os64

A 64-bit x86 operating system built for educational purposes.

Getting Started

Prerequisites

Before you begin, ensure you have the following software installed on your system:

• make: To build the project.
• QEMU: To run the operating system in a virtual machine.
• xorriso: To create the bootable ISO image.
• git: To clone the required dependencies.
• A C compiler: Such as GCC or Clang.

Building and Running

1. Clone the repository:

   git clone git@github.com:VBWizard/os64.git
   cd os64

2. Build the operating system:

   The following command will build the kernel and create a bootable ISO image named os64_kernel.iso:

   make

3. Run the operating system:

   To run the operating system in QEMU, use the following command:

   make run

   This will start a QEMU virtual machine and boot from the os64_kernel.iso image.

Debugging

To run the operating system in debugging mode, use the following command:

make debug

This will start QEMU with the GDB server enabled, allowing you to connect a debugger to inspect the operating system.

Other Commands

The GNUmakefile provides several other useful commands:

• make clean: Removes the build artifacts.
• make distclean: Removes the build artifacts and all downloaded dependencies.
• make run-uefi: Runs the operating system in UEFI mode.
• make run-hdd: Runs the operating system from a virtual hard disk image.

For more details, refer to the GNUmakefile in the root of the project.

Running in VirtualBox

The VirtualBox VM boots its DVD from C:/temp/os64_kernel.iso, which a normal make refreshes automatically — so kernel changes reach VirtualBox with no extra steps. The VM's hard disk (OS64_NVME.vdi, attached to the NVMe controller) holds the same filesystem content as disk/os64.img and must be synced whenever the disk contents change (new test binaries, libraries, etc.):

make vbox-sync

The VM must be powered off when running this. The VDI is a fixed-format image, so the sync is a single dd of the raw disk image into the VDI's data area — the medium UUID VirtualBox has registered is untouched. The one-time procedure for recreating the VDI (needed only if DISK_SIZE_MB changes) is documented in comments above the vbox-sync target in the GNUmakefile.