res_send.c

		*thisresplenp = recvfrom(pfd[0].fd, (char*)*thisansp,
					 *thisanssizp, 0,
					(struct sockaddr *)&from, &fromlen);
		if (__glibc_unlikely (*thisresplenp <= 0))       {
			if (errno == EINTR || errno == EAGAIN) {
				need_recompute = 1;
				goto wait;
			}
			Perror(statp, stderr, "recvfrom", errno);
			goto err_out;
		}