The following code example is taken from the book
The C++ Standard Library - A Tutorial and Reference, 2nd Edition
by Nicolai M. Josuttis, Addison Wesley Longman, 2012
Copyright © 2012 by Pearson Education, Inc. and Nicolai M. Josuttis
#include <chrono>
#include <ctime>
#include <string>
// convert timepoint of system clock to calendar time string
inline
std::string asString (const std::chrono::system_clock::time_point& tp)
{
// convert to system time:
std::time_t t = std::chrono::system_clock::to_time_t(tp);
std::string ts = ctime(&t); // convert to calendar time
ts.resize(ts.size()-1); // skip trailing newline
return ts;
}
// convert calendar time to timepoint of system clock
inline
std::chrono::system_clock::time_point
makeTimePoint (int year, int mon, int day,
int hour, int min, int sec=0)
{
struct std::tm t;
t.tm_sec = sec; // second of minute (0 .. 59 and 60 for leap seconds)
t.tm_min = min; // minute of hour (0 .. 59)
t.tm_hour = hour; // hour of day (0 .. 23)
t.tm_mday = day; // day of month (1 .. 31)
t.tm_mon = mon-1; // month of year (0 .. 11)
t.tm_year = year-1900; // year since 1900
t.tm_isdst = -1; // determine whether daylight saving time
std::time_t tt = std::mktime(&t);
if (tt == -1) {
throw "no valid system time";
}
return std::chrono::system_clock::from_time_t(tt);
}