Some useful material.
Factory pattern is a basic pattern in grant software framework.
We create object, parent, with common interface to create new type of object.
The common interface is a static member-function (static factory method) which creates & returns instances, hiding the details of children.
The following will show a snappiest code of Android Q.
I refer an article KD-Project_2: kernel module sk_buff send packet and make a test.
I surf the internet and see a good article, and I back up a part of the article.
How does network device driver works