#!/usr/bin/perl -w
# example for files with max line lengths < 400, but it's adjustable 
# usage tailz  filename  numberoflines 
use strict;

die "Usage: $0 file numlines\n" unless @ARGV == 2;
my ($filename, $numlines) = @ARGV;

my $chunk = 400 * $numlines; #assume a <= 400 char line(generous) 

# Open the file in read mode 
open FILE, "<$filename" or die "Couldn't open $filename: $!";
my $filesize = -s FILE;
if($chunk >= $filesize){$chunk = $filesize}
seek FILE,-$chunk,2; #get last chunk of bytes 

my @tail = <FILE>;
if($numlines >= $#tail +1){$numlines = $#tail +1}
splice @tail, 0, @tail - $numlines;

print "@tail\n";
exit;