udp-protocol.rar_VC UDP

#pragma comment(lib, "ws2_32.lib") #include "windows.h" #include <stdio.h> #include <Winsock.h> #define Server_PORT 6000 #define MAXLINE 5096 //#define pleaseSendMessage 10 #define wan_ip "127.0.0.1" #define wan_PORT 8180 struct stMessage { unsigned int messageID; char messagebuf[MAXLINE]; }; void InitWinSock() { WSADATA wsaData; WORD wVersionRequested; int err; wVersionRequested=MAKEWORD(1,1); err = WSAStartup( wVersionRequested, &wsaData ); if ( err != 0 ) { // return; // } if(LOBYTE(wsaData.wVersion)!=1||HIBYTE(wsaData.wVersion)!=1) { WSACleanup(); return; } } void main(int argc, char* argv[]) { InitWinSock(); SOCKET sock=socket(AF_INET,SOCK_DGRAM,0); SOCKADDR_IN locale; if (sock==INVALID_SOCKET) { printf("socket creat error--exit!\n"); exit(-1); } memset(&locale,0,sizeof(locale)); locale.sin_family = AF_INET; locale.sin_port = htons(Server_PORT); locale.sin_addr.S_un.S_addr = htonl(INADDR_ANY); if (bind(sock,(struct sockaddr *)&locale,sizeof(locale))==SOCKET_ERROR) { printf("bind error !\n"); exit(-1); } SOCKADDR_IN sender; memset(&sender,0,sizeof(sender)); sender.sin_addr.S_un.S_addr=inet_addr(wan_ip); sender.sin_family=AF_INET; sender.sin_port=htons(wan_PORT); int addlen=sizeof(sender); // for(;;) // { // stMessage msgbuf; // memset(&msgbuf,0,sizeof(stMessage)); // // int n=recvfrom(sock,(char*)&msgbuf,sizeof(stMessage),0,(struct sockaddr *)&sender,&addlen); // printf("message ID:%s,message port:%d,message content:%s\n",inet_ntoa(sender.sin_addr),ntohs(sender.sin_port),msgbuf.messagebuf); // msgbuf.messageID = sender.sin_addr.S_un.S_addr; // if (strcmp(msgbuf.messagebuf,"exit")==0) // { // closesocket(sock); // exit(0); // } // else // { printf("send to c:\n"); while(1) { // char buf[]="aaaaa"; char a[5]={'a','b','c','d','e'}; for (int i=0;i<5;i++) { int sendnum=sendto(sock,(char *)&a[i],sizeof(a[i]),0,(struct sockaddr *)&sender,addlen); //int sendnum=sendto(sock,(char *)&buf,sizeof(buf),0,(struct sockaddr *)&sender,addlen); //printf("%s\n",buf); printf("%c\n",a[i]); unsigned int port=ntohs(sender.sin_port); if(sendnum<0) { printf("send error\n"); } // memset(&msgbuf,0,sizeof(msgbuf)); // } Sleep(500); } } //} closesocket(sock); WSACleanup(); }