Hi all, I have a class used as a Boost iostream: boost::iostreams::stream ms; The my_stream class implements a couple of extra methods (one example being to insert a block of data in the middle of the stream) however the stream does not get flushed before the call to these extra functions, which results in corrupted data: ms.write("1234", 4); ms.seekp(-2, std::ios::cur); ms->insert(2); // my_stream method This should result in "12__34", but unfortunately because of buffering, the insert() ends up happening before the write(), leaving you with just "1234". The problem is solved by flushing the cache all over the place: ms.write("1234", 4); ms.flush(); ms.seekp(-2, std::ios::cur); ms->insert(2); ms.flush(); However this isn't really ideal. I would rather the insert() function was able to flush itself before manipulating the underlying stream. Is this possible? Or am I going about this in entirely the wrong way?? ;-) Many thanks, Adam. -- class my_stream { public: typedef char char_type; typedef io::seekable_device_tag category; ...