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// await_keystroke.cpp -----------------------------------------------------//
// Copyright Beman Dawes 2008
// Distributed under the Boost Software License, Version 1.0.
// See http://www.boost.org/LICENSE_1_0.txt
#define _CRT_SECURE_NO_WARNINGS
#include <boost/chrono/chrono.hpp>
#include <iostream>
#include <iomanip>
using namespace boost::chrono;
template< class Clock >
class timer
{
typename Clock::time_point start;
public:
timer() : start( Clock::now() ) {}
typename Clock::duration elapsed() const
{
return Clock::now() - start;
}
double seconds() const
{
return elapsed().count() * ((double)Clock::period::num/Clock::period::den);
}
};
int main()
{
timer<system_clock> t1;
timer<steady_clock> t2;
timer<high_resolution_clock> t3;
std::cout << "Strike any key: ";
std::cin.get();
std::cout << std::fixed << std::setprecision(9);
std::cout << "system_clock-----------: "
<< t1.seconds() << " seconds\n";
std::cout << "steady_clock--------: "
<< t2.seconds() << " seconds\n";
std::cout << "high_resolution_clock--: "
<< t3.seconds() << " seconds\n";
system_clock::time_point d4 = system_clock::now();
system_clock::time_point d5 = system_clock::now();
std::cout << "\nsystem_clock latency-----------: " << (d5 - d4).count() << std::endl;
steady_clock::time_point d6 = steady_clock::now();
steady_clock::time_point d7 = steady_clock::now();
std::cout << "steady_clock latency--------: " << (d7 - d6).count() << std::endl;
high_resolution_clock::time_point d8 = high_resolution_clock::now();
high_resolution_clock::time_point d9 = high_resolution_clock::now();
std::cout << "high_resolution_clock latency--: " << (d9 - d8).count() << std::endl;
std::time_t now = system_clock::to_time_t(system_clock::now());
std::cout << "\nsystem_clock::now() reports UTC is "
<< std::asctime(std::gmtime(&now)) << "\n";
return 0;
}
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