building an OS (all streams)

Currently Playing: building my own operating system in c++ (week 103, x86_64 interrupts)

(detailed timestamps in comments) #livecoding #operatingsystem #coding welcome: https://offlinemark.com/welcome discord: https://discord.gg/P6zQBsD2ng Welcome! I’m an aspiring systems programmer. Professionally, I used to work in infosec, but now I work on music production software & hardware. I stream OS/kernel development every week for 2 hours. (I’ve done this for over 75 weeks in a row! Sundays 10a-12 ET) From February 2024 to May 2025, I streamed myself doing all the labs for MIT’s old Operating Systems Engineering course (6.828 (2018)). Through doing this, I became very familiar with JOS, which is the x86 OS used for the course. I had almost no experience with OS development when I started, although I did have much experience with programming and low level concepts. I did the coursework because I wanted to write my own OS, but felt I wasn’t ready. Now, from May 2025 to present, I’m pursuing my own learning agenda with OS development, and starting my on own OS. If this resonates with you, please subscribe and I'll see you in a stream :) 00:00:00 Start 00:03:57 – Planning the components needed for interrupt handling: GDT, IDT, assembly handlers, and C++ trap handler 00:08:24 – Decision to use Lemony's existing GDT instead of creating a custom one 00:26:02 – Starting implementation of IDT structure and basic setup 00:36:42 – Creating IDT gate descriptor structure with AI assistance for bit field layout 00:45:22 – Implementing functions to initialize IDT entries with proper offset splitting 01:16:02 – Creating IDTR structure and loading the IDT into the processor 01:39:37 – Testing the interrupt handler by triggering a divide by zero exception 01:42:24 – Successful verification that the first exception handler is working 01:49:17 – Planning next steps: implementing trap frames and C++ handlers for complete interrupt handling