The New Hacker's Dictionary

maggotbox /mag'*t-boks/ n.

See Macintrash. This is even more derogatory.

magic //

1. adj. 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. adj. Characteristic of something that works although no one really understands why (this is especially called []black magic).

3. n. [Stanford] A feature not generally publicized that allows something otherwise impossible, or a feature formerly in that category but now unveiled.

4. n. The ultimate goal of all engineering & development, elegance in the extreme; from the first corollary to Clarke's Third Law: "Any technology distinguishable from magic is insufficiently advanced".

Parodies playing on these senses of the term abound; some have made their way into serious documentation, as when a MAGIC directive was described in the Control Card Reference for GCOS c.1978. For more about hackish 'magic', see Appendix A. Compare []black magic, wizardly, deep magic, heavy wizardry.

magic cookie // n.

[Unix; common]

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 to fseek(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 (see also cookie). Some older terminals would leave a blank on the screen corresponding to mode-change magic cookies; this was also called a glitch (or occasionally a 'turd'; compare mouse droppings). See also cookie.