OSF DCE Application Development Guide--Introduction and Style Guide
OSF DCE Application Development Guide—Introduction and Style Guide
Figure 5-10. Importing from a Model That Uses Grouped Bindings
Endpoint
Mapper
Server
A
B
C
D
Server
bindings
Server
group
Server
group
Server
group
Server
group
"A"
object
UUID
"B"
object
UUID
"C"
object
UUID
"D"
object
UUID
attrib
attrib attrib attrib
Server entry
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namespace
Client
import binding information
for object "A"
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call through to server
server’s host
machine
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client’s machine
The client shown in the figure imports a binding for object A. This becomes (through the
group attribute) a referral back to the server’s entry where the bindings are held, and a
binding is indirectly imported from the server entry. The object UUID for A is read, in a
separate operation, directly from the object’s entry. With this information in its binding
handle, the client makes its first remote call through the server’s interface. The call finds
its way to the endpoint mapper via the partial binding information, and the endpoint
mapper completes the binding by looking up the object UUID, which was registered
there by the server.
5.16 Global Organization of the Namespace
Since DCE is designed to support very large namespaces, it uses a hierarchical service
for binding. The global scale is separated into cells whose boundaries are
administratively defined. For example, a company using DCE might have a cell
containing its employees and local services. The cell namespace administrator could
decide to put all the service entries in a single directory if the cell were small.
Both the import and export name service operations support default values derived from
environment variables; for example, RPC_DEFAULT_ENTRY_NAME. The
environment variables can be set by start-up files to the name of a well-known directory
within the cell. The only remaining decision then will be how to name the actual entries
within the directory. One easy method is to use mnemonic names, or names of interfaces
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