Socket listen doesn't unbind in C++ under linux

Question

I have a socket that listens on some port. I send the SIGSTOP signal to the thread that waits on the port (using accept) and terminate it. then I close the fd of the socket

Answer 1

Did you know that sockets are typically kept in a kind of limbo for a minute or two after you've finished listening on them to prevent communications intended for the previous process coming to yours? It's called the 'TIME_WAIT' state.

If you want to override that behaviour use setsockopt to set the SO_REUSEADDR flag against the socket before listening on it.