Event::add

Makes event pending

Description

public bool Event::add( float $timeout = ?)

Marks event pending. Non-pending event will never occur, and the event callback will never be called. In conjunction with Event::del an event could be re-scheduled by user at any time.

If Event::add is called on an already pending event, libevent will leave it pending and re-schedule it with the given timeout(if specified). If in this case timeout is not specified, Event::add has no effect.

Parameters

timeout

Timeout in seconds.

Return Values

Returns true on success or false on failure.

Examples

Example #1 Adding a custom signal

<?php
/*
Launch it in a terminal window:

$ php examples/signal.php

In another terminal window find out the pid and send SIGTERM, e.g.:

$ ps aux | grep examp
ruslan    3976  0.2  0.0 139896 11256 pts/1    S+   10:25   0:00 php examples/signal.php
ruslan    3978  0.0  0.0   9572   864 pts/2    S+   10:26   0:00 grep --color=auto examp
$ kill -TERM 3976

At the first terminal window you should catch the following:

Caught signal 15
*/
class MyEventSignal {
    private $base, $ev;

    public function __construct($base) {
        $this->base = $base;
        $this->ev = Event::signal($base, SIGTERM, array($this, 'eventSighandler'));
        $this->ev->add();
    }

    public function eventSighandler($no, $c) {
        echo "Caught signal $no\n";
        $this->base->exit();
    }
}

$base = new EventBase();
$c    = new MyEventSignal($base);

$base->loop();
?>

The above example will output something similar to:

Caught signal 15

Example #2 Adding a timer

<?php
$base = new EventBase();
$n = 2;
$e = Event::timer($base, function($n) use (&$e) {
    echo "$n seconds elapsed\n";
    $e->delTimer();
}, $n);
$e->add($n);
$base->loop();
?>

The above example will output something similar to:

2 seconds elapsed

See Also

  • Event::add
  • Event::del
  • Event::signal
  • Event::timer