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Motif 2.1 Programmer's Guide
Appendix C. Glossary
accelerator
A key or sequence of keys (typically a modifier key and some other key)
that provides a shortcut, immediately accessing a program function.
* See also shortcut key.
action
In awk, lex, and yacc, a C language program fragment that defines what the
program does when it recognizes input.
A procedure associated with a widget and invoked by the Xt event
dispatcher when the widget receives an event of a given type. The
widget's translation table associates event descriptions with actions.
A field in an EVS Event Controller that tells EVS to transmit, discard, or
log the notification.
An operation requested by activating an element.
activation
Invocation of a component's primary action. For example, the user
activates a PushButton by pressing BSelect on the PushButton.
The process of initiating the activity associated with a choice.
anchorA position in a collection of selectable objects that marks one endpoint of
an extended selection range.
atomAn identifier that is unique to the display and is associated with a given
name. Common uses are to identify properties, types, and selections.
bitmapA pixmap with a depth of one bit.
callback
DFS: A procedure that is registered with a token to be called
automatically if the token is revoked. The act of revoking a token is also
referred to as a callback.
An application-defined procedure that a widget invokes at some specified
time. Often the widget invokes a callback from an action routine when the
widget receives an event of a given type. Widgets that invoke callbacks have
resources whose value is a list of callback procedures.
character set
A group of characters used for a specific reason; for example, the set of
characters a printer can print or a keyboard can support.
A set of characters that, either individually or in combination,
represents meaningful words in a language.
class
A category into which objects are placed on the basis of both their
purpose and their internal structure. See also object class, OM
class.
A group of elements all of the same type. A resource class represents a
group of resources with different names. A widget class represents the
procedures and data structures shared by all widgets of that class.
In object-oriented programming, specifies the name, structure, and
components of objects. See also object, object-oriented
programming, subclass.
Pertains to the I/O characteristics of a device. Devices are classified as
2block2 or 2character2.2 2
client
CDS: Any application that interacts with a CDS server through the
CDS clerk.
DTS: Any application that interacts with a DTS server through the
DTS clerk.
RPC: The party that initiates a remote procedure call. Some
applications act as both an RPC client and an RPC server. See also
server.
DFS: A consumer of resources or services. See also
server.
GDS: The client consists of an application that links the DUA
library, the C-stub that handles the connection over the communications
network for accessing a remote server, and the DUA cache.
A program written specifically for use with the X Window System. Clients
create their own windows and know how to resize themselves.
The portion of a distributed program that issues requests for service to a
server. The client's address space is separate from the server's
address space; the two programs may reside on separate machines. See
also server.
clippingThe restriction of output to a particular area of the screen by a given
boundary. For example, windows are clipped by their parents.
code set
A collection of characters with assigned code values. For example, ASCII
contains a specified group of characters; each character has an assigned value
in the set.
The set of binary values needed to represent all the characters in a
language.
colormapAn association between pixel values and colors. Each color is represented
by a triple of red, green, and blue values that result in a particular color
on a particular screen. Each window has an associated colormap that determines
what color is used to display each pixel.
compositeOne of a group of widgets that can have child widgets and can manage their
children's geometry.
cursor
A movable symbol (such as an underline) on a display that indicates to the
user where the next typed character will be placed or where the next action
will be directed.
A marker that indicates the current data access location within a file.
A graphical image, usually a pipe () or block, that shows the location
where text will appear on the screen when keys on the keyboard are pressed or
where a selection can be made.
A visible cue that indicates where the user's interaction with the
keyboard will be performed.
destinationThe location at which transfer actions place data.
dialog
A widget that provides a means of communicating between the user and the
application. A dialog is a popup that usually asks a question or presents some
information to the user. A dialog can be modal, suspending the application
until the user provides a response, or modeless, allowing the user to interact
with the application during the dialog.
In an interactive system, a series of related inquiries and responses
similar to a conversation between two people.
A specialized interaction with the user that occurs in a secondary window.
displayAn abstraction that represents the input and output devices controlled by a
single server. Usually a display consists of a keyboard, a pointing device,
and one or more screens.
drag and drop
A transfer mechanism where data is dragged from a source to a drop site
using mouse motion.
A user interaction in which a user drags source elements to a target
element on which they are dropped.
drag iconA graphic that is generated using pixmaps and is moved during a drag
operation. The drag icon is composed of a source pixmap, a state cursor, and
an operation cursor.
drag initiatorThe client within whose window the user starts a drag transaction. See
also drag source.
drag sourceThe object whose graphical representation is being dragged and whose data
the user wishes to transfer.
drawableAn entity that can be the source or destination for a graphics operation.
Both windows and pixmaps are drawables.
drop siteAn area of the screen on which the user can drop a drag icon.
event
The enqueueing or dequeueing of an element.
An occurrence of significance to a task.
Information generated either asynchronously from a device or as the
side-effect of a client request. Events are grouped into types and are not
sent to a client by the server unless the client has issued a specific request
for information of that type. Events are usually reported relative to a
window.
A synchronization primitive for asynchronous notification of a change of
state.
An occurrence, or happening, that is significant to an application. Events
are typically asynchronous, in that they do not happen as a result of an
action taken by the user. Also, the information returned to the user for an
event.
In XTI, events are asynchronous and the transport user acts on the
occurrences.
A means by which the server notifies clients of changes of state. An event
may be a side effect of a client request, or it may have a completely
asynchronous cause, such as the user's pressing a key or moving the
pointer. In addition, a client may send an event, via the server, to another
client.
In EVS, an occurence or condition that is significant to an application.
event handlerA procedure called by the Xt event dispatcher when a widget receives an
event of a given type. Event handlers provide input processing at a lower
level than callbacks or action routines.
event loopA program loop in which the application receives an event, handles the
event, and then waits for the next event. An event loop usually does not end
until the user terminates the application. Xt provides an event-dispatching
loop suitable for most applications.
export targetA type of object that a drag source can process.
expose methodA method that regenerates the content of a window.
focus
A state of the system that indicates which component receives keyboard
events. A component is said to have the focus if keyboard events are sent to
that component.
* See also keyboard focus.
The place to which keyboard input is directed.
fontA collection of glyphs and associated metrics usually used to display text.
gadgetAn object that is like a primitive widget in most respects except that it
has no associated window or translations. A gadget depends on a manager parent
for its colors and for input dispatching.
GCSee graphics context.
geometryThe elements of a widget's layout, including its size, location, and
stacking order.
geometry managementThe process by which the user, parent widgets, and child widgets negotiate
the actual sizes and locations of the widgets in an application. In general, a
child widget can ask its parent to change its geometry but cannot make any
changes on its own. A parent can grant or reject a request from its child and
can force changes on the child at other times.
grabA client's assertion of exclusive use of a keyboard key, the keyboard,
a pointer button, the pointer, or the server. Applications usually do not use
explicit grabs, but toolkits and window managers often use them to implement
such features as menus and accelerators.
graphics context (GC)A collection of attributes that determine how any given graphics operation
affects a drawable. Each graphics operation on a drawable is executed using a
given graphics context specified by the client. Some attributes of a graphics
context are the foreground pixel, background pixel, line width, and clipping
region.
hotspot
The location in a cursor that corresponds to the coordinates of the
pointer position.
The area of a graphical image used as a pointer or cursor that is defined
as the point of the pointer or cursor.
I18NSee internationalization.
import targetA type of object that a drop site can process.
input contextThe mechanism used to provide the state information flow between an
application and the input method.
input focus
* See also keyboard focus.
* See also focus.
input methodA layer of mapping between the keyboard keys (or combination of keys) that
the user types and the text data that is passed to the application.
insertion cursor
The graphical symbol that provides the visual cue to the location of the
insertion point.
The graphical symbol that provides the visual cue to the location of the
insertion point in a Text component.
internationalization (I18N)The process of generalizing programs or systems so that they can handle a
variety of languages, character sets, and national customs.
keyboard focus
Indicates the window or component within a window that receives keyboard
input. It is sometimes called the input focus.
A state of the system that indicates which component receives keyboard
events. A component is said to have the focus if keyboard events are sent to
that component.
keyboard traversalThe set of actions, usually invoked from the keyboard, that cause focus to
move from one component to another within an application or between
applications.
localizationThe process of providing language-specific or country-specific information
and support for programs.
manageTo place the geometry of a child widget under the control of its parent. In
general widgets are eligible to appear on the screen only after they are
managed.
manager
RPC: A set of remote procedures that implement the operations of an
RPC interface and that can be dedicated to a given type of object. See
also object, RPC interface.
* See also device manager.
One of a group of widgets that can have children and can manage their
geometry. Managers provide colors and input dispatching for gadget children.
map
To cause a region of the processor's virtual address space to be
backed by a region of a file such that future references to addresses in the
mapped range refer to the data in the file.
To mark a window as eligible to be visible on the screen. A window
actually becomes visible when all of its ancestors are mapped and when it is
not obscured by an ancestor or by another window.
menu
A displayed list of items from which a user can make a selection.
A popup widget usually allowing the user to make a single selection from a
constrained set of choices. A menu is usually modal, suspending the
application until the user makes a selection or dismisses the menu. When torn
off, a menu becomes modeless, allowing the user to interact with the
application while the menu remains visible.
A control generally containing a list of choices of any type.
mnemonic
A symbol chosen to help the user remember the significance of the symbol.
The field of an assembler instruction that contains the acronym or
abbreviation for a machine instruction. Using mnemonics frees the programmer
from having to remember the machine's numeric operator codes.
A single character (frequently the initial character) of a Menu selection.
When the Menu is displayed and the user presses the key that corresponds to
that character, the Menu selection is chosen.
A character that the user can type (possibly augmented with Alt) to move
the focus elsewhere in a window or menu and/or to activate or toggle a choice
whose label contains and emphasizes that character.
modal
A DialogBox that requires a response before you can interact with other
components in an application.
A state of a dialog that requires the user to interact with the dialog
before interacting with other parts of the application or with other
applications. Three modal styles exist: primary application modal, full
application modal, and system modal. See also modeless.
A state in which the user must complete the operation of the mode before
continuing.
modeless
A DialogBox that does not limit your interaction with the rest of an
application.
A state of a dialog that does not require the user to interact with the
dialog before interacting with other parts of the application or with other
applications. See also modal.
A state that does not interfere with the user performing any other action.
off-the-spotA location for the pre-edit area in an input method. The input data is
displayed in a window within the application window but not at the point of
insertion.
on-the-spotA location for the pre-edit area in an input method. The input data is
displayed in a window at the point of insertion.
over-the-spotA location for the pre-edit area in an input method. The input data is
displayed in a window immediately above the point of insertion.
pane
On a display screen, the inner portion of a window used to present
information to the user. A window can consist of one or more panes.
A widget that is a child of a PanedWindow. The user adjusts the size of a
pane by means of a sash.
One of the separate areas in a split window or a paned box.
pending delete
A state of a Text component in which some user actions cause the current
selection to be deleted.
A mode of a selection scope in which an insertion within a selected region
replaces the selected item.
pixel
* See also picture element.
A unit of height and width for a window or pixmap. Each pixel has a number
of bits or planes equal to the depth of the window or pixmap. Thus, each pixel
has an integral value whose range depends on the depth of the drawable. The
pixel value is used as an index into a colormap to determine the color to
display for that pixel.
pixmapA two-dimensional array of pixels, all of the same depth. Like a window, a
pixmap is a drawable, an entity that can be the source or destination for a
graphics operation.
popupA widget that is outside the normal widget hierarchy. Any widget can have
popup children, and the widget does not manage these children. A popup's
window is a descendant of the root window, and the popup is not clipped by the
parent widget. A popup usually appears on the screen temporarily in behalf of
its parent. Dialogs and menus are the most common popups.
pre-edit areaAn area that displays the intermediate text characters for languages whose
characters may require more than one keystroke to complete.
pre-editingCreating characters in a particular language by using individual keystrokes
or combinations of keystrokes.
primitiveOne of a group of widgets that usually do not have children.
propertyAn entity associated with a window and consisting of a name, a type, a data
format, and data. Properties are often used for communicating between clients
and between a client and the window manager.
realizeTo create windows for a widget and its managed children.
receiverThe client containing the destination of a drag and drop transaction.
resource
A variable that controls a single aspect of the appearance or behavior of
an application or component.
An element of a database representing options or values for attributes of
an application. A resource is a triple consisting of a name, a class, and a
value. A name and class may consist of components, each identifying the name
or class of a particular level of a hierarchy. A widget can also have
resources, whose values are derived from the resource database or set directly
by the application.
root window
The window that covers the entire screen. The root window is the backdrop
of your X environment. All windows and graphic objects appear stacked on the
root window.
A window that covers the entire viewable extent of the screen and is the
ancestor of all other windows on the screen.
root-windowA pre-edit area (or window) that is a child of the root window and not a
part of the application window.
sash
A control with which the user changes the sizes of panes in a PanedWindow.
A box on a split bar through which users can directly manipulate the split
bar to change the sizes of associated panes.
screen
* See also display screen.
The physical surface of a workstation upon which information is shown to
users.
An abstraction that represents a single bitmapped output device on a
display.
The physical surface of a display device upon which information is shown
to users.
sensitiveEligible to receive input events. Xt does not dispatch most input events to
insensitive widgets.
server
RPC: The party that receives remote procedure calls. A given
application can act as both an RPC server and an RPC client. See
also client.
CDS: A node running CDS server software. A CDS server handles
name-lookup requests and maintains the contents of the clearinghouse or
clearinghouses at its node.
DTS: A system or process that synchronizes with its peers and
provides its clock value to clerks and their client applications.
DFS: A provider of resources or services. See also
client.
GDS: The server consists of a DSA, which accesses the database, and
an S-stub, which handles the connection over the communications network for
responding to remote clients and accessing remote servers.
An application program that usually runs in the background (daemon) and is
controlled by the System Program Controller.
On a network, the computer that contains the data or provides the
facilities to be accessed by other computers on the network.
A program that handles protocol, queuing, routing, and other tasks
necessary for data transfer between devices in a computer system.
The component of the X Window System that manages input and the visual
display.
The portion of a distributed program that handles requests for service
from one or more client programs. The server's address space is separate
from the client address spaces. See also client.
shell
A software interface between a user and the operating system of a
computer. Shell programs interpret commands and user interactions on devices
such as keyboards, pointing devices, and touch-sensitive screens and
communicate them to the operating system. OSF/1 provides three shells:
the Bourne, Korn, and C shell.
Software that allows a kernel program to run under different operating
system environments.
The command interpreter that provides a user interface to the operating
system and its commands. See also shell program, interface.
One of a group of widgets that envelop the top-level widgets, including
dialogs and menus, in an application. A shell usually has only one managed
child, and its window is often coincident with the managed child's
window. A shell usually handles communication with the window manager.
status area
An input method output-only window thaqt identifies the input style
(phonetic, numeric, stroke and radial, etc.) and the current status of an
input method interaction.
A specific part of a window used to display information about the state of
the current application task.
tab group
A widget or set of widgets to which the user traverses by means of the Tab
key. Within a tab group, the user traverses to non-tab-group descendants by
means of the arrow keys.
A control or group of controls to which the user can navigate by using
Tab.
translationA mapping from an event description to one or more actions. When a widget
receives an event, Xt searches the widget's translation table for a
matching event description. If it finds such a description, it invokes the
associated action or actions.
traversal
* See also navigation.
* See also keyboard traversal.
vertical writingThe writing of characters or glyphs in columns (to be read from top to
bottom) rather than in rows (to be read from left to right or from right to
left). Vertical writing is characteristic of some Asian languages.
virtual bindingAn assocation between an abstract key or pointer button, known as a virtual
key or virtual button, and a physical key or button on the display.
virtual keyAn abstract representation of a key that is independent of any physical
key. A virtual key is associated with a physical key by means of a virtual
binding.
widget
The technical term for user-interface components.
An object used to hold data and present an interface to the user. A widget
is a combination of state and procedure. Each widget is a member of a class,
which holds the procedures and data structures common to all widgets of that
class. A widget instance holds the procedures and data structures particular
to that single widget. Each widget class typically provides the general
behavior associated with a particular kind of interaction with the user.
window
In curses, the internal representation of what a portion of the display
may look like at some point in time. Windows can be any size, from the entire
display screen to a single character.
A division of a screen in which one of several programs being executing
concurrently can display information.
In data communications, the number of data packets a DTE or DCE can send
across a logical channel before waiting for authorization to send another data
packet. The window is the main mechanism of pacing, or flow control, of
packets.
In X.25 communications, the number of packets that can be outstanding
without acknowledgement.
In the context of the OSF/1 loader, a temporarily established mapping for
a (possibly) small piece of a file.
A data structure that represents all or part of the display screen.
Visually, a window is represented as a subarea of the display screen.
An area with visible boundaries that can be defined so that the user can
view interact with an application.
window manager
A program that controls the size, placement, and operation of windows on
the workspace. The window manager includes the functional window frames that
surround each window object and may include a separate Menu for the workspace.
A program that provides users with the capability to manipulate windows on
the workspace; for example, opening, resizing, moving, and closing windows.
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