0                  Successful completion.
    -1                 Indicates an error. errno is set to one of the
                       following:
                       o  EACCES - Search permission is denied for a
                          component of the path prefix.
                       o  EIO - An I/O error occurred while reading
                          the device.
                       o  EINTR - A signal was intercepted during
                          execution of the function.
                       o  EOVERFLOW - One of the values to be
                          returned cannot be represented correctly
                          in the structure pointed to by buffer.
                       o  ENAMETOOLONG - The length of a component
                          of the path parameter exceeds NAME_MAX, or
                          the length of the path parameter exceeds
                          PATH_MAX.
                       o  ENOENT - A component of path does not
                          name an existing file, or path is an empty
                          string.
                       o  ENOTDIR - A component of the path prefix of
                          the path parameter is not a directory.