$r->headers_out->set('Accept-Ranges' => 'bytes');
  my $range_request = $r->set_byterange; 

  unless ((my $status = $r->meets_conditions) == OK) {
    return $status;
  }

  if ($range_request) {
   while( my($offset, $length) = $r->each_byterange) 
   { 
       seek $fh, $offset, 0;
      $r->send_fd($fh, $length); #TO DO: migrate to mod2
   }