I've been aware of this since the very beginning. If you have a way of determining the flags which have been set on and open stream - please let me know. Robert Ramey "gtsml owevwr" <gtsml.owevwr@googlemail.com> wrote in message news:6e954aa60901090542v4fe9be4w5993fabe0e1e6c53@mail.gmail.com... Hi, I just spend a entire day to realize this code was wrong: std::ofstream ofs(filename.c_str()); boost::archive::binary_ oarchive oa(ofs); oa << (*this); And this one was right: std::ofstream ofs(filename.c_str(), std::ios::binary); boost::archive::binary_oarchive oa(ofs); oa << (*this); The consequence of the first code is a "stream_error" throw which doesn't say much about the problem. Instead, an exception should be thrown earlier on if the file is not in binary mode. thanks alot to all the boost contributors, Frank ------------------------------------------------------------------------------ _______________________________________________ Boost-users mailing list Boost-users@lists.boost.org http://lists.boost.org/mailman/listinfo.cgi/boost-users