gmp_random

(PHP 4 >= 4.0.4, PHP 5, PHP 7)

gmp_random — Random number

Warning

This function has been DEPRECATED as of PHP 7.2.0, and REMOVED as of PHP 8.0.0. Relying on this function is highly discouraged.

Description

function gmp_random(int $limiter = 20): GMP

Generate a random number. The number will be between 0 and (2 ** n) - 1, where n is the number of bits per limb multiplied by limiter. If limiter is negative, negative numbers are generated.

A limb is an internal GMP mechanism. The number of bits in a limb is not static, and can vary from system to system. Generally, the number of bits in a limb is either 32 or 64, but this is not guaranteed.

Caution

This function does not generate cryptographically secure values, and must not be used for cryptographic purposes, or purposes that require returned values to be unguessable.

If cryptographically secure randomness is required, the Random\Randomizer may be used with the Random\Engine\Secure engine. For simple use cases, the random_int() and random_bytes() functions provide a convenient and secure API that is backed by the operating system’s CSPRNG.

Parameters

limiter

The limiter.

A GMP object, an int, or a string that can be interpreted as a number following the same logic as if the string was used in gmp_init() with automatic base detection (i.e. when base is equal to 0).

Return Values

A random GMP number.

Examples

Example #1 gmp_random() example

<?php
$rand1 = gmp_random(1); // random number from 0 to 1 * bits per limb
$rand2 = gmp_random(2); // random number from 0 to 2 * bits per limb

echo gmp_strval($rand1) . "\n";
echo gmp_strval($rand2) . "\n";
?>

The above example will output:

1915834968
8642564075890328087