The simple fact of the matter is that socket.makefile() has never worked for non-blocking sockets on 2.x. I doubt Twisted would be so broken as to use it in that context, but if that's the case, you should report a bug to them. If it's your own code, just use the socket directly (and call recv() and friends).

3.x should work fine, in that read() will return a short read (or None if nothing could be read before EAGAIN). Still, more complex calls such as readline() may still give incorrect results.