What the rest said! In the Airbus you may want to know that you are in ALT* because there could be a mode reversion to V/S until ALT is annunciated.
Tip: if you are not happy with the ALT* calculated capture of your altitude (entering ALT with changing dynamics, i.e. large +- speed trend and/or speedbrake retraction/extension, Engine fail, reduction to CLB thrust from TOGA/high flex subsequent to ALT* engagement) you can force an ALT* recomputation by pulling the ALT selector once again. This will recompute a new capture using a new snapshot of your aircraft state/energy, this could avoid unwanted speed excursions as a consequence of a a too steep/shallow capture geometry.