Sys::Info::OS will detect bitness. In conjunction with Sys::Info::Base: 
package Foo;

use strict;
use warnings;
use base qw(Sys::Info::Base);

my $class = __PACKAGE__->load_subclass('Sys::Info::Driver::%s::OS');
print $class, "\n";
print $class->bitness, "\n";

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In reply to Re: How to know the Windows OS that perl is running on by Khen1950fx
in thread How to know the Windows OS that perl is running on by alain_desilets

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