How to create an OS from scratch
How to create an OS from scratch!
I have always wanted to learn how to make an OS from scratch. In college I was taught how to implement advanced features (pagination, semaphores, memory management, etc) but:
Inspired by this document and the OSDev wiki, I'll try to make short step-by-step READMEs and code samples for anybody to follow. Honestly, this tutorial is basically the first document but split into smaller pieces and without the theory.
Start with the first folder and go down in order. They build on previous code, so if you jump right to folder 05 and don't know why there is a
mov ah, 0x0e, it's because you missed lecture 02. Really, just go in order. You can always skip stuff you already know.
Open the README and read the first line, which details the concepts you should be familiar with before reading the code. Google concepts you are not familiar with. The second line states the goals for each lesson. Read them, because they explain why we do what we do. The "why" is as important as the "how".
Read the rest of the README. It is very concise.
(Optional) Try to write the code files by yourself after reading the README.
Look at the code examples. They are extremely well commented.
(Optional) Experiment with them and try to break things. The only way to make sure you understood something is trying to break it or replicate it with different commands.
TL;DR: First read the README on each folder, then the code files. If you're brave, try to code them yourself.
We will want to do many things with our OS:
libcwhich grows to suit our needs - DONE!
Probably we will go through them in that order, however it's soon to tell.
If we feel brave enough:
This is a personal learning project, and even though it hasn't been updated for a long time, I still have hopes to get into it at some point.
I'm thankful to all those who have pointed out bugs and submitted pull requests. I will need some time to review everything and I cannot guarantee that at this moment.
Please feel free to fork this repo. If many of you are interested in continuing the project, let me know and I'll link the "main fork" from here.