Windows 7中的UDP广播 – 它有用吗？

unsigned long broadcastAddr = inet_addr("192.168.10.0") | ~(inet_addr("255.255.240.0"));

然后工作正常,我只是想使用首选的INADDR_BROADCAST / 255.255.255.255方法.

<snip>
SOCKET sockfd;
int broadcast = 1;

WSADATA wsaData;    // Windows socket

// Initialize Winsock
if (WSAStartup(MAKEWORD(2,2),&wsaData) == SOCKET_ERROR) {
    perror("WinSock Error");
    getc(stdin);
    exit(EXIT_FAILURE);
}
if ((sockfd = socket(AF_INET,SOCK_DGRAM,IPPROTO_UDP)) == -1) {
    perror("Socket Error");
    getc(stdin);
        exit(1);
}

if ((setsockopt(sockfd,SOL_SOCKET,SO_BROADCAST,(char *)&broadcast,sizeof(broadcast))) == SOCKET_ERROR) {
    perror("Setsockopt - SOL_SOCKET");
    getc(stdin);
    exit(1);
}

struct sockaddr_in recvaddr;
recvaddr.sin_family = AF_INET;
recvaddr.sin_port = htons(PORT);
recvaddr.sin_addr.s_addr = htonl(INADDR_BROADCAST);
memset(recvaddr.sin_zero,'\0',sizeof(recvaddr.sin_zero));

int numbytes = 0;
while ((numbytes = sendto(sockfd,greet,strlen(greet),MSG_DONTROUTE,(struct sockaddr *)&recvaddr,sizeof(struct sockaddr_in))) != -1) {
        printf("Sent a packet %d\n",numbytes);
        Sleep(100);
}