packaged-task – Tarik Billa

When to use promise over async or packaged_task?

April 5, 2023 by Tarik

std::async std::async is a neat and easy way to get a std::future, but: It does not always start a new thread; the enum value std::launch::async can be passed as the first argument to std::async in order to ensure that a new thread is created to execute the task specified by func, thus ensuring that func … Read more

What is the difference between packaged_task and async

November 14, 2022 by Tarik

Actually the example you just gave shows the differences if you use a rather long function, such as //! sleeps for one second and returns 1 auto sleep = [](){ std::this_thread::sleep_for(std::chrono::seconds(1)); return 1; }; Packaged task A packaged_task won’t start on it’s own, you have to invoke it: std::packaged_task<int()> task(sleep); auto f = task.get_future(); task(); … Read more