- POLLRDBAND is reported by select(2) as errorfd, not readfd;
- POLLERR is not the same as errorfd of select(2);
- flags that are not requested should not be returned.
Change-Id: I9cb3c2c260ead5a2852a2fbbc10280c2b5b0dff9
- clear "revents" fields even when the call times out;
- do not call FD_ISSET with a negative file descriptor number.
Change-Id: I7aeaae79e73e39aed127a75495ea08256b18c182