(PECL ev >= 0.2.0)
EvPeriodic::set — Configures the watcher
$offset
   , 
    float
     $interval
   ): void(Re-)Configures EvPeriodic watcher
offset
    The same meaning as for EvPeriodic::__construct() . See Periodic watcher operation modes
interval
    The same meaning as for EvPeriodic::__construct() . See Periodic watcher operation modes
没有返回值。