Does each element have a line to itself or is the data multiline? As in, if we read line say 123 from file A, will line 123 in file B be the correct line to do the processing with?

If that is the case, then you could just read both files a line at a time, and use a simple regex to get the value out of the <elem> wrapper;


my ($a,$b,$value_a,$value_b);

while (1) {
  $a = <A>;
  $b = <B>;
 
  if ($a =~ m/<elem>(.*?)</elem>/)
    {
     $value_a = $1;
    }

   if ($b =~ m/<elem>(.*?)</elem>/)
     {
      $value_b = $1;
     }   

  last if !defined $value_a || !defined $value_b;
  print data_transform($value_a, $value_b);
}

[download]

I'm sure better perl adepts than me could write it better/faster, but I think that would work if the files have a line for line concurrency.

In reply to Re: Processing Two XML Files in Parallel by Logicus
in thread Processing Two XML Files in Parallel by tedv

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