get valid random socket port with php

socket.port.php

<?php
//get valid random socket port with php

$s = stream_socket_server("tcp://localhost:0");

$ss = stream_socket_get_name($s,0);


$pos = 
strrpos($ss,":");

  $p =  substr($ss,$pos+1);

fclose($s);
//$p+=1;

echo "http://localhost:$p\n";

  
exec("php -S localhost:$p");

//var_dump($ss);