(PECL ev >= 0.2.0)
Ev::now — Returns the time when the last iteration of the default event loop has started
Returns the time when the last iteration of the default event loop has started. This is the time that timers( EvTimer and EvPeriodic) are based on, and referring to it is usually faster then calling Ev::time().
此函数没有参数。
Returns number of seconds(fractional) representing the time when the last iteration of the default event loop has started.