+
+/** Return a monotonic value for the number of microseconds that have elapsed
+ * since an arbitrary zero origin.
+ */
+
+#ifdef __MACH__
+/* Thanks Apple for not implementing this basic SUSv2, POSIX.1-2001 function
+ */
+#include <mach/mach_time.h>
+#define CLOCK_REALTIME 0
+#define CLOCK_MONOTONIC 0
+int
+clock_gettime (int /*clk_id*/, struct timespec *t)
+{
+ static bool initialized = false;
+ static mach_timebase_info_data_t timebase;
+ if (!initialized) {
+ mach_timebase_info(&timebase);
+ initialized = true;
+ }
+ uint64_t time;
+ time = mach_absolute_time();
+ double nseconds = ((double)time * (double)timebase.numer)/((double)timebase.denom);
+ double seconds = ((double)time * (double)timebase.numer)/((double)timebase.denom * 1e9);
+ t->tv_sec = seconds;
+ t->tv_nsec = nseconds;
+ return 0;
+}
+#endif
+
+microseconds_t
+ARDOUR::get_microseconds ()
+{
+#ifdef PLATFORM_WINDOWS
+ microseconds_t ret = 0;
+ LARGE_INTEGER freq, time;
+
+ if (QueryPerformanceFrequency(&freq))
+ if (QueryPerformanceCounter(&time))
+ ret = (microseconds_t)((time.QuadPart * 1000000) / freq.QuadPart);
+
+ return ret;
+#else
+ struct timespec ts;
+ if (clock_gettime (CLOCK_MONOTONIC, &ts) != 0) {
+ /* EEEK! */
+ return 0;
+ }
+ return (microseconds_t) ts.tv_sec * 1000000 + (ts.tv_nsec/1000);
+#endif
+}