(PECL pthreads >= 3.0.0)
Worker::collect — Collect references to completed tasks
Allows the worker to collect references determined to be garbage by the optionally given collector.
collectorA Callable collector that returns a boolean on whether the task can be collected or not. Only in rare cases should a custom collector need to be used.
The number of remaining tasks on the worker's stack to be collected.
Example #1 A basic example of Worker::collect()
<?php
$worker = new Worker();
echo "There are currently {$worker->collect()} tasks on the stack to be collected\n";
for ($i = 0; $i < 15; ++$i) {
$worker->stack(new class extends Threaded {});
}
echo "There are {$worker->collect()} tasks remaining on the stack to be collected\n";
$worker->start();
while ($worker->collect()); // blocks until all tasks have finished executing
echo "There are now {$worker->collect()} tasks on the stack to be collected\n";
$worker->shutdown();
以上例程会输出：
There are currently 0 tasks on the stack to be collected There are 15 tasks remaining on the stack to be collected There are now 0 tasks on the stack to be collected