How much memory do you have at your disposal? 
my @input = <STDIN>;
my $i = $#input;
while ($i >= 0) {
  print $input[$i--];
}

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Note that if you want to use less memory, you could split the file into chunks, reverse the chunks and then reverse-concatenate the chunks.

"What should it profit a man, if he should win a flame war, yet lose his cool?"

In reply to Re: Reversing A File by Joost
in thread Reversing A File by camelcom

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