|SocketIOTask| is a task-class template that holds a reference to
a Socket I/O object. It replaces |UnixSocketImplTask|, which only
supports objects of type |UnixSocketImpl|.
|SocketIOBase| is a base class for Socket I/O classes. It's not a
requirement, but provides a number of helpful methods for common
I/O operations on the I/O thread.
|SocketIODeleteInstanceRunnable| deletes a Socket I/O object on the
main thread. This is required to serialize the close operation of
Socket consumers.
|SocketIORunnable| is a runnable class template that holds a
reference to a arbitrary Socket I/O object. |SocketIORunnable|
replaces |UnixSocketImplRunnable|, which only handles objects of
type |UnixSocketImpl|.
|SocketConsumerBase| handles connection state for |UnixSocketConsumer|
and its derived classes. Implementing classes must override a number of
virtual methods, to handle notifications about changes to the state of
the connection.
