本文实例为大家分享了C语言UDP传输系统的具体代码，供大家参考，具体内容如下
/*加载库文件*/#pragma comment( lib, "ws2_32.lib" )/*加载头文件*/#include <winsock2.h>#include <ws2tcpip.h>#include <stdio.h>#include <stdlib.h>/*定义多播常量*/#define MCASTADDR "224.3.5.8"#define MCASTPORT 25000#define BUFSIZE 1024#define MCOUNT 10/*定义广播常量*/#define BCASTPORT 5050#define BCOUNT 10/*定义广播全局变量*/SOCKET socketBro;SOCKET socketRec;struct sockaddr_in addrBro;struct sockaddr_in addrRec;BOOL broadSendFlag;BOOL broadFlag;DWORD bCount;DWORD bcastAddr;short bPort;/*定义多播全局变量*/SOCKET socketMul;SOCKET sockJoin;struct sockaddr_in addrLocal;struct sockaddr_in addrMul;BOOL multiSendFlag;BOOL bLoopBack; BOOL multiFlag;DWORD dwInterface; DWORD dwMulticastGroup;DWORD mCount; short mPort; /*自定义函数*/void initial();void GetArgments(int argc, char **argv);void userHelpAll();void userHelpBro();void userHelpMul();void broadcastSend();void broadcastRec();void mulControl();void multicastSend();void multicastRec();/*初始化全局变量函数*/void initial(){ /*初始化广播全局变量*/ bPort = BCASTPORT; bCount = BCOUNT; bcastAddr = INADDR_BROADCAST; broadSendFlag = FALSE; broadFlag = FALSE; multiFlag = FALSE; /*初始化多播全局变量*/ dwInterface = INADDR_ANY; dwMulticastGroup = inet_addr(MCASTADDR); mPort = MCASTPORT; mCount = MCOUNT; multiSendFlag = FALSE; bLoopBack = FALSE;}/*参数获取函数*/void GetArgments(int argc, char **argv){ int i; /*如果参数个数小于2个*/ if(argc<=1) { userHelpAll(); return ; } /*获取广播选项*/ if(argv[1][0]=='-'&&argv[1][1]=='b') { /*广播标志设置为真*/ broadFlag = TRUE; for(i=2; i < argc ;i++) { if (argv[i][0] == '-') { switch (tolower(argv[i][1])) { /*如果是发送者*/ case 's': broadSendFlag = TRUE; break; /*广播的地址*/ case 'h': if (strlen(argv[i]) > 3) bcastAddr = inet_addr(&argv[i][3]); break; /*广播的端口号*/ case 'p': if (strlen(argv[i]) > 3) bPort = atoi(&argv[i][3]); break; /*广播(接收或者发送)的数量*/ case 'n': bCount = atoi(&argv[i][3]); break; /*其他情况显示用户帮助，终止程序*/ default: { userHelpBro(); ExitProcess(-1); } break; } } } return ; } /*获取多播选项*/ if(argv[1][0]=='-'&&argv[1][1]=='m') { /*多播标志设置为真*/ multiFlag = TRUE; for(i=2; i < argc ;i++) { if (argv[i][0] == '-') { switch (tolower(argv[i][1])) { /*如果是发送者*/ case 's': multiSendFlag = TRUE; break; /*多播地址*/ case 'h': if (strlen(argv[i]) > 3) dwMulticastGroup = inet_addr(&argv[i][3]); break; /*本地接口地址*/ case 'i': if (strlen(argv[i]) > 3) dwInterface = inet_addr(&argv[i][3]); break; /*多播端口号*/ case 'p': if (strlen(argv[i]) > 3) mPort = atoi(&argv[i][3]); break; /*环回标志设置为真*/ case 'l': bLoopBack = TRUE; break; /*发送(接收)的数量*/ case 'n': mCount = atoi(&argv[i][3]); break; /*其他情况，显示用户帮助，终止程序*/ default: userHelpMul(); break; } } } } return;}/*全局用户帮助函数*/void userHelpAll(){ printf("Please choose broadcast[-b] or multicast[-m] !\n"); printf("userHelpAll: -b [-s][p][-h][-n] | -m[-s][-h][-p][-i][-l][-n]\n"); userHelpBro(); userHelpMul();}/*广播用户帮助函数*/void userHelpBro(){ printf("Broadcast: -b -s:str -p:int -h:str -n:int\n"); printf(" -b Start the broadcast program.\n"); printf(" -s Act as server (send data); otherwise\n"); printf(" receive data. Default is receiver.\n"); printf(" -p:int Port number to use\n "); printf(" The default port is 5050.\n"); printf(" -h:str The decimal broadcast IP address.\n"); printf(" -n:int The Number of messages to send/receive.\n"); printf(" The default number is 10.\n");}/*多播用户帮助函数*/void userHelpMul(){ printf("Multicast: -m -s -h:str -p:int -i:str -l -n:int\n"); printf(" -m Start the multicast program.\n"); printf(" -s Act as server (send data); otherwise\n"); printf(" receive data. Default is receiver.\n"); printf(" -h:str The decimal multicast IP address to join\n"); printf(" The default group is: %s\n", MCASTADDR); printf(" -p:int Port number to use\n"); printf(" The default port is: %d\n", MCASTPORT); printf(" -i:str Local interface to bind to; by default \n"); printf(" use INADDRY_ANY\n"); printf(" -l Disable loopback\n"); printf(" -n:int Number of messages to send/receive\n"); ExitProcess(-1);}/*广播消息发送函数*/void broadcastSend(){ /*设置广播的消息*/ char *smsg="The message received is from sender!"; BOOL opt=TRUE; int nlen=sizeof(addrBro); int ret; DWORD i=0; /*创建UDP套接字*/ socketBro=WSASocket(AF_INET,SOCK_DGRAM,0,NULL,0,WSA_FLAG_OVERLAPPED); /*如果创建失败*/ if(socketBro==INVALID_SOCKET) { printf("Create socket failed:%d\n",WSAGetLastError()); WSACleanup(); return; } /*设置广播地址各个选项*/ addrBro.sin_family=AF_INET; addrBro.sin_addr.s_addr=bcastAddr; addrBro.sin_port=htons(bPort); /*设置该套接字为广播类型*/ if (setsockopt(socketBro,SOL_SOCKET,SO_BROADCAST,(char FAR *)&opt, sizeof(opt))==SOCKET_ERROR) /*如果设置失败*/ { printf("setsockopt failed:%d",WSAGetLastError()); closesocket(socketBro); WSACleanup(); return; } /*循环发送消息*/ while(i<bCount) { /*延迟1秒*/ Sleep(1000); /*从广播地址发送消息*/ ret=sendto(socketBro,smsg,256,0,(struct sockaddr*)&addrBro,nlen); /*如果发送失败*/ if(ret==SOCKET_ERROR) printf("Send failed:%d",WSAGetLastError()); /*如果发送成功*/ else { printf("Send message %d!\n",i); } i++; } /*发送完毕后关闭套接字、释放占用资源*/ closesocket(socketBro); WSACleanup();}/*广播消息接收函数*/void broadcastRec(){ BOOL optval = TRUE; int addrBroLen; char buf[256]; DWORD i=0; /*该地址用来绑定套接字*/ addrRec.sin_family=AF_INET; addrRec.sin_addr.s_addr=0; addrRec.sin_port=htons(bPort); /*该地址用来接收网路上广播的消息*/ addrBro.sin_family=AF_INET; addrBro.sin_addr.s_addr=bcastAddr; addrBro.sin_port=htons(bPort); addrBroLen=sizeof(addrBro); //创建UDP套接字 socketRec=socket(AF_INET,SOCK_DGRAM,0); /*如果创建失败*/ if(socketRec==INVALID_SOCKET) { printf("Create socket error:%d",WSAGetLastError()); WSACleanup(); return; } /*设置该套接字为可重用类型*/ if(setsockopt(socketRec,SOL_SOCKET,SO_REUSEADDR,(char FAR *)&optval, sizeof(optval))==SOCKET_ERROR) /*如果设置失败*/ { printf("setsockopt failed:%d",WSAGetLastError()); closesocket(socketRec); WSACleanup(); return; } /*绑定套接字和地址*/ if(bind(socketRec,(struct sockaddr *)&addrRec, sizeof(struct sockaddr_in))==SOCKET_ERROR) /*如果绑定失败*/ { printf("bind failed with: %d\n", WSAGetLastError()); closesocket(socketRec); WSACleanup(); return ; } /*从广播地址接收消息*/ while(i<bCount) { recvfrom(socketRec,buf,256,0,(struct sockaddr FAR *)&addrBro,(int FAR *)&addrBroLen); /*延迟2秒钟*/ Sleep(2000); /*输出接收到缓冲区的消息*/ printf("%s\n",buf); /*情况缓冲区*/ ZeroMemory(buf,256); i++; } /*接收完毕后关闭套接字、释放占用资源*/ closesocket(socketRec); WSACleanup();}/*多播控制函数*/void mulControl(){ int optval; /*创建UDP套接字，用于多播*/ if ((socketMul = WSASocket(AF_INET, SOCK_DGRAM, 0, NULL, 0, WSA_FLAG_MULTIPOINT_C_LEAF | WSA_FLAG_MULTIPOINT_D_LEAF | WSA_FLAG_OVERLAPPED)) == INVALID_SOCKET) { printf("socket failed with: %d\n", WSAGetLastError()); WSACleanup(); return ; } /*设置本地接口地址*/ addrLocal.sin_family = AF_INET; addrLocal.sin_port = htons(mPort); addrLocal.sin_addr.s_addr = dwInterface; /*将UDP套接字绑定到本地地址上*/ if (bind(socketMul, (struct sockaddr *)&addrLocal, sizeof(addrLocal)) == SOCKET_ERROR) /*如果绑定失败*/ { printf("bind failed with: %d\n", WSAGetLastError()); closesocket(socketMul); WSACleanup(); return ; } /*设置多播地址各个选项*/ addrMul.sin_family = AF_INET; addrMul.sin_port = htons(mPort); addrMul.sin_addr.s_addr = dwMulticastGroup; /*重新设置TTL值*/ optval = 8; /*设置多播数据的TTL(存在时间)值。默认情况下，TTL值是1*/ if (setsockopt(socketMul, IPPROTO_IP, IP_MULTICAST_TTL, (char *)&optval, sizeof(int)) == SOCKET_ERROR) /*如果设置失败*/ { printf("setsockopt(IP_MULTICAST_TTL) failed: %d\n",WSAGetLastError()); closesocket(socketMul); WSACleanup(); return ; } /*如果指定了返还选项*/ if (bLoopBack) { /*设置返还选项为假，禁止将发送的数据返还给本地接口*/ optval = 0; if (setsockopt(socketMul, IPPROTO_IP, IP_MULTICAST_LOOP, (char *)&optval, sizeof(optval)) == SOCKET_ERROR) /*如果设置失败*/ { printf("setsockopt(IP_MULTICAST_LOOP) failed: %d\n", WSAGetLastError()); closesocket(socketMul); WSACleanup(); return ; } } /*加入多播组*/ if ((sockJoin = WSAJoinLeaf(socketMul, (SOCKADDR *)&addrMul, sizeof(addrMul), NULL, NULL, NULL, NULL, JL_BOTH)) == INVALID_SOCKET) /*如果加入不成功*/ { printf("WSAJoinLeaf() failed: %d\n", WSAGetLastError()); closesocket(socketMul); WSACleanup(); return ; }}/*多播消息发送函数*/void multicastSend(){ TCHAR sendbuf[BUFSIZE]; DWORD i; int ret; mulControl(); /*发送mCount条消息*/ for(i = 0; i < mCount; i++) { /*将待发送的消息写入发送缓冲区*/ sprintf(sendbuf, "server 1: This is a test: %d", i); ret=sendto(socketMul, (char *)sendbuf, strlen(sendbuf), 0, (struct sockaddr *)&addrMul, sizeof(addrMul)); /*如果发送失败*/ if(ret==SOCKET_ERROR) { printf("sendto failed with: %d\n",WSAGetLastError()); closesocket(sockJoin); closesocket(socketMul); WSACleanup(); return ; } /*如果发送成功*/ else printf("Send message %d\n",i); Sleep(500); } /*关闭套接字、释放占用资源*/ closesocket(socketMul); WSACleanup();}/*多播消息接收函数*/void multicastRec(){ DWORD i; struct sockaddr_in from; TCHAR recvbuf[BUFSIZE]; int ret; int len = sizeof(struct sockaddr_in); mulControl(); /*接收mCount条消息*/ for(i = 0; i < mCount; i++) { /*将接收的消息写入接收缓冲区*/ if ((ret = recvfrom(socketMul, recvbuf, BUFSIZE, 0, (struct sockaddr *)&from, &len)) == SOCKET_ERROR) /*如果接收不成功*/ { printf("recvfrom failed with: %d\n",WSAGetLastError()); closesocket(sockJoin); closesocket(socketMul); WSACleanup(); return ; } /*接收成功，输出接收的消息*/ recvbuf[ret] = 0; printf("RECV: '%s' from <%s>\n", recvbuf,inet_ntoa(from.sin_addr)); } /*关闭套接字、释放占用资源*/ closesocket(socketMul); WSACleanup();}/*主函数*/int main(int argc, char **argv){ WSADATA wsd; initial(); GetArgments(argc, argv); /*初始化Winsock*/ if (WSAStartup(MAKEWORD(2, 2), &wsd) != 0) { printf("WSAStartup() failed\n"); return -1; } /*如果是执行广播程序*/ if(broadFlag) { /*以发送者身份发送消息*/ if(broadSendFlag) { broadcastSend(); return 0; } /*以接收者身份接收消息*/ else { broadcastRec(); return 0; } } /*如果是执行多播程序*/ if(multiFlag) { /*以发送者身份发送消息*/ if(multiSendFlag) { multicastSend(); return 0; } /*以接收者身份接收消息*/ else { multicastRec(); return 0; } } return 0;}
以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持。
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