parallelize php process helper

parallelize.helper.php

<?php

function parallelize($func, $arr, $procs=4)
{
    //to work with collections
    //but you can also use chunk() n.f.
    $chunks   = $arr->chunk(ceil((count($arr) / $procs)));
    $pid      = -1;
    $children = array();
    foreach ($chunks as $items) {
        $pid = pcntl_fork();
        if ($pid === -1) {
            die('could not fork');
        } else if ($pid === 0) {
            // We are the child process. Pass a chunk of items to process.
            array_walk($items, $func);
            exit(0);
        } else {
            // We are the parent.
            $children[] = $pid;
        }
    }

    // Wait for children to finish.
    foreach ($children as $pid) {
        // We are still the parent.
        pcntl_waitpid($pid, $status);
    }
}