PFD_PIPE_DNS
pfd[PFD_PIPE_DNS].fd = ibuf_dns->fd;
pfd[PFD_PIPE_DNS].events = POLLIN;
pfd[PFD_PIPE_DNS].events |= POLLOUT;
if (nfds > 0 && (pfd[PFD_PIPE_DNS].revents & POLLOUT))
if (nfds > 0 && pfd[PFD_PIPE_DNS].revents & (POLLIN|POLLERR)) {