We have a legacy protocol that we call RS232 transfer because it originally ran on RS232 com ports. It is still used by custom programming for some inter-company transaction sharing. For example, between Esbenshade Farms and Hershey Ag.
RS232 transfer works on type 11 UDP ports. The standard configuration runs the server on port 19. Timeshare user 0 handles server functions on cram device 4. Any timeshare user can do client functions on cram device 3. There is a single global buffer at ‘netbuffr’ for client functions, and a single global buffer at ‘servbuf’ for server functions.
Note that while one side is considered the server and the other side the client from the perspective of this protocol, both sides are running on an ABC server.