As of now the only possible way to achieve this is setting the activation mode to email in Admijnistration > Authentication > Authentication Options >Account Activation Mode
This feature will email the user with his password .
According the thread below this will be available in version 12
This could likely not be accomplished just with script, though plugins could help. A current solution could be to use external authentication instead, using one of the built-in authentication provider plugins or a custom plugin.
