c++ scoket

#include <stdio.h>
#include <winsock2.h>
#pragma comment(lib, "ws2_32.lib")
int  main()
{

// 初始化 Winsock.
    WSADATA wsaData;
    int iResult = WSAStartup( MAKEWORD(2,2), &wsaData );
    if ( iResult != NO_ERROR )
        printf("Error at WSAStartup()\n");

// 建立socket socket.
    SOCKET client;
    client = socket( AF_INET, SOCK_STREAM, IPPROTO_TCP );

    if ( client == INVALID_SOCKET )
    {
        printf( "Error at socket(): %ld\n", WSAGetLastError() );
        WSACleanup();
        return -1;
    }

// 连接到服务器.
    sockaddr_in clientService;

    clientService.sin_family = AF_INET;
    clientService.sin_addr.s_addr = inet_addr( "127.0.0.1" );
    clientService.sin_port = htons( 27015 );

    if ( connect( client, (SOCKADDR*) &clientService, sizeof(clientService) ) == SOCKET_ERROR)
    {
        printf( "Failed to connect.\n" );
        WSACleanup();
        return -1;
    }

// 发送并接收数据.
    int bytesSent;
    int bytesRecv = SOCKET_ERROR;
    char sendbuf[32] = "Client: Sending data.";
    char recvbuf[32] = "";

    bytesSent = send( client, sendbuf, strlen(sendbuf), 0 );
    printf( "Bytes Sent: %ld\n", bytesSent );

    while ( bytesRecv == SOCKET_ERROR )
    {
        bytesRecv = recv( client, recvbuf, 32, 0 );
        if ( bytesRecv == 0 || bytesRecv == WSAECONNRESET )
        {
            printf( "Connection Closed.\n");
            break;
        }
        if (bytesRecv < 0)
            return -1;
        printf( "Bytes Recv: %ld\n", bytesRecv );
    }

    return 0;
}