+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <netinet/ip.h>
+#include <arpa/inet.h>
+
+// #define NETWORK "233.121.29.%d" // workzone
+// #define NETWORK "233.83.45.%d" // nrk [tomt]
+// #define NETWORK "233.60.200.%d" // comvie [tomt]
+// #define NETWORK "239.193.0.%d" // uninett??
+// #define NETWORK "233.155.107.%d" // tv2
+#define NETWORK "224.67.163.%d" // blokk med stortinget i
+
+void join_group(int sock, int i)
+{
+ struct ip_mreqn mreq;
+ // char buf[256];
+ // snprintf(buf, 256, NETWORK, i);
+ // printf("%s\n", buf);
+ //mreq.imr_multiaddr.s_addr = inet_addr(buf);
+
+ mreq.imr_multiaddr.s_addr = i;
+ printf("%s\n", inet_ntoa(mreq.imr_multiaddr));
+ mreq.imr_address.s_addr = INADDR_ANY;
+ mreq.imr_ifindex = 0;
+ setsockopt(sock, IPPROTO_IP, IP_ADD_MEMBERSHIP, &mreq, sizeof(mreq));
+}
+
+void leave_group(int sock, int i)
+{
+ struct ip_mreqn mreq;
+ // char buf[256];
+ // snprintf(buf, 256, NETWORK, i);
+ // mreq.imr_multiaddr.s_addr = inet_addr(buf);
+ mreq.imr_multiaddr.s_addr = i;
+ mreq.imr_address.s_addr = INADDR_ANY;
+ mreq.imr_ifindex = 0;
+ setsockopt(sock, IPPROTO_IP, IP_DROP_MEMBERSHIP, &mreq, sizeof(mreq));
+}
+
+int main(int argc, char **argv)
+{
+ int sock = socket(PF_INET, SOCK_DGRAM, IPPROTO_UDP);
+ in_addr_t from = inet_addr(argv[1]);
+ in_addr_t to = inet_addr(argv[2]);
+ uint32_t skip = atoi(argv[3]);
+
+ for (in_addr_t i = ntohl(from); i <= ntohl(to); i += skip) {
+ join_group(sock, htonl(i));
+ if (i - ntohl(from) >= 10 * skip) {
+ leave_group(sock, htonl(i - 10 * skip));
+ }
+ usleep(200000);
+ }
+
+ sleep(2);
+}