说明：   首先分配一定容量的磁盘存储空间，作为文件存储空间；  建立相应的文件系统，使用FAT文件系统；  为该文件系统设计相应的数据结构来管理目录、磁盘空闲空间、已分配空间等。  提供文件的创建、删除、移位、改名等功能。  提供良好的界面，可以显示磁盘文件系统的状态和空间的使用情况；  提供虚拟磁盘转储功能，可将信息存入磁盘，还可从磁盘读入内存；
( first allocates a certain amount of disk storage space, as the file storage space  establish the appropriate file system, use the FAT file system  File System Design for the corresponding data structure to manage directories, disk free space, allocated space.  provides file creation, deletion, shift, renamed functions.  provide a good interface, you can display the status of the file system and disk space usage  provides a virtual disk dump function, the information can be saved to disk, but also read from disk into memory )