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The other night i was watching a google techtalk about python 3000 and
Guido mentioned some problems with the C standard io library.
In particular he highlighted an issue with switching between reading
and writing without flushing and the fact that it caused serious
errors. Not that i dont think its a good idea to write a new io
library, but I wondered if it was the same problem ive encounted.
It only happens on windows that i know off, but the fix is simple...
Assuming you have a hanlde to the file called "Handle" and a Flush()
method, the following logic for read and write will allow you to
detect and prevent the problem.
Add this to the Read() method before reading takes place:
if ( Handle && (Handle->_flag & _IORW) && (Handle->_flag & (_IOREAD |
_IOWRT)) == _IOWRT )
{
 Flush();
 Handle->_flag |= _IOREAD;
}
Add this to the Write() method before writing takes place:
if ( Handle && (Handle->_flag & _IORW) && (Handle->_flag & (_IOREAD |
_IOWRT)) == _IOREAD )
{
 Flush();
 Handle->_flag |= _IOWRT;
}
Emerson

It seems that python3.0 behaves better in this area, specially on
Windows. See the examples given in issue3207.
And since the 'file' type does not use FILE* anymore, the given
workaround is not necessary.