Your sub is OK. For me it returns 7200 - GMT+2.

For calculating time delta you could take a look at Date::Calc and/or DateTime.

Update:

Perhaps calculating the time delta from the timestamps in your file(s), not from the current time? Or do i miss something?

Update2:

I'm still struggling a bit with this.

As far as i understood your timezone is GMT.

You have a file with some timestamps you think they are in another timezone, right?

And you want to know the difference between this timestamps and GMT, right?

So IMHO your sub needs the timestamps from your file as params...

Update3:

«why are timegm and timelocal returning the same epoch seconds values»

Because your box is GMT?

Update4:

Just as a little addendum (assuming you are using bash):

Karls-Mac-mini:monks karl$ date
Di 14 Mai 2013 23:22:21 CEST
Karls-Mac-mini:monks karl$ export TZ=UTC
Karls-Mac-mini:monks karl$ date
Di 14 Mai 2013 21:22:47 UTC
Karls-Mac-mini:monks karl$ unset TZ
Karls-Mac-mini:monks karl$ date
Di 14 Mai 2013 23:23:11 CEST

[download]

Update5:

OK, this is the last one, i promise...


#!/usr/bin/env perl 
# delta.pl
use strict;
use warnings                                                          
+                 

use Time::Local; 

print getGMDelta() . qq(\n);

sub getGMDelta
{
    ($sec,$min,$hour,$mday,$mon,$year,$wday,$yday,$isdst) =
        localtime(time);
    $ltime = timelocal($sec,$min,$hour,$mday,$mon,$year);
    $gtime = timegm($sec,$min,$hour,$mday,$mon,$year);
    $rv = $gtime - $ltime;
    return($rv);
}

__END__

Karls-Mac-mini:monks karl$ export TZ=UTC
Karls-Mac-mini:monks karl$ ./delta.pl
0
Karls-Mac-mini:monks karl$ unset TZ
Karls-Mac-mini:monks karl$ ./delta.pl
7200

[download]

Please see also:

Regards, Karl

«The Crux of the Biscuit is the Apostrophe»

In reply to Re: why are timegm and timelocal returning the same epoch seconds values by karlgoethebier
in thread why are timegm and timelocal returning the same epoch seconds values by kehansen

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