[Samba] How to exit samba gracefully from within the smbd code

[Shirish Pargaonkar]

What is the best way for smbd to shutdown for whatever reason?

For example, I want samba to shutdown whenever it receives a trans2
setfsinfo  smb/cifs command with say an invalid info level, instead of
returning an error.

Not sure whether putting exit call in default case would suffice, because I
did so and smbd was still running.

Regards,

Shirish