py3k buffered IO - flush() required between read/write?

[Genstein]

> With 3.2 on winxp, that is what I get with StringIO, text file, and
> bytes file (the first two with b's removed). I would expect the same on
> any system. If you get anything different, I would consider it a bug

Thanks Terry, you're entirely right there; I trimmed down my test case, 
asked for confirmation and have reported it as 
http://bugs.python.org/issue12062. Noted here in case anyone else trips 
over it.