The New Hacker's Dictionary

(A closely related phenomenon, with a slightly different intent, is the habit manufacturers have of inventing new screw heads so that only Designated Persons, possessing the magic screwdrivers, can remove covers and make repairs or install options. A good 1990s example is the use of Torx screws for cable-TV set-top boxes. Older Apple Macintoshes took this one step further, requiring not only a long Torx screwdriver but a specialized case-cracking tool to open the box.)

In these latter days of open-systems computing this term has fallen somewhat into disuse, to be replaced by the observation that "Standards are great! There are so many of them to choose from!" Compare backward combatability.

cons /konz/ or /kons/

[from LISP]

1. vt. To add a new element to a specified list, esp. at the top. "OK, cons picking a replacement for the console TTY onto the agenda."

2. 'cons up': vt. To synthesize from smaller pieces: "to cons up an example".

In LISP itself, cons is the most fundamental operation for building structures. It takes any two objects and returns a 'dot-pair' or two-branched tree with one object hanging from each branch. Because the result of a cons is an object, it can be used to build binary trees of any shape and complexity. Hackers think of it as a sort of universal constructor, and that is where the jargon meanings spring from.

considered harmful // adj.

[very common] Edsger W. Dijkstra's note in the March 1968 "Communications of the ACM", "Goto Statement Considered Harmful", fired the first salvo in the structured programming wars (text at http://www.acm.org/classics). Amusingly, the ACM considered the resulting acrimony sufficiently harmful that it will (by policy) no longer print an article taking so assertive a position against a coding practice. (Years afterwards, a contrary view was uttered in a CACM letter called, inevitably, "'Goto considered harmful' considered harmful'"'. In the ensuing decades, a large number of both serious papers and parodies have borne titles of the form "X considered Y". The structured-programming wars eventually blew over with the realization that both sides were wrong, but use of such titles has remained as a persistent minor in-joke (the 'considered silly' found at various places in this lexicon is related).

console // n.

1. The operator's station of a mainframe. In times past, this was a privileged location that conveyed godlike powers to anyone with fingers on its keys. Under Unix and other modern timesharing OSes, such privileges are guarded by passwords instead, and the console is just the tty the system was booted from. Some of the mystique remains, however, and it is traditional for sysadmins to post urgent messages to all users from the console (on Unix, /dev/console).