According to the FreeBSD Manual Page:
- When kevent() returns and if `flags` is EVFILT_READ, sockets which have previously been passed to listen() return when there is an incoming connection pending. `data` contains the size of the listen backlog.
So if an EVFILT_READ event reaches and it is the listen socket, we must accept `event->data` times. And for `ff_epoll` interface, we should continue to accept until it fails.
In the previous version, we only accept once when event reaches, it will cause listen queue overflow.
fengbojiang(姜凤波)