#5876 broken pipe handling

        # how to reproduce bug
        # first set up redis timeout to 5 seconds in /etc/redis/redis.conf as described in http://redis.io/topics/clients
        $redisConfig = [
            'hostname' => 'localhost',
            'port' => 6379,
            'connectionTimeout' => 5,
        ];
        $redis = new \yii\redis\Connection($redisConfig);
        $redis->executeCommand('PING');

        sleep(20);

        try {
            // this is will cause yii\db\Exception in Connection::parseResponse since Redis dropped connection
            $redis->executeCommand('PING');
        }
        catch (\Exception $e) {
            // now Connection::close will try to send QUIT command but got yii\base\ErrorException
            // in Connection::executeCommand on fwrite
            // So we can't send any command and can't close connection
            $redis->close();
        }