#MyVars.pm
package MyVars;
use strict;
use warnings;
use Exporter ();
our @ISA = 'Exporter';
our ($one,$two,$three,$four,$five);
our @EXPORT = qw/$one $two $three $four $five call_variables/;

sub call_variables {
  #pick up a string I've passed from previous program via 'spec_vars'
  my $spec_vars = param('spec_vars');
  ($one,$two,$three,$four,$five) = split /~/, $spec_vars;
  return; # nothing; this sub only sets the variables
}
1;


# in your script
use MyVars; # declares variables (actually just aliases them to the ones in the MyVars package)

# to start with, they will be undefined (or at least should be treated as such)
call_variables();
# now you can say
$fred = $one . $two;