setitimer
extern int setitimer(int which, const struct itimerval *value, struct itimerval *oldValue);
if (setitimer(ITIMER_REAL, &itv, NULL) != 0)
if (setitimer(ITIMER_REAL, &itv, NULL) != 0)
if (setitimer(ITIMER_REAL, &value, &oldValue) < 0)
if (setitimer(ITIMER_REAL, &value, &oldValue) < 0)