Duplex of BSD sockets

As the title states, what are the duplex of the 开发者_运维知识库BSD sockets, full? - and that is on the same single socket.

If you read the socket(2) manual page, you will see that SOCK_STREAM type sockets are full-duplex. Same for Windows, see http://msdn.microsoft.com/en-us/library/ms740506(v=vs.85).aspx .