Q-bit. In X.25 communications, the bit in a data packet that can be set by the sending DTE to qualify the user data in some way that is meaningful to the receiving DTE.
qdaemon. The daemon process that maintains a list of outstanding jobs and sends them to the specified device at the appropriate time.
QLLC. See qualified logical link control.
qualified class name. Any class name or class name qualified with one or more :: (scope) operators.
qualified expression. In Ada language, an expression preceded by an indication of its type or subtype. Such qualification is used when, in its absence, the expression might be ambiguous (for example as a consequence of overloading).
qualified logical link control (QLLC). A data link control protocol that enables SNA-to-SNA communications over an X.25 network.
qualified name. (1.) A name made unique by the addition of one or more qualifiers. (2.) A data name explicitly accompanied by a specification of the class to which it belongs in a specified classification system. (3.) In C++, used to qualify a nonclass type name such as a member by its class name.
qualified type name. Used to reduce complex class name syntax by using typedefs to represent qualified class names.
qualifier. (1.) A unique name used to identify another name. (2.)A modifier that makes a name unique. (3.) All names in a qualified name other than the rightmost, which is called the simple name.
qualifier bit. See Q-bit.
quality of service negotiation. An optional CCITT-specified facility.
quantization. The subdivision of the range of values of a variable into a finite number of nonoverlapping, but not necessarily equal intervals. Each interval is represented by an assigned value.
quantum. A subrange in quantization.
quark. In Enhanced X-Windows, synonym for string.
query. (1.) The action of searching data for desired information. (2.) In data communications, the process by which a master station asks a slave station to identify itself and to give its status. (3.) In interactive systems, an operation at a workstation that elicits a response from the system. (4.) A request for information from a file based on specific conditions.
queue. (1.) A line or list formed by items waiting to be processed. (2.) To form or arrange in a queue.
queue device. A logical device defining characteristics of a physical device attached to a queue.
queue element. A block of data or an item in a queue.
queue stanza. Defines a queue for one or more devices to which jobs can be queued.
queued I/O devices. Devices (keyboard, mouse, button, dials) whose changes are recorded in the event queue.
quiet system. A system on which no processes are running other than the process whose performance is being timed, and from which all communications devices have been disconnected.
quit. A key, command, or action that tells the system to return to a previous state or stop a process.
quote. To mask the special meaning of certain characters, causing the characters to be taken literally.
QWERTY keyboard. A keyboard having the standard keyboard layout. The term is derived from the sequence of the first six keys in the first row of alphabetic keys. See also AZERTY keyboard.