timer set Create new timer set. Destroy a timer set Callback function for timer event. Add a timer to the set. Returns timer id if OK, -1 on failure. Cancel a timer. Returns 0 if OK, -1 on failure. Set timer interval. Returns 0 if OK, -1 on failure. This method is slow, canceling the timer and adding a new one yield better performance. Reset timer to start interval counting from current time. Returns 0 if OK, -1 on failure. This method is slow, canceling the timer and adding a new one yield better performance. Return the time until the next interval. Should be used as timeout parameter for the zpoller wait method. The timeout is in msec. Invoke callback function of all timers which their interval has elapsed. Should be call after zpoller wait method. Returns 0 if OK, -1 on failure.