简介

EvWatcher is a base class for all watchers( EvCheck , EvChild etc.). Since EvWatcher 's constructor is abstract , one can't(and don't need to) create EvWatcher objects directly.

类摘要

属性

is_active

Readonly . true if the watcher is active. false otherwise.

data

User custom data associated with the watcher

is_pending

Readonly .true if the watcher is pending, i.e. it has outstanding events, but its callback has not yet been invoked. false otherwise. As long, as a watcher is pending(but not active), one must not change its priority.

priority

int between Ev::MINPRI and Ev::MAXPRI . Pending watchers with higher priority will be invoked before watchers with lower priority, but priority will not keep watchers from being executed(except for EvIdle watchers). EvIdle watchers provide functionality to suppress invocation when higher priority events are pending.