Determining Time Zone on Win32

bsb has asked for the wisdom of the Perl Monks concerning the following question:

While porting code using DateTime to Windows I got a "Cannot determine local time zone" error. The code is like:

DateTime->from_epoch(epoch => $t, time_zone => 'local');
[download]

Is there a way to get a time zone from Windows? From strftime I got something semi-useful:

C:\>perl -MPOSIX=strftime -le "print strftime(q(%Z), localtime)"
AUS Central Standard Time
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I decided to calculate the difference between localtime and gmtime for now. Is there a better alternative?

#!/usr/bin/perl -w
use strict;
use DateTime::Duration;

my ($lh, $lm) = (localtime)[2,1];
my ($gh, $gm) = (gmtime)[2,1];

my $dur = DateTime::Duration->new( hours => ($lh-$gh), minutes => ($lm
+-$gm));
print sprintf "%+02.2d%02d\n", $dur->in_units('hours','minutes');
[download]

Thanks, Brad

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Re: Determining Time Zone on Win32 by ashokpj (Hermit) on May 10, 2006 at 06:47 UTC
Try this module Time::Piece This module replaces the standard localtime and gmtime functions with implementations that return objects. It does so in a backwards compatible manner, so that using localtime/gmtime in the way documented in perlfunc will still return what you expect you can also able find time different `$t1 - $t2; # returns Time::Seconds object $t1 - 42; # returns Time::Piece object $t1 + 533; # returns Time::Piece object` [download]	[reply] [d/l]
Re^2: Determining Time Zone on Win32 by bsb (Priest) on May 10, 2006 at 07:01 UTC
Time::Piece::tzoffset looks good, thanks `perl -MTime::Piece -le '$m=localtime->tzoffset->minutes; printf "%+02. +2d%02.2d\n", int($m/60), $m%60' +1000 # cmd.exe friendly perl -MTime::Piece -le "$m=localtime->tzoffset->minutes; printf qq(%+0 +2.2d%02.2d\n), int($m/60), $m%60" +1000` [download]	[reply] [d/l]