超简单的一个重叠io模型，重在学习理解

超简单的一个重叠io模型，重在学习理解

 #include "stdio.h"
#include "winsock2.h"
#pragma comment(lib,"ws2_32.lib")

int main(void)
{
 WSADATA wsa;
 WSAStartup(MAKEWORD(2,2),&wsa);
 SOCKET ListenSocket,AcceptSocket;
 WSAOVERLAPPED overlapped;
 WSAEVENT wsaevent;
 WSABUF buf;
 char buffer[50];
 memset(b,0,sizeof(b));
 memset(buffer,0,sizeof(buffer));
 unsigned long recvtotal=0;
 unsigned long flags=0;
 buf.buf=buffer;
 buf.len=sizeof(buffer)-1;
 ListenSocket=WSASocket(AF_INET,SOCK_STREAM,IPPROTO_TCP,NULL,NULL,WSA_FLAG_OVERLAPPED);
 if(ListenSocket==SOCKET_ERROR)
 {
  printf("create socket failed /n");
  return 0;
 }
 SOCKADDR_IN sAddr,cAddr;
 sAddr.sin_addr.S_un.S_addr=htonl(INADDR_ANY);
 sAddr.sin_family=AF_INET;
 sAddr.sin_port=htons(5124);
 if(bind(ListenSocket,(sockaddr *)&sAddr,sizeof(sockaddr))==SOCKET_ERROR)
 {
  printf("bind error /n");
  return 0;
 }
 listen(ListenSocket,1);
 int len=sizeof(sockaddr);
 AcceptSocket=accept(ListenSocket,(sockaddr *)&cAddr,&len);
 if(AcceptSocket==INVALID_SOCKET)
 {
  printf("accept failed ! /n");
 }
 int ret=0;
 wsaevent=WSACreateEvent();
 while(true){
 memset(buffer,0,sizeof(buffer));
 overlapped.hEvent=wsaevent;
 if((ret=WSARecv(AcceptSocket,&buf,1,&recvtotal,&flags,&overlapped,NULL))==SOCKET_ERROR)
 {
  printf("%d /n",WSAGetLastError());
  if(WSAGetLastError()!=WSA_IO_PENDING)
  {
  printf("WSARecv failed with error %d/n",WSAGetLastError());
  closesocket(AcceptSocket);
  return 0;
  }
 }
 int index;
 DWORD recved;
 index=WSAWaitForMultipleEvents(1,&wsaevent,FALSE,WSA_INFINITE,FALSE);
 if(index!=WSA_WAIT_FAILED)
 {
  WSAResetEvent(wsaevent);
 }
 WSAGetOverlappedResult(AcceptSocket,&overlapped,&recved,FALSE,&flags);

 if(recved==0 )
 {
  printf("client socket have closed /n");
  closesocket(AcceptSocket);
  return 0;
 }
 else
 {
  printf("%s /n",buffer);
 }
 }
 closesocket(AcceptSocket);
 WSACleanup();
 return 0;
}

 

很简单所以就没写注释了。