use POSIX;
print strftime("%Z", localtime()), "n";

use DateTime::TimeZone;

print DateTime::TimeZone->new( name => 'local' )->name();

use POSIX;
localtime();
my ($std, $dst) = POSIX::tzname();

my @lt = localtime(12*60*60);
my @gt = gmtime(12*60*60);
$tz = @lt[2] - @gt[2];
$tz_ = sprintf("%+03d:00", $tz); # for +02:00 format