What is the difference between semaphores and locks?

What is the difference between semaphores and locks?

Semaphores and locks are both synchronization primitives used in concurrent programming, but they serve different purposes. A lock is used to ensure that only one thread can access a resource at a time, while a semaphore can allow multiple threads to access a resource up to a certain limit.

Can you give me an example of when to use a semaphore?

Sure! You might use a semaphore in a scenario where you have a pool of resources, like database connections. If you have a maximum of 5 connections, you can use a semaphore initialized to 5 to control access, allowing up to 5 threads to use the connections simultaneously.

What about deadlocks? How do they relate to locks?

Deadlocks can occur when two or more threads are waiting for each other to release locks. To avoid deadlocks, you can use techniques like lock ordering or implementing a timeout for acquiring locks.

Are semaphores safer than locks?

Not necessarily. Both semaphores and locks can lead to issues like deadlocks or race conditions if not used properly. The choice between them depends on the specific use case and requirements of your application.