Linux内核常用API字符设备驱动(虚拟串口)是什么呀？

character driver：

MKDEV(VSER_MAJOR,VSER_MINOR)
int register_chrdev_region(dev_t from, unsigned count, const char *name)
int alloc_chrdev_region(dev_t *dev, unsigned basemior, unsigned count, const char *name)
unregister_chrdev_region(dev_t *dev, unsigned count)
void cdev_init(struct cdev *dev, const struct file_operations *fops)
void cdev_del(struct cdev *p)
struct cdev *cdev_alloc(void)
int (*open)(struct inode *, struct file *)//可被多次打开
int (*release)(struct inode *, struct file *)//全部关闭后执行