What are some examples of semaphore usage?

What are some examples of semaphore usage?

Semaphores are often used in programming to control access to shared resources. For example, in a multi-threaded application, a semaphore can limit the number of threads that access a particular resource at the same time.

Can you give me a specific programming example?

Sure! In a Java application, you might use a Semaphore class to limit access to a database connection pool. If you set the semaphore count to 5, only 5 threads can access the database at once.

What happens if all permits are taken?

If all permits are taken, any additional threads that try to acquire the semaphore will be blocked until a permit is released by another thread.

Are there any other use cases for semaphores?

Yes, semaphores can also be used in scenarios like controlling access to a critical section in concurrent programming, managing resource allocation in operating systems, and even in network programming to limit the number of simultaneous connections.