int fd = socket (AF_INET, SOCK_DGRAM, 0);
int yes = 1;
setsockopt(fd, SOL_SOCKET, SO_BROADCAST, &yes, sizeof(yes));
struct sockaddr_in server_to_add;
bzero (api_cmd_addr, sizeof(struct sockaddr_in));
server_to_add.sin_family = AF_INET;
server_to_add.sin_port = htons(1234);
server_to_add.sin_addr.s_addr = htonl(INADDR_BROADCAST);
char buf[5];
int res = sendto (fd, buf, 5, 0, &server_to_add, sizeof(struct sockaddr_in));
struct sockaddr_in server_rec_add;
byte receivedata[10];
while(1)
{
recvfrom(fd, receivedata, 10, 0, (struct sockaddr*)&server_rec_add, sizeof(struct sockaddr_in));
}
代码大概是这样子，最后发现回来的server_rec_add.sin_addr.s_addr是0，不知道为什么，请指教