anchor.diff:             napx, xv1, xv2, yv1, yv2, sigmv, ejv, naa, nzz, nucm, nqq, pdgid, &
              spin_x, spin_y, spin_z )
   
  -      if (ret.eq.-1) then
  -         write(lerr,'(A)')'FLUKA> ERROR -1 in Fluka communication returned by fluka_send...'
  -         write(fluka_log_unit,'(A)')'# Error -1 in Fluka communication returned by fluka_send...'
  +      if (ret.lt.0) then
  +         write(lerr,'(A,i4,A)')'FLUKA> ERROR ', ret,' in Fluka communication returned by fluka_send...'
  +         write(fluka_log_unit,'(A,i4,A)')'# Error ', ret, ' in Fluka communication returned by fluka_send...'
            call prror
         end if
   
  
positive.code:               flm, flet, flt, &
                flpdgid, flq, flsx, flsy, flsz)
  
        if(n.eq.-1) then
          write(fluka_log_unit,*) "# FlukaIO error: Server timed out while waiting for message"
          fluka_cid = -1
          fluka_receive = -1
          return
  
negative.code:     n = ntsendeob(fluka_cid)
  
      if(n.lt.0) then
        write(fluka_log_unit,*) "# FlukaIO error: ", n, " - Error sending End of Batch"
        fluka_cid = -1
        fluka_send = -1
        return
  