if (FD_ISSET(cluster_sockfd, &r))
{
int size;
size = recvfrom(cluster_sockfd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen);
processcluster(buf, size, addr.sin_addr.s_addr);
}
if (FD_ISSET(cluster_sockfd, &r))
{
int size;
size = recvfrom(cluster_sockfd, buf, sizeof(buf), MSG_WAITALL, (void *) &addr, &alen);
processcluster(buf, size, addr.sin_addr.s_addr);
}