Starting Open() System Call | 32 Bit OS Dev (in C)

Channel:
United States Queso Fuego
Subscribers:
5,840
Published on ● Video Link: https://www.youtube.com/watch?v=9bw7df00sVc


Duration: 2:07:29
403 views
17

Starting on an open() syscall and file system functions.
OS Dev playlist:
https://www.youtube.com/playlist?list=PLT7NbkyNWaqajsw8Xh7SP9KJwjfpP8TNX

Git Repos:
Sourcehut: https://git.sr.ht/~queso_fuego/quesos
Github mirror: https://github.com/queso-fuego/amateuros

Repo state at start of this video (this will be updated when open() and creating new files is mostly done):
git clone -n https://github.com/queso-fuego/amateuros
cd amateuros
git checkout 4255fe96f1efb69498eec2a55417dd3eca3eb2de

Join the Community Discord: https://discord.gg/yKm4T89QFn

Contact:
email: fuegoqueso@gmail.com
twitter: @Queso_Fuego
twitch: https://www.twitch.tv/queso_fuego

Notes:
- For creating a new regular file vs directory, I'm now thinking (later, after this video was made) that it will be part of a separate process, for a "mkdir" command or similar. That command can call open() with O_CREAT or call a filesystem create file function, update that returned file with the directory file type, and add "." and ".." as default entries to this new directory.

Next video:
- Filling out most of the open() syscall logic

- Let me know if there's anything specific you'd like to see!

Outline:
0:00 changes since last video, bad overview of font conversion program
13:57 open file table typedef
23:50 set up open file table and inode table
32:13 start open() syscall, outline the logic
1:04:34 add & initialize global variables for filesystem
1:28:41 start on fs_impl functions to get inode from file path
2:03:27 complaining about life, coming up, and outro

Questions about setup/software/etc.?
Check the FAQ: https://queso_fuego.srht.site/about.html

Music credits:
"Acid Trumpet" Kevin MacLeod (incompetech.com)
Licensed under Creative Commons: By Attribution 4.0 License
http://creativecommons.org/licenses/by/4.0/

Downtown Glow by Ghostrifter & Devyzed
Creative Commons — Attribution-NoDerivs 3.0 Unported — CC BY-ND 3.0
Music promoted by https://www.chosic.com/free-music/all/

#osdev #bdffonts #systemcalls



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Tags:
queso fuego
low level coding
os dev
operating systems
open system call
open syscall
not linux
homemade os
C programming