模拟Linux操作系统shell编程，完全实现其功能，很全面-shell programming

Linux操作系统下的编程，模拟实现了Linux操作系统下的文件系统功能-Programming under the Linux operating system, the simulation under the Linux operating system, file system

硬件模拟器。可以实现Linux环境下的硬件模拟，然后在它上面跑操作系统。-Hardware simulator. Linux can achieve hardware simulation environment, and then run the operating system on top of it