gen_mt_rand_data.php

<?php
// Quick script to get some not-cryptographically-secure random data
// to stdout in a portable way. Useful for generating uncompressable
// test files

define("INTS_PER_LOOP", 4096);

$f = str_repeat("l", INTS_PER_LOOP);
$r = []; // Using SplFixedArray is actually slower

mt_srand(random_int(PHP_INT_MIN, PHP_INT_MAX));

while (true) {
  for ($i = 0; $i < INTS_PER_LOOP; $i++) {
    $r[$i] = mt_rand();
  }
  echo pack($f, ...$r);
}