(PECL ev >= 0.2.0)
EvWatcher::clear — Clear watcher pending status
If the watcher is pending, this method clears its
pending
status and returns its
revents
bitset(as if its callback was invoked). If the watcher isn't pending
it does nothing and returns
0
.
Sometimes it can be useful to "poll" a watcher instead of waiting for its callback to be invoked, which can be accomplished with this function.
此函数没有参数。
In case if the watcher is pending, returns
revents
bitset as if the
watcher callback
had been invoked. Otherwise returns
0
.