Re: Sockets Example Sought

["Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de>]

On Mon, 26 Nov 2012 21:37:43 -0600, Robert Love wrote:

> BTW, is there an official way to tell when the client closes the 
> socket?

None of the transport's business, which TCP/IP is.

> When  I'm reading data, I can tell.   If I'm not reading data, 
> I can call the Get_Peer(socket) function and catch an exception.  It 
> just seems there should be another way?

Normally there are multiple further layers mounted on the TCP/IP transport
stream, up to the application level. These are usually stateful, and they
may have states corresponding to a desire to disconnect, on either side
depending on the roles the sides play. [Provided, that the protocol is
connection-oriented. There are protocols which are not connection-oriented,
even though using TCP/IP as the transport. For them whether the other side
is gone might be just irrelevant.]

Of course ether side must be prepared to anticipate protocol errors and
connection loss is just one of them. Connection-oriented protocols usually
have corresponding states for this, In such a state the participants would
roll back, one of them would try to restore connection etc.

The bottom line is, usually you would not care actively checking it. Once
you experience an error you react correspondingly. [Keep-alive issues is
another story.]

-- 
Regards,
Dmitry A. Kazakov
http://www.dmitry-kazakov.de