:English: 1. n.,obs. The source code for a program, which may be in any language, as opposed to the linkable or executable binary produced from it by a compiler. The idea behind the term is that to a real hacker, a program written in his favorite programming language is at least as readable as English. Usage: used mostly by old-time hackers, though recognizable in context. 2. The official name of the database language used by the Pick Operating System, actually a sort of crufty, brain-damaged SQL with delusions of grandeur. The name permits {marketroid}s to say "Yes, and you can program our computers in English!" to ignorant {suit}s without quite running afoul of the truth-in-advertising laws.
:enhancement: n. {Marketroid}-speak for a bug {fix}. This abuse of language is a popular and time-tested way to turn incompetence into increased revenue. A hacker being ironic would instead call the fix a {feature} —- or perhaps save some effort by declaring the bug itself to be a feature.
:ENQ: /enkw/ or /enk/ [from the ASCII mnemonic ENQuire for 0000101] An on-line convention for querying someone's availability. After opening a {talk mode} connection to someone apparently in heavy hack mode, one might type `SYN SYN ENQ?' (the SYNs representing notional synchronization bytes), and expect a return of {ACK} or {NAK} depending on whether or not the person felt interruptible. Compare {ping}, {finger}, and the usage of `FOO?' listed under {talk mode}.
:EOF: /E-O-F/ [abbreviation, `End Of File'] n. 1. [techspeak] Refers esp. to whatever {out-of-band} value is returned by C's sequential character-input functions (and their equivalents in other environments) when end of file has been reached. This value is -1 under C libraries postdating V6 UNIX, but was originally 0. 2. [UNIX] The keyboard character (usually control-D, the ASCII EOT (End Of Transmission) character) which is mapped by the terminal driver into an end-of-file condition. 3. Used by extension in non-computer contexts when a human is doing something that can be modeled as a sequential read and can't go further. "Yeah, I looked for a list of 360 mnemonics to post as a joke, but I hit EOF pretty fast; all the library had was a {JCL} manual." See also {EOL}.
:EOL: /E-O-L/ [End Of Line] n. Syn. for {newline}, derived perhaps from the original CDC6600 Pascal. Now rare, but widely recognized and occasionally used for brevity. Used in the example entry under {BNF}. See also {EOF}.
:EOU: /E-O-U/ n. The mnemonic of a mythical ASCII control character (End Of User) that could make an ASR-33 Teletype explode on receipt. This parodied the numerous obscure delimiter and control characters left in ASCII from the days when it was associated more with wire-service teletypes than computers (e.g., FS, GS, RS, US, EM, SUB, ETX, and esp. EOT). It is worth remembering that ASR-33s were big, noisy mechanical beasts with a lot of clattering parts; the notion that one might explode was nowhere near as ridiculous as it might seem to someone sitting in front of a {tube} or flatscreen today.
:epoch: [UNIX: prob. from astronomical timekeeping] n. The time and date corresponding to 0 in an operating system's clock and timestamp values. Under most UNIX versions the epoch is 00:00:00 GMT, January 1, 1970; under VMS, it's 00:00:00 GMT of November 17, 1858 (base date of the U.S. Naval Observatory's ephemerides). System time is measured in seconds or {tick}s past the epoch. Weird problems may ensue when the clock wraps around (see {wrap around}), which is not necessarily a rare event; on systems counting 10 ticks per second, a signed 32-bit count of ticks is good only for 6.8 years. The 1-tick-per-second clock of UNIX is good only until January 18, 2038, assuming at least some software continues to consider it signed and that word lengths don't increase by then. See also {wall time}.
:epsilon: [see {delta}] 1. n. A small quantity of anything. "The cost is epsilon." 2. adj. Very small, negligible; less than {marginal}. "We can get this feature for epsilon cost." 3. `within epsilon of': close enough to be indistinguishable for all practical purposes. This is even closer than being `within delta of'. "That's not what I asked for, but it's within epsilon of what I wanted." Alternatively, it may mean not close enough, but very little is required to get it there: "My program is within epsilon of working."
:epsilon squared: n. A quantity even smaller than {epsilon}, as small in comparison to epsilon as epsilon is to something normal; completely negligible. If you buy a supercomputer for a million dollars, the cost of the thousand-dollar terminal to go with it is {epsilon}, and the cost of the ten-dollar cable to connect them is epsilon squared. Compare {lost in the underflow}, {lost in the noise}.
:era, the: Syn. {epoch}. Webster's Unabridged makes these words almost synonymous, but `era' usually connotes a span of time rather than a point in time. The {epoch} usage is recommended.