You probably mean one of the latest development releases of ASIO... It's not part of Boost, so there're low chances that you'll get an answer here. You'd better ask this question at some asio-specific forum/list. 2008/8/7, Jean-Sebastien Stoezel :

Hi,

While I've been able to implement non-blocking reads on sockets, using boost::asio::read and boost::asio::socket_base::bytes_readable (only reading whern there's data available), I'm having troubles implementing non-blocking reads on serial_port stream object.

Any idea how to do?

Thanks! Jean