#include "unp.h" #define SAP_NAME "sap.mcast.net" /* default group name and port */ #define SAP_PORT "9875" void loop(int, socklen_t); int main(int argc, char **argv) { int sockfd; const int on = 1; socklen_t salen; struct sockaddr *sa; if (argc == 1) sockfd = Udp_client(SAP_NAME, SAP_PORT, (void **) &sa, &salen); else if (argc == 4) sockfd = Udp_client(argv[1], argv[2], (void **) &sa, &salen); else err_quit("usage: mysdr "); Setsockopt(sockfd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)); Bind(sockfd, sa, salen); Mcast_join(sockfd, sa, salen, (argc == 4) ? argv[3] : NULL, 0); loop(sockfd, salen); /* receive and print */ exit(0); }