OSF DCE Application Development Guide--Introduction and Style Guide

Chapter 5. Using the DCE Name Service
Correct use of the DCE RPC Name Service Interface (NSI) is essential to the operation
of a distributed application, since NSI is the medium through which the application’s
distributed parts must find each other. NSI works with named database entries which are
hierarchically organized into subdirectories and referenced by the familiar pathname
convention.
5.1 Introduction to Using NSI
It is important to remember that names and objects are separate things in DCE.
Consider, for example, these two DCE names:
/.../tinseltown.org/dce/printers/macmillan
/.../tinseltown.org/dce/employees/goethe
These strings are not filenames or file directory names; if you attempt to execute the ls
command on them, you will only get an error message. They are pathnames that identify
entries in the DCE Directory Service, which is DCE’s database for storing distributed
information. This database is often informally referred to as the namespace.
The most important type of distributed information stored in the namespace is
information that enables RPC clients to rendezvous with RPC servers; it is called binding
information. The directory service can be used to hold other kinds of data too, but the
main subject of the following discussions will be its use as a binding repository.
The set of binding name entries is like a huge data structure of pointers from object
names to object locations, and the directory service is used mostly as a public DCE
locational database, enabling servers to advertise themselves and the objects and
resources that they manage, and clients in turn to find and access them. You should
never confuse objects with their names; the two are separate things. In particular, the
directory service data associated with a name is held in one place (namely, the directory
server’s database), while the data associated with the object named is held in other place
(namely, the object server’s database).
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