while ( $line = <FH> ) { 
  # do stuff to $line
}
##</code><code>##

#!/usr/bin/perl

use strict;
use warnings;

my @three;

# Stoke it
chomp ($three[0] = <DATA>);
chomp ($three[1] = <DATA>);

while(<DATA>) {
  chomp ($three[2] = $_);

  # Do stuff to process @three
  print join ("\t", @three), "\n";

  # Rotate
  shift(@three);
}

__DATA__
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