#include "winsock2.h"#pragma     comment(lib,"WS2_32.LIB")int bufi;class mserver{private:      SOCKET ssock,csock;      sockaddr_in saddr,caddr;      int len;      char buf[4096];public:      mserver(){      }      mserver(int port,int maxclient){          saddr.sin_family=AF_INET;          saddr.sin_port=htons(port);          saddr.sin_addr.s_addr=INADDR_ANY;          ssock=socket(AF_INET,SOCK_STREAM,0);          if(ssock==INVALID_SOCKET){              printf("build socket error\n");          }          if(bind(ssock,(struct sockaddr*)&saddr,sizeof(saddr))==SOCKET_ERROR){              printf("socket bind fail\n");          }          len=sizeof(caddr);      }      void close(){          closesocket(ssock);          closesocket(csock);      }      void beginlisten(){          if(listen(ssock,10)==SOCKET_ERROR){              printf("listen fail\n");          }      }      void maccept(){          sockaddr a;          csock=accept(ssock,(struct sockaddr*)&caddr,&len);          if(csock==INVALID_SOCKET){              printf("accept fail : %d\n",WSAGetLastError());                     }          printf("client from %s connected\n",inet_ntoa(caddr.sin_addr));      }      int receive(){          memset(buf,0,4096);          if(recv(csock,buf,4096,0)==SOCKET_ERROR){              return 0;          }          printf("message received : %s\n",buf);          send(csock,buf,4096,0);          return 1;      }   };int _tmain(int argc, _TCHAR* argv[]){    WSADATA wsaData;      if (WSAStartup(MAKEWORD(2,1),&wsaData)){           printf("Winsock initializing fail\n");           WSACleanup();           return 0;      }      mserver server(12345,10);      server.beginlisten();      server.maccept();      while(server.receive());      server.close();      WSACleanup();      return 0;}

#include "winsock2.h"#pragma     comment(lib,"WS2_32.LIB")class mclient{private:      SOCKET sock;      sockaddr_in saddr;      int len;      char buf[4096];public:      mclient(){          sock=socket(AF_INET,SOCK_STREAM,0);          len=sizeof(saddr);      }      bool mconnect(char* addr,int port){          saddr.sin_family=AF_INET;          saddr.sin_port=htons(port);          saddr.sin_addr.s_addr=inet_addr(addr);          if(connect(sock,(struct sockaddr*)&saddr,len)==SOCKET_ERROR){              printf("connect fail : %d",WSAGetLastError());              return false;          }          return true;      }      void close(){          closesocket(sock);      }      void msend(char* mes){          send(sock,mes,strlen(mes),0);      }      bool receive(){          memset(buf,0,4096);          if(recv(sock,buf,4096,0)==SOCKET_ERROR){              return false;          }          else{              printf("received from server : %s\n",buf);              return true;          }      }};int main(){    while(1){      WSADATA wsaData;      if (WSAStartup(MAKEWORD(2,1),&wsaData)){           printf("Winsock initializing fail\n");           WSACleanup();           return 0;      }      mclient a;      if(!a.mconnect("127.0.0.1",12345)){          return 0;      }      char buf[1024];      while(scanf("%s",buf)){          if(strcmp(buf,"quit")==0){              break;          }          a.msend(buf);          a.receive();      }      a.close();      WSACleanup();    }      return 0}