What are the differences between semaphores and locks?

What are the differences 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 explain how semaphores work?

Sure! A semaphore maintains a count that represents the number of available resources. When a thread wants to access a resource, it decrements the count. If the count is zero, the thread must wait until a resource is released and the count is incremented.

What about locks? How do they function?

Locks work by allowing a thread to 'lock' a resource, preventing other threads from accessing it until the lock is released. This ensures mutual exclusion, meaning only one thread can access the resource at a time.

Are there any scenarios where one is preferred over the other?

Yes, semaphores are preferred when you need to control access to a pool of resources, while locks are better for protecting critical sections of code where only one thread should execute.