There is no standard provision to find out the actual backlog value on this platform.
참고: The maximum number passed to the backlog parameter highly depends on the underlying platform. On linux, it is silently truncated to SOMAXCONN. On win32, if passed SOMAXCONN, the underlying service provider responsible for the socket will set the backlog to a maximum reasonable value. There is no standard provision to find out the actual backlog value on this platform.