drop ole and use File::Find::Rule (a fine module, and platform independent!)

#!/usr/bin/perl
use strict;
use warnings;

use File::Find::Rule ();


die 'usage: dir_size.pl *directory*' 
    unless 1 == @ARGV;

my( $size, $files, $folders );

my $rule= File::Find::Rule->start( @ARGV );
while( my $item= $rule->match )
{
    next if $ARGV[0] eq $item;
    $size+= -s $item;
    -f $item and $files++;
    -d $item and $folders++;
}
printf "Size: %fMb (%d byte), Files: %d, folders: %d\n"
    => $size / 1024**2, $size, $files, $folders;
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~Particle *accelerates*