1 /* dgramrcv.c - receive from udp server
13 /* socket and bind stuff */
14 #include <sys/types.h>
15 #include <sys/socket.h>
18 #include <netinet/in.h>
21 #include <arpa/inet.h>
29 int main(int argc, char *argv[]) {
31 struct sockaddr_in target_addr;
32 int receive_bytes, write_bytes;
33 socklen_t target_addr_len,optlen;
36 printf("usage: %s <target-ip> <port>\n",argv[0]);
40 if((receive_fd=socket(AF_INET,SOCK_DGRAM,0)) == -1) {
41 printf("can't open socket.\n");
46 setsockopt(receive_fd,SOL_SOCKET,SO_BROADCAST,NULL,optlen);
48 memset(&target_addr,0,sizeof(target_addr));
49 target_addr.sin_family=AF_INET;
50 target_addr.sin_port=htons(atoi(argv[2]));
51 target_addr.sin_addr.s_addr=inet_addr(argv[1]);
52 target_addr_len=sizeof(target_addr);
55 while(receive_bytes>0) {
56 unsigned char buf[1000];
57 receive_bytes=recvfrom(receive_fd,buf,sizeof(buf),0,(struct sockaddr *)&target_addr,&target_addr_len);
58 write_bytes=write(1,buf,receive_bytes);
62 printf("connection closed ...\n");
63 printf("%d from %d total bytes written.\n",write_bytes,receive_bytes);