如何在librdkafka中设置复制因子？

#include <librdkafka/rdkafka.h>

int main() {
    rd_kafka_t *rk;
    rd_kafka_conf_t *conf;
    rd_kafka_topic_t *topic;
    char errstr[512];

    // 创建配置对象
    conf = rd_kafka_conf_new();

    // 设置Kafka集群地址
    rd_kafka_conf_set(conf, "bootstrap.servers", "127.0.0.1:9092", errstr, sizeof(errstr));

    // 设置消息确认机制
    rd_kafka_conf_set(conf, "acks", "all", errstr, sizeof(errstr));

    // 设置复制因子
    rd_kafka_conf_set(conf, "replication.factor", "3", errstr, sizeof(errstr));

    // 创建Kafka生产者对象
    rk = rd_kafka_new(RD_KAFKA_PRODUCER, conf, errstr, sizeof(errstr));

    // 创建主题对象
    topic = rd_kafka_topic_new(rk, "my_topic", NULL);

    // 发送消息
    rd_kafka_produce(topic, RD_KAFKA_PARTITION_UA, RD_KAFKA_MSG_F_COPY,
                     "message", sizeof("message"), NULL, 0, NULL);

    // 销毁对象
    rd_kafka_topic_destroy(topic);
    rd_kafka_destroy(rk);

    return 0;
}