The funtion - Date_ConvTZ is not working correctly when converting from EST to CST

[mangrove]

The Date_ConvTZ function from Date::Manip is not working correctly on version 6.52 which is working fine with version 5.42

#!/usr/local/bin/perl

use strict;
use warnings;
use POSIX;
use Date::Manip;
use Data::Dumper;

my $now = ParseDate( "now" );
print "NOW: $now\n";
my $today = ParseDate( "-1 hour" );
print "today:$today\n";
        my $npadate = UnixDate( $today, "%Y%m%d" );
        #my $npahour = UnixDate( $today, "%H" );


        #they want file date/time in central time............
        print "TODAY II: $today\n";
        my $fd = Date_ConvTZ( $today, "EST", "CST" );
        print "FD: $fd\n";
        my $yest = DateCalc( $fd, "-1 day" );
        $yest = UnixDate( $yest, "%Y%m%d" );
        print "yest:$yest\n";
        my $filedate = UnixDate( $fd, "%Y%m%d" );
        my $filehour = UnixDate( $fd, "%H" );
        print "filedate:$filedate, filehour:$filehour\n";

output:- NOW: 2017050112:32:01 today:2017050111:32:01 TODAY II: 2017050111:32:01 FD: 2017050200:32:01 yest:20170501 filedate:20170502, filehour:00

[1nickt]

From the doc to Date::Manip:

VERSION 5 AND VERSION 6

Date::Manip version 6.00 was a complete rewrite of the module (for more information, please refer to the Date::Manip::Changes5to6 document).

The document linked to in that Readme contains all you need to know about the changes to TimeZone handling in Date::Manip, including at http://search.cpan.org/~sbeck/Date-Manip-6.58/lib/Date/Manip/Changes5to6.pod#TIME_ZONE_SUPPORT.

Personally I use DateTime for all date ... er, manipulation. (Note that you should let it handle Daylight Savings Time automatically for you, i.e. don't specify CST but rather "America/Chicago" or similar.)

$ perl -MDateTime -E '
my $dt = DateTime->now;
say join " ", $dt, $dt->time_zone_short_name;
$dt->set_time_zone("America/Chicago");
say join " ", $dt, $dt->time_zone_short_name;
'

Output:

2017-05-01T16:53:29 UTC
2017-05-01T11:53:29 CDT

Hope this helps!

Update: added DT example

[mangrove]

Thanks for the info as well as the new suggestion code, I will try that.