$ rmdir --help
Usage: rmdir [OPTION]... DIRECTORY...
Remove the DIRECTORY(ies), if they are empty.
--ignore-fail-on-non-empty
ignore each failure that is solely because a directory
is non-empty
-p, --parents remove DIRECTORY and its ancestors; e.g., 'rmdir -p a/b/c' is
similar to 'rmdir a/b/c a/b a'
-v, --verbose output a diagnostic for every directory processed
--help display this help and exit
--version output version information and exit
GNU coreutils online help: <http://www.gnu.org/software/coreutils/>
Full documentation at: <http://www.gnu.org/software/coreutils/rmdir>
or available locally via: info '(coreutils) rmdir invocation'