OSF DCE Application Development Guide--Core Components

Developing a Simple RPC Application

In this example, after each call to an RPC runtime routine, the client program calls the

application-speciﬁc ERROR_CHECK macro. If the status from the RPC runtime

routine is not error_status_ok, dce_error_inq_text( ) is called and the error message is

printed.

As speciﬁed in the greet.idl interface deﬁnition, the greet application uses explicit

handles. The client therefore passes a binding handle of type handle_t as the ﬁrst

parameter of the greet procedure. At runtime, when the client makes its ﬁrst remote

procedure call, the handle is only partially bound because the client does not know the

particular endpoint on which the server is listening; for delivery of its requests to the

server endpoint, the client depends on the endpoint mapping service of the dced process

on the server host.

11.5 Writing the Server Code

The following subsections describe the server program for the greet application. The

greet_server program takes one argument and is invoked as follows:

greet_server CDS_pathname

The greet_server program uses the input argument to establish an entry for itself in the

DCE CDS namespace.

The greet server program has two user-written modules:

• The greet_server.c module contains the server main function and performs the

initialization and registration required to export the greet interface.

• The greet_manager.c module contains the code that actually implements the greet

operation.

11.5.1 The greet_server.c Source Code

Most applications should use the DCE convenience routines for server initialization

routines (routines that begin with dce_server_) to prepare servers to listen for remote

procedure calls. These routines are simple to use, prepare a server so that dced can

manage it, and they allow enough ﬂexibility to do most typical initializations. However,

for detailed control, applications can also use the lower-level RPC API to do server

initialization. In this chapter, we describe how to use the RPC API for server

initialization.

In this section, the greet_server.c module is described and shown in successive pieces.

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