[Python-Dev] why duplicate output lines in verbose tests?

[Antoine Pitrou]

Guido van Rossum <guido <at> python.org> writes:
> 
> On Tue, Aug 12, 2008 at 11:32 AM, Bill Janssen <janssen <at> parc.com> wrote:
> >> Is it using fork()? Threads?
> >
> > No on fork(), yes on threads.
> 
> Hmm...  I don't believe that io.py is thread-safe. 

There is an issue open for the BufferedWriter + threads problem (which is
probably what causes Bill's problem above).
http://bugs.python.org/issue3476

As Martin suggested in this issue's comments, a simple fix would be to wrap most
methods with an instance-specific mutex. I don't know how that would affect
performance.

Regards

Antoine.