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Flexible, Portable, and Extensible Administration

The DCE control program is built on a portable command language called Tcl (pronounced "tickle"), which stands for Tool Command Language developed by John K. Osterhout at the University of California at Berkeley, California. Most computers provide a command language of some sort to give users a flexible and extensible way to access and use system capabilities. For instance, many UNIX-style systems offer shell language interpreters and Digital Equipment Corporation's OpenVMS operating system offers the Digital Command Language (DCL). But these command languages are not always portable. Commands and scripts based on one command language might not work in other command language environments.

Tcl, on the other hand, is a platform-independent command language that runs on every system where DCE is installed. A Tcl command interpreter and the DCE Control Program which uses it are provided as part of the DCE software.

The availability of both the DCE control program and the DCE control program language offer important benefits to DCE administrators:

· You can perform virtually all routine DCE operations from within a single administrative interface.

· Most DCE administrative operations are consistently and uniformly executed from any platform allowing administrators to manage just about all DCE operations from any DCE system in the cell. Non-UNIX DCE platforms might not handle all DCE control program file operations.

· The dcecp program provides administration objects with names like clearinghouse, principal, and endpoint. This direct approach makes DCE administration intuitive and consistent. While for now, this has only the appearance of being object oriented it's an important step toward a true object-oriented administration interface.

· Task objects (high-level dcecp scripts that perform complex DCE operations) reduce the training requirements for DCE administrators. One need not be a DCE guru to perform routine DCE administrative tasks.

· You can adapt the supplied task objects to new uses or write new task objects or scripts using the dcecp operations along with more general commands provided within Tcl.

· The dcecp language allows the use of variables, if statements, looping functions and other programming operations that let you boost the power of your operations. For instance, looping functions let you repeat operations on multiple objects such as users, servers, or CDS entries.

· Administrators can easily share their tools because scripts can be moved to foreign platforms without change. For instance, enterprises with multiple cells could use dcecp scripts to propagate a common cell configuration throughout the enterprise.

The DCE control program is an administrative interface that you can use to manage most aspects of the DCE core components. You cannot use dcecp to manage every aspect of DCE. First, not all of the existing programs are replaced by dcecp. For instance dcecp cannot control GDS or DFS.

The topics in Part 1 discuss how you can use the dcecp program to administer the core services in your DCE environment. We also discuss how to make your operations do more by using Tcl constructs on the command line and by writing your own customized operations as scripts. We do not provide a complete discussion of Tcl or its companion toolkit (called Tk) for the X11 window system. For in-depth discussions of these topics, refer to Tcl and the Tk Toolkit, John K. Osterhout, © 1994, Addison Wesley Publishing Company.