The Hacker's Dictionary by - (sneezy the snowman read aloud txt) 📕

commonly) assembler. 2. The art and science involved in comprehending a macrology in sense 1. Sometimes studying the macrology of a system is not unlike archeology, ecology, or {theology}, hence the sound-alike construction. See also {boxology}.

:macrotape: /ma'kroh-tayp/ n. An industry-standard reel of tape, as opposed to a {microtape}.

:maggotbox: /mag'*t-boks/ n. See {Macintrash}. This is even more derogatory.

:magic: adj. 1. As yet unexplained, or too complicated to explain; compare {automagically} and (Arthur C.) Clarke's Third Law: "Any sufficiently advanced technology is indistinguishable from magic." "TTY echoing is controlled by a large number of magic bits." "This routine magically computes the parity of an 8-bit byte in three instructions." 2. Characteristic of something that works although no one really understands why (this is especially called {black magic}). 3. [Stanford] A feature not generally publicized that allows something otherwise impossible, or a feature formerly in that category but now unveiled. Compare {black magic}, {wizardly}, {deep magic}, {heavy wizardry}.

For more about hackish magic', see {A Story AboutMagic'}

(in {appendix A}).

:magic cookie: [UNIX] n. 1. Something passed between routines or programs that enables the receiver to perform some operation; a capability ticket or opaque identifier. Especially used of small data objects that contain data encoded in a strange or intrinsically machine-dependent way. E.g., on non-UNIX OSes with a non-byte-stream model of files, the result of ftell(3)' may be a magic cookie rather than a byte offset; it can be passed tofseek(3)', but not operated on in any meaningful way. The phrase `it hands you a magic cookie' means it returns a result whose contents are not defined but which can be passed back to the same or some other program later. 2. An in-band code for changing graphic rendition (e.g., inverse video or underlining) or performing other control functions. Some older terminals would leave a blank on the screen corresponding to mode-change magic cookies; this was also called a {glitch}. See also {cookie}.

:magic number: [UNIX/C] n. 1. In source code, some non-obvious constant whose value is significant to the operation of a program and that is inserted inconspicuously in-line ({hardcoded}), rather than expanded in by a symbol set by a commented `#define'. Magic numbers in this sense are bad style. 2. A number that encodes critical information used in an algorithm in some opaque way. The classic examples of these are the numbers used in hash or CRC functions, or the coefficients in a linear congruential generator for pseudo-random numbers. This sense actually predates and was ancestral to the more common sense 1.

Special data located at the beginning of a binary data file to indicate its type to a utility. Under UNIX, the system and various applications programs (especially the linker) distinguish between types of executable file by looking for a magic number. Once upon a time, these magic numbers were PDP-11 branch instructions that skipped over header data to the start of executable code; the 0407, for example, was octal for `branch 16 bytes relative'. Nowadays only a {wizard} knows the spells to create magic numbers. How do you choose a fresh magic number of your own? Simple --- you pick one at random. See? It's magic!

:magic smoke: n. A substance trapped inside IC packages that enables them to function (also called blue smoke'; this is similar to the archaicphlogiston' hypothesis about combustion). Its existence is demonstrated by what happens when a chip burns up ---

the magic smoke gets let out, so it doesn't work any more. See {smoke test}, {let the smoke out}.

USENETter Jay Maynard tells the following story: "Once, while hacking on a dedicated Z80 system, I was testing code by blowing EPROMs and plugging them in the system, then seeing what happened.

One time, I plugged one in backwards. I only discovered that after I realized that Intel didn't put power-on lights under the quartz windows on the tops of their EPROMs --- the die was glowing white-hot. Amazingly, the EPROM worked fine after I erased it, filled it full of zeros, then erased it again. For all I know, it's still in service. Of course, this is because the magic smoke didn't get let out." Compare the original phrasing of {Murphy's Law}.

:mailing list: n. (often shortened in context to `list') 1. An {email} address that is an alias (or {macro}, though that word is never used in this connection) for many other email addresses.

Some mailing lists are simple reflectors', redirecting mail sent to them to the list of recipients. Others are filtered by humans or programs of varying degrees of sophistication; lists filtered by humans are said to bemoderated'. 2. The people who receive your email when you send it to such an address.

Mailing lists are one of the primary forms of hacker interaction, along with {USENET}. They predate USENET, having originated with the first UUCP and ARPANET connections. They are often used for private information-sharing on topics that would be too specialized for or inappropriate to public USENET groups. Though some of these maintain purely technical content (such as the Internet Engineering Task Force mailing list), others (like the `sf-lovers' list maintained for many years by Saul Jaffe) are recreational, and others are purely social. Perhaps the most infamous of the social lists was the eccentric bandykin distribution; its latter-day progeny, lectroids and tanstaafl, still include a number of the oddest and most interesting people in hackerdom.

Mailing lists are easy to create and (unlike USENET) don't tie up a significant amount of machine resources (until they get very large, at which point they can become interesting torture tests for mail software). Thus, they are often created temporarily by working groups, the members of which can then collaborate on a project without ever needing to meet face-to-face. Much of the material in this lexicon was criticized and polished on just such a mailing list (called `jargon-friends'), which included all the co-authors of Steele-1983.

:main loop: n. Software tools are often written to perform some actions repeatedly on whatever input is handed to them, terminating when there is no more input or they are explicitly told to go away.

In such programs, the loop that gets and processes input is called the `main loop'. See also {driver}.

:mainframe: n. Term originally referring to the cabinet containing the central processor unit or main frame' of a room-filling {Stone Age} batch machine. After the emergence of smallerminicomputer' designs in the early 1970s, the traditional {big iron} machines were described as `mainframe computers' and eventually just as mainframes. The term carries the connotation of a machine designed for batch rather than interactive use, though possibly with an interactive timesharing operating system retrofitted onto it; it is especially used of machines built by IBM, Unisys, and the other great {dinosaur}s surviving from computing's {Stone Age}.

It is common wisdom among hackers that the mainframe architectural tradition is essentially dead (outside of the tiny market for {number-crunching} supercomputers (see {cray})), having been swamped by the recent huge advances in IC technology and low-cost personal computing. As of 1991, corporate America hasn't quite figured this out yet, though the wave of failures, takeovers, and mergers among traditional mainframe makers are certainly straws in the wind (see {dinosaurs mating}).

:management: n. 1. Corporate power elites distinguished primarily by their distance from actual productive work and their chronic failure to manage (see also {suit}). Spoken derisively, as in "Management decided that ...". 2. Mythically, a vast bureaucracy responsible for all the world's minor irritations.

Hackers' satirical public notices are often signed The Mgt'; this derives from theIlluminatus' novels (see the Bibliography in {appendix C}).

:mandelbug: /mon'del-buhg/ [from the Mandelbrot set] n. A bug whose underlying causes are so complex and obscure as to make its behavior appear chaotic or even non-deterministic. This term implies that the speaker thinks it is a {Bohr bug}, rather than a {heisenbug}. See also {schroedinbug}.

:manged: /monjd/ [probably from the French manger' or Italianmangiare', to eat; perhaps influenced by English n. mange',mangy'] adj. Refers to anything that is mangled or damaged, usually beyond repair. "The disk was manged after the electrical storm." Compare {mung}.

:mangle: vt. Used similarly to {mung} or {scribble}, but more violent in its connotations; something that is mangled has been irreversibly and totally trashed.

:mangler: [DEC] n. A manager. Compare {mango}; see also {management}. Note that {system mangler} is somewhat different in connotation.

:mango: /mang'go/ [orig. in-house jargon at Symbolics] n. A manager.

Compare {mangler}. See also {devo} and {doco}.

:manularity: [prob. fr. techspeak granularity' +manual']

n. A notional measure of the manual labor required for some task, particularly one of the sort that automation is supposed to eliminate. "Composing English on paper has much higher manularity than using a text editor, especially in the revising stage."

Hackers tend to consider manularity a symptom of primitive methods; in fact, a true hacker confronted with an apparent requirement to do a computing task {by hand} will usually consider it motivation enough to build another tool.

:marbles: [from mainstream "lost all his/her marbles"] pl.n. The minimum needed to build your way further up some hierarchy of tools or abstractions. After a bad system crash, you need to determine if the machine has enough marbles to come up