There are too many expriments this semester.
As for OS, recompiling the Linux kernel is the very first job to do intending to add a new system function. I managed it under Ubuntu 16.04, 4.4.0.
And then I finished writing a simulation of file management which implemented mkdir, rmdir, touch, delete, cd, pwd and so on.

## Recompile Kernel

### Preparation

First you need a VMware machine. There are many tutorials on the Internet.
Then you need the source code of linux kernel and the tools to compile it.

### Use The New Kernel

Write test.c like:

## Filesystem Simulation

The following code still needs some tests.