使用套接字

Question

使用套接字send 的时候发送结构strict xx{
 short head;
}send(server,(char*)xx,sizeof(xx),0);接的时候怎么接.服务器端提示收到信息了,.但是读取的时候会提示读取冲突.应该怎么读.可以给个    详细的例子   吗?========================================================问题二:为什么 我的服务器端只能接收一个客户端连接?windows socket 编程

Answer 1

#pragma pack 1
typedef struct _tagMyStruct{
  short head;
}MyStruct, *LPMyStruct;
#pragma pack发送(Client端):MyStruct A;
A.head = 100;
char *P = (char *)&A;
int len = sizeof(A);
while (len){
  int ret = send(Server, P, len, 0);
  if(SOCKET_ERROR == ret){
    count<<"send过程发生错误:"<<WSAGetLastError()<<endl;
    break;
  }
  if(!ret){
    count<<"send过程发生中连接已断开!"<<endl;
    break;
  }
  len -= ret;
  P += ret;
  if(!len){
    count<<"数据发送完毕."<<endl;
  }
}
监听(Server端):WSAData wsaData;
if(WSAStartup(MAKEWORD(1,1), &wsaData)){
  count<<"WSAStartup 失败,错误号:"<<WSAGetLastError()<<endl;
  return;
}SOCKET sock = socket(PF_INET,
     SOCK_STREAM,
                     0);
if(INVALID_SOCKET == sock){
  count<<"调用socket失败:"<<WSAGetLastError()<<endl;
  WSACleanup();
  return;
}
const int port = 1234;
struct sockaddr_in local;
memset(&local, 0, sizeof(local));
local.sin_addr.s_addr = htonl(INADDR_ANY);
local.sin_family = AF_INET;
local.sin_port = htons(port);//监听端口
if(bind(sock, (struct sockaddr*)&local, sizeof(local)) == SOCKET_ERROR){
  count<<"调用bind到端口"<<port<<"失败，错误号:"<<WSAGetLastError()<<endl;
  closesocket(sock);
  WSACleanup();
  return;
}if(listen(sock, SOMAXCONN)==SOCKET_ERROR){
  count<<"调用listen失败，错误号:"<<WSAGetLastError()<<endl;
  closesocket(sock);
  WSACleanup();
  return;
}while(1){
  struct sockaddr_in remote_addr;
  memset(&remote_addr, 0, sizeof(sockaddr));
  int addr_len = sizeof(sockaddr);
  SOCKET sock_client = accept(sock, (struct sockaddr FAR*)&remote_addr, &addr_len);
  if(sock_client == INVALID_SOCKET){
    wsa_err = WSAGetLastError();
    switch(wsa_err){
      WSANOTINITIALISED: //
        return; 
      WSAECONNRESET: 
      WSAEFAULT:
      WSAEINPROGRESS:
      WSAEMFILE:
      WSAENOBUFS:
      WSAEWOULDBLOCK:
        continue; 
      WSAEINTR:
      WSAEOPNOTSUPP:
      WSAENETDOWN:// The network subsystem has failed.
      WSAEINVAL://The listen function was not invoked prior to accept.
        closesocket(sock);
      WSAENOTSOCK:
        WSACleanup(); 
        return;  
    }
  }
  count<<"有一个客户端连接过来:"<<sock_client<<endl;
  unsigned ThreadID;
  HANDLE pThread=(HANDLE)_beginthreadex(NULL,
                                         0,
                                         WorkerThread,
                                         &sock_client,
                                         CREATE_SUSPENDED,
                                         &ThreadID);
  if(!pThread){
    closesocket(sock_client);
    count<<"创建工作线程失败:"<<WSAGetLastError()<<endl;
    continue;
  }
  count<<"客户连接:"<<sock_client<<"交由线程:"<<ThreadID<<"处理!"<<endl;
  ResumeThread(pThread);//这里也要判断返回值
  CloseHandle(pThread);
}
closesocket(sock);
WSACleanup();
接收(Server端,采用多线程,用于处理多连接,如果要发送，与前面的Client端相似):unsigned WINAPI WorkerThread(LPVOID lpParam){
  SOCKET sock_client = (SOCKET) (*lpParam);
  WSAData wsaData;
  if(WSAStartup(MAKEWORD(1,1), wsaData)){
    closesocket(sock_client);
    _endthreadex(1);
    return 1;
  }  MyStruct A;
  char *P = (char *) &A;
  int len = sizeof(A);
  while(len){
    int ret = recv(sock_client, P, len, 0);
    if(SOCKET_ERROR == ret){
      count<<"Thread:"<<GetCurrentThreadId()<<" recv过程发生错误:"<<WSAGetLastError()<<endl;
      break;
    }
    if(!ret){
      count<<"Thread:"<<GetCurrentThreadId()<<" recv过程发生中连接已断开!"<<endl;
      break;
    }
    len -= ret;
    P += ret;
    if(len == 0)
      cout<<"Thread:"<<GetCurrentThreadId()<<" received from:"<<sock_client<<": A.head="<<A.head<<endl;
  }
  closesocket(sock_client);
  WSACleanup();
  _endthreadex(0);
}

Answer 2

   accept和receive函数

Answer 3

1、recv(client, (char*)xx, sizeof(xx), 0)，要检查返回值。
2、再执行accept。