flags affecting the unmount if required for stopping.
a GMountOperation or NULL to avoid user interaction. [allow-none]
optional GCancellable object, NULL to ignore. [allow-none]
a GAsyncReadyCallback, or NULL. [allow-none]
user data to pass to callback
Asynchronously stops a drive. When the operation is finished, callback will be called. You can then call g_drive_stop_finish() to obtain the result of the operation. Since 2.22