采用tcp/ip服务器断开后，客户端不断开，接收数据为空咋办？

Question

本帖最后由 bcc222 于 2010-11-11 09:20:46 编辑

Answer 1

int CSocketBlockClient::ReceiveMsg_C(char *buff)
{
char tmp[1024];//没必要使用清1024个0浪费CPU
int ret=recv(m_hSocket,tmp,1024,0);//问题处
//if(ret==SOCKET_ERROR)//不是这么判断的
if (ret <= 0)
{
closesocket(m_hSocket);
return ret;
}}memcpy(buff,tmp,ret);
tmp[ret] = 0;//结束符,别忘记了,对于传文本的时候有用.
return ret;//实际收取的字符数.
}

Answer 2

// select mode 
#define SELECT_MODE_READY   0x001
#define SELECT_MODE_WRITE    0x002// select return codes 
#define SELECT_STATE_READY         0
#define SELECT_STATE_ERROR         1
#define SELECT_STATE_ABORTED       2
#define SELECT_STATE_TIMEOUT       3#ifdef WIN32
    #include <winsock2.h>
    #pragma comment(lib, "ws2_32.lib")
    #pragma warning(disable:4786)
    #pragma warning(disable:4996)
    #define SocketLen int
#else
    //network
    #include <sys/socket.h>
    #include <netinet/in.h>
    #include <arpa/inet.h>    
    #include <netinet/tcp.h>
    #include <netdb.h>
#endif
int CMySocket::BlockReceive(SOCKET sock, LPCSTR pBuffer, int readSize, int nTimeOut)
{
    int selectState;
    int recvSize;
    
    selectState = Select(sock, SELECT_MODE_READY, nTimeOut);
    if (SELECT_STATE_TIMEOUT == selectState)
        return 0;
    
    if (SELECT_STATE_READY == selectState)
    {
        recvSize = recv(sock, (char*)pBuffer, readSize, 0);
        if (recvSize <= 0)
            return -1;
        return recvSize;
    }
    return -1;
}
int CMySocket::BlockSend(SOCKET sock, LPCSTR pBuffer, int writeSize, int nTimeOut)
{
    int selectState = 0;
    int sendSize = 0;
    
    selectState = Select(sock, SELECT_MODE_WRITE, nTimeOut);
    if (selectState == SELECT_STATE_TIMEOUT)
        return 0;
    
    if (selectState == SELECT_STATE_READY)
    {
        sendSize = send(sock, (char*)pBuffer, writeSize, 0);
        if (sendSize <= 0)
            return -1;
        return sendSize;
    }    
    
    return -1;
}