用C编写和调试一个文件系统,功能使用命令行的方式实现。模拟文件管理的工作过程。
说明：
1）每个目录项16个字节（在2.2中有具体定义），所以根目录下只允许建立4个子目录或者文件。
2）i-node位图1块64字节，共512位，可以描述512个i-node的使用情况
3）位图的数据结构可以参考“位域”数据结构类型。
4）Data Block区的数据块，是三种类型。包括索引块，文本文件数据块，目录文件数据块。定义时使用union类型(A file system is written and debugged with C,and the function is implemented using the command line.The working process of the simulation of file management.
Explain:
1)each directory item is 16 bytes (defined in 2.2), so only 4 subdirectories or files are allowed in the root directory.
2)i-node bitmap 1 block 64 bytes,a total of 512 bits, can describe the use of 512 i-node
3) the data structure of the bitmap can be referred to as the "bit domain"data structure type.
4) the data blocks in the Data Block area are three types. It includes index blocks, text file data blocks, and directory file data blocks. Use the union type when defining)