use Cwd qw( realpath );
$script_fqn = realpath($0);

##</code><code>##

use File::Basename qw( basename );
$script_fn = basename($0);

##</code><code>##

use Cwd            qw( realpath );
use File::Basename qw( dirname );
$script_dir_fqn = dirname(realpath($0));