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

levels of &',|', ^',<<', and `>>' (for this reason, experienced C programmers deliberately forget the language's {baroque} precedence hierarchy and parenthesize defensively). Can always be avoided by suitable use of parentheses. {LISP} fans enjoy pointing out that this can't happen in their favorite language, which eschews precedence entirely, requiring one to use explicit parentheses everywhere. See {aliasing bug}, {memory leak}, {memory smash}, {smash the stack}, {fandango on core}, {overrun screw}.

:prepend: /preepend'/ [by analogy withappend'] vt. To prefix. As with append' (but notprefix' or `suffix' as a verb), the direct object is always the thing being added and not the original word (or character string, or whatever). "If you prepend a semicolon to the line, the translation routine will pass it through unaltered."

:prestidigitization: /prest*-dij-ti:-zay'shn/ n. 1. The act of putting something into digital notation via sleight of hand.

Data entry through legerdemain.

:pretty pictures: n. [scientific computation] The next step up from {numbers}. Interesting graphical output from a program that may not have any sensible relationship to the system the program is intended to model. Good for showing to {management}.

:prettyprint: /prit'ee-print/ (alt. pretty-print') v. 1. To generatepretty' human-readable output from a {hairy} internal representation; esp. used for the process of {grind}ing (sense 2) LISP code. 2. To format in some particularly slick and nontrivial way.

:pretzel key: [Mac users] n. See {feature key}.

:prime time: [from TV programming] n. Normal high-usage hours on a timesharing system; the day shift. Avoidance of prime time is a major reason for {night mode} hacking.

:printing discussion: [PARC] n. A protracted, low-level, time-consuming, generally pointless discussion of something only peripherally interesting to all.

:priority interrupt: [from the hardware term] n. Describes any stimulus compelling enough to yank one right out of {hack mode}.

Classically used to describe being dragged away by an {SO} for immediate sex, but may also refer to more mundane interruptions such as a fire alarm going off in the near vicinity. Also called an {NMI} (non-maskable interrupt), especially in PC-land.

:profile: n. 1. A control file for a program, esp. a text file automatically read from each user's home directory and intended to be easily modified by the user in order to customize the program's behavior. Used to avoid {hardcoded} choices. 2. [techspeak] A report on the amounts of time spent in each routine of a program, used to find and {tune} away the {hot spot}s in it. This sense is often verbed. Some profiling modes report units other than time (such as call counts) and/or report at granularities other than per-routine, but the idea is similar.

:proglet: /prog'let/ [UK] n. A short extempore program written to meet an immediate, transient need. Often written in BASIC, rarely more than a dozen lines long, and contains no subroutines.

The largest amount of code that can be written off the top of one's head, that does not need any editing, and that runs correctly the first time (this amount varies significantly according to the language one is using). Compare {toy program}, {noddy}, {one-liner wars}.

:program: n. 1. A magic spell cast over a computer allowing it to turn one's input into error messages. 2. An exercise in experimental epistemology. 3. A form of art, ostensibly intended for the instruction of computers, which is nevertheless almost inevitably a failure if other programmers can't understand it.

:Programmer's Cheer: "Shift to the left! Shift to the right! Pop up, push down! Byte! Byte! Byte!" A joke so old it has hair on it.

:programming: n. 1. The art of debugging a blank sheet of paper (or, in these days of on-line editing, the art of debugging an empty file). 2. n. A pastime similar to banging one's head against a wall, but with fewer opportunities for reward. 3. n. The most fun you can have with your clothes on (although clothes are not mandatory).

:programming fluid: n. 1. Coffee. 2. Cola. 3. Any caffeinacious stimulant. Many hackers consider these essential for those all-night hacking runs. See {unleaded}, {wirewater}.

:propeller head: n. Used by hackers, this is syn. with {computer geek}. Non-hackers sometimes use it to describe all techies.

Prob. derives from SF fandom's tradition (originally invented by old-time fan Ray Faraday Nelson) of propeller beanies as fannish insignia (though nobody actually wears them except as a joke).

:propeller key: [Mac users] n. See {feature key}.

:proprietary: adj. 1. In {marketroid}-speak, superior; implies a product imbued with exclusive magic by the unmatched brilliance of the company's hardware or software designers. 2. In the language of hackers and users, inferior; implies a product not conforming to open-systems standards, and thus one that puts the customer at the mercy of a vendor able to gouge freely on service and upgrade charges after the initial sale has locked the customer in (that's assuming it wasn't too expensive in the first place).

:protocol: n. As used by hackers, this never refers to niceties about the proper form for addressing letters to the Papal Nuncio or the order in which one should use the forks in a Russian-style place setting; hackers don't care about such things. It is used instead to describe any set of rules that allow different machines or pieces of software to coordinate with each other without ambiguity. So, for example, it does include niceties about the proper form for addressing packets on a network or the order in which one should use the forks in the Dining Philosophers Problem.

It implies that there is some common message format and an accepted set of primitives or commands that all parties involved understand, and that transactions among them follow predictable logical sequences. See also {handshaking}, {do protocol}.

:provocative maintenance: [common ironic mutation of `preventive maintenance'] n. Actions performed upon a machine at regularly scheduled intervals to ensure that the system remains in a usable state. So called because it is all too often performed by a {field servoid} who doesn't know what he is doing; this results in the machine's remaining in an unusable state for an indeterminate amount of time. See also {scratch monkey}.

:prowler: [UNIX] n. A {daemon} that is run periodically (typically once a week) to seek out and erase {core} files, truncate administrative logfiles, nuke `lost+found' directories, and otherwise clean up the {cruft} that tends to pile up in the corners of a file system. See also {GFR}, {reaper}, {skulker}.

:pseudo: /soo'doh/ [USENET: truncation of pseudonym'] n. 1. An electronic-mail or {USENET} persona adopted by a human for amusement value or as a means of avoiding negative repercussions of one's net.behavior; anom de USENET', often associated with forged postings designed to conceal message origins. Perhaps the best-known and funniest hoax of this type is {BIFF}.

Notionally, a {flamage}-generating AI program simulating a USENET user. Many flamers have been accused of actually being such entities, despite the fact that no AI program of the required sophistication yet exists. However, in 1989 there was a famous series of forged postings that used a phrase-frequency-based travesty generator to simulate the styles of several well-known flamers; it was based on large samples of their back postings (compare {Dissociated Press}). A significant number of people were fooled by the forgeries, and the debate over their authenticity was settled only when the perpetrator came forward to publicly admit the hoax.

:pseudoprime: n. A backgammon prime (six consecutive occupied points) with one point missing. This term is an esoteric pun derived from a mathematical method that, rather than determining precisely whether a number is prime (has no divisors), uses a statistical technique to decide whether the number is `probably'

prime. A number that passes this test is called a pseudoprime.

The hacker backgammon usage stems from the idea that a pseudoprime is almost as good as a prime: it does the job of a prime until proven otherwise, and that probably won't happen.

:pseudosuit: /soo'doh-s[y]oot`/ n. A {suit} wannabee; a hacker who has decided that he wants to be in management or administration and begins wearing ties, sport coats, and (shudder!) suits voluntarily. It's his funeral. See also {lobotomy}.

:psychedelicware: /si:`k*-del'-ik-weir/ [UK] n. Syn.

{display hack}. See also {smoking clover}.

:psyton: /si:'ton/ [TMRC] n. The elementary particle carrying the sinister force. The probability of a process losing is proportional to the number of psytons falling on it. Psytons are generated by observers, which is why demos are more likely to fail when lots of people are watching. [This term appears to have been largely superseded by {bogon}; see also {quantum bogodynamics}.

--- ESR]

:pubic directory: [NYU] (also `pube directory' /pyoob'

d-rek't-ree/) n. The `pub' (public) directory on a machine that allows {FTP} access. So called because it is the default location for {SEX} (sense 1). "I'll have the source in the pube directory by Friday."

:puff: vt. To decompress data that has been crunched by Huffman coding. At least one widely distributed Huffman decoder program was actually named `PUFF', but these days it is usually packaged with the encoder. Oppose {huff}.

:punched card:: alt. `punch card' [techspeak] n.obs. The signature medium of computing's {Stone Age}, now obsolescent outside of some IBM shops. The punched card actually predated computers considerably, originating in 1801 as a control device for mechanical looms. The version patented by Hollerith and used with mechanical tabulating machines in the 1890