Example of rw lock
-rw-r--r-- 457 .gitignore
-rw-r--r-- 1074 LICENSE
-rw-r--r-- 77 README.md
drwxr-xr-x - echo
drwxr-xr-x - echo_config
drwxr-xr-x - hello
drwxr-xr-x - race
drwxr-xr-x - race_config
drwxr-xr-x - race_rw
drwxr-xr-x - sysctl