[Python-Dev] thread semantics for file objects

["Martin v. Löwis"]

stelios xanthakis wrote:
> I think that when two threads write to the same fd without 
> syncronization, the result is not
> deterministic anyway. In the case they are reading from the same fd, 
> even worse! (and therefore
> the input cannot be useful to any serious algorithm)

Yes, but we are not talking about the same fd. Instead, we talk about
the same FILE*. A thread-safe libc guarantees (AFAIK) that the data
passed to fwrite are appended as a whole. This, in turn, means that
the data passed to Python's file.write are also appended as a whole.

I'm pretty sure this property also holds on Windows.

Regards,
Martin