What are common pitfalls when using a random code generator in PHP?

One common pitfall when using a random code generator in PHP is generating codes that are not truly random or unique, leading to potential security vulnerabilities. To solve this, it's important to use a secure random number generator function like `random_bytes()` or `openssl_random_pseudo_bytes()` to create unique and unpredictable codes.

// Generate a random code using a secure random number generator
function generateRandomCode($length = 8) {
    return bin2hex(random_bytes($length));
}

// Example usage
$randomCode = generateRandomCode(10);
echo $randomCode;