Giovanni P. Deretta wrote:
The problem is that a socket is *conceptually* not copyable. Even if you have multiple handles to it, they all refer to the same underlying stream. Standard streams are not copyable for the same reason. If you want different objects to *share* a socket you use a shared_ptr and dynamically allocate it.
In principle, it is true that a stream or a socket a conceptually not copyable. In practice, a stream or a socket is much easier to use (correctly) if it is copyable with reference semantics (and thread safe too, but that's a different story :-) ) - as ordinary C FILE*s and sockets are (although they have to be closed manually, of course.) I'm not really arguing that an asio socket has to be copyable and refcounted... yet, because I don't have the experience to determine how often I'd need to allocate it on the heap in real code. But the tutorial does allocate its sockets on the heap. :-)