C++ performance test - '\n' vs std::endl

performance_newline.cpp

// Timing the performance
// Example: '\n' vs std::endl

// The winner is given at the end

#include <cmath>
#include <iostream>
#include <fstream>

#include <time.h>

constexpr long MAX = 19999999;

int main() {
  std::ofstream f("test_time.dat");
  std::ofstream o("test_run.out");
  clock_t t1, t2, diff;

  t1=clock();
  for(int i = 0; i < MAX; ++i) o << std::endl;
  t2=clock();

  diff = ((float) t2 - (float) t1);
  
  f << "std::endl : " << diff << std::endl;

  t1 = clock();
  for(int i = 0; i < MAX; ++i) o << '\n';
  t2 = clock();

  diff = ((float) t2 - (float) t1);
  f << "\'\\n\' : " << diff << '\n';  

  f.close(); o.close();
}

/*
  Results:

  * Run 1 : MAX = 199999
  std::endl : 266843
  '\n' : 8810
  
  * Run 2 : MAX = 1999999
  std::endl : 2504474
  '\n' : 67492
  
  * Run 3 : MAX = 19999999
  std::endl : 25223044
  '\n' : 679572
 */