odroid ~ # cd /tmp
odroid /tmp # ls
odroid /tmp # mkdir -p bb/cc/dd
odroid /tmp # touch bb/cc/dd/files
odroid /tmp # touch bb/cc/files
odroid /tmp # tar cvzf a.tgz -C bb/cc
tar: Cowardly refusing to create an empty archive
Try 'tar --help' or 'tar --usage' for more information.
odroid /tmp # tar czvf a.tgz -C bb/cc .
./
./files
./dd/
./dd/files