# Traverse directories recursively using opendir()
# It's as fast as you can get (I think)

use strict;
use warnings;
use Time::HiRes;

my $base_dir = "/";
my @directories;
my $file_count = 0;

chdir $base_dir;

while($base_dir) {
    my @dir_contents = get_listing($base_dir);
    for my $sub_file (@dir_contents) {
        if(-d "$base_dir$sub_file" && $sub_file!~/^\.{1,2}$/) {
            push(@directories, "$base_dir$sub_file/");
        }elsif(-f "$base_dir$sub_file") {
            $file_count++;
        }
        print "$base_dir$sub_file\n";
    }
    $base_dir = shift(@directories);
}

my $elapsed_time = (Time::HiRes::time-$^T);
print "Completed listing in: $elapsed_time seconds\n";
print "Total files: $file_count\n";

sub get_listing {
    my $dir = $_[0];
    my @dir_contents;
    opendir(DIR, $dir);
        @dir_contents = readdir(DIR);
    closedir(DIR);
    return @dir_contents;
}