Listen to a folder and modify incoming files on change

I want to convert pcap files to json files using shell script (and tshark). As soon as one or more new pcap files are copied into a folder, the command tshark should be executed and the resulting json data should be stored in another file (in a different order). As soon as the conversion is finished the pacap file should be deleted. The idea looks something like that: while(true){ wait_for_IN_folder_changed tshark -T ek -x -r \in\in.pcap > \out\out.json rm \in\in.pcap } It would be best to start the tshark process multithreaded to increase the parallelism and thus the throughput. But would different threads probably get in each other's way here?