170     def _ListDir(self, dir_path, file_type="all"):  argument
193             self._shell, dir_path, "*", find_option)) - set([dir_path])
201     def _TraverseRootDir(self, dir_path="/"):  argument
204         dirs = [dir_path]
205         for d in self._ListDir(dir_path, "dir"):
214         for dir_path in self._dirs_to_check:
215             current_dirs = self._ListDir(dir_path, "dir")
228         def _CheckSymlinks(dir_path):  argument
230             current_symlinks = self._ListDir(dir_path, "symlink")
245         for dir_path in self._dirs_to_check:
246             _CheckSymlinks(dir_path)
259         def _CheckFiles(dir_path):  argument
261             current_files = self._ListDir(dir_path, "file")
281         for dir_path in self._dirs_to_check:
282             _CheckFiles(dir_path)
291         for dir_path in self._dirs_to_check:
292             unknown_files = (self._ListDir(dir_path) -
293                              self._ListDir(dir_path, "dir") -
294                              self._ListDir(dir_path, "symlink") -
295                              self._ListDir(dir_path, "file"))