[Boost-users] [asio] async_accept shares port?

HI! I've got another strange question, hope it is not very dumb. I'm launching two programs on my computer. Each tcp_acceptor in each program calls async_accept on one port and so is ready to accept connections. When I try to connect to the predefined port, I am connecting to the app that called async_accept later. As I thought, when trying to listen to port that is already accepting connections - another program will receive some error_code, but I do not see this in my case. Where is the mistake? Thanks!