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PaulOS

My take on geohot's fromthetransistor operating system section (section 5)

Kernel Design: Monolithic

Linux-ish:
* only user space threads
* open, read, write, close
* fork, execve, wait, sleep, exit
* mmap, munmap, mprotect
* Consider the debug interface you are using, ranging from printf to perhaps a gdbremote stub into kernel


Requirements:
- make
- cross compiler for i386 (check out [https://wiki.osdev.org/GCC_Cross-Compiler])
- grub
- xorriso
- qemu
NOTE: these requriements are not exactly the packages needed to be installed


Build:
./build.sh

Clean:
./clean.sh

Run (using qemu-system-i386):
./run.sh

For multiboot kernel (directly without bootable medium):
$ qemu-system-i386 -kernel PaulOS.bin


STEPS:
- interrupt handlers
- process management
- paging + memory map (physical first, then paging)
- usermode -> syscalls (open, read, write, ...)
- shell
- drivers(?)
- filesystem


TODO:
* output object files in build/ (modify Makefile)
* replace "" with <> in includes

* implement interrupts and exceptions
* plan memory map (virtual and physical)
* move on with syscalls
* malloc/free (mmap, munmap, mprotect)
* open, read, write, close
* fork, execve, wait, sleep, exit
* build drivers

check out:
- https://wiki.osdev.org/Main_Page
- https://github.com/SerenityOS/serenity