Distributed Systems Development - Autonomics Development: A Domain-Specific Aspect Language Approach - page 19

IDL Input

getdate.x

rpcgen

Generated
Code

getdate_clnt.c getdate.h getdate_svc.c

User
supplied

User
supplied

compiler

client.c

server.c

RPC runtime
library

client server

Figure 2.3. Sun ONC RPC generator.

The unique program number for our implementation is 22855. The rpcgen pro-
gram is then run against the IDL file, which generates a header file getdate.h ,and
two skeleton files, getdate_clnt.c and getdate_svc.c for the client and server
implementations respectively as illustrated in Figure 2.3.
The generated files contain the marshalling and unmarshalling, binding, data
representation (XDR), and framework integration code required to implement the
ONC protocol.

2.3.6.2 ONC Example Implementation

The files generated by the rpcgen application are required to be linked with user-
supplied files for the client and server implementation. For our example, the

relevant portion of our client implementation is as follows:

if ((cl = clnt_create(server, GETDATE_PROG,
GETDATE_VERS, "udp" )) == NULL) {
clnt_pcreateerror(server);
exit(1);

}