clock_gettime.h

#ifndef CLOCK_GETTIME_H_
#define CLOCK_GETTIME_H_

#include <windows.h>

#define MS_PER_SEC      1000ULL     // MS = milliseconds
#define US_PER_MS       1000ULL     // US = microseconds
#define HNS_PER_US      10ULL       // HNS = hundred-nanoseconds (e.g., 1 hns = 100 ns)
#define NS_PER_US       1000ULL
#define HNS_PER_SEC     (MS_PER_SEC * US_PER_MS * HNS_PER_US)
#define NS_PER_HNS      (100ULL)    // NS = nanoseconds
#define NS_PER_SEC      (MS_PER_SEC * US_PER_MS * NS_PER_US)

int clock_gettime(int X, struct timespec* tv)
{
  static LARGE_INTEGER ticksPerSec;
  LARGE_INTEGER ticks;

  if (!ticksPerSec.QuadPart)
  {
    QueryPerformanceFrequency(&ticksPerSec);
    if (!ticksPerSec.QuadPart)
    {
      errno = ENOTSUP;
      return -1;
    }
  }

  QueryPerformanceCounter(&ticks);

  tv->tv_sec = (long)(ticks.QuadPart / ticksPerSec.QuadPart);
  tv->tv_nsec = (long)(((ticks.QuadPart % ticksPerSec.QuadPart) * NS_PER_SEC) / ticksPerSec.QuadPart);

  return 0;
}



#endif