tech or a fellow employee with an urgent access problem. See also the tiger team story in the patch entry.

social science number [IBM] n. A statistic that is content-free, or nearly so. A measure derived via methods of questionable validity from data of a dubious and vague nature. Predictively, having a social science number in hand is seldom much better than nothing, and can be considerably worse. Management loves them. See also numbers, math-out, pretty pictures.

soft boot n. See boot.

softcopy /soft'kop-ee/ n. [by analogy with `hardcopy'] A machine-readable form of corresponding hardcopy. See bits, machinable.

software bloat n. The results of second-system effect or creeping featuritis. Commonly cited examples include `ls(1)', X, BSD, Missed'Em-Five, and OS/2.

software laser n. An optical laser works by bouncing photons back and forth between two mirrors, one totally reflective and one partially reflective. If the lasing material (usually a crystal) has the right properties, photons scattering off the atoms in the crystal will excite cascades of more photons, all in lockstep. Eventually the beam will escape through the partially-reflective mirror. One kind of sorcerer's apprentice mode involving bounce messages can produce closely analogous results, with a cascade of messages escaping to flood nearby systems. By mid-1993 there had been at least two publicized incidents of this kind.

software rot n. Term used to describe the tendency of software that has not been used in a while to lose; such failure may be semi-humorously ascribed to bit rot. More commonly, `software rot' strikes when a program's assumptions become out of date. If the design was insufficiently robust, this may cause it to fail in mysterious ways.

For example, owing to endemic shortsightedness in the design of COBOL programs, most will succumb to software rot when their 2-digit year counters wrap around at the beginning of the year 2000. Actually, related lossages often afflict centenarians who have to deal with computer software designed by unimaginative clods. One such incident became the focus of a minor public flap in 1990, when a gentleman born in 1889 applied for a driver's license renewal in Raleigh, North Carolina. The new system refused to issue the card, probably because with 2-digit years the ages 101 and 1 cannot be distinguished.

Historical note: Software rot in an even funnier sense than the mythical one was a real problem on early research computers (e.g., the R1; see grind crank). If a program that depended on a peculiar instruction hadn't been run in quite a while, the user might discover that the opcodes no longer did the same things they once did. ("Hey, so-and-so needs an instruction to do such-and-such. We can snarf this opcode, right? No one uses it.")

Another classic example of this sprang from the time an MIT hacker found a simple way to double the speed of the unconditional jump instruction on a PDP-6, so he patched the hardware. Unfortunately, this broke some fragile timing software in a music-playing program, throwing its output out of tune. This was fixed by adding a defensive initialization routine to compare the speed of a timing loop with the real-time clock; in other words, it figured out how fast the PDP-6 was that day, and corrected appropriately.

Compare bit rot.

softwarily /soft-weir'i-lee/ adv. In a way pertaining to software. "The system is softwarily unreliable." The adjective **`softwary' is *not* used. See hardwarily.

softy [IBM] n. Hardware hackers' term for a software expert who is largely ignorant of the mysteries of hardware.

some random X adj. Used to indicate a member of class X, with the implication that Xs are interchangeable. "I think some random cracker tripped over the guest timeout last night." See also J. Random.

sorcerer's apprentice mode [from Friedrich Schiller's "Der Zauberlehrling" via the film "Fantasia"] n. A bug in a protocol where, under some circumstances, the receipt of a message causes multiple messages to be sent, each of which, when received, triggers the same bug. Used esp. of such behavior caused by bounce message loops in email software. Compare broadcast storm, network meltdown, software laser, ARMM.

SOS n.,obs. /S-O-S/

An infamously losing text editor. Once, back in the 1960s, when a text editor was needed for the PDP-6, a hacker crufted together a quick-and-dirty `stopgap editor' to be used until a better one was written. Unfortunately, the old one was never really discarded when new ones (in particular, TECO) came along. SOS is a descendant (`Son of Stopgap') of that editor, and many PDP-10 users gained the dubious pleasure of its acquaintance. Since then other programs similar in style to SOS have been written, notably the early font editor BILOS /bye'lohs/, the Brother-In-Law Of Stopgap (the alternate expansion `Bastard Issue, Loins of Stopgap' has been proposed).
/sos/ vt. To decrease; inverse of AOS, from the PDP-10 instruction set.

source of all good bits n. A person from whom (or a place from which) useful information may be obtained. If you need to know about a program, a guru might be the source of all good bits. The title is often applied to a particularly competent secretary.

space-cadet keyboard n. A now-legendary device used on MIT LISP machines, which inspired several still-current jargon terms and influenced the design of EMACS. It was equipped with no fewer than *seven* shift keys: four keys for bucky bits (`control', `meta', `hyper', and `super') and three like regular shift keys, called `shift', `top', and `front'. Many keys had three symbols on them: a letter and a symbol on the top, and a Greek letter on the front. For example, the `L' key had an `L' and a two-way arrow on the top, and the Greek letter lambda on the front. By pressing this key with the right hand while playing an appropriate `chord' with the left hand on the shift keys, you could get the following results:

     L               
          lowercase l

     shift-L         
          uppercase L

     front-L         
          lowercase lambda

     front-shift-L   
          uppercase lambda

     top-L           
          two-way arrow
          (front and shift are ignored)

And of course each of these might also be typed with any combination of the control, meta, hyper, and super keys. On this keyboard, you could type over 8000 different characters! This allowed the user to type very complicated mathematical text, and also to have thousands of single-character commands at his disposal. Many hackers were actually willing to memorize the command meanings of that many characters if it reduced typing time (this attitude obviously shaped the interface of EMACS). Other hackers, however, thought having that many bucky bits was overkill, and objected that such a keyboard can require three or four hands to operate. See bucky bits, cokebottle, double bucky, meta bit, quadruple bucky.

Note: early versions of this entry incorrectly identified the space-cadet keyboard with the `Knight keyboard'. Though both were designed by Tom Knight, the latter term was properly applied only to a keyboard used for ITS on the PDP-10 and modeled on the Stanford keyboard (as described under bucky bits). The true space-cadet keyboard evolved from the Knight keyboard.

SPACEWAR n. A space-combat simulation game, inspired by E. E. "Doc" Smith's "Lensman" books, in which two spaceships duel around a central sun, shooting torpedoes at each other and jumping through hyperspace. This game was first implemented on the PDP-1 at MIT in 1960--61. SPACEWAR aficionados formed the core of the early hacker culture at MIT. Nine years later, a descendant of the game motivated Ken Thompson to build, in his spare time on a scavenged PDP-7, the operating system that became UNIX. Less than nine years after that, SPACEWAR was commercialized as one of the first video games; descendants are still feeping in video arcades everywhere.

spaghetti code n. Code with a complex and tangled control structure, esp. one using many GOTOs, exceptions, or other `unstructured' branching constructs. Pejorative. The synonym `kangaroo code' has been reported, doubtless because such code has so many jumps in it.

spaghetti inheritance n. [encountered among users of object-oriented languages that use inheritance, such as Smalltalk] A convoluted class-subclass graph, often resulting from carelessly deriving subclasses from other classes just for the sake of reusing their code. Coined in a (successful) attempt to discourage such practice, through guilt-by-association with spaghetti code.

spam [from the MUD community] vt.

To crash a program by overrunning a fixed-size buffer with excessively large input data. See also buffer overflow, overrun screw, smash the stack.
To cause a newsgroup to be flooded with irrelevant or inappropriate messages. You can spam a newsgroup with as little as one well- (or ill-) planned message (e.g. asking "What do you think of abortion?" on soc.women). This is often done with cross-posting (e.g. any message which is crossposted to alt.rush-limbaugh and alt.politics.homosexuality will almost inevitably spam both groups).

special-case vt. To write unique code to handle input to or situations arising in a program that are somehow distinguished from normal processing. This would be used for processing of mode switches or interrupt characters in an interactive interface (as opposed, say, to text entry or normal commands), or for processing of hidden flags in the input of a batch program or filter.

speedometer n. A pattern of lights displayed on a linear set of LEDs (today) or nixie tubes (yesterday, on ancient mainframes). The pattern is shifted left every N times the operating system goes through its main loop. A swiftly moving pattern indicates that the system is mostly idle; the speedometer slows down as the system becomes overloaded. The speedometer on Sun Microsystems hardware bounces back and forth like the eyes on one of the Cylons from the wretched "Battlestar Galactica" TV series.

Historical note: One computer, the GE 600 (later Honeywell 6000) actually had an *analog* speedometer on the front panel, calibrated in instructions executed per second.

spell n. Syn. incantation.

spelling flame [USENET] n. A posting ostentatiously correcting a previous article's spelling as a way of casting scorn on the point the article was trying to make, instead of actually responding to that point (compare dictionary flame). Of course, people who are more than usually slovenly spellers are prone to think *any* correction is a spelling flame. It's an amusing comment on humAn nature that spelling flames themselves often contain spelling errors.

spiffy /spi'fee/ adj.

Said of programs having a pretty, clever, or exceptionally well-designed interface. "Have you seen the spiffy X version of empire yet?"
Said sarcastically of a program that is perceived to have little more than a flashy interface going for it. Which meaning should be drawn depends delicately on tone of voice and context. This word was common mainstream slang during the 1940s, in a sense close to 1.

spike v. To defeat a selection mechanism by introducing a (sometimes temporary) device that forces a specific result. The word is used in several industries; telephone engineers refer to spiking a relay by inserting a pin to hold the relay in either the closed or open state, and railroaders refer to spiking a track switch so that it cannot be moved. In programming environments it normally refers to a temporary change, usually for testing purposes (as opposed to a permanent change, which would be called hardwired).

spin vi. Equivalent to buzz. More common among C and UNIX programmers.

spl /S-P-L/ [abbrev, from Set Priority Level] The way traditional UNIX kernels implement mutual exclusion by running code at high interrupt levels. Used in jargon to describe the act of tuning in or tuning out ordinary communication. Classically, spl levels run from 1 to 7; "Fred's at spl 6 today" would mean that he is very hard to interrupt. "Wait till I finish this; I'll spl down then." See also interrupts locked out.

splash screen [Mac] n. Syn. banner, sense 3.

splat n.

Name used in many places (DEC, IBM, and others) for the asterisk (`*') character (ASCII 0101010). This may derive from the `squashed-bug' appearance of the asterisk on many early line printers.
[MIT] Name used by some people for the `#' character (ASCII 0100011).
[Rochester Institute of Technology] The feature key on a Mac (same as alt, sense 2).
obs. Name used by some people for the Stanford/ITS extended ASCII circle-x character. This character is also called `blobby' and `frob', among other names; it is sometimes used by mathematicians as a notation for `tensor product'.
obs. Name for the semi-mythical Stanford extended ASCII circle-plus character. See also ASCII.

spod [Great Britain] n. A lower form of life found on talker systems and MUDs. The spod has few friends in RL and uses talkers instead, finding communication easier and preferable over the net. He has all the negative traits of the computer geek without having any interest in computers per se. Lacking any knowledge of or interest in how networks work, and considering his access a God-given right, he is a major irritant to sysadmins, clogging up lines in order to reach new MUDs, following passed-on instructions on how to sneak his way onto Internet ("Wow! It's in America!") and complaining when he is not allowed to use busy routes. A true spod will start any conversation with "Are you male or female?" (and follow it up with "Got any good numbers/IDs/passwords?") and will not talk to someone physically present in the same terminal room until they log onto the same machine that he is using and enter talk mode. Compare newbie, tourist, weenie, twink, terminal junkie.

spoiler [USENET] n.

A remark which reveals important plot elements from books or movies, thus denying the reader (of the article) the proper suspense when reading the book or watching the movie.
Any remark which telegraphs the solution of a problem or puzzle, thus denying the reader the pleasure of working out the correct answer (see also interesting). Either sense readily forms compounds like `total spoiler', `quasi-spoiler' and even `pseudo-spoiler'.

By convention, articles which are spoilers in either sense should contain the word `spoiler' in the Subject: line, or guarantee via various tricks that the answer appears only after several screens-full of warning, or conceal the sensitive information via rot13, or some combination of these techniques.

sponge [UNIX] n. A special case of a filter that reads its entire input before writing any output; the canonical example is a sort utility. Unlike most filters, a sponge can conveniently overwrite the input file with the output data stream. If a file system has versioning (as ITS did and VMS does now) the sponge/filter distinction loses its usefulness, because directing filter output would just write a new version. See also slurp.

spoo n. Variant of spooge, sense 1.

spooge /spooj/

n. Inexplicable or arcane code, or random and probably incorrect output from a computer program.
vi. To generate spooge (sense 1).

spool [from early IBM `Simultaneous Peripheral Operation On-Line', but this acronym is widely thought to have been contrived for effect] vt. To send files to some device or program (a `spooler') that queues them up and does something useful with them later. Without qualification, the spooler is the `print spooler' controlling output of jobs to a printer; but the term has been used in connection with other peripherals (especially plotters and graphics devices) and occasionally even for input devices. See also demon.

spool file n. Any file to which data is spooled to await the next stage of processing. Especially used in circumstances where spooling the data copes with a mismatch between speeds in two devices or pieces of software. For example, when you send mail under UNIX, it's typically copied to a spool file to await a transport demon's attentions. This is borderline techspeak.

square tape n. Mainframe magnetic tape cartridges for use with IBM 3480 or compatible tape drives; or QIC tapes used on workstations and micros. The term comes from the square (actually rectangular) shape of the cartridges; contrast round tape.

stack n. The set of things a person has to do in the future. One speaks of the next project to be attacked as having risen to the top of the stack. "I'm afraid I've got real work to do, so this'll have to be pushed way down on my stack." "I haven't done it yet because every time I pop my stack something new gets pushed." If you are interrupted several times in the middle of a conversation, "My stack overflowed" means "I forget what we were talking about." The implication is that more items were pushed onto the stack than could be remembered, so the least recent items were lost. The usual physical example of a stack is to be found in a cafeteria: a pile of plates or trays sitting on a spring in a well, so that when you put one on the top they all sink down, and when you take one off the top the rest spring up a bit. See also push and pop.

At MIT, pdl used to be a more common synonym for stack in all these contexts, and this may still be true. Everywhere else stack seems to be the preferred term. Knuth ("The Art of Computer Programming", second edition, vol. 1, p. 236) says:

        Many people who realized the importance of stacks and queues
        independently have given other names to these structures:
        stacks have been called push-down lists, reversion storages,
        cellars, nesting stores, piles, last-in-first-out ("LIFO")
        lists, and even yo-yo lists!

stack puke n. Some processor architectures are said to `puke their guts onto the stack' to save their internal state during exception processing. The Motorola 68020, for example, regurgitates up to 92 bytes on a bus fault. On a pipelined machine, this can take a while.

stale pointer bug n. Synonym for aliasing bug used esp. among microcomputer hackers.

state n.

Condition, situation. "What's the state of your latest hack?" "It's winning away." "The system tried to read and write the disk simultaneously and got into a totally wedged state." The standard question "What's your state?" means "What are you doing?" or "What are you about to do?" Typical answers are "about to gronk out", or "hungry". Another standard question is "What's the state of the world?", meaning "What's new?" or "What's going on?". The more terse and humorous way of asking these questions would be "State-p?". Another way of phrasing the first question under sense 1 would be "state-p latest hack?".
Information being maintained in non-permanent memory (electronic or human).

steam-powered adj. Old-fashioned or underpowered; archaic. This term does not have a strong negative loading and may even be used semi-affectionately for something that clanks and wheezes a lot but hangs in there doing the job.

stiffy [University of Lowell, Massachusetts.] n. 3.5-inch microfloppies, so called because their jackets are more rigid than those of the 5.25-inch and the (now totally obsolete) 8-inch floppy. Elsewhere this might be called a `firmy'.

stir-fried random alt. `stir-fried mumble' n. Term used for the best dish of many of those hackers who can cook. Consists of random fresh veggies and meat wokked with random spices. Tasty and economical. See random, great-wall, ravs, laser chicken, oriental food; see also mumble.

stomp on vt. To inadvertently overwrite something important, usually automatically. "All the work I did this weekend got stomped on last night by the nightly server script." Compare scribble, mangle, trash, scrog, roach.

Stone Age n., adj.

In computer folklore, an ill-defined period from ENIAC (ca. 1943) to the mid-1950s; the great age of electromechanical dinosaurs. Sometimes used for the entire period up to 1960--61 (see Iron Age); however, it is funnier and more descriptive to characterize the latter period in terms of a `Bronze Age' era of transistor-logic, pre-ferrite-core machines with drum or CRT mass storage (as opposed to just mercury delay lines and/or relays). See also Iron Age.
More generally, a pejorative for any crufty, ancient piece of hardware or software technology. Note that this is used even by people who were there for the Stone Age (sense 1).

stone knives and bearskins [from the Star Trek Classic episode "The City on the Edge of Forever"] n. A term traditionally used to describe (and deprecate) computing environments that are grotesquely primitive in light of what is known about good ways to design things. As in "Don't get too used to the facilities here. Once you leave SAIL it's stone knives and bearskins as far as the eye can see". Compare steam-powered.

stoppage /sto'p*j/ n. Extreme lossage that renders something (usually something vital) completely unusable. "The recent system stoppage was caused by a fried transformer."

store [prob. from techspeak `main store'] n. In some varieties of Commonwealth hackish, the preferred synonym for core. Thus, `bringing a program into store' means not that one is returning shrink-wrapped software but that a program is being swapped in.

strided /str:'d*d/ [scientific computing] adj. Said of a sequence of memory reads and writes to addresses, each of which is separated from the last by a constant interval called the `stride length'. These can be a worst-case access pattern for the standard memory-caching schemes when the stride length is a multiple of the cache line size. Strided references are often generated by loops through an array, and (if youre data is large enough that access-time is significant) it can be worthwhile to tune for better locality by inverting double loops or by partially unrolling the outer loop of a loop nest. This usage is borderline techspeak; the related term `memory stride' is definitely techspeak.

stroke n. Common name for the slant (`/', ASCII 0101111) character. See ASCII for other synonyms.

strudel n. Common (spoken) name for the at-sign (`@', ASCII 1000000) character. See ASCII for other synonyms.

stubroutine /stuhb'roo-teen/ [contraction of `stub subroutine'] n. Tiny, often vacuous placeholder for a subroutine that is to be written or fleshed out later.

studly adj. Impressive; powerful. Said of code and designs which exhibit both complexity and a virtuoso flair. Has connotations similar to hairy but is more positive in tone. Often in the emphatic `most studly' or as noun-form `studliness'. "Smail 3.0's configuration parser is most studly."

studlycaps /stuhd'lee-kaps/ n. A hackish form of silliness similar to BiCapitalization for trademarks, but applied randomly and to arbitrary text rather than to trademarks. ThE oRigiN and SigNificaNce of thIs pRacTicE iS oBscuRe.

stunning adj. Mind-bogglingly stupid. Usually used in sarcasm. "You want to code *what* in ADA? That's a ... stunning idea!"

stupid-sort n. Syn. bogo-sort.

Stupids n. Term used by samurai for the suits who employ them; succinctly expresses an attitude at least as common, though usually better disguised, among other subcultures of hackers. There may be intended reference here to an SF story originally published in 1952 but much anthologized since, Mark Clifton's "Star, Bright". In it, a super-genius child classifies humans into a very few `Brights' like herself, a huge majority of `Stupids', and a minority of `Tweens', the merely ordinary geniuses.

Sturgeon'S Law prov. "Ninety percent of everything is crap". Derived from a quote by science fiction author Theodore Sturgeon, who once said, "Sure, 90% of science fiction is crud. That's because 90% of everything is crud." Oddly, when Sturgeon's Law is cited, the final word is almost invariably changed to `crap'. Compare Hanlon'S Razor, Ninety-Ninety Rule. Though this maxim originated in SF fandom, most hackers recognize it and are all too aware of its truth.

sucking mud [Applied Data Research] adj. (also `pumping mud') Crashed or wedged. Usually said of a machine that provides some service to a network, such as a file server. This Dallas regionalism derives from the East Texas oilfield lament, "Shut 'er down, Ma, she's a-suckin' mud". Often used as a query. "We are going to reconfigure the network, are you ready to suck mud?"

sufficiently small adj. Syn. suitably small.

suit n.

suitable win n. See win.

suitably small [perverted from mathematical jargon] adj. An expression used ironically to characterize unquantifiable behavior that differs from expected or required behavior. For example, suppose a newly created program came up with a correct full-screen display, and one publicly exclaimed: "It works!" Then, if the program dumped core on the first mouse click, one might add: "Well, for suitably small values of `works'." Compare the characterization of pi under random numbers.

sun lounge [Great Britain] n. The room where all the Sun workstations live. The humor in this term comes from the fact that it's also in mainstream use to describe a solarium, and all those Sun workstations clustered together give off an amazing amount of heat.

sun-stools n. Unflattering hackerism for SunTools, a pre-X windowing environment notorious in its day for size, slowness, and misfeatures. X, however, is larger and slower; see second-system effect.

sunspots n.

Notional cause of an odd error. "Why did the program suddenly turn the screen blue?" "Sunspots, I guess."
Also the cause of bit rot --- from the myth that sunspots will increase cosmic rays, which can flip single bits in memory. See also phase of the moon.

super source quench n. A special packet designed to shut up an Internet host. The Internet Protocol (IP) has a control message called Source Quench that asks a host to transmit more slowly on a particular connection to avoid congestion. It also has a Redirect control message intended to instruct a host to send certain packets to a different local router. A "super source quench" is actually a redirect control packet, forged to look like it came from a local router, that instructs a host to send all packets to its own local loopback address. This will effectively tie many Internet hosts up in knots. Compare godzillagram, breath-of-life packet.

superprogrammer n. A prolific programmer; one who can code exceedingly well and quickly. Not all hackers are superprogrammers, but many are. (Productivity can vary from one programmer to another by three orders of magnitude. For example, one programmer might be able to write an average of 3 lines of working code in one day, while another, with the proper tools, might be able to write 3,000. This range is astonishing; it is matched in very few other areas of human endeavor.) The term `superprogrammer' is more commonly used within such places as IBM than in the hacker community. It tends to stress naive measures of productivity and to underweight creativity, ingenuity, and getting the job *done* --- and to sidestep the question of whether the 3,000 lines of code do more or less useful work than three lines that do the Right Thing. Hackers tend to prefer the terms hacker and wizard.

superuser [UNIX] n. Syn. root, avatar. This usage has spread to non-UNIX environments; the superuser is any account with all wheel bits on. A more specific term than wheel.

support n. After-sale handholding; something many software vendors promise but few deliver. To hackers, most support people are useless --- because by the time a hacker calls support he or she will usually know the software and the relevant manuals better than the support people (sadly, this is *not* a joke or exaggeration). A hacker's idea of `support' is a t^ete-`a-t^ete with the software's designer.

Suzie COBOL /soo'zee koh'bol/

[IBM: prob. from Frank Zappa's `Suzy Creamcheese'] n. A coder straight out of training school who knows everything except the value of comments in plain English. Also (fashionable among personkind wishing to avoid accusations of sexism) `Sammy Cobol' or (in some non-IBM circles) `Cobol Charlie'.

[proposed] Meta-name for any code grinder, analogous to J. Random Hacker.

swab /swob/ [From the mnemonic for the PDP-11 `SWAp Byte' instruction, as immortalized in the `dd(1)' option `conv=swab' (see dd)]

vt. To solve the NUXI Problem by swapping bytes in a file.
n. The program in V7 UNIX used to perform this action, or anything functionally equivalent to it. See also big-endian, little-endian, middle-endian, bytesexual.

swap vt.

[techspeak] To move information from a fast-access memory to a slow-access memory (`swap out'), or vice versa (`swap in'). Often refers specifically to the use of disks as `virtual memory'. As pieces of data or program are needed, they are swapped into core for processing; when they are no longer needed they may be swapped out again.
The jargon use of these terms analogizes people's short-term memories with core. Cramming for an exam might be spoken of as swapping in. If you temporarily forget someone's name, but then remember it, your excuse is that it was swapped out. To `keep something swapped in' means to keep it fresh in your memory: "I reread the TECO manual every few months to keep it swapped in." If someone interrupts you just as you got a good idea, you might say "Wait a moment while I swap this out", implying that a piece of paper is your extra-somatic memory and that if you don't swap the idea out by writing it down it will get overwritten and lost as you talk. Compare page in, page out.

swap space n. Storage space, especially temporary storage space used during a move or reconfiguration. "I'm just using that corner of the machine room for swap space."

swapped in n. See swap. See also page in.

swapped out n. See swap. See also page out.

swizzle v. To convert external names, array indices, or references within a data structure into address pointers when the data structure is brought into main memory from external storage (also called `pointer swizzling'); this may be done for speed in chasing references or to simplify code (e.g., by turning lots of name lookups into pointer dereferences). The converse operation is sometimes termed `unswizzling'. See also snap.

sync /sink/ (var. `synch') n., vi.

To synchronize, to bring into synchronization.
[techspeak] To force all pending I/O to the disk; see flush, sense 2.
More generally, to force a number of competing processes or agents to a state that would be `safe' if the system were to crash; thus, to checkpoint (in the database-theory sense).

syntactic salt n. The opposite of syntactic sugar, a feature designed to make it harder to write bad code. Specifically, syntactic salt is a hoop the programmer must jump through just to prove that he knows what's going on, rather than to express a program action. Some programmers consider required type declarations to be syntactic salt. A requirement to write `end if', `end while', `end do', etc. to terminate the last block controlled by a control construct (as opposed to just `end') would definitely be syntactic salt. Syntactic salt is like the real thing in that it tends to raise hackers' blood pressures in an unhealthy way. Compare candygrammar. .

syntactic sugar [coined by Peter Landin] n. Features added to a language or other formalism to make it `sweeter' for humans, features which do not affect the expressiveness of the formalism (compare chrome). Used esp. when there is an obvious and trivial translation of the `sugar' feature into other constructs already present in the notation. C's `a[i]' notation is syntactic sugar for `*(a + i)'. "Syntactic sugar causes cancer of the semicolon." --- Alan Perlis.

The variants `syntactic saccharin' and `syntactic syrup' are also recorded. These denote something even more gratuitous, in that syntactic sugar serves a purpose (making something more acceptable to humans), but syntactic saccharin or syrup serve no purpose at all. Compare candygrammar, syntactic salt.

sys-frog /sis'frog/ [the PLATO system] n. Playful variant of `sysprog', which is in turn short for `systems programmer'.

sysadmin /sis'ad-min/ n. Common contraction of `system admin'; see admin.

sysape /sys'ayp/ n. A rather derogatory term for a computer operator; a play on sysop common at sites that use the banana hierarchy of problem complexity (see one-banana problem).

sysop /sis'op/ n. [esp. in the BBS world] The operator (and usually the owner) of a bulletin-board system. A common neophyte mistake on FidoNet is to address a message to `sysop' in an international echo, thus sending it to hundreds of sysops around the world.

system n.

The supervisor program or OS on a computer.
The entire computer system, including input/output devices, the supervisor program or OS, and possibly other software.
Any large-scale program.
Any method or algorithm.
`System hacker': one who hacks the system (in senses 1 and 2 only; for sense 3 one mentions the particular program: e.g., `LISP hacker')

systems jock n. See jock, sense 2.

system mangler n. Humorous synonym for `system manager', poss. from the fact that one major IBM OS had a root account called SYSMANGR. Refers specifically to a systems programmer in charge of administration, software maintenance, and updates at some site. Unlike admin, this term emphasizes the technical end of the skills involved.

SysVile /sis-vi:l'/ n. See Missed'Em-Five.