[Python-Dev] POSIX [Fuzziness in io module specs]

[Antoine Pitrou]

Hello,

Pascal Chambon <pythoniks <at> gmail.com> writes:
> @pitrou: non-blocking IO in python ? which ones are you thinking about ?

I was talking about the existing support for non-blocking IO in the FileIO class
(look up EAGAIN in fileio.c), as well as in the Buffered* objects.

> If it's too late to modify the IO API, too bad, but I don't feel 
> comfortable with the "truncate" word.

It's certainly too late to modify the IO API only for naming purposes.

> And I don't like the fact that we 
> move the filepointer to prevent it from exceeding the file size,

I don't see what you mean:

>>> with open('foobar', 'wb') as f:
...   f.truncate(0)
... 
0
>>> os.stat('foobar').st_size
0
>>> with open('foobar', 'wb') as f:
...   f.truncate(16)
...   f.tell()
... 
16
16
>>> os.stat('foobar').st_size
16

> I had the feeling that IOErrors were for operations on file streams 
> (opening, writing/reading, closing...), whereas OSErrors were for 
> manipulations on filesystems (renaming, linking, stating...) and 
> processes.

Ok, but the distinction is certainly fuzzy in many cases. I have no problem with
trying to change the corner cases you mention, though.

Regards

Antoine.