Hey @kaf,
Thanks for reaching out to the Cloudera community.
You can use "tail" command and then pipeline it to Kafka console producer if you want to read the whole file and then continue tailing for subsequently appended lines.
$ tail -f -n +1 <filename> | kafka-console-producer --broker-list <Broker_Host>:9092 --topic <topic_name>
Let me know if this helps.