Thanks to everyone. Japhy, I used your example:

@info = function to read input ;

for (sort third_field @info) {  
  print "Record: $_";
}

sub third_field {
  my $x = (split ' ', $a)[2];
  my $y = (split ' ', $b)[2];
  $y <=> $x;
}
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I tried a sample similar to that but I had

$a0 = $a -> [2]
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instead of

$x = (split ' ', $a)[2];
[download]

Thanks!!!