The Hacker's Dictionary, - [best reads of all time .txt] 📗

change. That wasn't the last time this happened, either. The author ofThe 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 renamedCBW' 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 instructionsORL' and `ANL'.

The Motorola 6809, used in the U.K.'s Dragon 32' personal computer, actually had an officialSEX' instruction; the 6502

in the Apple II it competed with 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: n. A UNIX symbolic link, particularly when it confuses you, points to nothing at all, or results in you ending up in some completely unexpected part of the filesystem....

: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. 2. 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] 1. vi. To move oneself to the left (right). To move out of the way. 2. imper. "Get out of that (my) seat! You can shift to that empty one to the left (right)." Often used without the logical', or asleft 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.

: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. 1. Syn. {slap on the side}. Esp. used of add-ons for the late and unlamented IBM PCjr. 2. 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 rules.

If it worked with any other peripherals, it was by {magic}.

:SIG: n. The Association for Computing Machinery traditionally sponsors Special Interest Groups in various technical areas; well-known ones include 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.

: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, andnoise' 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 war}s.

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}.

:silicon foundry: n. A company that {fab}s chips to the designs of others. As of the late 1980s, the combination of silicon foundries and good computer-aided design software made it much easier for hardware-designing startup companies to come into being.

The downside of using a silicon foundry is that the distance from the actual chip-fabrication processes reduces designers' control of detail. This is somewhat analogous to the use of {HLL}s versus coding in assembler.

:silly walk: [from Monty Python's Flying Circus] vi. 1. 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." 2. 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 you put in the top and took out 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: adj. 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}.

: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