What are semaphores in programming and how do they work?

What are semaphores in programming and how do they work?

Semaphores are synchronization tools used to control access to shared resources in concurrent programming. They help prevent race conditions.

Can you explain the difference between binary and counting semaphores?

Sure! A binary semaphore can only take values 0 or 1, while a counting semaphore can take any non-negative integer value, allowing multiple accesses.

How do I implement a semaphore in Python?

In Python, you can use the threading module. Here's a simple example:

import threading

semaphore = threading.Semaphore(2)  # Allows 2 threads to access the resource

def access_resource():
    with semaphore:
        # Critical section
        print('Resource accessed')

What are some common use cases for semaphores?

Common use cases include managing access to a pool of resources, controlling the number of concurrent threads, and implementing producer-consumer scenarios.