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std::stop_token(3)	       C++ Standard Libary	      std::stop_token(3)

NAME
     std::stop_token - std::stop_token

Synopsis
	Defined in header <stop_token>
	class stop_token;		(since C++20)

	The  stop_token  class provides the means to check if a stop request has
     been made or
	can be made, for its associated std::stop_source object.  It  is  essen-
     tially a
	thread-safe "view" of the associated stop-state.

	The  stop_token can also be passed to the constructor of std::stop_call-
     back, such
	that the  callback  will  be  invoked  if  the	stop_token's  associated
     std::stop_source is
	requested  to  stop.  And  stop_token can be passed to the interruptible
     waiting
	functions of std::condition_variable_any,  to  interrupt  the  condition
     variable's wait
	if stop is requested.

Member functions
	constructor    constructs new stop_token object
		       (public member function)
	destructor     destructs the stop_token object
		       (public member function)
	operator=      assigns the stop_token object
		       (public member function)

Modifiers
	swap	       swaps two stop_token objects
		       (public member function)

Observers
	stop_requested	checks	whether  the  associated stop-state has been re-
     quested to stop
		       (public member function)
	stop_possible  checks whether associated stop-state can be requested  to
     stop
		       (public member function)

Non-member functions
	operator==	      compares two std::stop_token objects
			      (function)
	swap(std::stop_token) specializes the std::swap algorithm
	(C++20) 	      (function)

Notes
	A  stop_token  object  is  not	generally constructed independently, but
     rather retrieved
	from a std::jthread or std::stop_source. This makes it	share  the  same
     associated
	stop-state as the std::jthread or std::stop_source.

	Feature-test macro  Value    Std	      Feature
	__cpp_lib_jthread  201911L (C++20) Stop token and joining thread

Example
     // Run this code

      #include <iostream>
      #include <thread>

      using namespace std::literals::chrono_literals;

      void f(std::stop_token stop_token, int value)
      {
	  while (!stop_token.stop_requested())
	  {
	      std::cout << value++ << ' ' << std::flush;
	      std::this_thread::sleep_for(200ms);
	  }
	  std::cout << std::endl;
      }

      int main()
      {
	  std::jthread	thread(f,  5);	// prints 5 6 7 8... for approximately 3
     seconds
	  std::this_thread::sleep_for(3s);
	  // The destructor of jthread calls request_stop() and join().
      }

Possible output:
      5 6 7 8 9 10 11 12 13 14 15 16 17 18 19

http://cppreference.com 	   2024.06.10		      std::stop_token(3)
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