What are some examples of asynchronous programming in C++?

What are some examples of asynchronous programming in C++?

Asynchronous programming in C++ can be achieved using features like std::async, futures, and promises. Would you like to see a specific example?

Yes, please provide an example using std::async.

Sure! Here's a simple example:

#include <iostream>
#include <future>
#include <chrono>

int asyncTask() {
    std::this_thread::sleep_for(std::chrono::seconds(2));
    return 42;
}

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

This code runs asyncTask asynchronously and retrieves the result after waiting.

What does std::launch::async do in this example?

std::launch::async ensures that the task is run on a new thread, allowing it to execute concurrently with the main thread.

Can you explain futures and promises in C++?

Certainly! Futures and promises are used for communication between threads. A promise is a way to set a value that a future can retrieve later. This allows one thread to produce a value while another thread consumes it.