How can I use semaphores in programming?

How can I use semaphores in programming?

Semaphores are synchronization tools used to control access to a common resource in concurrent programming. Would you like an example?

Yes, please provide an example of using semaphores.

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

import threading
import time

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

def access_resource(thread_id):
    print(f'Thread {thread_id} is trying to access the resource.')
    semaphore.acquire()
    print(f'Thread {thread_id} has accessed the resource.')
    time.sleep(2)  # Simulate resource usage
    print(f'Thread {thread_id} is releasing the resource.')
    semaphore.release()

for i in range(5):
    threading.Thread(target=access_resource, args=(i,)).start()

What does the acquire and release method do?

The acquire method decreases the semaphore count, blocking if the count is zero, while release increases it, allowing other threads to access the resource.