Wraps [method@Gio.
File.append_to_async] as a [class@Dex.Future].
| file |
a [iface@Gio.File] |
| flags |
flags for appending to the file |
| io_priority |
priority for the IO operation |
|
a [class@Dex.Future] that resolves to a [class@Gio.FileOutputStream] or rejects with error. |