Message 143802 - Python tracker

Message143802

Author	Alexander.Belopolsky
Recipients	Alexander.Belopolsky, Arfrever, belopolsky, jcea, khenriksson, larry, lars.gustaebel, loewis, mark.dickinson, nadeem.vawda, r.david.murray, rosslagerwall, skrah, vstinner
Date	2011-09-09.21:22:37
SpamBayes Score	6.7766264e-06
Marked as misclassified	No
Message-id	<CAP7h-xaBOV=FZBk67h89y8_c8RUDrojtAQ78jT=NOHhNuGL_GQ@mail.gmail.com>
In-reply-to	<1315601453.24.0.856996725809.issue11457@psf.upfronthosting.co.za>

Content
On Fri, Sep 9, 2011 at 4:50 PM, Larry Hastings <report@bugs.python.org> wrote: .. > I think a pair of integers is a poor API. It ties the value of the fractional part to nanoseconds. What happens > when a future filesystem implements picosecond resolution? If history repeats, struct stat will grow new st_xtimesuperspec fields, st_xtimespec will become a macro expanding to st_xtimesuperspec.tv_picosec and we will get a request to support that in os.stat(). I don't see why this conflicts with stat_result.st_xtimespec returning a (sec, nsec) tuple. If we will ever have to support higher resolution, stat_result will grow another member with a (sec, picosec) or whatever will be appropriate value. > And then later goes to femtoseconds? Same thing. > Or some platform chooses another divisor (2**32)? Unlikely, but C API will dictate Python API if this happens.

Content

On Fri, Sep 9, 2011 at 4:50 PM, Larry Hastings <report@bugs.python.org> wrote:
..
> I think a pair of integers is a poor API.  It ties the value of the fractional part to nanoseconds.  What happens
> when a future filesystem implements picosecond resolution?

If history repeats, struct stat will grow new st_xtimesuperspec
fields, st_xtimespec will become a macro expanding to
st_xtimesuperspec.tv_picosec and we will get a request to support that
in os.stat().  I don't see why this conflicts with
stat_result.st_xtimespec returning a (sec, nsec) tuple.  If we will
ever have to support higher resolution,  stat_result will grow another
member with a (sec, picosec) or whatever will be appropriate value.

>  And then later goes to femtoseconds?

Same thing.

>  Or some platform chooses another divisor (2**32)?

Unlikely, but C API will dictate Python API if this happens.

History
Date	User	Action	Args
2011-09-09 21:22:41	Alexander.Belopolsky	set	recipients: + Alexander.Belopolsky, loewis, jcea, mark.dickinson, belopolsky, lars.gustaebel, vstinner, larry, nadeem.vawda, Arfrever, r.david.murray, skrah, rosslagerwall, khenriksson
2011-09-09 21:22:38	Alexander.Belopolsky	link	issue11457 messages
2011-09-09 21:22:37	Alexander.Belopolsky	create