I write a chat server using BSD socket, which is listen to
an specific port, say 1212. After the chat server is shutdown,
I want to execute the program again. But kernel will say that
the port 1212 is now unavailable. I have to wait for a while to
reuse the port 1212.

I am sure there's no other user using the same port on the
workstation.

Please tell me how to reuse the port.

thanks for help.