TCP data rec timeout don't work for me - c++

Question

I have a boost async tcp client that need recevive data from server all time.
I want put there a time out that when don't arive data for n sec disconnect from server and try againg to connect.
and I use vc++.
void tcpclient::Connect(){
.....
socket_.async_connect(*iterator,boost::bind(&tcpclient::AfterConnection,shared_from_this(),boost::asio::placeholders::error));
}
void tcpclient::AfterConnection(const boost::system::error_code& error){
if (!error)
{
SetTimeout();
}
}
void tcpclient::SetTimeout(int sec = 1)
{
SOCKET native_sock = socket_.native();
int result = SOCKET_ERROR;
if (INVALID_SOCKET != native_sock)
{
struct timeval tv;
tv.tv_sec = sec;
tv.tv_usec = 0;
result = setsockopt(native_sock, SOL_SOCKET, SO_RCVTIMEO,(char *)&tv,sizeof(struct timeval));
i = GetLastError();
}
}
and I read like blow:
socket_.async_receive(boost::asio::buffer(buffer, 1024),
boost::bind(&tcpClient::handleReceive,
shared_from_this(),
boost::asio::placeholders::error,
buffer,
boost::asio::placeholders::bytes_transferred)
);
but when I try to simulate case that don't arive data connection stay etablished:
$netstat -ao
TCP 192.168.0.6:62836 192.168.0.5:telnet ESTABLISHED 2840
what is the problem why this happend?

Answer 1

Setting SO_RCVTIMEO causes otherwise-blocking calls to read to return with no data after waiting for the specified time, as a non-blocking socket would have done immediately.
So, the question is, what do you, or Boost, do when read returns an EWOULDBLOCK error? You need to show how you're doing the read; if Boost is handling it in an event loop (based on select or poll) it probably just waits for some data to become available.
If that's the case, a better approach is to register a timer callback with the event loop to fire every second or however often, and check whether you received some data during the previous second. The socket options won't help you with that.