[Python-Dev] Updates to PEP 471, the os.scandir() proposal

[Ben Hoyt]

>> Very much agreed that this isn't necessary for just readdir/FindNext
>> errors. We've never had this level of detail before -- if listdir()
>> fails half way through (very unlikely) it just bombs with OSError and
>> you get no entries at all.
>>
>> If you really really want this (again very unlikely), you can always
>> use call next() directly and catch OSError around that call.
>
> Agreed - I think the PEP should point this out explicitly, and show that the
> approach it takes offers a lot of flexibility in error handling from "just
> let it fail", to a single try/catch around the whole loop, to try/catch just
> around the operations that might call lstat(), to try/catch around the
> individual iteration steps.

Good point. It'd be good to mention this explicitly in the PEP and
have another example or two of the different levels of errors
handling.

> os.walk remains the higher level API that most code should be using, and
> that has to retain the current listdir based behaviour (any error = ignore
> all entries in that directory) for backwards compatibility reasons.

Yes, definitely.

-Ben