c_api_demo

A client and a server progarm communicating via TIPC, but using an
adaptation layer written in C instead of working directly with socket
primitives. This simplifies usage of TIPC.

The demo shows four use cases:
1) Client sends a datagram message to server using its service address.
   The server responds with a datgram usng the client's socket address.
   Both endpoints use a SOCK_RDM socket.

2) Client sends a datagram message using an invalid service address.
   The system rejects the message back to sender with error code
   "No route to host"

3) Client sends a setup message containing data to server using a 
   service address. The server accepts the setup message and responds
   back to client with another data message.  This is an example of the
   TIPC specific two-way "implicit" connection setup protocol.
   Both endpoints use a SOCK_STREAM socket in this case, but it could
   just as well have been a SOCK_SEQPACKET.

4) Client makes a traditional TCP style connect(), resulting in a 
   TIPC internal two-way SYN/SYNACK signalling to establish the 
   connection. Thereafter we have the same message exchange as above
   across the connection.
   Both endpoints use a SOCK_SEQPACKET socket in this case, but it could
   just as well have been a SOCK_STREAM.