Re: How to service multiple socket clients

[boldt@xxxxxxxxxx]

Buck wrote:
>I'm working with sockets and have a mental block.
>...
>  Is it time to abandon the idea of
>multiple clients here and go with a simple "listener/talker" that sends
>requests to a spawned client server?  Do all the "long" work
asynchronously
>and have the socket program handle communications chores only?  How do I
>handle atomic operations like a login sequence that need to run in order?
>
>Ow, my head hurts.

You might find it easier to program what you want in C.  Normally,
for such TCP server apps, when a client connects to the server,
the client spawns off a thread to process the requests from that
one client.  In the meantime, the server thread loops around to
wait for new clients.  (There are plenty of examples of TCP server
coding in C on the internet.  Just use your favorite search tool.)

RPG has poor support for threads, and so C is the better choice.
Your C program could still call RPG procedures in modules defined
with the THREAD(*SERIALIZE) options.  But that option serializes
calls to the module, and client threads may still block waiting
for the module to be available.

Another option is to service requests using the HTTP server.
You'll still have to manage state information yourself somehow,
but all the multi-threading details can be handled by the HTTP
server.

Cheers!  Hans

Hans Boldt, ILE RPG Development, IBM Toronto Lab, boldt@ca.ibm.com