应该是很简单的问题，怎么判断一个socket是否处于连接状态

[artmouse]

如题！

[huangwc]

这个应该很难区别把
你可以通过判断socket函数操作的返回值或者判断指定socket是否有效试试.

[yangng]

//m_hSocket 是SOCKET 你所要判断的
BOOL HasConnectionDropped(void)
{
BOOL bConnDropped = FALSE;
INT iRet = 0;
BOOL bOK = TRUE;

if (m_hSocket == INVALID_SOCKET)
return TRUE;

struct timeval timeout = { 0, 0 };
fd_set readSocketSet;

FD_ZERO(&readSocketSet);
FD_SET(m_hSocket, &readSocketSet);

iRet = ::select(0, &readSocketSet, NULL, NULL, &timeout);
bOK = (iRet > 0);

if(bOK)
{
bOK = FD_ISSET(m_hSocket, &readSocketSet);
}

if(bOK)
{
CHAR szBuffer[1] = "";
iRet = ::recv(m_hSocket, szBuffer, 1, MSG_PEEK);
bOK = (iRet > 0);
if(!bOK)
{
INT iError = ::WSAGetLastError();
bConnDropped = (( iError == WSAENETRESET) ||
(iError == WSAECONNABORTED) ||
(iError == WSAECONNRESET) ||
(iError == WSAEINVAL) ||
(iRet == 0));
}
}
return(bConnDropped);
}