OSF DCE Application Development Guide--Core Components

Basic RPC Routine Usage
server binding handles that refer to server binding information obtained from either
source.
13.3.1 Searching a Namespace
To obtain binding information from a namespace, a client can do one of the following:
• The client must call the import routines rpc_ns_binding_import_begin(), rpc_ns_-
binding_import_next( ), and rpc_ns_binding_import_done( ) to obtain a binding
handle for a compatible server.
• The client must call the lookup routines rpc_ns_binding_lookup_begin(), rpc_ns_-
binding_lookup_next( ), and rpc_ns_binding_lookup_done( ) to obtain a list of
binding handles for a compatible server. Select a binding handle from the list by
calling either of the following:
— The NSI select routine rpc_ns_binding_select(), which selects a binding handle
at random
— A user-defined select routine, which implements an application-specific selection
algorithm
• The client must use the automatic method of binding management to make the client
stub transparently manage binding information.
In this case, the application code lacks any calls to the NSI interface. However, the
automatic method does require the client to identify the directory service entry at
which to begin the search for binding information. The client must specify the
starting entry name as the value of the NSI-defined RPC_DEFAULT_ENTRY
environment variable.
An NSI import or lookup operation searches server entries for a compatible server. On
finding such a server entry, the search operation copies the server binding information
associated with the requested interface and an object UUID. The search operation then
creates a randomly ordered list of server binding handles to refer to the potential
bindings represented by the binding information.
Figure 13-3 illustrates the use of a server binding handle to refer to server binding
information selected by an import operation.
Figure 13-3. Importing Server Binding Information
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