CopyingInputStreamAdaptor and async socket read

[SN]

I would like to use CopyingInputStreamAdaptor to read asynchronously from a socket.

CopyingInputStreamAdaptor::Next invokes Read on copying_stream_ and expects to receive the number of bytes read as the return value of the function.

This works fine when I do a sync read. Is it possible to use this adaptor to an async read using boost asio?

Thanks
Shweta