摘要
根据硬盘主引导记录的自举特点，将特定代码写入主引导扇区，这样，主引导程序自举时，由特定代码将中断21H重新指定，由此接管了DOS3BH号功能调用，规范了DOS内核的工作进程，实现了目录文件使用的限制，从而达到了保护其它目录下文件的目的。
According to the bootstrap characteristic of the main boot record of hard disk, the specific codes are twritten into the majn botstrap aector. When the main boot program bootstraps, the codes will reassign interrupt 21 H, and the progam will take over the functions of DOS 3BH. Thus, the working process of DOS Kernerl is normalized Limited usage of files in this directory is realized and files in other directories are protected.
