注册字符驱动。但是不自动挂载。
lsmod charDevice.ko
mknod /dev/charDevice3 c 200 0
cat /dev/charDevice
![img.png](img.png)
Linux has always enforced device file identification by a unique identifier, composed of
two parts, a major and a minor.

enforce 强制
identification 标识
a unique identifier 一种唯一标识符
composed of two parts 由两个部分组成
a major and a minor 主设备号和次设备号~~~~
这个是个整形数，由主次设备号组成
the preceding excerpt 前面的摘录
excerpt 摘录 英 / ˈeksɜːpt


Character device data structure introduction
字符设备数据结构体介绍
struct cdev {
    struct kobject kobj;
    struct module *owner;
    const struct file_operations *ops;
    dev_t dev;
    [...]
};

include/linux/kdev_t.h
![img.png](img.png)