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

NAME
     std::jthread::get_stop_token - std::jthread::get_stop_token

Synopsis
	std::stop_token get_stop_token() const noexcept;  (since C++20)

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

Parameters
	(none)

Return value
	A value of type std::stop_token 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;

      void print(std::string_view name, const std::stop_token& token)
      {
	  std::cout << name << ": stop_possible = " << token.stop_possible();
	  std::cout << ", stop_requested = " << token.stop_requested() << '\n';
      }

      void finite_sleepy(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";
	  }
      }

      void infinite_sleepy()
      {
	  for (int i = 5; i; --i)
	  {
	      std::this_thread::sleep_for(300ms);
	      std::cout << "  Run as long as we want\n";
	  }
      }

      int main()
      {
	  std::cout << std::boolalpha;

	  // A worker thread that will listen to stop requests
	  std::jthread stop_worker(finite_sleepy);

	  // A worker thread that will only stop when completed
	  std::jthread inf_worker(infinite_sleepy);

	  std::stop_token def_token;
	  std::stop_token stop_token = stop_worker.get_stop_token();
	  std::stop_token inf_token = inf_worker.get_stop_token();
	  print("def_token ", def_token);
	  print("stop_token", stop_token);
	  print("inf_token ", inf_token);

	  std::cout << "\nRequest and join stop_worker:\n";
	  stop_worker.request_stop();
	  stop_worker.join();

	  std::cout << "\nRequest and join inf_worker:\n";
	  inf_worker.request_stop();
	  inf_worker.join();
	  std::cout << '\n';

	  print("def_token ", def_token);
	  print("stop_token", stop_token);
	  print("inf_token ", inf_token);
      }

Possible output:
      def_token : stop_possible = false, stop_requested = false
      stop_token: stop_possible = true, stop_requested = false
      inf_token : stop_possible = true, stop_requested = false

      Request and join stop_worker:
	Run as long as we want
	Sleepy worker is requested to stop

      Request and join inf_worker:
	Run as long as we want
	Run as long as we want
	Run as long as we want
	Run as long as we want

      def_token : stop_possible = false, stop_requested = false
      stop_token: stop_possible = true, stop_requested = true
      inf_token : stop_possible = true, stop_requested = true

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