---

🧠 RohitOS v0.1 — A Minimal Custom Operating System

A fully handcrafted operating system from scratch in C + Assembly, booting with a custom bootloader, entering protected mode, and running a feature-rich CLI

---

📽️ Demo

OS.VIDEO.ROHIT.mp4

---

🧱 Project Structure

RohitOS/
├── bootloader.asm # 16-bit bootloader to load kernel
├── disk_load.asm # Sector loader (INT 13h)
├── gdt.asm # GDT for protected mode
├── kernel/
│ ├── kernel_entry.asm # Jump into 32-bit mode
│ ├── kernel.c # Core logic, splash, progress, init
│ ├── cli.c # Command parser + dispatcher
│ └── cli.h # CLI header
├── lib/
│ ├── stdio.c/.h # Custom print() and console I/O
│ └── string.c/.h # Basic string ops (no libc)
├── linker.ld # Custom linker script
├── Makefile # Complete build system
├── build/ # Compiled output binaries
└── README.md # This file 📄

---

🚀 Features

• 🔹 Custom 16-bit bootloader
• 🔹 Protected mode (32-bit) kernel
• 🔹 Fully functional CLI shell
• 🔹 ASCII splash screen + loading bar
• 🔹 No libc – all string/IO functions built manually
• 🔹 System uptime tracking
• 🔹 Custom command parsing
• 🔹 Print with no standard output
• 🔹 Written in pure C and NASM

---

🖥️ CLI Commands

Command	Description
help	Show all commands
clear	Clear the terminal screen
ver	Show OS version
uptime	Show system uptime in seconds
date	Show kernel build date/time
whoami	Print the current user
sysinfo	Show system info summary
shutdown	Halt execution (hlt loop)
echo	Print custom text
calc	Add, subtract, multiply, divide
timer	Countdown timer
hex	Convert decimal to hexadecimal
bin	Convert decimal to binary
fortune	Show a random coding quote

---

🧪 Build & Run Instructions

🛠 Requirements

• nasm
• gcc with 32-bit support (-m32)
• ld
• QEMU (or Bochs/VirtualBox for ISO testing)

🔨 Commands

make clean
make        # Assembles + compiles everything
make run    # Runs RohitOS in QEMU

---

🌟 Author

Rohit Yadav 🎓 CS Undergrad @ NIT Jalandhar 👨‍💻 Systems Programmer | VM + Compiler Dev

---

⭐ If you liked it — drop a star!