🧠 Philosophers

A concurrency and synchronization project in C using threads and processes

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📝 Overview

A classic concurrency problem brought to life using threads and mutexes aswell as processes and semaphores.
The Dining Philosophers simulation challenge introduced me to manage shared resources, avoid race conditions and deadlocks. The Philosophers sit together and share Forks, where there are as many forks as philosophers, and philosophers can only eat with two forks.

I implemented two version:

• Multithreaded using pthreads and mutexes
• Multiprocess using semaphores and process control

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✨ Features

• 🧵 Concurrent Philosophers
  Each philosopher is a sepereate Thread or Process.

• 🍽 Protected Resource managment
  Protected Resources managed by Mutexes and Semaphores to prevent race conditions and ensure forks are shared correctly.

• ⏱ Precise Timing
  Millisecond-level timestamp logging.

• ⚰️ Death Detection
  Accurate and timely reporting when a philosopher starves via a seperate mointoring Thread/Process.

• 📦 Optional Argument Support
  Simulation stops early if all philosophers eat a defined number of times.

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🚀 How to Run

🧵 Threads Version

cd philo
make
./philo number_of_philosophers time_to_die time_to_eat time_to_sleep [number_of_times_each_philosopher_must_eat]

🔁 Processes Version

cd philo_bonus
make
./philo_bonus number_of_philosophers time_to_die time_to_eat time_to_sleep [number_of_times_each_philosopher_must_eat]

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⚙ Arguments

Argument	Description
number_of_philosophers	Total number of philosophers (and forks)
time_to_die	Time (ms) a philosopher survives without eating
time_to_eat	Time (ms) a philosopher spends eating
time_to_sleep	Time (ms) a philosopher sleeps after eating
number_of_times_each_must_eat	(Optional) Stops after specified amount of eats

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🪵 Log Format

timestamp_in_ms X has taken a fork
timestamp_in_ms X is eating
timestamp_in_ms X is sleeping
timestamp_in_ms X is thinking
timestamp_in_ms X died

X = philosopher number

• Logs are thread-safe
• "Death" log appears within 10ms of the actual event

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📁 Project Structure

philosophers/
├── philo/                 → threads + mutexes
│   ├── src                → source files
│   ├── inc                → include files
│   └── Makefile
├── philo_bonus/           → processes + semaphores
│   ├── src                → source files
│   ├── inc                → include files
│   └── Makefile
├── docs/                  
└── README.md

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👨‍💻 Authors

• @bartsch-tech