设计目的：通过设计和调试一个简单的文件系统，主要是模拟文件操作命令的执行，来模拟文件管理，使学生对主要文件操作命令的实质和执行过程有比较深入的了解，掌握它们的基本实施方法。

设计要求：

⑴设计一个支持n个用户的文件系统，每个用户可拥有多个文件；

⑵采用二级或二级以上的多级文件目录管理；

⑶对文件应设置存取控制保护方式，如“只能执行”、“允许读”、“允许写”等；

⑷系统的外部特征应接近于真实系统，可设置下述文件操作命令：建立文件、打开文件、关闭文件、删除文件、读文件、写文件、复制文件、查询目录。

⑸通过键盘（或鼠标）使用该文件系统，系统应显示操作命令的执行结果。

-Design Objective: To design and debug a simple file system, mainly the implementation of the simulation file manipulation commands, to simulate the file manager, so that students have a more in-depth understanding of the substance and the implementation process of the main file manipulation commands to master their basic implementationapproach.

Design requirements:

The ⑴ design a file system supports n users, each user can have multiple files

⑵ two multi-level or two above the file directory management

(3) the file should be set up access control to protect only the implementation, "allowed to read," Allow Write "

⑷ the external characteristics of the system should be close to the real system, file manipulation commands can be set to the following: creating a document, open the file, close the file, delete files, read files, write files, copy files, query the directory.

⑸ use the file system via the keyboard (or mouse), the system should display the results of the implementati