How do I use std::async in C++?

How do I use std::async in C++?

You can use std::async to run tasks asynchronously. It allows you to launch a function in a separate thread.

Can you show me a simple example?

Sure! Here's a basic example:

#include <iostream>
#include <future>

int compute(int x) {
    return x * x;
}

int main() {
    std::future<int> result = std::async(std::launch::async, compute, 5);
    std::cout << "Result: " << result.get() << std::endl;
    return 0;
}

What happens if the function takes a long time to execute?

If the function takes a long time, std::async will still return a future immediately, allowing your main thread to continue executing.

Can I control the execution policy of std::async?

Yes, you can specify the execution policy using std::launch::async or std::launch::deferred to control how the function is executed.