[Python-Dev] PEP 410 (Decimal timestamp): the implementation is ready for a review

"Martin v. Löwis" martin at v.loewis.de
Thu Feb 16 11:14:57 CET 2012


Am 16.02.2012 10:51, schrieb Victor Stinner:
> 2012/2/16 "Martin v. Löwis" <martin at v.loewis.de>:
>>> Maybe an alternative PEP could be written that supports the filesystem
>>> copying use case only, using some specialized ns APIs? I really think
>>> that all you need is st_{a,c,m}time_ns fields and os.utime_ns().
>>
>> I'm -1 on that, because it will make people write complicated code.
> 
> Python 3.3 *has already* APIs for nanosecond timestamps:
> os.utimensat(), os.futimens(), signal.sigtimedwait(), etc. These
> functions expect a (seconds: int, nanoseconds: int) tuple.

I'm -1 on adding these APIs, also. Since Python 3.3 is not released
yet, it's not too late to revert them.

> If you consider that the float loss of precision is not an issue for
> nanoseconds, we should use float for os.utimensat(), os.futimens() and
> signal.sigtimedwait(), just for consistency.

I'm wondering what use cases utimensat and futimens have that are not
covered by utime/utimes (except for the higher resolution).

Keeping the "ns" in the name but not doing nanoseconds would be bad, IMO.

For sigtimedwait, accepting float is indeed the right thing to do.

In the long run, we should see whether using 128-bit floats
is feasible.

Regards,
Martin


More information about the Python-Dev mailing list