(PECL pthreads >= 2.0.0)
Threaded::notify — Synchronization
Send notification to the referenced object
This function has no parameters.
A boolean indication of success
Example #1 Notifications and Waiting
<?php
class My extends Thread {
    public function run() {
        /** cause this thread to wait **/
        $this->synchronized(function($thread){
            if (!$thread->done)
                $thread->wait();
        }, $this);
    }
}
$my = new My();
$my->start();
/** send notification to the waiting thread **/
$my->synchronized(function($thread){
    $thread->done = true;
    $thread->notify();
}, $my);
var_dump($my->join());
?>
The above example will output:
bool(true)