PHP: How to generate a random, unique, alphanumeric string for use in a secret link?

Question

How would it be possible to generate a random, unique string using numbers and letters for use in a verify link? Like when you create an account on a website, and it sends y

Answer 1

Simplifying Scotts code above by removing unnecessary loops which is slowing down badly and does not make it any more secure than calling openssl_random_pseudo_bytes just once

function crypto_rand_secure($min, $max)
{
 $range = $max - $min;
 if ($range < 1) return $min; // not so random...
 $log = ceil(log($range, 2));
 $bytes = (int) ($log / 8) + 1; // length in bytes
 $rnd = hexdec(bin2hex(openssl_random_pseudo_bytes($bytes)));
 return $min + $rnd%$range;
}

function getToken($length)
{
 return bin2hex(openssl_random_pseudo_bytes($length)
}