#include <sys/time.h>
#include <unistd.h>
#include <stdio.h>

/* The iteration count below needs to be in a reasonable range
   for the specific hardware this program is run on. */

#define ITERATIONS 100000000

/* This program runs furiously away in a loop, doing nothing in
   particular, chewing up lots of processor time.  It will stop only
   when interrupted or killed.  Every ITERATIONS times through its
   loop it prints a report of how long (in microseconds) it took to do
   the last ITERATIONS iterations.  The time is elapsed (wall clock)
   time, so that it includes not only time this process spent, but
   also time when the processor is busy running other processes.  The
   times are not actually accurate to the microsecond.  Important
   note: when compiling this program, do not tell the compiler to
   optimize the program, since doing so might eliminate the inner loop
   entirely.  -Max Hailperin <max@gac.edu> 1999-08-30 */
   

int main(int argc, char *argv[]){
  while(1){ /* Do the timing test repeatedly until killed. */
    struct timeval start, stop;
    long diff, i;
    
    if(gettimeofday(&start, 0) < 0){ /* Get starting time. */
      perror("gettimeofday");
      exit(1);
    }
    for(i = ITERATIONS; i > 0; i--){ /* the actual test */
    /* Do nothing. */
    }
    if(gettimeofday(&stop, 0) < 0){ /* Get ending time. */
      perror("gettimeofday");
      exit(1);
    }
    diff = stop.tv_sec - start.tv_sec;
    diff *= 1000000; /* microseconds per second */
    diff += stop.tv_usec - start.tv_usec;
    printf("%ld\n", diff); /* Print elapsed time. */
  }
}