We have implemented a system where our client applications dials in to a server application using RAS. We then use WinSock to establish bi-directional communications between server and client. If the line goes down the client is alerted by RAS but the server dos'nt know that the connection is down. He merrily pumps messages into the socket thinking all is well. We dont find any events or methods on the WinSock control which tells us that the connection has broken. We dont want to implement periodic status messages flowing in either direction so the recipient can know when the line is down.
How else can we determine at the SERVER that the connection is no longer valid?