Windows网络编程：Overlapped Event的基本使用

Windows网络编程：Overlapped Event的基本使用

Windows网络编程Overlapped Event基本使用，下面是一个简单的例子

#include  < winsock2.h >
#include  < windows.h >
#include  < stdio.h >

#pragma comment(lib,  " ws2_32.lib " )

#define  LISTEN_PORT 5080
#define  BUFF_SIZE   256

int  main( void )
{
    WSADATA wsaData;
     int  nRet;
    SOCKET listen_sock;
    SOCKADDR_IN listen_addr;
    SOCKET client_sock;
    SOCKADDR_IN client_addr;
     int  client_addr_len  =   sizeof (client_addr);
    WSAEVENT read_event;
    WSAOVERLAPPED client_overlapped;
     char  buff[BUFF_SIZE];
    WSABUF wsaBuf;
     int  recv_bytes  =   0 ;
    DWORD flags  =   0 ;
    DWORD index;

    nRet  =  WSAStartup(MAKEWORD( 2 , 2 ),  & wsaData);
     if ( 0   !=  nRet)
    {
        printf( " WSAStartup() failed, error:%d.\n " , WSAGetLastError());
         return   1 ;
    }

    listen_sock  =  socket(PF_INET, SOCK_STREAM, IPPROTO_TCP);
     if (INVALID_SOCKET  ==  listen_sock)
    {
        printf( " socket() failed, error:%d.\n " , WSAGetLastError());
         goto  retflag1;
    }

    listen_addr.sin_family  =  AF_INET;
    listen_addr.sin_addr.s_addr  =  htonl(INADDR_ANY);
    listen_addr.sin_port  =  htons(LISTEN_PORT);
    nRet  =  bind(listen_sock, (SOCKADDR * ) & listen_addr,  sizeof (listen_addr));
     if (nRet  ==  SOCKET_ERROR)
    {
        printf( " bind() failed, error:%d.\n " , WSAGetLastError());
        closesocket(listen_sock);
         goto  retflag1;
    }

    nRet  =  listen(listen_sock,  5 );
     if (SOCKET_ERROR  ==  nRet)
    {
        printf( " listen() failed, error:%d.\n " , WSAGetLastError());
        closesocket(listen_sock);
         goto  retflag1;
    }

    client_sock  =  accept(listen_sock, (SOCKADDR * ) & client_addr,  & client_addr_len);
     if (INVALID_SOCKET  ==  client_sock)
    {
        printf( " accept() failed, error:%d.\n " , WSAGetLastError());
        closesocket(listen_sock);
         goto  retflag1;
    }

    read_event  =  WSACreateEvent();
     if (WSA_INVALID_EVENT  ==  read_event)
    {
        printf( " WSACreateEvent() failed, error:%d.\n " , WSAGetLastError());
        closesocket(listen_sock);
        closesocket(client_sock);
         goto  retflag1;
    }

     while ( 1 )
    {
        memset( & client_overlapped,  0 ,  sizeof (client_overlapped));
        client_overlapped.hEvent  =  read_event;

        wsaBuf.buf  =  buff;
        wsaBuf.len  =  BUFF_SIZE;

         if (WSARecv(client_sock,  & wsaBuf,  1 ,  & recv_bytes,  & flags,  & client_overlapped, NULL)  ==  SOCKET_ERROR)
        {
             if (WSAGetLastError()  !=  WSA_IO_PENDING)
            {
                printf( " WSARecv failed, error:%d.\n " , WSAGetLastError());
            }
             else
            {
                printf( " WSARecv WSA_IO_PENDING.\n " );
            }
        }
         else
        {
            printf( " %s " , wsaBuf.buf);
        }

        index  =  WSAWaitForMultipleEvents( 1 ,  & read_event, FALSE, WSA_INFINITE, FALSE);
         while ( ! WSAResetEvent(read_event))
        {
            printf( " WSAResetEvent failed, error:%d.\n " , WSAGetLastError());
        }

        WSAGetOverlappedResult(client_sock,  & client_overlapped,  & recv_bytes, FALSE,  & flags);
         if (recv_bytes  <=   0 )
        {
            printf( " WSAGetOverlappedResult() socket close " );
            closesocket(client_sock);
            WSACloseEvent(read_event);
             break ;
        }

        printf( " %s " , wsaBuf.buf);
    }

    closesocket(listen_sock);

retflag1:

    nRet  =  WSACleanup();
     if ( 0   !=  nRet)
    {
        printf( " WSACleanup() failed, error:%d.\n " , WSAGetLastError());
         return   1 ;
    }
     return   0 ;
}