Part 22

If someone starts a sentence with "Clearly..." or "Obviously..." or "It is self-evident that...", it is a good bet he is about to handwave (alternatively, use of these constructions in a sarcastic tone before a paraphrase of someone else's argument suggests that it is a handwave). The theory behind this term is that if you wave your hands at the right moment, the listener may be sufficiently distracted to not notice that what you have said is {bogus}. Failing that, if a listener does object, you might try to dismiss the objection with a wave of your hand.

The use of this word is often accompanied by gestures: both hands up, palms forward, swinging the hands in a vertical plane pivoting at the elbows and/or shoulders (depending on the magnitude of the handwave); alternatively, holding the forearms in one position while rotating the hands at the wrist to make them flutter. In context, the gestures alone can suffice as a remark; if a speaker makes an outrageously unsupported assumption, you might simply wave your hands in this way, as an accusation, far more eloquent than words could express, that his logic is faulty.

:hang: v. 1. To wait for an event that will never occur. "The system is hanging because it can't read from the crashed drive". See {wedged}, {hung}. 2. To wait for some event to occur; to hang around until something happens. "The program displays a menu and then hangs until you type a character." Compare {block}. 3. To attach a peripheral device, esp. in the construction `hang off': "We're going to hang another tape drive off the file server." Implies a device attached with cables, rather than something that is strictly inside the machine's chassis.

:Hanlon's Razor: prov. A corollary of {Finagle's Law}, similar to Occam's Razor, that reads "Never attribute to malice that which can be adequately explained by stupidity." The derivation of the common title Hanlon's Razor is unknown; a similar epigram has been attributed to William James. Quoted here because it seems to be a particular favorite of hackers, often showing up in {fortune cookie} files and the login banners of BBS systems and commercial networks. This probably reflects the hacker's daily experience of environments created by well-intentioned but short-sighted people.

:happily: adv. Of software, used to emphasize that a program is unaware of some important fact about its environment, either because it has been fooled into believing a lie, or because it doesn't care. The sense of `happy' here is not that of elation, but rather that of blissful ignorance. "The program continues to run, happily unaware that its output is going to /dev/null."

:haque: /hak/ [USENET] n. Variant spelling of {hack}, used only for the noun form and connoting an {elegant} hack.

:hard boot: n. See {boot}.

:hardcoded: adj. 1. Said of data inserted directly into a program, where it cannot be easily modified, as opposed to data in some {profile}, resource (see {de-rezz} sense 2), or environment variable that a {user} or hacker can easily modify. 2. In C, this is esp. applied to use of a literal instead of a `#define' macro (see {magic number}).

:hardwarily: /hard-weir'*-lee/ adv. In a way pertaining to hardware. "The system is hardwarily unreliable." The adjective `hardwary' is *not* traditionally used, though it has recently been reported from the U.K. See {softwarily}.

:hardwired: adj. 1. In software, syn. for {hardcoded}. 2. By extension, anything that is not modifiable, especially in the sense of customizable to one's particular needs or tastes.

:has the X nature: [seems to derive from Zen Buddhist koans of the form "Does an X have the Buddha-nature?"] adj. Common hacker construction for `is an X', used for humorous emphasis. "Anyone who can't even use a program with on-screen help embedded in it truly has the {loser} nature!" See also {the X that can be Y is not the true X}.

:hash bucket: n. A notional receptacle into which more than one thing accessed by the same key or short code might be dropped. When you look up a name in the phone book (for example), you typically hash it by extracting its first letter; the hash buckets are the alphabetically ordered letter sections. This is used as techspeak with respect to code that uses actual hash functions; in jargon, it is used for human associative memory as well. Thus, two things `in the same hash bucket' may be confused with each other. "If you hash English words only by length, you get too many common grammar words in the first couple of hash buckets." Compare {hash collision}.

:hash collision: [from the technical usage] n. (var. `hash clash') When used of people, signifies a confusion in associative memory or imagination, especially a persistent one (see {thinko}). True story: One of us [ESR] was once on the phone with a friend about to move out to Berkeley. When asked what he expected Berkeley to be like, the friend replied: "Well, I have this mental picture of naked women throwing Molotov cocktails, but I think that's just a collision in my hash tables." Compare {hash bucket}.

:hat: n. Common (spoken) name for the circumflex (`^', ASCII 1011110) character. See {ASCII} for other synonyms.

:HCF: /H-C-F/ n. Mnemonic for `Halt and Catch Fire', any of several undocumented and semi-mythical machine instructions with destructive side-effects, supposedly included for test purposes on several well-known architectures going as far back as the IBM 360. The MC6800 microprocessor was the first for which an HCF opcode became widely known. This instruction caused the processor to {toggle} a subset of the bus lines as rapidly as it could; in some configurations this could actually cause lines to burn up.

:heads down: [Sun] adj. Concentrating, usually so heavily and for so long that everything outside the focus area is missed. See also {hack mode} and {larval stage}, although it is not confined to fledgling hackers.

:heartbeat: n. 1. The signal emitted by a Level 2 Ethernet transceiver at the end of every packet to show that the collision-detection circuit is still connected. 2. A periodic synchronization signal used by software or hardware, such as a bus clock or a periodic interrupt. 3. The `natural' oscillation frequency of a computer's clock crystal, before frequency division down to the machine's clock rate. 4. A signal emitted at regular intervals by software to demonstrate that it is still alive. Sometimes hardware is designed to reboot the machine if it stops hearing a heartbeat. See also {breath-of-life packet}.

:heatseeker: [IBM] n. A customer who can be relied upon to always buy the latest version of an existing product (not quite the same as a member the {lunatic fringe}). A 1992 example of a heatseeker is someone who, owning a 286 PC and Windows 3.0, goes out and buys Windows 3.1 (which offers no worthwhile benefits unless you have a 386). If all customers were heatseekers, vast amounts of money could be made by just fixing the bugs in each release (n) and selling it to them as release (n+1).

:heavy metal: [Cambridge] n. Syn. {big iron}.

:heavy wizardry: n. Code or designs that trade on a particularly intimate knowledge or experience of a particular operating system or language or complex application interface. Distinguished from {deep magic}, which trades more on arcane *theoretical* knowledge. Writing device drivers is heavy wizardry; so is interfacing to {X} (sense 2) without a toolkit. Esp. found in comments similar to "Heavy wizardry begins here ...". Compare {voodoo programming}.

:heavyweight: adj. High-overhead; {baroque}; code-intensive; featureful, but costly. Esp. used of communication protocols, language designs, and any sort of implementation in which maximum generality and/or ease of implementation has been pushed at the expense of mundane considerations such as speed, memory utilization, and startup time. {EMACS} is a heavyweight editor; {X} is an *extremely* heavyweight window system. This term isn't pejorative, but one man's heavyweight is another's {elephantine} and a third's {monstrosity}. Oppose `lightweight'. Usage: now borders on techspeak, especially in the compound `heavyweight process'.

:heisenbug: /hi:'zen-buhg/ [from Heisenberg's Uncertainty Principle in quantum physics] n. A bug that disappears or alters its behavior when one attempts to probe or isolate it. Antonym of {Bohr bug}; see also {mandelbug}, {schroedinbug}. In C, nine out of ten heisenbugs result from either {fandango on core} phenomena (esp. lossage related to corruption of the malloc {arena}) or errors that {smash the stack}.

:Helen Keller mode: n. 1. State of a hardware or software system that is deaf, dumb, and blind, i.e., accepting no input and generating no output, usually due to an infinite loop or some other excursion into {deep space}. (Unfair to the real Helen Keller, whose success at learning speech was triumphant.) See also {go flatline}, {catatonic}. 2. On IBM PCs under DOS, refers to a specific failure mode in which a screen saver has kicked in over an {ill-behaved} application which bypasses the interrupts the screen saver watches for activity. Your choices are to try to get from the program's current state through a successful save-and-exit without being able to see what you're doing, or re-boot the machine. This isn't (strictly speaking) a crash.

:hello, sailor!: interj. Occasional West Coast equivalent of {hello, world}; seems to have originated at SAIL, later associated with the game {Zork} (which also included "hello, aviator" and "hello, implementor"). Originally from the traditional hooker's greeting to a swabbie fresh off the boat, of course.

:hello, wall!: excl. See {wall}.

:hello, world: interj. 1. The canonical minimal test message in the C/UNIX universe. 2. Any of the minimal programs that emit this message. Traditionally, the first program a C coder is supposed to write in a new environment is one that just prints "hello, world" to standard output (and indeed it is the first example program in {K&R}). Environments that generate an unreasonably large executable for this trivial test or which require a {hairy} compiler-linker invocation to generate it are considered to {lose} (see {X}). 3. Greeting uttered by a hacker making an entrance or requesting information from anyone present. "Hello, world! Is the {VAX} back up yet?"

:hex: n. 1. Short for {{hexadecimal}}, base 16. 2. A 6-pack of anything (compare {quad}, sense 2). Neither usage has anything to do with {magic} or {black art}, though the pun is appreciated and occasionally used by hackers. True story: As a joke, some hackers once offered some surplus ICs for sale to be worn as protective amulets against hostile magic. The chips were, of course, hex inverters.

:hexadecimal:: n. Base 16. Coined in the early 1960s to replace earlier `sexadecimal', which was too racy and amusing for stuffy IBM, and later adopted by the rest of the industry.

Actually, neither term is etymologically pure. If we take `binary' to be paradigmatic, the most etymologically correct term for base 10, for example, is `denary', which comes from `deni' (ten at a time, ten each), a Latin `distributive' number; the corresponding term for base-16 would be something like `sendenary'. `Decimal' is from an ordinal number; the corresponding prefix for 6 would imply something like `sextidecimal'. The `sexa-' prefix is Latin but incorrect in this context, and `hexa-' is Greek. The word `octal' is similarly incorrect; a correct form would be `octaval' (to go with decimal), or `octonary' (to go with binary). If anyone ever implements a base-3 computer, computer scientists will be faced with the unprecedented dilemma of a choice between two *correct* forms; both `ternary' and `trinary' have a claim to this throne.

:hexit: /hek'sit/ n. A hexadecimal digit (0--9, and A--F or a--f). Used by people who claim that there are only *ten* digits, dammit; sixteen-fingered human beings are rather rare, despite what some keyboard designs might seem to imply (see {space-cadet keyboard}).

:HHOK: See {ha ha only serious}.

:HHOS: See {ha ha only serious}.

:hidden flag: [scientific computation] n. An extra option added to a routine without changing the calling sequence. For example, instead of adding an explicit input variable to instruct a routine to give extra diagnostic output, the programmer might just add a test for some otherwise meaningless feature of the existing inputs, such as a negative mass. Liberal use of hidden flags can make a program very hard to debug and understand.

:high bit: [from `high-order bit'] n. 1. The most significant bit in a byte. 2. By extension, the most significant part of something other than a data byte: "Spare me the whole {saga}, just give me the high bit." See also {meta bit}, {hobbit}, {dread high-bit disease}, and compare the mainstream slang `bottom line'.

:high moby: /hi:' mohb'ee/ n. The high half of a 512K {PDP-10}'s physical address space; the other half was of course the low moby. This usage has been generalized in a way that has outlasted the {PDP-10}; for example, at the 1990 Washington D.C. Area Science Fiction Conclave (Disclave), when a miscommunication resulted in two separate wakes being held in commemoration of the shutdown of MIT's last {{ITS}} machines, the one on the upper floor was dubbed the `high moby' and the other the `low moby'. All parties involved {grok}ked this instantly. See {moby}.

:highly: [scientific computation] adv. The preferred modifier for overstating an understatement. As in: `highly nonoptimal', the worst possible way to do something; `highly nontrivial', either impossible or requiring a major research project; `highly nonlinear', completely erratic and unpredictable; `highly nontechnical', drivel written for {luser}s, oversimplified to the point of being misleading or incorrect (compare {drool-proof paper}). In other computing cultures, postfixing of {in the extreme} might be preferred.

:hing: // [IRC] n. Fortuitous typo for `hint', now in wide intentional use among players of {initgame}. Compare {newsfroup}, {filk}.

:hirsute: adj. Occasionally used humorously as a synonym for {hairy}.

:HLL: /H-L-L/ n. [High-Level Language (as opposed to assembler)] Found primarily in email and news rather than speech. Rarely, the variants `VHLL' and `MLL' are found. VHLL stands for `Very-High-Level Language' and is used to describe a {bondage-and-discipline language} that the speaker happens to like; Prolog and Backus's FP are often called VHLLs. `MLL' stands for `Medium-Level Language' and is sometimes used half-jokingly to describe {C}, alluding to its `structured-assembler' image. See also {languages of choice}.

:hobbit: n. 1. The High Order Bit of a byte; same as the {meta bit} or {high bit}. 2. The non-ITS name of [email protected] (*Hobbit*), master of lasers.

:hog: n.,vt. 1. Favored term to describe programs or hardware that seem to eat far more than their share of a system's resources, esp. those which noticeably degrade interactive response. *Not* used of programs that are simply extremely large or complex or that are merely painfully slow themselves (see {pig, run like a}). More often than not encountered in qualified forms, e.g., `memory hog', `core hog', `hog the processor', `hog the disk'. "A controller that never gives up the I/O bus gets killed after the bus-hog timer expires." 2. Also said of *people* who use more than their fair share of resources (particularly disk, where it seems that 10% of the people use 90% of the disk, no matter how big the disk is or how many people use it). Of course, once disk hogs fill up one filesystem, they typically find some other new one to infect, claiming to the sysadmin that they have an important new project to complete.

:holy wars: [from {USENET}, but may predate it] n. {flame war}s over {religious issues}. The paper by Danny Cohen that popularized the terms {big-endian} and {little-endian} in connection with the LSB-first/MSB-first controversy was entitled "On Holy Wars and a Plea for Peace". Other perennial Holy Wars have included {EMACS} vs. {vi}, my personal computer vs. everyone else's personal computer, {{ITS}} vs. {{UNIX}}, {{UNIX}} vs. {VMS}, {BSD} UNIX vs. {USG UNIX}, {C} vs. {{Pascal}}, {C} vs. {LISP}, etc., ad nauseam. The characteristic that distinguishes holy wars from normal technical disputes is that in a holy wars most of the participants spend their time trying to pass off personal value choices and cultural attachments as objective technical evaluations. See also {theology}.

:home box: n. A hacker's personal machine, especially one he or she owns. "Yeah? Well, *my* home box runs a full 4.2 BSD, so there!"

:hook: n. A software or hardware feature included in order to simplify later additions or changes by a user. For example, a simple program that prints numbers might always print them in base 10, but a more flexible version would let a variable determine what base to use; setting the variable to 5 would make the program print numbers in base 5. The variable is a simple hook. An even more flexible program might examine the variable and treat a value of 16 or less as the base to use, but treat any other number as the address of a user-supplied routine for printing a number. This is a {hairy} but powerful hook; one can then write a routine to print numbers as Roman numerals, say, or as Hebrew characters, and plug it into the program through the hook. Often the difference between a good program and a superb one is that the latter has useful hooks in judiciously chosen places. Both may do the original job about equally well, but the one with the hooks is much more flexible for future expansion of capabilities ({EMACS}, for example, is *all* hooks). The term `user exit' is synonymous but much more formal and less hackish.

:hop: n. One file transmission in a series required to get a file from point A to point B on a store-and-forward network. On such networks (including {UUCPNET} and {FidoNet}), the important inter-machine metric is the number of hops in the shortest path between them, rather than their geographical separation. See {bang path}.

:hose: 1. vt. To make non-functional or greatly degraded in performance. "That big ray-tracing program really hoses the system." See {hosed}. 2. n. A narrow channel through which data flows under pressure. Generally denotes data paths that represent performance bottlenecks. 3. n. Cabling, especially thick Ethernet cable. This is sometimes called `bit hose' or `hosery' (play on `hosiery') or `etherhose'. See also {washing machine}.

:hosed: adj. Same as {down}. Used primarily by UNIX hackers. Humorous: also implies a condition thought to be relatively easy to reverse. Probably derived from the Canadian slang `hoser' popularized by the Bob and Doug Mackenzie skits on SCTV. See {hose}. It is also widely used of people in the mainstream sense of `in an extremely unfortunate situation'.

Once upon a time, a Cray that had been experiencing periodic difficulties crashed, and it was announced to have been hosed. It was discovered that the crash was due to the disconnection of some coolant hoses. The problem was corrected, and users were then assured that everything was OK because the system had been rehosed. See also {dehose}.

:hot spot: n. 1. [primarily used by C/UNIX programmers, but spreading] It is received wisdom that in most programs, less than 10% of the code eats 90% of the execution time; if one were to graph instruction visits versus code addresses, one would typically see a few huge spikes amidst a lot of low-level noise. Such spikes are called `hot spots' and are good candidates for heavy optimization or {hand-hacking}. The term is especially used of tight loops and recursions in the code's central algorithm, as opposed to (say) initial set-up costs or large but infrequent I/O operations. See {tune}, {bum}, {hand-hacking}. 2. The active location of a cursor on a bit-map display. "Put the mouse's hot spot on the `ON' widget and click the left button." 3. A screen region that is sensitive to mouse clicks, which trigger some action. Hypertext help screens are an example, in which a hot spot exists in the vicinity of any word for which additional material is available. 4. In a massively parallel computer with shared memory, the one location that all 10,000 processors are trying to read or write at once (perhaps because they are all doing a {busy-wait} on the same lock).

:house wizard: [prob. from ad-agency lingo, `house freak'] n. A hacker occupying a technical-specialist, R&D, or systems position at a commercial shop. A really effective house wizard can have influence out of all proportion to his/her ostensible rank and still not have to wear a suit. Used esp. of UNIX wizards. The term `house guru' is equivalent.

:HP-SUX: /H-P suhks/ n. Unflattering hackerism for HP-UX, Hewlett-Packard's UNIX port, which eatures some truly unique bogosities in the filesystem internals and elsewhere (these occasionally create portability problems). HP-UX is often referred to as `hockey-pux' inside HP, and one respondent claims that the proper pronunciation is /H-P ukkkhhhh/ as though one were about to spit. Another such alternate spelling and pronunciation is "H-PUX" /H-puhks/. Hackers at HP/Apollo (the former Apollo Computers which was swallowed by HP in 1989) have been heard to complain that Mr. Packard should have pushed to have his name first, if for no other reason than the greater eloquence of the resulting acronym. Compare {AIDX}, {buglix}. See also {Nominal Semidestructor}, {Telerat}, {Open DeathTrap}, {ScumOS}, {sun-stools}, {terminak}.

:huff: v. To compress data using a Huffman code. Various programs that use such methods have been called `HUFF' or some variant thereof. Oppose {puff}. Compare {crunch}, {compress}.

:humma: // excl. A filler word used on various `chat' and `talk' programs when you had nothing to say but felt that it was important to say something. The word apparently originated (at least with this definition) on the MECC Timeshare System (MTS, a now-defunct educational time-sharing system running in Minnesota during the 1970s and the early 1980s) but was later sighted on early UNIX systems.

:Humor, Hacker:: n. A distinctive style of shared intellectual humor found among hackers, having the following marked characteristics:

1. Fascination with form-vs.-content jokes, paradoxes, and humor having to do with confusion of metalevels (see {meta}). One way to make a hacker laugh: hold a red index card in front of him/her with "GREEN" written on it, or vice-versa (note, however, that this is funny only the first time).