php man page for event_timer_set

EVENT_TIMER_SET(3)							 1							EVENT_TIMER_SET(3)

event_timer_set - Prepare a timer event

SYNOPSIS
       bool event_timer_set (resource  $event, callable  $callback, [mixed  $arg])

DESCRIPTION
	Prepares  the timer event to be used in event_add(3). The event is prepared to call the function specified by the $callback when the event
       timeout elapses.

	After initializing the event, use event_base_set(3) to associate the event with its event base.

	In case of matching event, these three arguments are passed to the $callback function:

	      o $fd
		- Signal number or resource indicating the stream.

	      o $events
		- A flag indicating the event. This will always be EV_TIMEOUT for timer events.

	      o $arg
		- Optional parameter, previously passed to event_timer_set(3) as $arg.

PARAMETERS
	      o $event
		- Valid event resource.

	      o $callback
		- Callback function to be called when the matching event occurs.

	      o $arg
		- Optional callback parameter.

RETURN VALUES
	Returns TRUE on success or FALSE on failure.

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