+static void format_duration (char *buf, size_t len, int64_t duration)
+{
+ lldiv_t d;
+ int sec;
+
+ duration /= CLOCK_FREQ;
+ d = lldiv (duration, 60);
+ sec = d.rem;
+ d = lldiv (d.quot, 60);
+ snprintf (buf, len, "%02lld:%02d:%02d", d.quot, (int)d.rem, sec);
+}
+