# std::chrono::steady_clock::now

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< cpp‎ | chrono‎ | steady clock

static std::chrono::time_point<std::chrono::steady_clock> now() noexcept; |  | (since C++11)

Returns a time point representing the current point in time.

### Parameters

(none)

### Return value

A time point representing the current time.

### Example

Run this code

    #include <iostream>
    #include <iomanip>
    #include <vector>
    #include <numeric>
    #include <chrono>

    volatile int sink;
    int main()
    {
        std::cout << std::fixed << std::setprecision(9) << std::left;
        for (auto size = 1ull; size < 1000'000'000ull; size *= 100) {
            // record start time
            auto start = std::chrono::steady_clock::now();
            // do some work
            std::vector<int> v(size, 42);
            sink = std::accumulate(v.begin(), v.end(), 0u); // make sure it's a side effect
            // record end time
            auto end = std::chrono::steady_clock::now();
            std::chrono::duration<double> diff = end - start;
            std::cout << "Time to fill and iterate a vector of " << std::setw(9)
                      << size << " ints : " << diff.count() << " s\n";
        }
    }

Possible output:

    Time to fill and iterate a vector of 1         ints : 0.000006568 s
    Time to fill and iterate a vector of 100       ints : 0.000002854 s
    Time to fill and iterate a vector of 10000     ints : 0.000116290 s
    Time to fill and iterate a vector of 1000000   ints : 0.011742752 s
    Time to fill and iterate a vector of 100000000 ints : 0.505534949 s

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