stop_source

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Stop sources provide a means to issue thread stop requests. A stop request asks a thread to stop execution. Stop sources can send stop requests to multiple threads simultaneously.

The stop request does not need to be honoured by the signalled thread(s). To honour the stop request, construct a stop_token from the stop_source and check the function named stop_requested() .

#include <iostream>
#include <syncstream>

#include <thread>

void task
   (
   unsigned
      thread_id
         ,
   ::std::stop_source
      source
   )
{
   auto
      stop_token = source.get_token();
   
   while
      (
         not stop_token.stop_requested()
      )
   {
      ::std::this_thread::sleep_for
         (
         ::std::chrono::seconds(1)
         )
         ;
   }
   
   ::std::osyncstream(::std::cout) << "Thread "
                                   << thread_id
                                   << " stopped"
                                   << ::std::endl
                                      ;
}

int main(int argc, char ** argv)
{
   ::std::stop_source
      source;
   
   ::std::jthread t0( task, 0u, source );
   ::std::jthread t1( task, 1u, source );
   ::std::jthread t2( task, 2u, source );
   ::std::jthread t3( task, 3u, source );
   
   ::std::this_thread::sleep_for
      (
      ::std::chrono::seconds(5)
      )
      ;
   
   //
   // Stop all 4 threads:
   //
   
   source.request_stop();
   
   return 0;
}