OSF DCE Application Development Guide--Core Components

OSF DCE Application Development Guide—Core Components

interface identiﬁer, object UUID, and binding information that the server offers, the

endpoint mapper service creates an element in the local endpoint map.

A server does not necessarily need to register well-known endpoints; however, by

registering well-known endpoints, the server ensures that clients can always obtain them.

Registration also makes the endpoints accessible to administrators, who can use the DCE

control program, dcecp, to show the map elements of an endpoint map by using the

endpoint show operation.

Servers can remove map elements from a local endpoint map by using the

rpc_ep_unregister( ) routine. Servers should unregister endpoints after they stop

listening.

13.2.6 Making Binding Information Accessible to Clients

A server needs to make its binding information accessible to clients. Usually, a server

uses the NSI export operation to place its binding information into a server entry.

However, it is also possible for servers to make string bindings accessible to clients. In

any case, the server obtains its binding information from the runtime by ﬁrst using the

rpc_server_inq_bindings( ) routine to ask for a list of binding handles.

13.2.6.1 Using String Bindings to Provide Binding Information

While implementing and debugging a server program you may temporarily want to

communicate binding information to clients by using string bindings. This allows a

server to establish a client/server relationship without registering endpoints in the local

endpoint map or exporting binding information to a namespace.

The server can convert into a string each binding handle in the list obtained from the

rpc_server_inq_bindings( ) call by calling rpc_binding_to_string_binding( ). The

resulting string binding is always fully bound. The server then makes some or all of its

string bindings available to clients somehow; for example, by placing the string bindings

in a ﬁle to be read by clients or users or both.

13.2.6.2 Exporting Binding Information

Servers can export binding information (and interface identiﬁers) or objects or both by

calling the rpc_ns_binding_export( ) routine. To export binding information associated

with a given RPC interface, a server uses an interface handle. The interface handle is

created by the IDL compiler as a reference to information about the interface that the

compiler stores in an interface speciﬁcation.

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