time module question - time zones

[Eric Wertman]

Sorry, my time zone is +4, not minus 4, which means that something
else is causing my source data to be in the future.  I still do need
to understand where the time routines determine the time zone offset,
so I can be sure I'm passing around the neutral value.

Thanks!


On Wed, May 21, 2008 at 12:23 PM, Eric Wertman <ewertman at gmail.com> wrote:
> I tend to deal with dates a lot in different formats and places...
> typically I'll convert them to a time tuple with strptime(), and pass
> them around like that before I need to write them back out.
>
> One set of time/dates I'm getting are in UTC, but the string doesn't
> say that specifically.  So I do this..  I had expected the outcome to
> be offset properly (I'm EST5EDT).  But I'm obviously missing
> something:
>
> #!/usr/bin/env python
>
> import time
>
> utc_str = '2008-05-10 03:05:00 UTC'
>
> d = time.strptime(utc_str,'%Y-%m-%d %H:%M:%S %Z')
> t = time.mktime(d)
>
> print d
> print time.gmtime(t)
> print time.localtime(t)
>
> output :
>
> (2008, 5, 10, 3, 5, 0, 5, 131, 0)
> (2008, 5, 10, 8, 5, 0, 5, 131, 0)
> (2008, 5, 10, 4, 5, 0, 5, 131, 1)
>
>
> I believe that I should be getting (2008, 5, 9, 23, 5, 0, 5, 130, 1)
> out of one of those, since the original 3:05am time was UTC, and my TZ
> is currently -4.  Does that make sense?  I didn't even think I needed
> to do any business with time.localtime() and time.gmtime().  I
> expected  time.strftime() to return the locale appropriate time, but
> it didn't.
>
> TIA
>
> Eric
>