Sockets in a Bind: Troubleshooting Port Exhaustion in Heroku's Routing Layer

The linked article does a much better job of explaining the problem. Just read this one: https://idea.popcount.org/2014-04-03-bind-before-connect/

That C code has a buffer overflow. Also they call atoi unnecessarily in each loop iteration.

A better solution would be relatively new socket option:

IP_BIND_ADDRESS_NO_PORT

This type of thing would not have been an issue 15 years ago. This is Richard Stevens socket programming 101.