Re: [Boost-users] boost::Asio async_accept not throwing exception

Subject: Re: [Boost-users] boost::Asio async_accept not throwing exception
From: Igor R (boost.lists_at_[hidden])
Date: 2010-11-21 16:59:29

> Acceptor.async_accept(NewConnection->socket(),boost::bind(&TCPServer::HandleAccept,this,
> NewConnection,boost::asio::placeholders::error));
> Â Â Â  }
> Â Â Â  catch(std::exception& e)
> Â Â Â  {
> Â Â Â Â Â Â  cout<<"exception"<<endl;
> Â Â Â  }
> }
>
> Another program is already listening on the port "13" (A service version of
> the same program). When this new program tries to listen (async_accept) on
> port "13", no exception is thrown!.
>
> How can I check weather the port is already open?

async_XXX functions do not throw, they guarantee that the completion
handler will always be invoked. So what you should check is the
error_code in your completion handler.