UDP实现局域网内的广播

// Server#include <stdio.h>#include <winsock.h>#pragma comment(lib, "wsock32.lib")int main(int argc, char* argv[]){WSADATA wsaData;SOCKET sockListener;SOCKADDR_IN sin, saUdpServ;BOOL fBroadcast = TRUE;char sendBuff[1024];int nSize;int nCount = 0;if (WSAStartup(MAKEWORD(1, 1), &wsaData) != 0)// initialize WinSocket{printf("Failed to initialize windows socket!/n");return -1;}sockListener = socket(PF_INET, SOCK_DGRAM, 0);setsockopt(sockListener, SOL_SOCKET, SO_BROADCAST, (CHAR*)&fBroadcast, sizeof(BOOL));sin.sin_family = AF_INET;sin.sin_port = htons(0);sin.sin_addr.s_addr = htonl(INADDR_ANY);if (bind(sockListener, (SOCKADDR*)&sin, sizeof(sin)) != 0){printf("failed to bind socket to local port!/n");return -1;}saUdpServ.sin_family = AF_INET;saUdpServ.sin_addr.s_addr = htonl(INADDR_BROADCAST);saUdpServ.sin_port = htons(7001);nSize = sizeof(SOCKADDR_IN);while (true){sprintf(sendBuff, "Message%d", nCount++);sendto(sockListener, sendBuff, lstrlen(sendBuff), 0, (SOCKADDR*)&saUdpServ, sizeof(SOCKADDR_IN));printf("%s/n", sendBuff);}return 0;}

// client#include <stdio.h>#include <winsock.h>#include <conio.h>#pragma comment(lib, "wsock32.lib")int main(int argc, char* argv[]){WSADATA wsaData;SOCKET sockListener;SOCKADDR_IN sin, saClient;char cRecvBuff[1024];int nSize, nbSize;int iAddrLen = sizeof(saClient);if (WSAStartup(MAKEWORD(1, 1), &wsaData) != 0){printf("Failed to initialize windows socket!/n");return -1;}sockListener = socket(AF_INET, SOCK_DGRAM, 0);sin.sin_family = AF_INET;sin.sin_port = htons(7001);sin.sin_addr.s_addr = htonl(INADDR_ANY);if (bind(sockListener, (SOCKADDR FAR*)&sin, sizeof(sin)) != 0){printf("Failed to bind socket to local port!/n");return -1;}while (true){nSize = sizeof(SOCKADDR_IN);if ((nbSize = recvfrom(sockListener, cRecvBuff, 1024, 0, (SOCKADDR FAR*)&saClient, &nSize)) == SOCKET_ERROR){printf("Receive Error!");break;}cRecvBuff[nbSize] = '/0';printf("%s/n", cRecvBuff);}return 0;}