Is a multiple INSERT atomic?

[medi !]

Hi folks,

is an INSERT like this one:
INSERT INTO tbl_name (a,b,c) VALUES(1,2,3),(4,5,6),(7,8,9);
atomic?

Or in other words. Is it guaranteed that the AUTO_INCREMENT values are sequentially?
e.g. 1,2,3 and not 1,2,4
Or should I use LOCK/UNLOCK TABLES?

I found nothing about this in the documentation.

ty
medi