#!/usr/bin/perl -w

use strict;
use CGI qw/:standard/;
$|=1;

my $columns = param('c') || 4;

opendir(DIR, ".") || die "cannot open dir: $!";
foreach (sort readdir(DIR)) {
    next if /~\z/ || $_ eq "ls.cgi" || $_ eq "." || $_ eq "..";
    push @{ (-d) ? $_[0] : $_[1] },
        (-d) ? b(a({href=>"$_"},"[ $_ ]")) : a({href=>"$_"},"$_");
}
closedir DIR;

# Combine dirs and files
$_[3] = [ @{$_[0]}, @{$_[1]} ];

print
    header,
    start_html('Directory Listing'),
    h3('Directory Listing'),
    b("Dir Count: ".@{$_[0]}), b(", File Count: ".@{$_[1]}),
    table({-border=>0,-cellpadding=>5,-cellspacing=>5},
      map Tr($_),
      grep { length($_) > 0 }
      map td([ splice @{$_[3]},0,$columns ]), @{$_[3]}
     ),
    end_html;

__END__
[download]

Most notably I've taken another look at Aristotle's code and replaced the cute splice with array refs which turns out to be useful in the output section. E.g. I've added a directory count and a file count.

The other noticable part is that I've removed the 0 .. (@_ / $columns) and inserted a grep to eliminate extra list elements that cause extra TR elements (the initial reason I put that in there in the first place).

And, yes, I cleaned up the exclusion logic to use eq, etc.

Enjoy!

Update: Yes, the grep is a hack, for a full treatize on this issue click here.