setsockopt, SO_REUSEADDR question

[Stephen J. Turner]

Constantinos A. Kotsokalis wrote:
> 
> Hello people,
>   pardon me if this has been answered before, couldn't find any trails.
>   I have the following code:
> 
> addr = '127.0.0.1', 5050
> srv = SocketServer.ThreadingTCPServer(addr, handle_con)
> srv.socket.setsockopt(SOL_SOCKET, SO_REUSEADDR, 1)
> srv.serve_forever()
> 
>   Everything is working as expected, except for the fact that the
>   setsockopt does not do what i'd like it to. I understand it's
>   highly possible I've passed wrong arguments but could not find
>   any help on the right ones. What I want it to do is to be able to
>   start a server on port 5050, even if another server was just shut
>   down and there's still a closing listen socket there. Since it does
>   not work, I have to wait about 30 sec between each run of my
>   program.
>   Any advice, please?
> 
>     Thank you,
>           Costas

The problem is that the SO_REUSEADDR socket option must be set before
the address is bound to the socket.  This can be done by subclassing
ThreadingTCPServer and overriding the server_bind method as follows:

import SocketServer, socket
class MyThreadingTCPServer(SocketServer.ThreadingTCPServer):
    def server_bind(self):
	self.socket.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
	self.socket.bind(self.server_address)

Regards,
Stephen

-- 
Stephen J. Turner <sjturner at ix.netcom.com>