(PECL ev >= 0.2.0)
$value= ?): bool
true if the watcher is active.
User custom data associated with the watcher
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
change its priority.
. Pending watchers with higher priority will be invoked before watchers
with lower priority, but priority will not keep watchers from being
watchers provide functionality to suppress invocation when higher
priority events are pending.