rmdir - delete a directory
int rmdir(const char *pathname);
rmdir deletes a directory, which must be empty.
On success, zero is returned. On error, -1 is returned,
and errno is set appropriately.
EPERM The filesystem containing pathname does not support
the removal of directories.
EFAULT pathname points outside your accessible address
EACCES Write access to the directory containing pathname
was not allowed for the process's effective uid, or
one of the directories in pathname did not allow
search (execute) permission.
EPERM The directory containing pathname has the sticky-
bit (S_ISVTX) set and the process's effective uid
is neither the uid of the file to be deleted nor
that of the directory containing it.
pathname was too long.
ENOENT A directory component in pathname does not exist or
is a dangling symbolic link.
pathname, or a component used as a directory in
pathname, is not, in fact, a directory.
pathname contains entries other than . and .. .
EBUSY pathname is the current working directory or root
directory of some process.
ENOMEM Insufficient kernel memory was available.
EROFS pathname refers to a file on a read-only filesys
SVr4, SVID, POSIX, BSD 4.3
Infelicities in the protocol underlying NFS can cause the
unexpected disappearance of directories which are still
rename(2), mkdir(2), chdir(2), unlink(2), rmdir(1), rm(1)