How to ensure MySQL replication SLAVE is fully synchronized with the replication MASTER?

Using simple replication settings with one MASTER and one SLAVE, how can one ensure that the SLAVE and MASTER are fully synchronized?

Now yes, they both started from the exact same image and replication is working and reporting that everything is okay BUT: * It has happened that there were errors stopping the replication and then the replication had to be stopped and later resumed. * Perhaps a change accidentally occurred on the SLAVE and then it's not the same as the MASTER anymore. * Other whichever scenarios that might break sync.

While it's possible to do a big mysqldump of both database and compare the files I would be interested in a method that can be implemented more easily and also can be checked automatically to ensure all is in sync.

Thanks