pub unsafe extern "C" fn g_file_copy_async(
source: *mut GFile,
destination: *mut GFile,
flags: GFileCopyFlags,
io_priority: c_int,
cancellable: *mut GCancellable,
progress_callback: GFileProgressCallback,
progress_callback_data: gpointer,
callback: GAsyncReadyCallback,
user_data: gpointer,
)