PFD_SENDER_IN
pfd[PFD_SENDER_IN].fd = fdin;
pfd[PFD_SENDER_IN].events = POLLIN;
(pfd[PFD_SENDER_IN].revents & POLLIN)) {
pfd[PFD_SENDER_IN].revents &= ~POLLIN;
if ((pfd[PFD_SENDER_IN].revents & POLLIN) ||