Python [Errno 98] Address already in use

Question

In my Python socket program, I sometimes need to interrupt it with Ctrl-C. When I do this, it does close the connection using socket.close().

However, when I try to reopen it I have to wait what seems like a minute before I can connect again. How does one correctly close a socket? Or is this intended?

Answer 1

Yes, it is intended. Here you can read detailed explanation. It is possible to override this behavior by setting SO_REUSEADDR option on a socket. For example:

sock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)

Answer 2

$ ps -fA | grep python
501 81211 12368   0  10:11PM ttys000    0:03.12  
python -m SimpleHTTPServer

$ kill 81211

Answer 3

If you use a TCPServer, UDPServer or their subclasses in the SocketServer module, you can set this class variable (before instanciating a server):

SocketServer.TCPServer.allow_reuse_address = True

(via SocketServer.ThreadingTCPServer - Cannot bind to address after program restart )

This causes the init (constructor) to:

 if self.allow_reuse_address:
     self.socket.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)

Answer 4

A simple solution that worked for me is to close the Terminal and restart it.

Answer 5

Nothing worked for me except running a subprocess with this command, before calling HTTPServer(('', 443), myHandler):

kill -9 $(lsof -ti tcp:443)

Of course this is only for linux-like OS!

Answer 6

because you trying to run service in same port that is already running.

some time its happen because your service is not stopped in process stack. you have to kill them

no need to install anything here is the one line command to kill all running python processes.

for Linux based OS:

Bash:

kill -9 $(ps -A | grep python | awk '{print $1}')

Fish:

kill -9 (ps -A | grep python | awk '{print $1}')