# Untested code - use at your own risk
  sub handledirectory {
    my ($directory) = @_;
    my ($entry, @direntries);
    opendir( DIR, $directory ) or die "Canīt read $directory : $!\n";
    @direntries = readdir( DIR ) or die "Error reading $directory : $!\n";
    closedir DIR;

    foreach $entry, @direntries {
      # File::Spec gives us cross-platform path utilities
      # and comes with every Perl standard distribution
      require File::Spec;
      my $fullpath;
      
      # skip current and parent directory entries
      next if $entry =~ /^\.\.?$/;

      $fullpath = File::Spec->catfile( $directory, $entry );
      if (-d $fullpath ) {
        &handledirectory($fullpath);
      } elsif ( -f $fullpath ) {
        # This second call to stat() (implicit in the "-f")
        # could be done away by using some other short
        # variable that does caching, but that would maybe
        # confuse the readers ...
        ... do stuff ...
      } else {
        # something strange ...
      };
  }