本源代码所设计的文件系统，具有建立文件（create）、打开文件（open）、读文件（read）、写文件（write）、关闭文件（close）、撤销文件（delete）等功能。在模拟程序中可从键盘上输入文件操作命令来模拟各用户程序中所调用的各种文件操作，用一个结束命令（end）停止程序的执行。-source code designed by the file system, with the establishment of documents (create) open the file (open), reading documents (read), writing paper (write). closure of paper (close), withdrawn document (delete) capabilities. The simulation process from the keyboard input file commands to simulate the user program by calling various documents operation, with the end of a command (end) to stop implementation of the procedures.