cache -

A high-speed buffer storage that contains frequently accessed instructions and data; it is used to reduce access time.

A presentation space from a Presentation-Manager-owned store of micro presentation spaces. It can be used for drawing to a window only, and must be returned to the store when the task is complete.

Computer-Aided Design.

(1) The action of bringing a computer program, a routine, or a subroutine into effect, usually by specifying the entry conditions and jumping to an entry point. (I) (A) (2) To transfer control to a procedure, program, routine, or subroutine.

A sequence of instructions together with any associated data necessary to execute a call. (T)

An action that removes the current window or menu without processing it, and returns the previous window.

In the OS/2 operating system, a menu that appears when the arrow to the right of a cascading choice is selected. It contains a set of choices that are related to the cascading choice. Cascaded menus are used to reduce the length of a menu. See also cascading choice.

In SAA Common User Access architecture, a choice in a menu that, when selected, produces a cascaded menu containing other choices. An arrow () appears to the right of the cascading choice.

In PM programming, provides the body of a window procedure. There is usually one CASE statement for each message type supported by an application.

Color graphics adapter.

A list in which the data elements may be dispersed but in which each data element contains information for locating the next. (T) Synonymous with linked list.

A letter, digit, or other symbol.

In computer graphics, the boundary that defines, in world coordinates, the horizontal and vertical space occupied by a single character from a character set. See also character mode. Contrast with character cell.

The physical, rectangular space in which any single character is displayed on a screen or printer device. Position is addressed by row and column coordinates. Contrast with character box.

The means of addressing a character in a character set, sometimes called code point.

A device that performs I/O operations on one character at a time. Because character devices view data as a stream of bytes, character-device data cannot be randomly accessed. Character devices include the keyboard, mouse, and printer, and are referred to by name.

A mode that, in conjunction with the font type, determines the extent to which graphics characters are affected by the character box, shear, and angle attributes.

(1) An ordered set of unique representations called characters; for example, the 26 letters of English alphabet, Boolean 0 and 1, the set of symbols in the Morse code, and the 128 ASCII characters. (A) (2) All the valid characters for a programming language or for a computer system. (3) A group of characters used for a specific reason; for example, the set of characters a printer can print.

In SAA Advanced Common User Access architecture, a square box with associated text that represents a choice. When a user selects a choice, an X appears in the check box to indicate that the choice is in effect. The user can clear the check box by selecting the choice again. Contrast with radio button.

(1) (D of C) In SAA Advanced Common User Access architecture, a symbol that shows that a choice is currently in effect. (2) The symbol that is used to indicate a selected item on a pull-down menu.

In the OS/2 operating system, a process started by another process, which is called the parent process. Contrast with parent process.

A window that appears within the border of its parent window (either a primary window or another child window). When the parent window is resized, moved, or destroyed, the child window also is resized, moved, or destroyed; however, the child window can be moved or resized independently from the parent window, within the boundaries of the parent window. Contrast with parent window.

(1) An option that can be selected. The choice can be presented as text, as a symbol (number or letter), or as an icon (a pictorial symbol). (2) (D of C) In SAA Common User Access architecture, an item that a user can select.

(1) To press more than one button on a pointing device while the pointer is within the limits that the user has specified for the operating environment. (2) (D of C) In graphics, a short line segment whose end points lie on a circle. Chords are a means for producing a circular image from straight lines. The higher the number of chords per circle, the smoother the circular image.

A way of categorizing objects based on their behavior and shape. A class is, in effect, a definition of a generic object. In SOM, a class is a special kind of object that can manufacture other objects that all have a common shape and exhibit similar behavior (more precisely, all of the objects manufactured by a class have the same memory layout and share a common set of methods). New classes can be defined in terms of existing classes through a technique known as inheritance.

A class method of class <X> is a method provided by the metaclass of class <X>. Class methods are executed without requiring any instances of class <X> to exist, and are frequently used to create instances. In System Object Model, an action that can be performed on a class object.

In System Object Model, the run-time implementation of a class.

The set of properties that apply to every window in a window class.

(1) A functional unit that receives shared services from a server. (T) (2) A user, as in a client process that uses a named pipe or queue that is created and owned by a server process.

The part of the window, inside the border, that is below the menu bar. It is the user's work space, where a user types information and selects choices from selection fields. In primary windows, it is where an application programmer presents the objects that a user works on.

An application that creates and manipulates instances of classes.

The window in which the application displays output and receives input. This window is located inside the frame window, under the window title bar and any menu bar, and within any scroll bars.

The area of the paper that can be reached by a printer or plotter.

In SAA Common User Access architecture, an area of computer memory, or storage, that temporarily holds data. Data in the clipboard is available to other applications.

In computer graphics, removing those parts of a display image that lie outside a given boundary. (I) (A)

The area in which the window can paint.

A clipping boundary in world-coordinate space.

The minimum unit of time that the system tracks. If the system timer currently counts at a rate of X Hz, the system tracks the time every 1/X of a second. Also known as time tick.

Character-device name reserved for the system clock.

An assignment of graphic characters and control-function meanings to all code points.

(1) Synonym for character code. (2) (D of C) A 1-byte code representing one of 256 potential characters.

An executable section of programming code within a load module.

See dithering.

An adapter that simultaneously provides four colors and is supported by all IBM Personal Computer and Personal System/2 models.

The name and parameters associated with an action that a program can perform.

An area composed of a command field prompt and a command entry field.

An entry field in which users type commands.

On a display screen, a display line, sometimes at the bottom of the screen, in which only commands can be entered.

A state of a system or device in which the user can enter commands.

A field prompt showing the location of the command entry field in a panel.

Definitions of those application development languages and services that have, or are intended to have, implementations on and a high degree of commonality across the SAA environments. One of the three SAA architectural areas. See also Common User Access architecture.

Guidelines for the dialog between a human and a workstation or terminal. One of the three SAA architectural areas. See also Common Programming Interface.

To translate a program written in a higher-level programming language into a machine language program.

A window composed of other windows (such as a frame window, frame-control windows, and a client window) that are kept together as a unit and that interact with each other.

The use of a computer to design or change a product, tool, or machine, such as using a computer for drafting or illustrating.

Character-device names reserved for serial ports 1 through 3.

Character-device name reserved for the console keyboard and screen.

A pull-down menu associated with a menu item that has a cascade mini-push button beside it in an object's pop-up menu. The conditional cascaded menu is displayed when the user selects the mini-push button.

In SAA Common User Access architecture, an object that holds other objects. A folder is an example of a container object. See also folder and object.

In SAA Common User Access Architecture, help that gives specific information about the item the cursor is on. The help is contextual because it provides information about a specific item as it is currently being used. Contrast with extended help.

Touching or joining at a common edge or boundary, for example, an unbroken consecutive series of storage locations.

In SAA Advanced Common User Access architecture, a component of the user interface that allows a user to select choices or type information; for example, a check box, an entry field, a radio button.

A storage area used by a computer program to hold control information. (I) (A)

In the Presentation Manager, a program used to set up user preferences that act globally across the system.

(1) The basic functions of the operating system, including DOS emulation and the support for keyboard, mouse, and video input/output. (2) A computer program designed to schedule and to supervise the execution of programs of a computer system. (I) (A)

A window that is used as part of a composite window to perform simple input and output tasks. Radio buttons and check boxes are examples.

An instruction within a document that identifies its parts or indicates how to format the document.

A two-dimensional set of points used to generate output on a video display of printer.

A choice that places onto the clipboard, a copy of what the user has selected. See also Cut and Paste.

The action of determining which element or object within a picture is at a given position on the display. This follows a pick operation.

A window in which the application's help information is displayed.

Common Programming Interface.

An extended attribute that is necessary for the correct operation of the system or a particular application.

(1) In programming languages, a part of an asynchronous procedure that cannot be executed simultaneously with a certain part of another asynchronous procedure. (I)

Note: Part of the other asynchronous procedure also is a critical section. (2) A section of code that is not reentrant; that is, code that can be executed by only one thread at a time.

Common User Access architecture.

In computer graphics, the position, in user coordinates, that becomes the starting point for the next graphics routine, if that routine does not explicitly specify a starting point.

A symbol displayed on the screen and associated with an input device. The cursor indicates where input from the device will be placed. Types of cursors include text cursors, graphics cursors, and selection cursors. Contrast with pointer and input focus.

In SAA Common User Access architecture, a choice that removes a selected object, or a part of an object, to the clipboard, usually compressing the space it occupied in a window. See also Copy and Paste.