[boost] Error to convert to boost::asio::streambuf to raw buffer char *buffer

boost::asio::streambuf sb; char *raw = sb; error: cannot convert ‘boost::asio::streambuf {aka boost::asio::basic_streambuf<>}’ to ‘char*’ in initialization I've checked the boost::asio::streambuf reference, but could not find anything to fix it, appreciate any clues.