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+# OS3
+
+Hobby bootable software suite for x86 (NOT x86_64) systems.
+
+## Building
+
+This repository needs 2 separate compilers to function:
+
+ - a generic C/C++ compiler for the "host" (whatever architecture that may be)
+ - a i686-elf GCC/Binutils cross-compiler accessible in the path (i686-elf-gcc, i686-elf-objcopy, etc...)
+
+It also needs mkfs.vfat (or newfs_msdod on macOS).
+
+The build system is cmake.
+
+First, generate the host utilities:
+
+    cmake -S host -B build/host
+    cmake --build build/host
+
+Then, generate the bootable image:
+
+    cmake -S . -B build -DCMAKE_TOOLCHAIN_FILE=CMakeToolchain.txt
+    cmake --build build
+
+The image might run (the `main` branch is not a stable one) via qemu and the following command:
+
+    qemu-system-i386 --hda build/kernel.img
+
+## Components
+
+In order of dependency:
+
+### libfat
+
+Library for handling FAT32 file systems. Can be built for both kernel or host.
+
+### os3_common
+
+Common headers shared between host tools and kernel code.
+
+### host
+
+A collection of host tools required to build the bootable image
+
+### mbr
+
+Stands for "Master Boot Record". It's an assembly file designed to be bootable from MBR x86 systems. (EFI Incompatible).
+
+### stage1
+
+Stage 1 bootloader. Written in C. Should initialize most required drivers (USB, Disks, ACPI, Video). Currently not done.
+
+### rawimg
+
+Disk image. It's built in multiple stages via various host tools.