Create a time value for using with localtime with the function timelocal from the (standard) Time::Local module.

#!/usr/bin/perl

use strict;
use warnings;

use Time::Local;

my $time = timelocal(0, 0, 0, 1, 3, 104);  # create time value
my $time_str = localtime($time);   # textual time representation
my ($dst) = (localtime($time))[8]; # fetch daylight savings time flag
if ($dst) {
    print "Daylight savings in effect on $time_str\n";
}
else {
    print "Daylight savings time not in effect on $time_str\n";
}
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The above example determines the DST for April 1, 2004. Changing the "create time value" statement to my $time = timelocal(0, 0, 0, 1, 1, 104);, it determines the DST for January 1, 2004.

Arjen