/* Handle multiple occurrences. */
   n = 1;
   do forever;
      k = index(s, t, n);
      if k = 0 then
         do;
            if n = 1 then put skip list (t, ' is nowhere in sight');
            stop;
         end;
      else if k = 1 then
         put skip edit ('<', t, '> starts at the beginning of  ', s) (a);
      else if k+length(t)-1 = length(s) then
         put skip edit ('<', t, '> is at the end of  ', s) (a);
      else put skip edit ('<', t, '> is within  ', s) (a);
      n =   k + length(t);

      if k > 0 then
         put skip edit ('<', t, '> starts at position ', trim(k)) (a);
      else stop;
   end;