Operating Systems Lab Repository

This repository contains a collection of Operating Systems lab programs organized by topic, implemented primarily in C and Shell Scripting. It includes solutions to synchronization problems, inter-process communication, threading, memory management, system calls, and more.

⚠️ Note: Some programs are intended to be compiled and run on Linux (Ubuntu) systems only, as they make use of Linux-specific headers and system calls.

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🗂 Folder Structure

operating-systems/
│
├── ShellScripting/             # Advanced shell script programs
├── basic-shell-scripting/     # Basic shell scripting concepts
├── SystemCalls/               # Programs using system calls like fork, exec, wait
├── ipc/                       # Inter-process communication (shared memory, message queues)
├── synchronization/           # Synchronization problems like Producer-Consumer, Dining Philosophers
├── threads/                   # POSIX thread-based programs
│
├── Bankers_latest.c           # Banker's Algorithm (Resource Allocation)
├── Bankers_latest_safety.c    # Banker's Algorithm (Safety Check)
├── Mem_allocation_latest.c    # Memory Allocation Strategies
├── disk_scheduling.c          # Disk Scheduling Algorithms
├── page_replace_latest.c      # Page Replacement Algorithms
├── scheduling_latest.c        # CPU Scheduling Algorithms
└── .gitignore

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📁 Directory Details

1. ShellScripting/

• Contains shell scripts for:

  • File search
  • Fibonacci series
  • Command-line argument processing
  • Simple calculators

2. basic-shell-scripting/

• Basic concepts of shell scripting:

  • Variables, arrays, loops
  • Arithmetic operations
  • Conditional branching

3. SystemCalls/

• C programs using:

  • fork(), exec(), wait()
  • File operations using open(), read(), write()
  • Process management

4. ipc/ (Inter-Process Communication)

• Programs demonstrating:

  • Shared memory (shmget, shmat, etc.)
  • Message queues
  • Chat applications using message queues
  • Producer-consumer problem with shared memory

5. synchronization/

• Classic synchronization problems:

  • Peterson's solution
  • Producer-consumer using semaphores
  • Dining Philosophers
  • Reader-Writer problem

6. threads/

• Programs using POSIX threads:

  • Creating threads
  • Printing odd-even numbers using threads
  • Returning values from threads

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⚙️ Linux-Only Files

These files include Linux-specific headers (<unistd.h>, <sys/types.h>, <sys/ipc.h>, <pthread.h>, etc.) and must be compiled/run on a Linux environment (e.g., Ubuntu):

• All files inside:

  • SystemCalls/
  • ipc/
  • synchronization/
  • threads/

📌 Use gcc or gcc -pthread (for thread programs) to compile.

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🧪 How to Run

On Ubuntu/Linux:

# Compile a C file
gcc filename.c -o output

# For thread programs
gcc filename.c -o output -pthread

# Run the compiled binary
./output

Shell Scripts:

# Make script executable
chmod +x script.sh

# Run script
./script.sh

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📌 Requirements

• GCC compiler (sudo apt install build-essential)
• Shell (bash)
• Linux environment (preferably Ubuntu)

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📜 License

This project is for academic and learning purposes only. You are free to use and modify it for personal or educational use.