(PECL ev >= 0.2.0)
EvTimer::again — Restarts the timer watcher
This will act as if the timer timed out and restart it again if it is repeating. The exact semantics are:
if the timer is pending, its pending status is cleared.
if the timer is started but non-repeating, stop it (as if it timed out).
if the timer is repeating, either start it if necessary (with the repeat value), or reset the running timer to the repeat value.
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