#include <iostream>
#include <future>
#include <thread>
#include <chrono>
 
#define LOG()	std::cout << __func__ << " : "
 
void test()
{
	LOG() << "IN\n";
 
	using namespace std::chrono_literals;
	std::this_thread::sleep_for( 1s );
 
	LOG() << "OUT\n";
}
 
int main()
{
	LOG() << "Calling test()...\n";
 
	auto f = std::async( std::launch::async, test );
 
	LOG() << "Running test()...\n";
 
	// ...                             ...
	// ... You can do other stuff here ...
	// ...                             ...
 
	f.wait(); // Blocking call to wait for the result to be available
 
	LOG() << "Exiting...\n";
 
	return 0;
}

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