SSL_POLL_EVENT_OSB
if (item->revents & SSL_POLL_EVENT_OSB) {
processed_event = processed_event | SSL_POLL_EVENT_OSB;
#define SSL_POLL_EVENT_OS (SSL_POLL_EVENT_OSB | SSL_POLL_EVENT_OSU)
if ((events & SSL_POLL_EVENT_OSB) != 0
revents |= SSL_POLL_EVENT_OSB;