public function appendFile($sourceFilePath)
    {
        // open the new uploaded chunk
        if (!$in = @fopen($sourceFilePath, 'rb')) {
            @fclose($this->destinationFile);
            throw new ChunkSaveException('Failed to open input stream', 101);
        }

        // read and write in buffs
        while ($buff = fread($in, 4096)) {
            fwrite($this->destinationFile, $buff);
        }

        @fclose($in);

        return $this;
    }