I also have a similar situation where I have many such constants (e.g., port numbers, database parameters, directory names) that are used by several modules and scripts. I usually create a module called Constants.pm, which contains all the constants: 
# Constants.pm
package Constants;

use strict;
use Exporter;
our @ISA = qw(Exporter);
# if you want to automatically import
our @EXPORT = qw(%ABC $A);
# or if you want to explicitly import
our @EXPORT_OK = ();

our $A = "A";
our %ABC = ("A"=>1,"B"=>2,"C"=>3);
1;

[download]
You can then just "use Constants" in other modules and scripts.

In reply to Re: Usage of global variables by johnnywang
in thread Usage of global variables by Anonymous Monk

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