What are some examples of compare-and-swap in code?

Can you explain what compare-and-swap is in programming?

Compare-and-swap (CAS) is an atomic operation used in concurrent programming to achieve synchronization.

Can you provide a code example of compare-and-swap?

Sure! Here's a simple example in C++:

bool compare_and_swap(int* target, int expected, int new_value) {
    if (*target == expected) {
        *target = new_value;
        return true;
    }
    return false;
}

How is compare-and-swap used in multithreading?

In multithreading, CAS is used to ensure that only one thread can modify a variable at a time, preventing race conditions.

Are there any drawbacks to using compare-and-swap?

Yes, CAS can lead to issues like livelock and increased contention if many threads are trying to update the same variable.