今天怎么也搞不明白心跳机制判断网络是否断开,网上没找不到相应的代码,只好写了下面的这个,
但是问题又来了,每当到代码中红色的那里就再也不动了,不知道为什么?
我想要的结果是:
客户端就是直接连接服务端,然后一个recv(),由于下面的代码没有send()所以客户端一直等待,这时我把客户端关掉,叫下面的代码显示用户已经断线.
要想得到说的效果该怎么改?
问题代码:
#include <stdio.h>
#include <WinSock2.h>
#pragma comment( lib, "ws2_32.lib" )
typedef struct tcp_keepalive {
u_long onoff;
u_long keepalivetime;
u_long keepaliveinterval;
}tcp_keepalive,*ptcp_keepalive;
#define SIO_KEEPALIVE_VALS _WSAIOW(IOC_VENDOR,4)
void main()
{
WORD wVersionRequested;
WSADATA wsaData;
int err;
wVersionRequested = MAKEWORD( 1, 1 );
err = WSAStartup( wVersionRequested, &wsaData );
if ( err != 0 )
{
return;
}
if ( LOBYTE( wsaData.wVersion ) != 1 ||
HIBYTE( wsaData.wVersion ) != 1)
{
WSACleanup();
return;
}
SOCKET sockSrv=socket(AF_INET,SOCK_STREAM,0);
SOCKADDR_IN addrSrv;
addrSrv.sin_addr.S_un.S_addr =htonl(INADDR_ANY);
addrSrv.sin_family =AF_INET;
addrSrv.sin_port =htons(6000);
bind(sockSrv,(sockaddr*)&addrSrv,sizeof(SOCKADDR));
listen(sockSrv,SOMAXCONN);
SOCKADDR_IN addrClient;
int len=sizeof(SOCKADDR);
SOCKET sockconn=accept(sockSrv,(SOCKADDR*)&addrClient,&len);
tcp_keepalive InKeepAlive; //, OutKeepAlive;
const char chOpt = 1;
DWORD dw;
HANDLE hCompletionPort = CreateIoCompletionPort( (HANDLE)sockconn, NULL, 0, 0 );
int iRet = setsockopt(sockconn,SOL_SOCKET,SO_KEEPALIVE,(char *)&chOpt,sizeof(int));
if ( iRet == SOCKET_ERROR )
{
printf( "Error Setting!\n" );
}
InKeepAlive.onoff = 1;
InKeepAlive.keepalivetime = 3000;
InKeepAlive.keepaliveinterval = 1;
if ( WSAIoctl( sockconn, SIO_KEEPALIVE_VALS, (LPVOID)&InKeepAlive, sizeof( tcp_keepalive ), \
NULL, 0, &dw, NULL, NULL ) == SOCKET_ERROR )
{
printf( "WSAIoctl Error!\n" );
closesocket(sockconn);
return;
}
char buff[100];
sprintf(buff,"Welcome %s to here",inet_ntoa(addrClient.sin_addr ));
printf( "%s\n", buff );
while(1)
{
BOOL bRet = FALSE;
DWORD dwTrans = 0;
DWORD dwKey = 0;
LPOVERLAPPED lpOverlapped;
[COLOR=red]bRet = GetQueuedCompletionStatus( hCompletionPort, &dwTrans, &dwKey, &lpOverlapped, INFINITE );[/COLOR]
if ( bRet == FALSE )
{
//对方已经断线
printf( "对方已经断线\n" );
closesocket(sockconn);
return;
}
}
}
[课程]Android-CTF解题方法汇总！
