f
e
d
c
b
a

##</code><code>##

use warnings;
use strict;

use File::ReadBackwards;

my $file = 'test.txt';

my $fh = File::ReadBackwards->new($file) 
  or die "can't read the damned '$file' file!: $!";
 
until ($fh->eof) {
    print $fh->readline;
}

##</code><code>##

a
b
c
d
e
f