Try to scan some existing directory_path which is supposed to be a correctly spelled
After this call the client is supposed to check last_scan_status to
know. So, when last_scan_status is True after this call, the entire directory has been
read. Also note that the given directory_path is always left unchanged, but in case of
a successful last_scan_status, the path attribute usually contains an absolute
equivalent of the directory_path.
See also scan_with, scan_subdirectory, scan_current_working_directory.