(PECL ev >= 0.2.0) Abstract constructor of a watcher object

(PECL ev >= 0.2.0) Invokes the watcher callback with the given received events bit mask

(PECL ev >= 0.2.0) Configures whether to keep the loop from returning

(PECL ev >= 0.2.0) Starts the watcher public

(PECL ev >= 0.2.0) Stops the watcher public

(PECL ev >= 0.2.0) Clear watcher pending status

(PECL ev >= 0.2.0) Feeds the given revents set into the event loop

(PECL ev >= 0.2.0) Sets new callback for the watcher

(PECL ev >= 0.2.0) Returns the loop responsible for the watcher