[Python-Dev] Possible py3k io wierdness

[Brian Quinlan]

Nick Coghlan wrote:
> Brian Quinlan wrote:
>> - you need the cooperation of your subclasses i.e. they must call
>>   super().flush() in .flush() to get correct close behavior (and this
>>   represents a backwards-incompatible semantic change)
> 
> Are you sure about that? Going by the current _pyio semantics that
> Antoine posted, it looks to me that it is already the case that
> subclasses need to invoke the parent flush() call correctly to avoid
> breaking the base class semantics (which really isn't an uncommon
> problem when it comes to writing correct subclasses).

As it is now, if you didn't call super().flush() in your flush override, 
then a buffer won't be flushed at the time that you expected.

With the proposed change, if you don't call super().flush() in your 
flush override, then the buffer will never get flushed and you will lose 
data when you close the file.

I'm not saying that it is a big deal, but it is a difference.

Cheers,
Brian