OSF DCE Application Development Guide--Core Components

OSF DCE Application Development Guide—Core Components

3. The address from which the client is making the remote procedure call, which the

communications protocols supply to the server

A server application can use the client binding handle to ask the RPC runtime about the

object UUID requested by a client or about the client’s authentication information.

12.4 Endpoints

An endpoint is the address of a speciﬁc server instance on a host system. Two kinds of

endpoints exist: well-known endpoints and dynamic endpoints.

12.4.1 Well-Known Endpoints

A well-known endpoint is a preassigned stable address that a server uses every time it

runs. Well-known endpoints typically are assigned by a central authority responsible for

a transport protocol; for example, the Internet Assigned Numbers Authority assigns

endpoint values for the IP family of protocols. If you use well-known endpoints for a

server, you should register them with the appropriate authority.

Well-known endpoints can be declared for an interface (in the interface declaration) or

for a server instance, as follows:

• Any interface deﬁnition can be associated with one or more endpoints, along with the

RPC protocol sequence corresponding to each endpoint (the endpoint attribute).

When compiling an interface, the IDL compiler stores each combination of endpoint

and protocol sequence in the interface speciﬁcation. If a call is made using binding

information that lacks an endpoint, the RPC runtime automatically looks in the

interface speciﬁcation for a well-known endpoint speciﬁed for the protocol sequence

obtained from the binding information. If the interface speciﬁcation contains an

appropriate endpoint, the runtime adds it to the binding information.

• Alternatively, server-speciﬁc, well-known endpoints can be deﬁned in server

application code. When asking the runtime to use a given protocol sequence, the

server supplies the corresponding endpoints to the RPC runtime. On a given system,

each endpoint can be used by only one server at a time. If server application code

contains a hardcoded endpoint or the server’s installers always specify the same

well-known endpoint, only one instance of the server can run per system.

When a server exports its binding information to a namespace server entry, the export

operation includes any well-known endpoints within the server binding information

stored in the server entry.

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