back door n. A hole in the security of a system deliberately left in place by designers or maintainers. The motivation for such holes is not always sinister; some operating systems, for example, come out of the box with privileged accounts intended for use by field service technicians or the vendor's maintenance programmers. Syn. trap door; may also be called a `wormhole'. See also iron box, cracker, worm, logic bomb. Historically, back doors have often lurked in systems longer than anyone expected or planned, and a few have become widely known. The infamous RTM worm of late 1988, for example, used a back door in the BSD UNIX `sendmail(8)' utility.
Ken Thompson's 1983 Turing Award lecture to the ACM revealed the existence of a back door in early UNIX versions that may have qualified as the most fiendishly clever security hack of all time. The C compiler contained code that would recognize when the `login' command was being recompiled and insert some code recognizing a password chosen by Thompson, giving him entry to the system whether or not an account had been created for him.
Normally such a back door could be removed by removing it from the source code for the compiler and recompiling the compiler. But to recompile the compiler, you have to *use* the compiler --- so Thompson also arranged that the compiler would *recognize when it was compiling a version of itself*, and insert into the recompiled compiler the code to insert into the recompiled `login' the code to allow Thompson entry --- and, of course, the code to recognize itself and do the whole thing again the next time around! And having done this once, he was then able to recompile the compiler from the original sources; the hack perpetuated itself invisibly, leaving the back door in place and active but with no trace in the sources.
The talk that revealed this truly moby hack was published as "Reflections on Trusting Trust", "Communications of the ACM 27", 8 (August 1984), pp. 761--763.
backbone cabal n. A group of large-site administrators who pushed through the Great Renaming and reined in the chaos of USENET during most of the 1980s. The cabal mailing list disbanded in late 1988 after a bitter internal catfight.
backbone site n. A key USENET and email site; one that processes a large amount of third-party traffic, especially if it is the home site of any of the regional coordinators for the USENET maps. Notable backbone sites as of early 1993 include uunet and the mail machines at Rutgers University, UC Berkeley, DEC's Western Research Laboratories, Ohio State University, and the University of Texas. Compare rib site, leaf site.
backgammon See bignum (sense 3), moby (sense 4), and pseudoprime.
background n.,adj.,vt. To do a task `in background' is to do it whenever foreground matters are not claiming your undivided attention, and `to background' something means to relegate it to a lower priority. "For now, we'll just print a list of nodes and links; I'm working on the graph-printing problem in background." Note that this implies ongoing activity but at a reduced level or in spare time, in contrast to mainstream `back burner' (which connotes benign neglect until some future resumption of activity). Some people prefer to use the term for processing that they have queued up for their unconscious minds (a tack that one can often fruitfully take upon encountering an obstacle in creative work). Compare amp off, slopsucker.
Technically, a task running in background is detached from the terminal where it was started (and often running at a lower priority); oppose foreground. Nowadays this term is primarily associated with UNIX, but it appears to have been first used in this sense on OS/360.
backspace and overstrike interj. Whoa! Back up. Used to suggest that someone just said or did something wrong. Common among APL programmers.
backward combatability /bak'w*rd k*m-bat'*-bil'*-tee/ [from `backward compatibility'] n. A property of hardware or software revisions in which previous protocols, formats, layouts, etc. are irrevocably discarded in favor of `new and improved' protocols, formats, and layouts, leaving the previous ones not merely deprecated but actively defeated. (Too often, the old and new versions cannot definitively be distinguished, such that lingering instances of the previous ones yield crashes or other infelicitous effects, as opposed to a simple "version mismatch" message.) A backwards compatible change, on the other hand, allows old versions to coexist without crashes or error messages, but too many major changes incorporating elaborate backwards compatibility processing can lead to extreme software bloat. See also flag day.
BAD /B-A-D/ [IBM: acronym, `Broken As Designed'] adj. Said of a program that is bogus because of bad design and misfeatures rather than because of bugginess. See working as designed.
Bad Thing [from the 1930 Sellar & Yeatman parody "1066 And All That"] n. Something that can't possibly result in improvement of the subject. This term is always capitalized, as in "Replacing all of the 9600-baud modems with bicycle couriers would be a Bad Thing". Oppose Good Thing. British correspondents confirm that Bad Thing and Good Thing (and prob. therefore Right Thing and Wrong Thing) come from the book referenced in the etymology, which discusses rulers who were Good Kings but Bad Things. This has apparently created a mainstream idiom on the British side of the pond.
bag on the side n. An extension to an established hack that is supposed to add some functionality to the original. Usually derogatory, implying that the original was being overextended and should have been thrown away, and the new product is ugly, inelegant, or bloated. Also v. phrase, `to hang a bag on the side [of]'. "C++? That's just a bag on the side of C ...." "They want me to hang a bag on the side of the accounting system."
bagbiter /bag'bi:t-*r/ n. 1. Something, such as a program or a computer, that fails to work, or works in a remarkably clumsy manner. "This text editor won't let me make a file with a line longer than 80 characters! What a bagbiter!" 2. A person who has caused you some trouble, inadvertently or otherwise, typically by failing to program the computer properly. Synonyms: loser, cretin, chomper. 3. `bite the bag' vi. To fail in some manner. "The computer keeps crashing every five minutes." "Yes, the disk controller is really biting the bag." The original loading of these terms was almost undoubtedly obscene, possibly referring to the scrotum, but in their current usage they have become almost completely sanitized.
ITS's lexiphage program is the first and to date only known example of a program *intended* to be a bagbiter.
bagbiting adj. Having the quality of a bagbiter. "This bagbiting system won't let me compute the factorial of a negative number." Compare losing, cretinous, bletcherous, `barfucious' (under barfulous) and `chomping' (under chomp).
bamf /bamf/
banana label n. The labels often used on the sides of macrotape reels, so called because they are shaped roughly like blunt-ended bananas. This term, like macrotapes themselves, is still current but visibly headed for obsolescence.
banana problem n. [from the story of the little girl who said "I know how to spell `banana', but I don't know when to stop"]. Not knowing where or when to bring a production to a close (compare fencepost error). One may say `there is a banana problem' of an algorithm with poorly defined or incorrect termination conditions, or in discussing the evolution of a design that may be succumbing to featuritis (see also creeping elegance, creeping featuritis). See item 176 under HAKMEM, which describes a banana problem in a Dissociated Press implementation. Also, see one-banana problem for a superficially similar but unrelated usage.
bandwidth n.
bang on vt. To stress-test a piece of hardware or software: "I banged on the new version of the simulator all day yesterday and it didn't crash once. I guess it is ready for release." The term pound on is synonymous.
bang path n. An old-style UUCP electronic-mail address specifying hops to get from some assumed-reachable location to the addressee, so called because each hop is signified by a bang sign. Thus, for example, the path ...!bigsite!foovax!barbox!me directs people to route their mail to machine bigsite (presumably a well-known location accessible to everybody) and from there through the machine foovax to the account of user me on barbox.
In the bad old days of not so long ago, before autorouting mailers became commonplace, people often published compound bang addresses using the { } convention (see glob) to give paths from *several* big machines, in the hopes that one's correspondent might be able to get mail to one of them reliably (example: ...!{seismo, ut-sally, ihnp4}!rice!beta!gamma!me). Bang paths of 8 to 10 hops were not uncommon in 1981. Late-night dial-up UUCP links would cause week-long transmission times. Bang paths were often selected by both transmission time and reliability, as messages would often get lost. See Internet Address, network, the, and sitename.
banner n.
bar /bar/ n.
bare metal n.
In the world of personal computing, bare metal programming (especially in sense 1 but sometimes also in sense 2) is often considered a Good Thing, or at least a necessary evil (because these machines have often been sufficiently slow and poorly designed to make it necessary; see ill-behaved). There, the term usually refers to bypassing the BIOS or OS interface and writing the application to directly access device registers and machine addresses. "To get 19.2 kilobaud on the serial port, you need to get down to the bare metal." People who can do this sort of thing well are held in high regard.
barf /barf/ [from mainstream slang meaning `vomit']
barfmail n. Multiple bounce messages accumulating to the level of serious annoyance, or worse. The sort of thing that happens when an inter-network mail gateway goes down or wonky.
barfulation /bar`fyoo-lay'sh*n/ interj. Variation of barf used around the Stanford area. An exclamation, expressing disgust. On seeing some particularly bad code one might exclaim, "Barfulation! Who wrote this, Quux?"
barfulous /bar'fyoo-l*s/ adj. (alt. `barfucious', /bar-fyoo-sh*s/) Said of something that would make anyone barf, if only for esthetic reasons.
barney n. In Commonwealth hackish, `barney' is to fred (sense #1) as bar is to foo. That is, people who commonly use `fred' as their first metasyntactic variable will often use `barney' second. The reference is, of course, to Fred Flintstone and Barney Rubble in the Flintstones cartoons.
baroque adj. Feature-encrusted; complex; gaudy; verging on excessive. Said of hardware or (esp.) software designs, this has many of the connotations of elephantine or monstrosity but is less extreme and not pejorative in itself. "Metafont even has features to introduce random variations to its letterform output. Now *that* is baroque!" See also rococo.
BASIC [acronym, from Beginner's All-purpose Symbolic Instruction Code] n. A programming language, originally designed for Dartmouth's experimental timesharing system in the early 1960s, which has since become the leading cause of brain-damage in proto-hackers. This is another case (like Pascal) of the cascading lossage that happens when a language deliberately designed as an educational toy gets taken too seriously. A novice can write short BASIC programs (on the order of 10--20 lines) very easily; writing anything longer is (a) very painful, and (b) encourages bad habits that will make it harder to use more powerful languages well. This wouldn't be so bad if historical accidents hadn't made BASIC so common on low-end micros. As it is, it ruins thousands of potential wizards a year.
batch adj.
bathtub curve n. Common term for the curve (resembling an end-to-end section of one of those claw-footed antique bathtubs) that describes the expected failure rate of electronics with time: initially high, dropping to near 0 for most of the system's lifetime, then rising again as it `tires out'. See also burn-in period, infant mortality.
baud /bawd/ [simplified from its technical meaning] n. Bits per second. Hence kilobaud or Kbaud, thousands of bits per second. The technical meaning is `level transitions per second'; this coincides with bps only for two-level modulation with no framing or stop bits. Most hackers are aware of these nuances but blithely ignore them.
Historical note: `baud' was originally a unit of telegraph signalling speed, set at one pulse per second. It was proposed at the International Telegraph Conference of 1927, and named after J.M.E. Baudot (1845--1903), the French engineer who constructed the first successful teleprinter.
baud barf /bawd barf/ n. The garbage one gets on the monitor when using a modem connection with some protocol setting (esp. line speed) incorrect, or when someone picks up a voice extension on the same line, or when really bad line noise disrupts the connection. Baud barf is not completely random, by the way; hackers with a lot of serial-line experience can usually tell whether the device at the other end is expecting a higher or lower speed than the terminal is set to. *Really* experienced ones can identify particular speeds.
baz /baz/ n. 1. The third metasyntactic variable "Suppose we have three functions: FOO, BAR, and BAZ. FOO calls BAR, which calls BAZ...." (See also fum) 2. interj. A term of mild annoyance. In this usage the term is often drawn out for 2 or 3 seconds, producing an effect not unlike the bleating of a sheep; /baaaaaaz/. 3. Occasionally appended to foo to produce `foobaz'.
Earlier versions of this lexicon derived `baz' as a Stanford corruption of bar. However, Pete Samson (compiler of the TMRC lexicon) reports it was already current when he joined TMRC in 1958. He says "It came from "Pogo". Albert the Alligator, when vexed or outraged, would shout `Bazz Fazz!' or `Rowrbazzle!' The club layout was said to model the (mythical) New England counties of Rowrfolk and Bassex (Rowrbazzle mingled with (Norfolk/Suffolk/Middlesex/Essex)."
bboard /bee'bord/ [contraction of `bulletin board'] n.
BBS /B-B-S/ [abbreviation, `Bulletin Board System'] n. An electronic bulletin board system; that is, a message database where people can log in and leave broadcast messages for others grouped (typically) into topic groups. Thousands of local BBS systems are in operation throughout the U.S., typically run by amateurs for fun out of their homes on MS-DOS boxes with a single modem line each. Fans of USENET and Internet or the big commercial timesharing bboards such as CompuServe and GEnie tend to consider local BBSes the low-rent district of the hacker culture, but they serve a valuable function by knitting together lots of hackers and users in the personal-micro world who would otherwise be unable to exchange code at all. See also bboard.
beam [from Star Trek Classic's "Beam me up, Scotty!"] vt. To transfer softcopy of a file electronically; most often in combining forms such as `beam me a copy' or `beam that over to his site'. Compare blast, snarf, BLT.
beanie key [Mac users] n. See command key.
beep n.,v. Syn. feep. This term seems to be preferred among micro hobbyists.
beige toaster n. A Macintosh. See toaster; compare Macintrash, maggotbox.
bells and whistles [by analogy with the toyboxes on theater organs] n. Features added to a program or system to make it more flavorful from a hacker's point of view, without necessarily adding to its utility for its primary function. Distinguished from chrome, which is intended to attract users. "Now that we've got the basic program working, let's go back and add some bells and whistles." No one seems to know what distinguishes a bell from a whistle.
bells, whistles, and gongs n. A standard elaborated form of bells and whistles; typically said with a pronounced and ironic accent on the `gongs'.
benchmark [techspeak] n. An inaccurate measure of computer performance. "In the computer industry, there are three kinds of lies: lies, damn lies, and benchmarks." Well-known ones include Whetstone, Dhrystone, Rhealstone (see h), the Gabriel LISP benchmarks (see gabriel), the SPECmark suite, and LINPACK. See also machoflops, MIPS, smoke and mirrors.
Berkeley Quality Software adj. (often abbreviated `BQS') Term used in a pejorative sense to refer to software that was apparently created by rather spaced-out hackers late at night to solve some unique problem. It usually has nonexistent, incomplete, or incorrect documentation, has been tested on at least two examples, and core dumps when anyone else attempts to use it. This term was frequently applied to early versions of the `dbx(1)' debugger. See also Berzerkeley.
Note to British and Commonwealth readers: that's /berk'lee/, not /bark'lee/ as in British Received Pronunciation.
berklix /berk'liks/ n.,adj. [contraction of `Berkeley UNIX'] See BSD. Not used at Berkeley itself. May be more common among suits attempting to sound like cognoscenti than among hackers, who usually just say `BSD'.
Berzerkeley /b*r-zer'klee/ [from `berserk', via the name of a now-deceased record label] n. Humorous distortion of `Berkeley' used esp. to refer to the practices or products of the BSD UNIX hackers. See software bloat, Missed'Em-Five, Berkeley Quality Software.
Mainstream use of this term in reference to the cultural and political peculiarities of UC Berkeley as a whole has been reported from as far back as the 1960s.
beta /bay't*/, /be't*/ or (Commonwealth) /bee't*/ n.
Historical note: More formally, to beta-test is to test a pre-release (potentially unreliable) version of a piece of software by making it available to selected customers and users. This term derives from early 1960s terminology for product cycle checkpoints, first used at IBM but later standard throughout the industry. `Alpha Test' was the unit, module, or component test phase; `Beta Test' was initial system test. These themselves came from earlier A- and B-tests for hardware. The A-test was a feasibility and manufacturability evaluation done before any commitment to design and development. The B-test was a demonstration that the engineering model functioned as specified. The C-test (corresponding to today's beta) was the B-test performed on early samples of the production design.
BFI /B-F-I/ n. See brute force and ignorance. Also encountered in the variants `BFMI', `brute force and *massive* ignorance' and `BFBI' `brute force and bloody ignorance'.
bible n.
BiCapitalization n. The act said to have been performed on trademarks (such as PostScript, NeXT, NeWS, VisiCalc, FrameMaker, TK!solver, EasyWriter) that have been raised above the ruck of common coinage by nonstandard capitalization. Too many marketroid types think this sort of thing is really cute, even the 2,317th time they do it. Compare studlycaps.
BIFF /bif/ [USENET] n. The most famous pseudo, and the prototypical newbie. Articles from BIFF are characterized by all uppercase letters sprinkled liberally with bangs, typos, `cute' misspellings (EVRY BUDY LUVS GOOD OLD BIFF CUZ HE"S A K00L DOOD AN HE RITES REEL AWESUM THINGZ IN CAPITULL LETTRS LIKE THIS!!!), use (and often misuse) of fragments of talk mode abbreviations, a long sig block (sometimes even a doubled sig), and unbounded naivet'e. BIFF posts articles using his elder brother's VIC-20. BIFF's location is a mystery, as his articles appear to come from a variety of sites. However, BITNET seems to be the most frequent origin. The theory that BIFF is a denizen of BITNET is supported by BIFF's (unfortunately invalid) electronic mail address: BIFF@BIT.NET.
[1993: Now It Can Be Told! My spies inform me that BIFF was
originally created by Joe Talmadge biff /bif/ vt. To notify someone of incoming mail. From the
BSD utility `biff(1)', which was in turn named after a
friendly golden Labrador who used to chase frisbees in the halls at
UCB while 4.2BSD was in development (it had a well-known habit of
barking whenever the mailman came). No relation to
BIFF.
Big Gray Wall n. What faces a VMS user searching for
documentation. A full VMS kit comes on a pallet, the documentation
taking up around 15 feet of shelf space before the addition of
layered products such as compilers, databases, multivendor
networking, and programming tools. Recent (since VMS version 5)
DEC documentation comes with gray binders; under VMS version 4 the
binders were orange (`big orange wall'), and under version 3 they
were blue. See VMS. Often contracted to `Gray Wall'.
big iron n. Large, expensive, ultra-fast computers. Used generally
of number-crunching supercomputers such as Crays, but can include
more conventional big commercial IBMish mainframes. Term of
approval; compare heavy metal, oppose dinosaur.
Big Red Switch [IBM] n. The power switch on a computer, esp. the
`Emergency Pull' switch on an IBM mainframe or the power switch
on an IBM PC where it really is large and red. "This !@%$%
bitty box is hung again; time to hit the Big Red Switch."
Sources at IBM report that, in tune with the company's passion for
TLAs, this is often abbreviated as `BRS' (this has also
become established on FidoNet and in the PC clone world). It
is alleged that the emergency pull switch on an IBM 360/91 actually
fired a non-conducting bolt into the main power feed; the BRSes on
more recent mainframes physically drop a block into place so that
they can't be pushed back in. People get fired for pulling them,
especially inappropriately (see also molly-guard). Compare
power cycle, three-finger salute, 120 reset; see
also scram switch.
Big Room, the n. The extremely large room with the blue ceiling
and intensely bright light (during the day) or black ceiling with
lots of tiny night-lights (during the night) found outside all
computer installations. "He can't come to the phone right now,
he's somewhere out in the Big Room."
big win n. Serendipity. "Yes, those two physicists discovered
high-temperature superconductivity in a batch of ceramic that had
been prepared incorrectly according to their experimental schedule.
Small mistake; big win!" See win big.
big-endian [From Swift's "Gulliver's Travels" via the famous
paper "On Holy Wars and a Plea for Peace" by Danny Cohen,
USC/ISI IEN 137, dated April 1, 1980] adj.
bignum /big'nuhm/ [orig. from MIT MacLISP] n.
Sense 1 may require some explanation. Most computer languages
provide a kind of data called `integer', but such computer
integers are usually very limited in size; usually they must be
smaller than than 2^(31) (2,147,483,648) or (on a
bitty box) 2^(15) (32,768). If you want to work
with numbers larger than that, you have to use floating-point
numbers, which are usually accurate to only six or seven decimal
places. Computer languages that provide bignums can perform exact
calculations on very large numbers, such as 1000! (the factorial
of 1000, which is 1000 times 999 times 998 times ... times 2
times 1). For example, this value for 1000! was computed by the
MacLISP system using bignums:
bigot n. A person who is religiously attached to a particular
computer, language, operating system, editor, or other tool (see
religious issues). Usually found with a specifier; thus,
`cray bigot', `ITS bigot', `APL bigot', `VMS bigot',
`Berkeley bigot'. Real bigots can be distinguished from mere
partisans or zealots by the fact that they refuse to learn
alternatives even when the march of time and/or technology is
threatening to obsolete the favored tool. It is truly said "You
can tell a bigot, but you can't tell him much." Compare
weenie.
bit [from the mainstream meaning and `Binary digIT'] n.
"I just need one bit from you" is a polite way of indicating that
you intend only a short interruption for a question that can
presumably be answered yes or no.
A bit is said to be `set' if its value is true or 1, and
`reset' or `clear' if its value is false or 0. One speaks of
setting and clearing bits. To toggle or `invert' a bit is
to change it, either from 0 to 1 or from 1 to 0. See also
flag, trit, mode bit.
The term `bit' first appeared in print in the computer-science
sense in 1949, and seems to have been coined by early computer
scientist John Tukey. Tukey records that it evolved over a lunch
table as a handier alternative to `bigit' or `binit'.
bit bang n. Transmission of data on a serial line, when
accomplished by rapidly tweaking a single output bit, in software,
at the appropriate times. The technique is a simple loop with
eight OUT and SHIFT instruction pairs for each byte. Input is more
interesting. And full duplex (doing input and output at the same
time) is one way to separate the real hackers from the
wannabees.
Bit bang was used on certain early models of Prime computers,
presumably when UARTs were too expensive, and on archaic Z80 micros
with a Zilog PIO but no SIO. In an interesting instance of the
cycle of reincarnation, this technique is now (1991) coming
back into use on some RISC architectures because it consumes such
an infinitesimal part of the processor that it actually makes sense
not to have a UART.
bit bashing n. (alt. `bit diddling' or bit twiddling) Term
used to describe any of several kinds of low-level programming
characterized by manipulation of bit, flag, nybble,
and other smaller-than-character-sized pieces of data; these
include low-level device control, encryption algorithms, checksum
and error-correcting codes, hash functions, some flavors of
graphics programming (see bitblt), and assembler/compiler code
generation. May connote either tedium or a real technical
challenge (more usually the former). "The command decoding for
the new tape driver looks pretty solid but the bit-bashing for the
control registers still has bugs." See also bit bang,
mode bit.
bit bucket n.
This term is used purely in jest. It is based on the fanciful
notion that bits are objects that are not destroyed but only
misplaced. This appears to have been a mutation of an earlier term
`bit box', about which the same legend was current; old-time
hackers also report that trainees used to be told that when the CPU
stored bits into memory it was actually pulling them `out of the
bit box'. See also chad box.
Another variant of this legend has it that, as a consequence of the
`parity preservation law', the number of 1 bits that go to the bit
bucket must equal the number of 0 bits. Any imbalance results in
bits filling up the bit bucket. A qualified computer technician
can empty a full bit bucket as part of scheduled maintenance.
bit decay n. See bit rot. People with a physics background
tend to prefer this variant for the analogy with particle decay. See
also computron, quantum bogodynamics.
bit rot n. Also bit decay. Hypothetical disease the existence
of which has been deduced from the observation that unused programs
or features will often stop working after sufficient time has
passed, even if `nothing has changed'. The theory explains that
bits decay as if they were radioactive. As time passes, the
contents of a file or the code in a program will become
increasingly garbled.
There actually are physical processes that produce such effects
(alpha particles generated by trace radionuclides in ceramic chip
packages, for example, can change the contents of a computer memory
unpredictably, and various kinds of subtle media failures can
corrupt files in mass storage), but they are quite rare (and
computers are built with error-detecting circuitry to compensate
for them). The notion long favored among hackers that cosmic
rays are among the causes of such events turns out to be a myth;
see the cosmic rays entry for details.
The term software rot is almost synonymous. Software rot is
the effect, bit rot the notional cause.
bit-paired keyboard n. obs. (alt. `bit-shift keyboard') A
non-standard keyboard layout that seems to have originated with the
Teletype ASR-33 and remained common for several years on early
computer equipment. The ASR-33 was a mechanical device (see
EOU), so the only way to generate the character codes from
keystrokes was by some physical linkage. The design of the ASR-33
assigned each character key a basic pattern that could be modified
by flipping bits if the SHIFT or the CTRL key was pressed. In
order to avoid making the thing more of a Rube Goldberg kluge than
it already was, the design had to group characters that shared the
same basic bit pattern on one key.
Looking at the ASCII chart, we find:
When electronic terminals became popular, in the early 1970s, there
was no agreement in the industry over how the keyboards should be
laid out. Some vendors opted to emulate the Teletype keyboard,
while others used the flexibility of electronic circuitry to make
their product look like an office typewriter. These alternatives
became known as `bit-paired' and `typewriter-paired' keyboards. To
a hacker, the bit-paired keyboard seemed far more logical --- and
because most hackers in those days had never learned to touch-type,
there was little pressure from the pioneering users to adapt
keyboards to the typewriter standard.
The doom of the bit-paired keyboard was the large-scale
introduction of the computer terminal into the normal office
environment, where out-and-out technophobes were expected to use
the equipment. The `typewriter-paired' standard became universal,
`bit-paired' hardware was quickly junked or relegated to dusty
corners, and both terms passed into disuse.
bitblt /bit'blit/ n. [from BLT, q.v.]
BITNET /bit'net/ [acronym: Because It's Time NETwork] n.
Everybody's least favorite piece of the network (see network,
the). The BITNET hosts are a collection of IBM dinosaurs and
VAXen (the latter with lobotomized comm hardware) that communicate
using 80-character EBCDIC card images (see eighty-column
mind); thus, they tend to mangle the headers and text of
third-party traffic from the rest of the ASCII/RFC-822 world with
annoying regularity. BITNET is also notorious as the apparent home
of BIFF.
bits n.pl.
bitty box /bit'ee boks/ n.
bixie /bik'see/ n. Variant emoticons used on BIX (the Byte
Information eXchange). The smiley bixie is <@_@>, apparently
intending to represent two cartoon eyes and a mouth. A few others
have been reported.
black art n. A collection of arcane, unpublished, and (by
implication) mostly ad-hoc techniques developed for a particular
application or systems area (compare black magic). VLSI design
and compiler code optimization were (in their beginnings)
considered classic examples of black art; as theory developed they
became deep magic, and once standard textbooks had been written,
became merely heavy wizardry. The huge proliferation of formal
and informal channels for spreading around new computer-related
technologies during the last twenty years has made both the term
`black art' and what it describes less common than formerly. See
also voodoo programming.
black hole n. What a piece of email or netnews has fallen into if
it disappears mysteriously between its origin and destination sites
(that is, without returning a bounce message). "I think
there's a black hole at foovax!" conveys suspicion that site
foovax has been dropping a lot of stuff on the floor lately
(see drop on the floor). The implied metaphor of email as
interstellar travel is interesting in itself. Compare bit bucket.
black magic n. A technique that works, though nobody really
understands why. More obscure than voodoo programming, which
may be done by cookbook. Compare also black art, deep magic, and magic number (sense 2).
blargh /blarg/ [MIT] n. The opposite of ping, sense 5; an
exclamation indicating that one has absorbed or is emitting a
quantum of unhappiness. Less common than ping.
blat n.
bletch /blech/ [from Yiddish/German `brechen', to vomit, poss.
via comic-strip exclamation `blech'] interj. Term of disgust.
Often used in "Ugh, bletch". Compare barf.
bletcherous /blech'*-r*s/ adj. Disgusting in design or
function; esthetically unappealing. This word is seldom used of
people. "This keyboard is bletcherous!" (Perhaps the keys don't
work very well, or are misplaced.) See losing,
cretinous, bagbiting, bogus, and random. The
term bletcherous applies to the esthetics of the thing so
described; similarly for cretinous. By contrast, something
that is `losing' or `bagbiting' may be failing to meet
objective criteria. See also bogus and random, which
have richer and wider shades of meaning than any of the
above.
blinkenlights /blink'*n-li:tz/ n. Front-panel diagnostic lights
on a computer, esp. a dinosaur. Derives from the last word
of the famous blackletter-Gothic sign in mangled pseudo-German that
once graced about half the computer rooms in the English-speaking
world. One version ran in its entirety as follows:
blit /blit/ vt. 1. To copy a large array of bits from one part
of a computer's memory to another part, particularly when the
memory is being used to determine what is shown on a display
screen. "The storage allocator picks through the table and copies
the good parts up into high memory, and then blits it all back down
again." See bitblt, BLT, dd, cat, blast,
snarf. More generally, to perform some operation (such as
toggling) on a large array of bits while moving them. 2. Sometimes
all-capitalized as `BLIT': an early experimental bit-mapped
terminal designed by Rob Pike at Bell Labs, later commercialized as
the AT&T 5620. (The folk etymology from `Bell Labs Intelligent
Terminal' is incorrect. Its creators liked to claim that "Blit"
stood for the Bacon, Lettuce, and Interactive Tomato.)
blitter /blit'r/ n. A special-purpose chip or hardware system
built to perform blit operations, esp. used for fast
implementation of bit-mapped graphics. The Commodore Amiga and a
few other micros have these, but in 1991 the trend is away from
them (however, see cycle of reincarnation). Syn. raster blaster.
blivet /bliv'*t/ [allegedly from a World War II military term
meaning "ten pounds of manure in a five-pound bag"] n.
This term has other meanings in other technical cultures; among
experimental physicists and hardware engineers of various kinds it
seems to mean any random object of unknown purpose (similar to
hackish use of frob). It has also been used to describe an
amusing trick-the-eye drawing resembling a three-pronged fork that
appears to depict a three-dimensional object until one realizes
that the parts fit together in an impossible way.
BLOB [acronym, Binary Large OBject] n. Used by database people to
refer to any random large block of bits that needs to be stored in
a database, such as a picture or sound file. The essential point
about a BLOB is that it's an object that cannot be interpreted
within the database itself.
block [from process scheduling terminology in OS theory]
block transfer computations [from the television series
"Dr. Who"] n. Computations so fiendishly subtle and complex
that they could not be performed by machines. Used to refer to any
task that should be expressible as an algorithm in theory, but
isn't.
Bloggs Family, the n. An imaginary family consisting of Fred and
Mary Bloggs and their children. Used as a standard example in
knowledge representation to show the difference between extensional
and intensional objects. For example, every occurrence of "Fred
Bloggs" is the same unique person, whereas occurrences of
"person" may refer to different people. Members of the Bloggs
family have been known to pop up in bizarre places such as the DEC
Telephone Directory. Compare Mbogo, Dr. Fred.
blow an EPROM /bloh *n ee'prom/ v. (alt. `blast an EPROM',
`burn an EPROM') To program a read-only memory, e.g. for use
with an embedded system. This term arose because the programming
process for the Programmable Read-Only Memories (PROMs) that
preceded present-day Erasable Programmable Read-Only Memories
(EPROMs) involved intentionally blowing tiny electrical fuses on
the chip. The usage lives on (it's too vivid and expressive to
discard) even though the write process on EPROMs is
nondestructive.
blow away vt. To remove (files and directories) from permanent
storage, generally by accident. "He reformatted the wrong
partition and blew away last night's netnews." Oppose nuke.
blow out [prob. from mining and tunneling jargon] vi. Of
software, to fail spectacularly; almost as serious as
crash and burn.
See blow past, blow up, die horribly.
blow past vt. To blow out despite a safeguard. "The server blew
past the 5K reserve buffer."
blow up vi. 1. [scientific computation] To become unstable. Suggests
that the computation is diverging so rapidly that it will soon
overflow or at least go nonlinear. 2. Syn. blow out.
BLT /B-L-T/, /bl*t/ or (rarely) /belt/ n.,vt. Synonym for
blit. This is the original form of blit and the ancestor
of bitblt. It referred to any large bit-field copy or move
operation (one resource-intensive memory-shuffling operation done
on pre-paged versions of ITS, WAITS, and TOPS-10 was sardonically
referred to as `The Big BLT'). The jargon usage has outlasted the
PDP-10 BLock Transfer instruction from which BLT derives;
nowadays, the assembler mnemonic BLT almost always means
`Branch if Less Than zero'.
Blue Book n.
Blue Glue [IBM] n. IBM's SNA (Systems Network Architecture), an
incredibly losing and bletcherous communications protocol
widely favored at commercial shops that don't know any better. The
official IBM definition is "that which binds blue boxes
together." See fear and loathing. It may not be irrelevant
that Blue Glue is the trade name of a 3M product that is
commonly used to hold down the carpet squares to the removable
panel floors common in dinosaur pens. A correspondent at
U. Minn. reports that the CS department there has about 80 bottles
of the stuff hanging about, so they often refer to any messy work
to be done as `using the blue glue'.
blue goo n. Term for `police' nanobots intended to prevent
gray goo, denature hazardous waste, destroy pollution, put
ozone back into the stratosphere, prevent halitosis, and promote
truth, justice, and the American way, etc. See
nanotechnology.
blue wire [IBM] n. Patch wires added to circuit boards at the factory to
correct design or fabrication problems. These may be necessary if
there hasn't been time to design and qualify another board version.
Compare purple wire, red wire, yellow wire.
blurgle /bler'gl/ [Great Britain] n. Spoken metasyntactic variable,
to indicate some text that is obvious from context, or
which is already known. If several words are to be replaced,
blurgle may well be doubled or trebled. "To look for something in
several files use `grep string blurgle blurgle'." In each case,
"blurgle blurgle" would be understood to be replaced by the file
you wished to search. Compare mumble, sense 7.
BNF /B-N-F/ n.
boa [IBM] n. Any one of the fat cables that lurk under the floor
in a dinosaur pen. Possibly so called because they display a
ferocious life of their own when you try to lay them straight and
flat after they have been coiled for some time. It is rumored
within IBM that channel cables for the 370 are limited to 200 feet
because beyond that length the boas get dangerous --- and it is
worth noting that one of the major cable makers uses the trademark
`Anaconda'.
board n. boat anchor n.
BOF /B-O-F/ or /bof/ n. Abbreviation for the phrase "Birds
Of a Feather" (flocking together), an informal discussion group
and/or bull session scheduled on a conference program. It is not
clear where or when this term originated, but it is now associated
with the USENIX conferences for UNIX techies and was already
established there by 1984. It was used earlier than that at DECUS
conferences and is reported to have been common at SHARE meetings
as far back as the early 1960s.
bogo-sort /boh`goh-sort'/ n. (var. `stupid-sort') The
archetypical perversely awful algorithm (as opposed to bubble sort, which is merely the generic *bad* algorithm).
Bogo-sort is equivalent to repeatedly throwing a deck of cards in
the air, picking them up at random, and then testing whether they
are in order. It serves as a sort of canonical example of
awfulness. Looking at a program and seeing a dumb algorithm, one
might say "Oh, I see, this program uses bogo-sort." Compare
bogus, brute force, Lasherism.
bogometer /boh-gom'-*t-er/ n. A notional instrument for
measuring bogosity. Compare the `wankometer' described in
the wank entry; see also bogus.
bogon /boh'gon/ [by analogy with proton/electron/neutron, but
doubtless reinforced after 1980 by the similarity to Douglas
Adams's `Vogons'; see the Bibliography in Appendix C] n.
The bogon has become the type case for a whole bestiary of nonce
particle names, including the `clutron' or `cluon' (indivisible
particle of cluefulness, obviously the antiparticle of the bogon)
and the futon (elementary particle of randomness, or sometimes
of lameness). These are not so much live usages in themselves as
examples of a live meta-usage: that is, it has become a standard
joke or linguistic maneuver to "explain" otherwise mysterious
circumstances by inventing nonce particle names. And these imply
nonce particle theories, with all their dignity or lack thereof (we
might note parenthetically that this is a generalization from
"(bogus particle) theories" to "bogus (particle theories)"!).
Perhaps such particles are the modern-day equivalents of trolls and
wood-nymphs as standard starting-points around which to construct
explanatory myths. Of course, playing on an existing word (as in
the `futon') yields additional flavor. Compare magic smoke.
bogon filter /boh'gon fil'tr/ n. Any device, software or hardware,
that limits or suppresses the flow and/or emission of bogons.
"Engineering hacked a bogon filter between the Cray and
the VAXen, and now we're getting fewer dropped packets." See
also bogosity, bogus.
bogon flux /boh'gon fluhks/ n. A measure of a supposed field of
bogosity emitted by a speaker, measured by a bogometer;
as a speaker starts to wander into increasing bogosity a listener
might say "Warning, warning, bogon flux is rising". See
quantum bogodynamics.
bogosity /boh-go's*-tee/ n.
bogotify /boh-go't*-fi:/ vt. To make or become bogus. A
program that has been changed so many times as to become completely
disorganized has become bogotified. If you tighten a nut too hard
and strip the threads on the bolt, the bolt has become bogotified
and you had better not use it any more. This coinage led to the
notional `autobogotiphobia' defined as `the fear of becoming
bogotified'; but is not clear that the latter has ever been
`live' jargon rather than a self-conscious joke in jargon about
jargon. See also bogosity, bogus.
bogue out /bohg owt/ vi. To become bogus, suddenly and
unexpectedly. "His talk was relatively sane until somebody asked
him a trick question; then he bogued out and did nothing but
flame afterwards." See also bogosity, bogus.
bogus adj.
Astrology is bogus. So is a bolt that is obviously about to break.
So is someone who makes blatantly false claims to have solved a
scientific problem. (This word seems to have some, but not all, of
the connotations of random --- mostly the negative ones.)
It is claimed that `bogus' was originally used in the hackish sense
at Princeton in the late 1960s. It was spread to CMU and Yale by
Michael Shamos, a migratory Princeton alumnus. A glossary of bogus
words was compiled at Yale when the word was first popularized (see
autobogotiphobia under bogotify). The word spread into
hackerdom from CMU and MIT. By the early 1980s it was also
current in something like the hackish sense in West Coast teen
slang, and it had gone mainstream by 1985. A correspondent from
Cambridge reports, by contrast, that these uses of `bogus' grate on
British nerves; in Britain the word means, rather specifically,
`counterfeit', as in "a bogus 10-pound note".
Bohr bug /bohr buhg/ [from quantum physics] n. A repeatable
bug; one that manifests reliably under a possibly unknown but
well-defined set of conditions. Antonym of heisenbug; see also
mandelbug, schroedinbug.
boink /boynk/ [USENET: variously ascribed to the TV series
"Cheers" "Moonlighting", and "Soap"] bondage-and-discipline language A language (such as Pascal,
Ada, APL, or Prolog) that, though ostensibly general-purpose,
is designed so as to enforce an author's theory of `right
programming' even though said theory is demonstrably inadequate for
systems hacking or even vanilla general-purpose programming. Often
abbreviated `B&D'; thus, one may speak of things "having the
B&D nature". See Pascal; oppose languages of
choice.
bonk/oif /bonk/, /oyf/ interj. In the MUD community, it
has become traditional to express pique or censure by `bonking'
the offending person. Convention holds that one should acknowledge
a bonk by saying `oif!' and there is a myth to the effect that
failing to do so upsets the cosmic bonk/oif balance, causing much
trouble in the universe. Some MUDs have implemented special
commands for bonking and oifing. See also talk mode.
book titles There is a tradition in hackerdom of informally
tagging important textbooks and standards documents with the
dominant color of their covers or with some other conspicuous
feature of the cover. Many of these are described in this lexicon
under their own entries. See Aluminum Book, Blue Book,
Cinderella Book, Devil Book, Dragon Book, Green
Book, Orange Book, Pink-Shirt Book, Purple Book,
Red Book, Silver Book, White Book, Wizard Book,
Yellow Book, and bible; see also rainbow series.
boot [techspeak; from `by one's bootstraps'] v.,n. To load and
initialize the operating system on a machine. This usage is no
longer jargon (having passed into techspeak) but has given rise to
some derivatives that are still jargon.
The derivative `reboot' implies that the machine hasn't been down
for long, or that the boot is a bounce (sense 4) intended to
clear some state of wedgitude. This is sometimes used of
human thought processes, as in the following exchange: "You've
lost me." "OK, reboot. Here's the theory...."
This term is also found in the variants `cold boot' (from
power-off condition) and `warm boot' (with the CPU and all
devices already powered up, as after a hardware reset or software
crash).
Another variant: `soft boot', reinitialization of only part of a
system, under control of other software still running: "If
you're running the mess-dos emulator, control-alt-insert will
cause a soft-boot of the emulator, while leaving the rest of the
system running."
Opposed to this there is `hard boot', which connotes hostility
towards or frustration with the machine being booted: "I'll have
to hard-boot this losing Sun." "I recommend booting it
hard." One often hard-boots by performing a power cycle.
Historical note: this term derives from `bootstrap loader', a short
program that was read in from cards or paper tape, or toggled in
from the front panel switches. This program was always very short
(great efforts were expended on making it short in order to
minimize the labor and chance of error involved in toggling it in),
but was just smart enough to read in a slightly more complex
program (usually from a card or paper tape reader), to which it
handed control; this program in turn was smart enough to read the
application or operating system from a magnetic tape drive or disk
drive. Thus, in successive steps, the computer `pulled itself up
by its bootstraps' to a useful operating state. Nowadays the
bootstrap is usually found in ROM or EPROM, and reads the first
stage in from a fixed location on the disk, called the `boot
block'. When this program gains control, it is powerful enough to
load the actual OS and hand control over to it.
bottom feeder n. Syn. for slopsucker, derived from the
fishermen's and naturalists' term for finny creatures who subsist
on the primordial ooze.
bottom-up implementation n. Hackish opposite of the techspeak term
`top-down design'. It is now received wisdom in most
programming cultures that it is best to design from higher levels
of abstraction down to lower, specifying sequences of action in
increasing detail until you get to actual code. Hackers often find
(especially in exploratory designs that cannot be closely
specified in advance) that it works best to *build* things in
the opposite order, by writing and testing a clean set of primitive
operations and then knitting them together.
bounce v.
bounce message [UNIX] n. Notification message returned to sender
by a site unable to relay email to the intended Internet Address recipient or the next link in a bang path (see
bounce, sense 1). Reasons might include a nonexistent or
misspelled username or a down relay site. Bounce messages can
themselves fail, with occasionally ugly results; see
sorcerer's apprentice mode
and software laser. The terms `bounce
mail' and `barfmail' are also common.
boustrophedon [from a Greek word for turning like an ox while
plowing] n. An ancient method of writing using alternate
left-to-right and right-to-left lines. This term is actually
philologists' techspeak and typesetters' jargon. Erudite hackers
use it for an optimization performed by some computer typesetting
software and moving-head printers. The adverbial form
`boustrophedonically' is also found (hackers purely love
constructions like this).
box n.
boxed comments n. Comments (explanatory notes attached to program
instructions) that occupy several lines by themselves; so called
because in assembler and C code they are often surrounded by a box
in a style something like this:
Common variants of this style omit the asterisks in column 2 or add
a matching row of asterisks closing the right side of the box. The
sparest variant omits all but the comment delimiters themselves;
the `box' is implied. Oppose winged comments.
boxen /bok'sn/ [by analogy with VAXen] pl.n. Fanciful
plural of box often encountered in the phrase `UNIX boxen',
used to describe commodity UNIX hardware. The connotation is
that any two UNIX boxen are interchangeable.
boxology /bok-sol'*-jee/ n. Syn. ASCII Art. This term
implies a more restricted domain, that of box-and-arrow drawings.
"His report has a lot of boxology in it." Compare
macrology.
bozotic /boh-zoh'tik/ or /boh-zo'tik/ [from the name of a TV
clown even more losing than Ronald McDonald] adj. Resembling or
having the quality of a bozo; that is, clownish, ludicrously wrong,
unintentionally humorous. Compare wonky, demented. Note
that the noun `bozo' occurs in slang, but the mainstream
adjectival form would be `bozo-like' or (in New England)
`bozoish'.
BQS /B-Q-S/ adj. Syn. Berkeley Quality Software.
brain dump n. The act of telling someone everything one knows
about a particular topic or project. Typically used when someone
is going to let a new party maintain a piece of code. Conceptually
analogous to an operating system core dump in that it saves a
lot of useful state before an exit. "You'll have to
give me a brain dump on FOOBAR before you start your new job at
HackerCorp." See core dump (sense 4). At Sun, this is also
known as `TOI' (transfer of information).
brain fart n. The actual result of a braino, as opposed to
the mental glitch that is the braino itself. E.g., typing
`dir' on a UNIX box after a session with DOS.
brain-dead adj. Brain-damaged in the extreme. It tends to imply
terminal design failure rather than malfunction or simple
stupidity. "This comm program doesn't know how to send a break
--- how brain-dead!"
braino /bray'no/ n. Syn. for thinko. See also brain
fart.
branch to Fishkill [IBM: from the location of one of the
corporation's facilities] n. Any unexpected jump in a program that
produces catastrophic or just plain weird results. See jump off into never-never land, hyperspace.
bread crumbs n. Debugging statements inserted into a program that
emit output or log indicators of the program's state to a file
so you can see where it dies or pin down the cause of surprising
behavior. The term is probably a reference to the Hansel and Gretel
story from the Brothers Grimm; in several variants, a character
leaves a trail of bread crumbs so as not to get lost in the
woods.
break-even point n. in the process of implementing a new computer
language, the point at which the language is sufficiently effective
that one can implement the language in itself. That is, for a new
language called, hypothetically, FOOGOL, one has reached break-even
when one can write a demonstration compiler for FOOGOL in FOOGOL,
discard the original implementation language, and thereafter use
working versions of FOOGOL to develop newer ones. This is an
important milestone; see MFTL.
[Since this entry was first written, several correspondents have
reported that there actually was a compiler for a tiny Algol-like
language called Foogol floating around on various vaxen in the
early and mid-1980s. The above example may not, after all, be
hypothetical. -- ESR]
breath-of-life packet [XEROX PARC] n. An Ethernet packet that
contains bootstrap (see boot) code, periodically sent out
from a working computer to infuse the `breath of life' into any
computer on the network that has happened to crash. Machines
depending on such packets have sufficient hardware or firmware code
to wait for (or request) such a packet during the reboot process.
See also dickless workstation.
The notional `kiss-of-death packet', with a function
complementary to that of a breath-of-life packet, is recommended
for dealing with hosts that consume too many network resources.
Though `kiss-of-death packet' is usually used in jest, there is
at least one documented instance of an Internet subnet with limited
address-table slots in a gateway machine in which such packets were
routinely used to compete for slots, rather like Christmas shoppers
competing for scarce parking spaces.
bring X to its knees v. To present a machine, operating system,
piece of software, or algorithm with a load so extreme or
pathological that it grinds to a halt. "To bring a MicroVAX
to its knees, try twenty users running vi --- or four running
EMACS." Compare hog.
brittle adj. Said of software that is functional but easily
broken by changes in operating environment or configuration, or by
any minor tweak to the software itself. Also, any system that
responds inappropriately and disastrously to abnormal but expected
external stimuli; e.g., a file system that is usually totally
scrambled by a power failure is said to be brittle. This term is
often used to describe the results of a research effort that were
never intended to be robust, but it can be applied to commercially
developed software, which displays the quality far more often than
it ought to. Oppose robust.
broadcast storm n. An incorrect packet broadcast on a network that
causes most hosts to respond all at once, typically with wrong
answers that start the process over again. See network
meltdown.
brochureware n. Planned but non-existent product like
vaporware, but with the added implication that marketing is
actively selling and promoting it (they've printed brochures).
Brochureware is often deployed as a strategic weapon; the idea is
to con customers into not committing to an existing product of the
competition's. It is a safe bet that when a brochureware product
finally becomes real, it will be more expensive than and inferior
to the alternatives that had been available for years.
broken adj. 1. Not working properly (of programs). 2. Behaving
strangely; especially (when used of people) exhibiting extreme
depression.
broken arrow [IBM] n. The error code displayed on line 25 of a
3270 terminal (or a PC emulating a 3270) for various kinds of
protocol violations and "unexpected" error conditions (including
connection to a down computer). On a PC, simulated with
`->/_', with the two center characters overstruck.
Note: to appreciate this term fully, it helps to know that `broken
arrow' is also military jargon for an accident involving nuclear
weapons....
broket /broh'k*t/ or /broh'ket`/ [by analogy with `bracket': a
`broken bracket'] n. Either of the characters `<' and `>',
when used as paired enclosing delimiters. This word
originated as a contraction of the phrase `broken bracket', that
is, a bracket that is bent in the middle. (At MIT, and apparently
in the Real World as well, these are usually called angle brackets.)
Brooks's Law prov. "Adding manpower to a late software project
makes it later" --- a result of the fact that the expected
advantage from splitting work among N programmers is
O(N) (that is, proportional to N), but the complexity
and communications cost associated with coordinating and then
merging their work is O(N^2) (that is, proportional to the
square of N). The quote is from Fred Brooks, a manager of
IBM's OS/360 project and author of "The Mythical Man-Month"
(Addison-Wesley, 1975, ISBN 0-201-00650-2), an excellent early book
on software engineering. The myth in question has been most
tersely expressed as "Programmer time is fungible" and Brooks
established conclusively that it is not. Hackers have never
forgotten his advice; too often, management still does. See
also creationism, second-system effect,
optimism.
BRS /B-R-S/ n. Syn. Big Red Switch. This abbreviation is
fairly common on-line.
brute force adj. Describes a primitive programming style, one in
which the programmer relies on the computer's processing power
instead of using his or her own intelligence to simplify the
problem, often ignoring problems of scale and applying naive
methods suited to small problems directly to large ones. The term
can also be used in reference to programming style: brute-force
programs are written in a heavyhanded, tedious way, full of
repetition and devoid of any elegance or useful abstraction (see
also brute force and ignorance).
The canonical example of a brute-force algorithm is associated
with the `traveling salesman problem' (TSP), a classical
NP-hard problem: Suppose a person is in, say, Boston, and
wishes to drive to N other cities. In what order should the
cities be visited in order to minimize the distance travelled? The
brute-force method is to simply generate all possible routes and
compare the distances; while guaranteed to work and simple to
implement, this algorithm is clearly very stupid in that it
considers even obviously absurd routes (like going from Boston to
Houston via San Francisco and New York, in that order). For very
small N it works well, but it rapidly becomes absurdly
inefficient when N increases (for N = 15, there are
already 1,307,674,368,000 possible routes to consider, and for
N = 1000 --- well, see bignum). Sometimes,
unfortunately, there is no better general solution than brute
force. See also NP-.
A more simple-minded example of brute-force programming is finding
the smallest number in a large list by first using an existing
program to sort the list in ascending order, and then picking the
first number off the front.
Whether brute-force programming should actually be considered
stupid or not depends on the context; if the problem is not
terribly big, the extra CPU time spent on a brute-force solution
may cost less than the programmer time it would take to develop a
more `intelligent' algorithm. Additionally, a more intelligent
algorithm may imply more long-term complexity cost and bug-chasing
than are justified by the speed improvement.
Ken Thompson, co-inventor of UNIX, is reported to have uttered the
epigram "When in doubt, use brute force". He probably intended
this as a ha ha only serious, but the original UNIX kernel's
preference for simple, robust, and portable algorithms over
brittle `smart' ones does seem to have been a significant
factor in the success of that OS. Like so many other tradeoffs in
software design, the choice between brute force and complex,
finely-tuned cleverness is often a difficult one that requires both
engineering savvy and delicate esthetic judgment.
brute force and ignorance n. A popular design technique at many
software houses --- brute force coding unrelieved by any
knowledge of how problems have been previously solved in elegant
ways. Dogmatic adherence to design methodologies tends to
encourage this sort of thing. Characteristic of early larval
stage programming; unfortunately, many never outgrow it. Often
abbreviated BFI: "Gak, they used a bubble sort! That's
strictly from BFI." Compare bogosity.
BSD /B-S-D/ n. [abbreviation for `Berkeley System Distribution'] a
family of UNIX versions for the DEC VAX and PDP-11
developed by Bill Joy and others at Berzerkeley starting
around 1980, incorporating paged virtual memory, TCP/IP networking
enhancements, and many other features. The BSD versions (4.1, 4.2,
and 4.3) and the commercial versions derived from them (SunOS,
ULTRIX, and Mt. Xinu) held the technical lead in the UNIX world
until AT&T's successful standardization efforts after about 1986,
and are still widely popular. See UNIX, USG UNIX.
BUAF // [abbreviation, from alt.fan.warlord] n. Big
Ugly ASCII Font --- a special form of ASCII Art. Various
programs exist for rendering text strings into block, bloob, and
pseudo-script fonts in cells between four and six character cells
on a side; this is smaller than the letters generated by older
banner (sense 2) programs. These are sometimes used to render
one's name in a sig block, and are critically referred to as
`BUAF's. See warlording.
BUAG // [abbreviation, from alt.fan.warlord] n. Big Ugly
ASCII Graphic. Pejorative term for ugly ASCII ART, especially
as found in sig blocks. For some reason, mutations of the
head of Bart Simpson are particularly common in the least
imaginative sig blocks. See warlording.
bubble sort n. Techspeak for a particular sorting technique in
which pairs of adjacent values in the list to be sorted are
compared and interchanged if they are out of order; thus, list
entries `bubble upward' in the list until they bump into one with a
lower sort value. Because it is not very good relative to other
methods and is the one typically stumbled on by naive and
untutored programmers, hackers consider it the canonical
example of a naive algorithm. The canonical example of a really
*bad* algorithm is bogo-sort. A bubble sort might be used
out of ignorance, but any use of bogo-sort could issue only from
brain damage or willful perversity.
bucky bits /buh'kee bits/ n.
It has long been rumored that `bucky bits' were named for
Buckminster Fuller during a period when he was consulting at
Stanford. Actually, bucky bits were invented by Niklaus Wirth when
*he* was at Stanford in 1964--65; he first suggested the idea
of an EDIT key to set the 8th bit of an otherwise 7-bit ASCII
character. best-known). It seems that, unknown to Wirth, certain
Stanford hackers had privately nicknamed him `Bucky' after a
prominent portion of his dental anatomy, and this nickname
transferred to the bit. Bucky-bit commands were used in a number
of editors written at Stanford, including most notably TV-EDIT and
NLS.
The term spread to MIT and CMU early and is now in general use.
Ironically, Wirth himself remained unaware of its derivation for
nearly 30 years, until GLS dug up this history in early 1993! See
double bucky, quadruple bucky.
buffer overflow n. What happens when you try to stuff more data
into a buffer (holding area) than it can handle. This may be due
to a mismatch in the processing rates of the producing and
consuming processes (see overrun and firehose syndrome),
or because the buffer is simply too small to hold all the data that
must accumulate before a piece of it can be processed. For example,
in a text-processing tool that crunches a line at a time, a
short line buffer can result in lossage as input from a long
line overflows the buffer and trashes data beyond it. Good
defensive programming would check for overflow on each character
and stop accepting data when the buffer is full up. The term is
used of and by humans in a metaphorical sense. "What time did I
agree to meet you? My buffer must have overflowed." Or "If I
answer that phone my buffer is going to overflow." See also
spam, overrun screw.
bug n. An unwanted and unintended property of a program or piece
of hardware, esp. one that causes it to malfunction. Antonym of
feature. Examples: "There's a bug in the editor: it writes
things out backwards." "The system crashed because of a hardware
bug." "Fred is a winner, but he has a few bugs" (i.e., Fred is
a good guy, but he has a few personality problems).
Historical note: Admiral Grace Hopper (an early computing pioneer
better known for inventing COBOL) liked to tell a story in
which a technician solved a glitch in the Harvard Mark II
machine by pulling an actual insect out from between the contacts
of one of its relays, and she subsequently promulgated bug in
its hackish sense as a joke about the incident (though, as she was
careful to admit, she was not there when it happened). For many
years the logbook associated with the incident and the actual bug
in question (a moth) sat in a display case at the Naval Surface
Warfare Center (NSWC). The entire story, with a picture of the
logbook and the moth taped into it, is recorded in the "Annals
of the History of Computing", Vol. 3, No. 3 (July 1981),
pp. 285--286.
The text of the log entry (from September 9, 1947), reads "1545
Relay #70 Panel F (moth) in relay. First actual case of bug being
found". This wording establishes that the term was already
in use at the time in its current specific sense --- and Hopper
herself reports that the term `bug' was regularly applied to
problems in radar electronics during WWII.
Indeed, the use of `bug' to mean an industrial defect was already
established in Thomas Edison's time, and a more specific and rather
modern use can be found in an electrical handbook from 1896
("Hawkin's New Catechism of Electricity", Theo. Audel & Co.)
which says: "The term `bug' is used to a limited extent to
designate any fault or trouble in the connections or working of
electric apparatus." It further notes that the term is "said to
have originated in quadruplex telegraphy and have been transferred
to all electric apparatus."
The latter observation may explain a common folk etymology of the
term; that it came from telephone company usage, in which "bugs in
a telephone cable" were blamed for noisy lines. Though this
derivation seems to be mistaken, it may well be a distorted memory
of a joke first current among *telegraph* operators more than
a century ago!
Actually, use of `bug' in the general sense of a disruptive event
goes back to Shakespeare! In the first edition of Samuel Johnson's
dictionary one meaning of `bug' is "A frightful object; a
walking spectre"; this is traced to `bugbear', a Welsh term for
a variety of mythological monster which (to complete the circle)
has recently been reintroduced into the popular lexicon through
fantasy role-playing games.
In any case, in jargon the word almost never refers to insects.
Here is a plausible conversation that never actually happened:
"There is a bug in this ant farm!"
"What do you mean? I don't see any ants in it."
"That's the bug."
[There has been a widespread myth that the original bug was moved
to the Smithsonian, and an earlier version of this entry so
asserted. A correspondent who thought to check discovered that the
bug was not there. While investigating this in late 1990, your
editor discovered that the NSWC still had the bug, but had
unsuccessfully tried to get the Smithsonian to accept it --- and
that the present curator of their History of American Technology
Museum didn't know this and agreed that it would make a worthwhile
exhibit. It was moved to the Smithsonian in mid-1991, but due to
space and money constraints has not yet been exhibited. Thus, the
process of investigating the original-computer-bug bug fixed it in
an entirely unexpected way, by making the myth true! --- ESR]
bug-compatible adj. Said of a design or revision that has been
badly compromised by a requirement to be compatible with
fossils or misfeatures in other programs or (esp.)
previous releases of itself. "MS-DOS 2.0 used \ as a path
separator to be bug-compatible with some cretin's choice of / as an
option character in 1.0."
bug-for-bug compatible: n. Same as bug-compatible, with the
additional implication that much tedious effort went into ensuring
that each (known) bug was replicated.
buglix /buhg'liks/ n. Pejorative term referring to DEC's ULTRIX
operating system in its earlier *severely* buggy versions.
Still used to describe ULTRIX, but without nearly so much venom.
Compare AIDX, HP-SUX, Nominal Semidestructor,
Telerat, sun-stools.
bulletproof adj. Used of an algorithm or implementation
considered extremely robust; lossage-resistant; capable of
correctly recovering from any imaginable exception condition --- a
rare and valued quality. Syn. armor-plated.
bump vt. Synonym for increment. Has the same meaning as
C's ++ operator. Used esp. of counter variables, pointers, and
index dummies in `for', `while', and `do-while'
loops.
burble [from Lewis Carroll's "Jabberwocky"] v. Like flame,
but connotes that the source is truly clueless and ineffectual
(mere flamers can be competent). A term of deep contempt.
"There's some guy on the phone burbling about how he got a DISK
FULL error and it's all our comm software's fault." This
is mainstream slang in some parts of England.
buried treasure n. A surprising piece of code found in some
program. While usually not wrong, it tends to vary from crufty
to bletcherous, and has lain undiscovered only because it was
functionally correct, however horrible it is. Used sarcastically,
because what is found is anything *but* treasure. Buried
treasure almost always needs to be dug up and removed. "I just
found that the scheduler sorts its queue using bubble sort!
Buried treasure!"
burst page n. Syn. banner, sense 1.
busy-wait vi. Used of human behavior, conveys that the subject is
busy waiting for someone or something, intends to move instantly as
soon as it shows up, and thus cannot do anything else at the
moment. "Can't talk now, I'm busy-waiting till Bill gets off the
phone."
Technically, `busy-wait' means to wait on an event by
spinning through a tight or timed-delay loop that polls for
the event on each pass, as opposed to setting up an interrupt
handler and continuing execution on another part of the task. This
is a wasteful technique, best avoided on time-sharing systems where
a busy-waiting program may hog the processor.
buzz vi.
BWQ /B-W-Q/ [IBM: abbreviation, `Buzz Word Quotient'] The
percentage of buzzwords in a speech or documents. Usually roughly
proportional to bogosity. See TLA.
by hand adv.
byte /bi:t/ [techspeak] n. A unit of memory or data equal to
the amount used to represent one character; on modern architectures
this is usually 8 bits, but may be 9 on 36-bit machines. Some
older architectures used `byte' for quantities of 6 or 7 bits, and
the PDP-10 supported `bytes' that were actually bitfields of
1 to 36 bits! These usages are now obsolete, and even 9-bit bytes
have become rare in the general trend toward power-of-2 word sizes.
Historical note: The term was coined by Werner Buchholz in 1956
during the early design phase for the IBM Stretch computer;
originally it was described as 1 to 6 bits (typical I/O equipment
of the period used 6-bit chunks of information). The move to an
8-bit byte happened in late 1956, and this size was later adopted
and promulgated as a standard by the System/360. The word was
coined by mutating the word `bite' so it would not be
accidentally misspelled as bit. See also nybble.
bytesexual /bi:t`sek'shu-*l/ adj. Said of hardware, denotes
willingness to compute or pass data in either big-endian or
little-endian format (depending, presumably, on a mode bit
somewhere). See also NUXI Problem.
bzzzt, wrong /bzt rong/ [USENET/Internet] From a Robin Williams
routine in the movie "Dead Poets Society" spoofing radio or
TV quiz programs, such as *Truth or Consequences*, where an
incorrect answer earns one a blast from the buzzer and condolences
from the interlocutor. A way of expressing mock-rude disagreement,
usually immediately following an included quote from another
poster. The less abbreviated "*Bzzzzt*, wrong, but thank you for
playing" is also common; capitalization and emphasis of the
buzzer sound varies.
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high low bits
bits 0000 0001 0010 0011 0100 0101 0110 0111 1000 1001
010 ! " # $ % & ' ( )
011 0 1 2 3 4 5 6 7 8 9
This is why the characters !"#$%&'() appear where they do on a
Teletype (thankfully, they didn't use shift-0 for space). This was
*not* the weirdest variant of the QWERTY layout widely
seen, by the way; that prize should probably go to one of several
(differing) arrangements on IBM's even clunkier 026 and 029 card
punches.
ACHTUNG! ALLES LOOKENSPEEPERS! Das computermachine
ist nicht fuer gefingerpoken und mittengrabben. Ist easy schnappen
der springenwerk, blowenfusen und poppencorken mit spitzensparken.
Ist nicht fuer gewerken bei das dumpkopfen. Das rubbernecken
sichtseeren keepen das cotten-pickenen hans in das pockets muss;
relaxen und watchen das blinkenlichten.
This silliness dates back at least as far as 1959 at Stanford
University and had already gone international by the early 1960s,
when it was reported at London University's ATLAS computing site.
There are several variants of it in circulation, some of which
actually do end with the word `blinkenlights'.
In an amusing example of turnabout-is-fair-play, German hackers
have developed their own versions of the blinkenlights poster in
fractured English, one of which is reproduced here:
ATTENTION
This room is fullfilled mit special electronische equippment.
Fingergrabbing and pressing the cnoeppkes from the computers is
allowed for die experts only! So all the "lefthanders" stay away
and do not disturben the brainstorming von here working
intelligencies. Otherwise you will be out thrown and kicked
anderswhere! Also: please keep still and only watchen astaunished
the blinkenlights.
See also geef.
< postal-address > ::= < name-part> < street-address> < zip-part>
< personal-part> ::= < name> | < initial> "."
< name-part> ::= < personal-part> < last-name> [< jr-part> ] < EOL>
| < personal-part> < name-part>
< street-address> ::= [< apt> ] < house-num> < street-name> < EOL>
< zip-part> ::= < town-name> "," < state-code> < ZIP-code> < EOL>
This translates into English as: "A postal-address consists of a
name-part, followed by a street-address part, followed by a
zip-code part. A personal-part consists of either a first name or
an initial followed by a dot. A name-part consists of either: a
personal-part followed by a last name followed by an optional
`jr-part' (Jr., Sr., or dynastic number) and end-of-line, or a
personal part followed by a name part (this rule illustrates the
use of recursion in BNFs, covering the case of people who use
multiple first and middle names and/or initials). A street address
consists of an optional apartment specifier, followed by a street
number, followed by a street name. A zip-part consists of a
town-name, followed by a comma, followed by a state code, followed
by a ZIP-code followed by an end-of-line." Note that many things
(such as the format of a personal-part, apartment specifier, or
ZIP-code) are left unspecified. These are presumed to be obvious
from context or detailed somewhere nearby. See also parse.
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