/* Measure CPU speed in ticks per second */

#include <stdio.h>
#include <unistd.h>

unsigned long long rdtsc (void) {
  unsigned long long returned;
  asm volatile (" rdtsc " : "=A" (returned));
  return returned;
}

int main(void) {
  unsigned long long prevtime = rdtsc();
  sleep(1);
  unsigned long long newtime = rdtsc();
  printf("Current CPU speed: %.0fMhz\n", (newtime - prevtime) / 1000000.0);
  return 0;
}