[Boost-users] Asio streambuf

Hiya, Does anyone know a way of reading from an asio::streambuf without removing the bytes? I'm using async_read() to get (possibly several) TCP messages, where each message is prefixed with a size field. If I can read the size without removing it from the buffer, I can check whether all the data was received and leave the size intact for the next handler if not. Any advice appreciated. Cheers, James