> I don't understand why this change should be necessary.
> C strings are NUL-terminated by default, it's not necessary
> to add the \0 explicitly. What problem you exactly
> try to fix?

what i exactly tryied to fix is garbages on "mount -vv".

afaik, snprintb 'new' format needs two NULs at the end.
(one for terminate string to be printed for the bit
and another for terminate format string itsself.)

YAMAMOTO Takashi