the GAsyncResult passed to your GAsyncReadyCallback
the number of bytes of disk space used
the number of directories encountered
the number of non-directories encountered
TRUE if successful, with the out parameters set. FALSE otherwise, with error set.
GException on failure.
2.38
Collects the results from an earlier call to g_file_measure_disk_usage_async(). See g_file_measure_disk_usage() for more information.