title: Compare files with DFSORT , insert a string 'ADD' in front of new records
body: <p>I have 2 work files old(F1) and new (F2), both of the same length. I should compare both the files record by record and for any new records in the new (F2) work file , I should insert 'ADD' in front of it in starting 3 positions and for rest of the records(matched) it should be spaces.</p>
  
  <p>As of now I am able to copy the records which are in F2 but not in F1 using the below code:</p>
  
  <pre><code>//SYSIN DD *
   JOINKEYS FILE=F1,FIELDS=(1,79,A)
   JOINKEYS FILE=F2,FIELDS=(1,79,A)
   JOIN UNPAIRED,F2,ONLY
   SORT FIELDS=COPY
  /*
  </code></pre>
  
  <p>but I need all the records from F2 with 'NEW' string in front of new records, can this be done in single step? </p>