while(my @ready = $select->can_read) {
...
      my $data;
      my $length = sysread $fh, $data, 4096;

...
           $processeddata .= $data;
...
}

##</code><code>##

      if( ! defined $length || $length == 0 ) {
        $err .= "Error from child: $!\n" unless defined $length;
        $select->remove($fh);
      }