This snippet executes du in the current directory and parses the output into a hash. For example, if du produces this:

96      ./m4
6280    ./po
368     ./intl
1968    ./doc
512     ./contrib
32      ./charmaps
440     ./imap
14896   .
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then my snippet will produce a %dirs hash that looks like this:

(
  '.' => {
    'blocks' => 14896,
    'dirs' => {
      'imap' => {
        'blocks' => 440
      },
      'm4' => {
        'blocks' => 96
      },
      'charmaps' => {
        'blocks' => 32
      },
      'po' => {
        'blocks' => 6280
      },
      'contrib' => {
        'blocks' => 512
      },
      'doc' => {
        'blocks' => 1968
      },
      'intl' => {
        'blocks' => 368
      }
    }
  }
)
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open DU, 'du .|' or die "Couldn't open du: $!";
while (<DU>) {
  ($blocks, $_) = split;
  s:/:'}{dirs}{':g;
  eval "\$dirs{'$_'}{blocks} = $blocks"
}
close DU;
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