A wait on an equeue that holds socket events now blocks in poll/WSAPoll on
those sockets plus a per-thread loopback wake socket, instead of rechecking
every millisecond. Adding, triggering or deleting an event and closing the
equeue wake the blocked waiters. Closing a socket removes its read and write
events, as on FreeBSD. A read event also reports EV_EOF once the peer has
shut down its sending side.
sceKernelAddReadEvent/DeleteReadEvent and sceKernelAddWriteEvent/
DeleteWriteEvent register EVFILT_READ and EVFILT_WRITE events on guest
sockets. The equeue polls the host socket for readiness on each wait
and reports the readable byte count or the send buffer size in data,
with EV_EOF on hang-up or error.
kjhq