private function parseResponse()
	{
		if(($line=fgets($this->_socket))===false)
			throw new CException('Failed reading data from redis connection socket.');
		$type=$line[0];
		$line=substr($line,1,-2);
		switch($type)
		{
			case '+': // Status reply
				return true;
			case '-': // Error reply
				throw new CException('Redis error: '.$line);
			case ':': // Integer reply
				// no cast to int as it is in the range of a signed 64 bit integer
				return $line;
			case '$': // Bulk replies
				if($line=='-1')
					return null;
				$length=$line+2;
				$data='';
				while($length>0)
				{
					if(($block=fread($this->_socket,$length))===false)
						throw new CException('Failed reading data from redis connection socket.');
					$data.=$block;
					$length-=$this->byteLength($block);
				}
				return substr($data,0,-2);
			case '*': // Multi-bulk replies
				$count=(int)$line;
				$data=array();
				for($i=0;$i<$count;$i++)
					$data[]=$this->parseResponse();
				return $data;
			default:
				throw new CException('Unable to parse data received from redis.');
		}
	}