NUM_RECV_PER_SELECT
static struct mmsghdr msgs[NUM_RECV_PER_SELECT];
static struct iovec iovecs[NUM_RECV_PER_SELECT];
static struct query *queries[NUM_RECV_PER_SELECT];
for (int i = 0; i < NUM_RECV_PER_SELECT; i++) {
for (i = 0; i < NUM_RECV_PER_SELECT; i++) {
recvcount = nsd_recvmmsg(fd, msgs, NUM_RECV_PER_SELECT, 0, NULL);