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std::jthrea..._stop_source(3)  C++ Standard Libary std::jthrea..._stop_source(3)

NAME
     std::jthread::get_stop_source - std::jthread::get_stop_source

Synopsis
	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 inter-
     nally 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_possi-
     ble();
	      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

http://cppreference.com 	   2024.06.10	   std::jthrea..._stop_source(3)
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