CArchiver::_readBlock

private function _readBlock()
{
	$v_block = "";
	if (is_resource($this->_dFile))
	{
		if ($this->_bCompress)
		{
			$v_block = @gzread($this->_dFile, 512);
		}
		else
		{
			$v_block = @fread($this->_dFile, 512);
		}
	}
	return $v_block;
}