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README.md

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+# Writing an Operating System in 1,000 Lines
+My implementation of https://operating-system-in-1000-lines.vercel.app/en
+A small operating system written from scratch for RISC-V CPU architecture
+
+This project will have basic context switching, paging, user mode, a command-line shell, a disk device driver, and file read/write operations in C.
+And also I'll try to add some more functionality to it
+
+![Operating System in 1,000 Lines](./screenshot.png)
+
+# Getting Started
+You have to be on UNIS-like OS to run this OS. If you're on Windows you need to install WSL2 (Windows Subsystem for Linux) and follow Ubuntu instructions
+
+## Install tools
+
+### macOS 
+
+Install [Homebrew](https://brew.sh) and run this command to get all tools you need:
+
+```
+brew install llvm lld qemu
+```
+
+Also, you need to add LLVM binutils to your `PATH`:
+
+```
+$ export PATH="$PATH:$(brew --prefix)/opt/llvm/bin"
+$ which llvm-objcopy
+/opt/homebrew/opt/llvm/bin/llvm-objcopy
+```
+
+### Ubuntu
+
+Install packages with `apt`:
+
+```
+sudo apt update && sudo apt install -y clang llvm lld qemu-system-riscv32 curl
+```
+
+Also, download OpenSBI (think of it as BIOS/UEFI for PCs):
+
+```
+curl -LO https://github.com/qemu/qemu/raw/v8.0.4/pc-bios/opensbi-riscv32-generic-fw_dynamic.bin
+```
+
+> [!WARNING]
+>
+> When you run QEMU, make sure `opensbi-riscv32-generic-fw_dynamic.bin` is in your current directory. If it's not, you'll see this error:
+>
+> ```
+> qemu-system-riscv32: Unable to load the RISC-V firmware "opensbi-riscv32-generic-fw_dynamic.bin"
+> ```
+
+### Other OS users
+
+If you are using other OSes, get the following tools:
+
+- `bash`: The command-line shell. Usually it's pre-installed.
+- `tar`: Usually it's pre-installed. Prefer GNU version, not BSD.
+- `clang`: C compiler. Make sure it supports 32-bit RISC-V CPU (see below).
+- `lld`: LLVM linker, which bundles complied object files into an executable.
+- `llvm-objcopy`: Object file editor. It comes with the LLVM package (typically `llvm` package).
+- `llvm-objdump`: A disassembler. Same as `llvm-objcopy`.
+- `llvm-readelf`: An ELF file reader. Same as `llvm-objcopy`.
+- `qemu-system-riscv32`: 32-bit RISC-V CPU emulator. It's part of the QEMU package (typically `qemu` package).
+
+> [!TIP]
+>
+> To check if your `clang` supports 32-bit RISC-V CPU, run this command:
+>
+> ```
+> $ clang -print-targets | grep riscv32
+>     riscv32     - 32-bit RISC-V
+> ```
+>
+> You should see `riscv32`. Note pre-installed clang on macOS won't show this. That's why you need to install another `clang` in Homebrew's `llvm` package.