anchor.diff:         integer atom1_id,atom2_id
          integer k 
          logical ok
  +       logical osmooth
          double precision f
          integer fn_in
          integer fn_out
  
positive.code:        atom2_tag = " "
         rmax = -1
         nb = -1
  c
  c      ------------------------
  c      allocate io file array
  
negative.code:             atom2_tag = buffer
            end if
            go to 16
         else if(buffer.eq."-smooth") then
            osmooth = .true.
            goto 16
         else if(buffer.eq."-rmax") then
            i = i+1
            call my_get_command_argument(i,buffer,l,istatus)
  