B‚zier curve -

(1) A mathematical technique of specifying smooth continuous lines and surfaces, which require a starting point and a finishing point with several intermediate points that influence or control the path of the linking curve. Named after Dr. P. B‚zier. (2) (D of C) In the AIX Graphics Library, a cubic spline approximation to a set of four control points that passes through the first and fourth control points and that has a continuous slope where two spline segments meet. Named after Dr. P. B‚zier.

(1) In multiprogramming, the conditions under which low-priority programs are executed. Contrast with foreground. (2) An active session that is not currently displayed on the screen.

The color in which the background of a graphic primitive is drawn.

An attribute that determines how the background of a graphic primitive is combined with the existing color of the graphics presentation space. Contrast with mix.

In multiprogramming, a program that executes with a low priority. Contrast with foreground program.

A representation in memory of the data displayed on an APA device, usually the screen.

(1) A string of data elements recorded or transmitted as a unit. The elements may be characters, words, or logical records. (T) (2) To record data in a block. (3) A collection of contiguous records recorded as a unit. Blocks are separated by interblock gaps and each block may contain one or more records. (A)

A storage device that performs I/O operations on blocks of data called sectors. Data on block devices can be randomly accessed. Block devices are designated by a drive letter (for example, C:).

A condition set by an application that determines when its threads might block. For example, an application might set the Pipemode parameter for the DosCreateNPipe function so that its threads perform I/O operations to the named pipe block when no data is available.

A visual indication (for example, a separator line or a background color) of the boundaries of a window.

An operation used to compute the size of the smallest rectangle that encloses a graphics object on the screen.

(1) A point in a computer program where execution may be halted. A breakpoint is usually at the beginning of an instruction where halts, caused by external intervention, are convenient for resuming execution. (T) (2) A place in a program, specified by a command or a condition, where the system halts execution and gives control to the workstation user or to a specified program.

When all of the handles that access one end of a pipe have been closed.

One or more fields in which the result of an operation is kept.

(1) A portion of storage used to hold input or output data temporarily. (2) To allocate and schedule the use of buffers. (A)

A mechanism used to request or initiate an action. See also barrel buttons, bezel buttons, mouse button, push button, and radio button.

Pipes that handle data as byte streams. All unnamed pipes are byte pipes. Named pipes can be byte pipes or message pipes. See byte stream.

Data that consists of an unbroken stream of bytes.