C++ timestamp [15 characters]

timestamp.cpp

#include <iostream>
#include <iomanip>
#include <sstream>
#include <chrono>
#include <ctime>

std::string get_timestamp() noexcept
{
    const auto now = std::chrono::system_clock::now();
    const auto time = std::chrono::system_clock::to_time_t(now);
    const auto ms = std::chrono::duration_cast<std::chrono::milliseconds>(now.time_since_epoch()) -
                    std::chrono::duration_cast<std::chrono::seconds>(now.time_since_epoch());
    std::ostringstream oss;
    oss << std::put_time(std::localtime(&time), "%d%m%yT%H%M%S") << ms.count();
    return oss.str();
}

int main()
{
    std::cout << get_timestamp();
}