Try to scan some existing directory_path which is supposed to be a correctly spelled
directory path.
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.
Try to scan Current using some_path where some_path can be either a file path or
an existing directory path.
When some_path is a directory path, the behavior is equivalent to scan.
When some_path is the path of an existing file, the directory which contains this
file is scanned.