c++ extern c

c++ extern c

#include <cstdlib>
#include <fstream>
#include <iomanip>
#include <iostream>

extern "C" {
#include <sys/time.h>
#include <unistd.h>
}
using namespace std;

// === FUNCTION ======================================================================
// Name: main
// Description: main function
// =====================================================================================
int
main ( int argc, char *argv[] )
{
int i = 0, j = 0;
struct timeval tv1, tv2;
double sec = 0;
gettimeofday(&tv1, 0);
for(i = 0; i < 1000000000 ; i++)
{
j++;
}
cout << j << endl;
gettimeofday(&tv2, 0);
sec = (double)(tv2.tv_sec - tv1.tv_sec) + (double)(tv2.tv_usec - tv1.tv_usec) / 1000000;
printf("time1: %f\n", sec);
cout << sec <<endl;
return EXIT_SUCCESS;
} // ---------- end of function main ----------