Function nm_client_checkpoint_adjust_rollback_timeout 

pub unsafe extern "C" fn nm_client_checkpoint_adjust_rollback_timeout(
    client: *mut NMClient,
    checkpoint_path: *const c_char,
    add_timeout: u32,
    cancellable: *mut GCancellable,
    callback: GAsyncReadyCallback,
    user_data: gpointer,
)

Available on crate feature v1_12 only.