# std::jthread::get_stop_source

From cppreference.com
< cpp‎ | thread‎ | jthread

std::stop_source get_stop_source() noexcept; |  | (since C++20)

Returns a std::stop_source associated with the same shared stop-state as held internally by the `jthread` object.

### Parameters

(none)

### Return value

A value of type std::stop_source associated with stop-state held internally by `jthread` object.

### Example

Run this code

    #include <chrono>
    #include <condition_variable>
    #include <iostream>
    #include <mutex>
    #include <string_view>
    #include <thread>

    using namespace std::chrono_literals;

    int main()
    {
        std::cout << std::boolalpha;
        auto print = [](std::string_view name, const std::stop_source& source)
        {
            std::cout << name << ": stop_possible = " << source.stop_possible();
            std::cout << ", stop_requested = " << source.stop_requested() << '\n';
        };

        // A worker thread
        auto worker = std::jthread([](std::stop_token stoken)
        {
            for (int i = 10; i; --i)
            {
                std::this_thread::sleep_for(300ms);
                if (stoken.stop_requested())
                {
                    std::cout << "  Sleepy worker is requested to stop\n";
                    return;
                }
                std::cout << "  Sleepy worker goes back to sleep\n";
            }
        });

        std::stop_source stop_source = worker.get_stop_source();
        print("stop_source", stop_source);

        std::cout << "\nPass source to other thread:\n";
        auto stopper = std::thread(
            [](std::stop_source source)
            {
                std::this_thread::sleep_for(500ms);
                std::cout << "Request stop for worker via source\n";
                source.request_stop();
            },
            stop_source);
        stopper.join();
        std::this_thread::sleep_for(200ms);
        std::cout << '\n';

        print("stop_source", stop_source);
    }

Possible output:

    stop_source: stop_possible = true, stop_requested = false

    Pass source to other thread:
      Sleepy worker goes back to sleep
    Request stop for worker via source
      Sleepy worker is requested to stop

    stop_source: stop_possible = true, stop_requested = true

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