1. Please use <code> around your code blocks. *grin*
2. Glob calls the shell to do its expansion. Thus you will not get a cross platform way of searching for files with it. command.com's "all files" is *.* In unix, that would mean getting all the files with a . in their name which could be less than the total number of files.

use strict;
my $directory = '.';
print "\n\n";
print CountSize($directory);
print "\n\n";
sub CountSize {
 my $directory = shift;
 $directory .= "/*";
 my ($ask, $filesize,$item, $size, @raiz);
 @raiz = glob($directory);
 foreach $item (@raiz) {
   $ask = -d $item;
   if ($ask) {
     $size += &CountSize($item);
   } else {
     $size += -s $item;
   }
 }
 return($size);
}
[download]

use strict;
my $dir = '.';
print &dir_tree_size($dir) . "\n";
exit 0;

sub dir_tree_size {
  my $dir = shift;
  my ($i,$total);
  $total = 0;
  opendir DIR, $dir;
  my @files = grep !/^\.\.?$/, readdir DIR;
  for $i (@files) {
    if(-d $i) { $total += dir_tree_size($dir . "/$i") }
    else { $total += -s $i}
  }
  return $total;
}
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