What is the difference between locks and semaphores in programming?

What is the difference between locks and semaphores in programming?

Locks and semaphores are both synchronization primitives used to control access to shared resources in concurrent programming. A lock allows only one thread to access a resource at a time, while a semaphore can allow multiple threads to access a resource, up to a specified limit.

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

Sure! Use a lock when you need exclusive access to a resource, like updating a shared variable. Use a semaphore when you want to limit access to a resource, like a pool of database connections.

What are the potential issues with using locks?

Using locks can lead to issues like deadlocks, where two or more threads are waiting indefinitely for each other to release locks, and priority inversion, where lower-priority threads hold locks needed by higher-priority threads.

Are there any best practices for using semaphores?

Yes, some best practices include initializing semaphores with the correct count, avoiding unnecessary complexity, and ensuring that all threads properly release the semaphore after use.