How to wait for all Tasks to finish?

[vit-vit]

How to wait for all Tasks to finish?

[pemsley]

Yeah, don't use stop() :-)
This is what I do:
In the main thread, create an atomic int set to 0 (call it thread_count, say). This atomic int is passed to the thread (each thread) as a std::ref() and the thread updates thread_count (adds 1) when it's finished processing, i.e. at the end of the function.
The main thread just waits for the atomic int to match what I expected it to be (10 for 10 threads, say)

    while (thread_count < 10) {
       std::this_thread::sleep_for(std::chrono::milliseconds(1));
    }

This way, somewhere else in the program, using the same thread pool, but (say) doing physics, can keep using threads without interfering.

[Ravenbs]

Thank you.
But found a better way as bussy waiting/polling or with sleep I want to share:

Make a list of Thread handels:
std::vector<std::future> threadhandles;

Start you tasks:
threadhandles.push_back(p.push(....));

Wait all tasks to finish:
for (int i = 0; i < threadhandles.size(); i++)
threadhandles[i].wait();