The Jargon File, Version 2.9.10, 01 Jul 1992. Various

is condescending, implying that the programmer is acting

       mindlessly rather than thinking carefully about what is required to

       integrate the code for two similar cases.

      :casters-up mode: [IBM] n. Yet another synonym for `broken' or `down'. Usually connotes a major failure. A system (hardware or software) which is `down' may be already being restarted before the failure is noticed, whereas one which is `casters up' is usually a good excuse to take the rest of the day off (as long as you're not responsible for fixing it).

      :casting the runes: n. What a {guru} does when you ask him or her to run a particular program and type at it because it never works for anyone else; esp. used when nobody can ever see what the guru is doing different from what J. Random Luser does. Compare {incantation}, {runes}, {examining the entrails}; also see the AI koan about Tom Knight in "{A Selection of AI Koans}" ({appendix A}).

      :cat: [from `catenate' via {{UNIX}} `cat(1)'] vt. 1. [techspeak] To spew an entire file to the screen or some other output sink without pause. 2. By extension, to dump large amounts of data at an unprepared target or with no intention of browsing it carefully. Usage: considered silly. Rare outside UNIX sites. See also {dd}, {BLT}.

      Among UNIX fans, `cat(1)' is considered an excellent example of user-interface design, because it outputs the file contents without such verbosity as spacing or headers between the files, and because it does not require the files to consist of lines of text, but works with any sort of data.

      Among UNIX-haters, `cat(1)' is considered the {canonical} example of *bad* user-interface design. This because it is more often used to {blast} a file to standard output than to concatenate two files. The name `cat' for the former operation is just as unintuitive as, say, LISP's {cdr}.

      Of such oppositions are {holy wars} made….

      :catatonic: adj. Describes a condition of suspended animation in which something is so {wedged} or {hung} that it makes no response. If you are typing on a terminal and suddenly the computer doesn't even echo the letters back to the screen as you type, let alone do what you're asking it to do, then the computer is suffering from catatonia (possibly because it has crashed). "There I was in the middle of a winning game of {nethack} and it went catatonic on me! Aaargh!" Compare {buzz}.

      :cd tilde: /see-dee til-d*/ vi. To go home. From the UNIX C-shell and Korn-shell command `cd ~', which takes one `$HOME'. By extension, may be used with other arguments; thus, over an electronic chat link, `cd ~coffee' would mean "I'm going to the coffee machine."

      :cdr: /ku'dr/ or /kuh'dr/ [from LISP] vt. To skip past the first item from a list of things (generalized from the LISP operation on binary tree structures, which returns a list consisting of all but the first element of its argument). In the form `cdr down', to trace down a list of elements: "Shall we cdr down the agenda?" Usage: silly. See also {loop through}.

      Historical note: The instruction format of the IBM 7090 that hosted

       the original LISP implementation featured two 15-bit fields called

       the `address' and `decrement' parts. The term `cdr' was originally

       `Contents of Decrement part of Register'. Similarly, `car' stood

       for `Contents of Address part of Register'.

      The cdr and car operations have since become bases for

       formation of compound metaphors in non-LISP contexts. GLS recalls,

       for example, a programming project in which strings were

       represented as linked lists; the get-character and skip-character

       operations were of course called CHAR and CHDR.

      :chad: /chad/ n. 1. The perforated edge strips on printer paper, after they have been separated from the printed portion. Also called {selvage} and {perf}. 2. obs. The confetti-like paper bits punched out of cards or paper tape; this was also called `chaff', `computer confetti', and `keypunch droppings'.

      Historical note: One correspondent believes `chad' (sense 2) derives from the Chadless keypunch (named for its inventor), which cut little u-shaped tabs in the card to make a hole when the tab folded back, rather than punching out a circle/rectangle; it was clear that if the Chadless keypunch didn't make them, then the stuff that other keypunches made had to be `chad'.

      :chad box: n. {Iron Age} card punches contained boxes inside them, about the size of a lunchbox (or in some models a large wastebasket), that held the {chad} (sense 2). You had to open the covers of the card punch periodically and empty the chad box. The {bit bucket} was notionally the equivalent device in the CPU enclosure, which was typically across the room in another great gray-and-blue box.

      :chain: 1. [orig. from BASIC's `CHAIN' statement] vi. To hand off execution to a child or successor without going through the {OS} command interpreter that invoked it. The state of the parent program is lost and there is no returning to it. Though this facility used to be common on memory-limited micros and is still widely supported for backward compatibility, the jargon usage is semi-obsolescent; in particular, most UNIX programmers will think of this as an {exec}. Oppose the more modern {subshell}. 2. A series of linked data areas within an operating system or application. `Chain rattling' is the process of repeatedly running through the linked data areas searching for one which is of interest to the executing program. The implication is that there is a very large number of links on the chain.

      :channel: [IRC] n. The basic unit of discussion on {IRC}. Once one joins a channel, everything one types is read by others on that channel. Channels can either be named with numbers or with strings that begin with a `#' sign, and can have topic descriptions (which are generally irrelevant to the actual subject of discussion). Some notable channels are `#initgame', `#hottub', and `#report'. At times of international crisis, `#report' has hundreds of members, some of whom take turns listening to various news services and summarizing the news, or in some cases, giving first-hand accounts of the action (e.g., Scud missile attacks in Tel Aviv during the Gulf War in 1991).

      :channel hopping: [IRC, GEnie] n. To rapidly switch channels on {IRC}, or GEnie chat board, just as a social butterfly might hop from one group to another at a party. This may derive from the TV watcher's idiom `channel surfing'.

      :channel op: /chan'l op/ [IRC] n. Someone who is endowed with privileges on a particular {IRC} channel; commonly abbreviated `chanop' or `CHOP'. These privileges include the right to {kick} users, to change various status bits, and to make others into CHOPs.

      :chanop: /chan'-op/ [IRC] n. See {channel op}.

      :char: /keir/ or /char/; rarely, /kar/ n. Shorthand for `character'. Esp. used by C programmers, as `char' is C's typename for character data.

      :charityware: /char'it-ee-weir`/ n. Syn. {careware}.

      :chase pointers: 1. vi. To go through multiple levels of indirection, as in traversing a linked list or graph structure. Used esp. by programmers in C, where explicit pointers are a very common data type. This is techspeak, but it remains jargon when used of human networks. "I'm chasing pointers. Bob said you could tell me who to talk to about…." See {dangling pointer} and {snap}. 2. [Cambridge] `pointer chase' or `pointer hunt': The process of going through a dump (interactively or on a large piece of paper printed with hex {runes}) following dynamic data-structures. Used only in a debugging context.

      :check: n. A hardware-detected error condition, most commonly used to refer to actual hardware failures rather than software-induced traps. E.g., a `parity check' is the result of a hardware-detected parity error. Recorded here because it's often humorously extended to non-technical problems. For example, the term `child check' has been used to refer to the problems caused by a small child who is curious to know what happens when s/he presses all the cute buttons on a computer's console (of course, this particular problem could have been prevented with {molly-guard}s).

      :chemist: [Cambridge] n. Someone who wastes computer time on {number-crunching} when you'd far rather the machine were doing something more productive, such as working out anagrams of your name or printing Snoopy calendars or running {life} patterns. May or may not refer to someone who actually studies chemistry.

      :Chernobyl