请帮我写个C语言程序。要求使用librdkafka获取专题testk。获取的数据立刻调用eCAL向局域网内组播。

好的，以下是一个使用librdkafka获取专题testk并使用eCAL向局域网内组播的C语言程序示例：

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <librdkafka/rdkafka.h>
#include <ecal/ecal.h>

#define ECAL_TOPIC "test_topic"
#define ECAL_PORT 60000

static void msg_consume(rd_kafka_message_t *rkmessage, void *opaque) {
    if (rkmessage->err) {
        fprintf(stderr, "Error consuming message: %s\n", rd_kafka_message_errstr(rkmessage));
        return;
    }

    // Send message to eCAL
    eCAL::Initialize(ECAL_PORT, "kafka_consumer");
    eCAL::CPublisher pub(ECAL_TOPIC);
    pub.Send(rkmessage->payload, rkmessage->len);
    eCAL::Finalize();

    rd_kafka_message_destroy(rkmessage);
}

int main(int argc, char **argv) {
    char errstr[512];
    rd_kafka_t *rk;
    rd_kafka_conf_t *conf;
    rd_kafka_topic_t *rkt;
    rd_kafka_resp_err_t err;
    char *brokers = "localhost:9092";
    char *topic = "testk";
    int partition = RD_KAFKA_PARTITION_UA;
    int64_t start_offset = RD_KAFKA_OFFSET_BEGINNING;

    // Kafka configuration
    conf = rd_kafka_conf_new();
    if (rd_kafka_conf_set(conf, "bootstrap.servers", brokers, errstr, sizeof(errstr)) != RD_KAFKA_CONF_OK) {
        fprintf(stderr, "Error setting Kafka configuration: %s\n", errstr);
        return 1;
    }

    // Kafka consumer
    rk = rd_kafka_new(RD_KAFKA_CONSUMER, conf, errstr, sizeof(errstr));
    if (!rk) {
        fprintf(stderr, "Error creating Kafka consumer: %s\n", errstr);
        return 1;
    }

    // Kafka topic
    rkt = rd_kafka_topic_new(rk, topic, NULL);
    if (!rkt) {
        fprintf(stderr, "Error creating Kafka topic: %s\n", rd_kafka_err2str(rd_kafka_last_error()));
        rd_kafka_destroy(rk);
        return 1;
    }

    // Start consuming messages
    if (rd_kafka_consume_start(rkt, partition, start_offset) == -1) {
        fprintf(stderr, "Error starting Kafka consumer: %s\n", rd_kafka_err2str(rd_kafka_last_error()));
        rd_kafka_topic_destroy(rkt);
        rd_kafka_destroy(rk);
        return 1;
    }

    // Consume messages
    while (1) {
        rd_kafka_message_t *rkmessage = rd_kafka_consume(rkt, partition, 1000);
        if (!rkmessage) {
            continue;
        }

        msg_consume(rkmessage, NULL);
    }

    // Stop consuming messages
    rd_kafka_consume_stop(rkt, partition);
    rd_kafka_topic_destroy(rkt);
    rd_kafka_destroy(rk);

    return 0;
}

这个程序使用librdkafka获取专题testk的数据，并使用eCAL向局域网内组播。你可以根据自己的需要修改程序中的一些参数，比如Kafka的brokers地址、topic名称、eCAL的端口号等。