On an ufs partition, rmdir(1) removes only empty directories. If one uses it on a hammer filesystem, it is also able to delete regular files:
Ufs example: $ touch one two $ mkdir three $ rmdir one two three rmdir: one: Not a directory rmdir: two: Not a directory $ ls one two three ls: three: No such file or directory one two Hammer example: $ touch one two $ mkdir three $ rmdir one two three $ ls one two three ls: one: No such file or directory ls: three: No such file or directory ls: two: No such file or directory -- Francois Tigeot
