open(fd1,"log.txt") or die"unable to open";
open(fd2,">>log2.txt");
while($getVal=<fd1>)
{
  
  if($getVal=~/name/)
  {
   $getVal="Designation :Manager\n".$getVal;   
  }
  print fd2 $getVal;
}

close(fd1);
close(fd2);
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Edited by planetscape - added code tags