| The Relationship among X, Motif, and CDE X, OSF/Motif, and CDE are enabling framework technologies. Taken together, X, Motif, and CDE make up the three graphical layers on top of the operating system and hardware platform. The GUI layers provide increasingly richer ease-of-use functions in a progressive series of layers that buffer the end user from the "user-hostile," character-based interface of the operating system layer. The X Window System The X Window System consists of the following: Xlib - Low-level library for programming window manipulation; graphics capabilities such as line drawing and text placement; controlling display output, mouse, and keyboard input; and application network transparency. Xt Intrinsics - Higher-level library for programming widgets and gadgets (graphical controls components like menus, scrollbars, and push buttons). Display servers - Hardware-specific programs, one per display, that manage the graphical input and output. Interclient communication conventions (ICCC) - A manual specifying standards for how X client programs should communicate with each other. Configuration files - One configuration file that specifies the default session to start (sys.x11start) and another specifying values for resources used to shape the X environment (sys.Xdefaults).
Through these mechanisms, X provides the standard upon which the graphical part of the network-oriented, client/server, distributed computing paradigm is based. A knowledge of Xlib and the Xt Intrinsics is important for programming in X and for programming at the Motif level. For system administrators, however, as long as the display servers work and X client applications are ICCC-compliant, you shouldn't need to delve into the X layer. CDE enables you to view X pretty much as part of "all that underlying technological infrastructure stuff" and focus on developing appropriate configurations of CDE to meet your users' work contexts. Motif Motif consists of the following: mwm window manager - Executable program that provides Motif-based window frames, window management, and a workspace menu in the X environment. Motif widget toolkit - Higher-level library of widgets and gadgets, the graphical components used to control the user environment. Motif style guide - A manual defining the Motif appearance and behavior for programmers. Configuration files - The system.mwmrc file containing configuration information for the workspace menu and key and button bindings. Resources for the window manager are in mwm in the /usr/lib/X11/app-defaults directory.
Motif provides the window manager for the end-user, the widget toolkit for application developers, and the style guide to help developers design and build proper Motif-conformant applications. As with X, system administrators can view Motif mostly as "programmer's stuff," part of the underlying infrastructure, and focus on developing appropriate CDE configuration files. CDE As we have already seen, CDE consists of the following: Workspace Manager - Executable program that provides Motif-based window frames, window management, a workspace menu, and the front panel. File Manager - Program that iconically manages files and directories through direct manipulation. Style Manager - Container of dialog boxes that control elements of the CDE environment, like workspace color and fonts. Help Manager - This program provides context-sensitive help text on CDE components. Login Manager - Daemon-like application that handles login and password verification. Session Manager - Manager that handles saving and restoring user sessions. Application Manager - Manager that registers and keeps track of applications in the CDE environment. Configuration Files - A big bunch, most of which you can avoid dealing with (see the next section).
CDE also provides a number of basic, end-user productivity-enhancing applications. In general, CDE provides a graphical environment into which users, or you, their system administrator, can incorporate the software tools needed to do their work. |