Skip site navigation (1)Skip section navigation (2)

FreeBSD Manual Pages

  
 
  

home | help 
std::stop_t...op_requested(3) C++ Standard Libarystd::stop_t...op_requested(3)

NAME
       std::stop_token::stop_requested - std::stop_token::stop_requested

Synopsis
	  [[nodiscard]]	bool stop_requested() const noexcept;  (since C++20)

	  Checks  if  the stop_token object has	associated stop-state and that
       state has
	  received a stop request. A default constructed stop_token has	no as-
       sociated
	  stop-state, and thus has not had stop	requested.

Parameters
	  (none)

Return value
	  true if the stop_token object	has associated stop-state and  it  re-
       ceived a	stop
	  request, false otherwise.

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_token& to-
       ken)
	    {
		std::cout << name << ":	stop_possible =	" << token.stop_possi-
       ble();
		std::cout << ",	stop_requested = "  <<	token.stop_requested()
       << '\n';
	    };

	    // A worker	thread that will listen	to stop	requests
	    auto stop_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";
		}
	    });

	    // A worker	thread that will only stop when	completed
	    auto inf_worker = std::jthread([]()
	    {
		for (int i = 5;	i; --i)
		{
		    std::this_thread::sleep_for(300ms);
		    std::cout << "  Run	as long	as we want\n";
		}
	    });

	    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::stop_t...op_requested(3)

Want to link to this manual page? Use this URL:
<https://man.freebsd.org/cgi/man.cgi?query=std::stop_token::stop_requested&sektion=3&manpath=FreeBSD+Ports+15.1.quarterly>

home | help