I read in the documentation of Boost.Iostreams (at http://www.boost.org/doc/libs/1_35_0/libs/iostreams/doc/guide/asynchronous.h...) that "additional Device concepts will be required for full support of asynchronous i/o". Are there any ideas how these additional devices concepts will/should look like? I ask as I was trying to extend Boost.Asio and add support for C++ standard streams on the weekend. I came to the conclusion that this is impossible (as calls to C++ standard streams block and there is no way to interrupt a blocking call, at least not in a portable way). If there are any ideas though how to support asynchronous I/O with Boost.Iostreams I'd like to hear them. But I guess that would still mean that you can't use C++ standard streams (like std::cin) asynchronously? Boris