Function nm_client_add_connection2 

pub unsafe extern "C" fn nm_client_add_connection2(
    client: *mut NMClient,
    settings: *mut GVariant,
    flags: NMSettingsAddConnection2Flags,
    args: *mut GVariant,
    ignore_out_result: gboolean,
    cancellable: *mut GCancellable,
    callback: GAsyncReadyCallback,
    user_data: gpointer,
)

Available on crate feature v1_20 only.