套接字级别的IPv4和IPv6之间有什么区别吗？

I need to add IPv6 support to an existing socket-based application which currently only supports IPv4. To embrace the incoming era of IPv6, someone ordered me to add an IPv6 interface for the app and let the outside world to choose either the IPv4 interface or the IPv6 interface when trying to communicate with the app.I need to add IPv6 support to an existing socke