簡単なベンチマークテスト。
Compiler = BCC5.6
OS = WindowsXP Pro

// #define _USE_OLD_RW_STL

#include <iostream>
#include <fstream>
#include <string>
#include <cstdio>
#include <cstdlib>
#include <ctime>
using namespace std;

const int MAXITER = 10000000;
const char *FILENAME = "test.txt";

int main()
{
clock_t cl;
cl = clock();
ofstream ofs(FILENAME);

for (int i = 0; i < MAXITER; i++)
ofs << "1234567890";

ofs.close();
cout << "writing clock = " << clock() - cl << endl;