The nodes in this thread have focused on using regexes and substr to parse a directory path. IMHO, it might be a better idea to use a module called File::Spec, which is specifically designed for this, and works across a few different platforms, which is a nice bonus.

Here's an example script using this module to produce the output you're looking for:

#!/usr/bin/perl -wT

use strict;
use File::Spec;
use Data::Dumper qw(Dumper);

use constant PATH => '/One/Two/Three';

#split up the path into directory segments
my @dirs = File::Spec->splitdir(PATH);

my @paths;

while(my $path = File::Spec->catfile(@dirs)) {
  push @paths, $path;
  pop @dirs;
}

print Dumper(\@paths);
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which prints out:

$VAR1 = [
          '/One/Two/Three',
          '/One/Two',
          '/One'
        ];
[download]