srand
srand
(PHP 4, PHP 5, PHP 7)
srand — Seed the random number generator
Description
void srand ([ int $seed ] )
Seeds the random number generator with seed or with a random value if no seed is given.
Note: There is no need to seed the random number generator with srand() or mt_srand() as this is done automatically.
Note: As of PHP 7.1.0, srand() has been made an alias of mt_srand().
Parameters
-
seed -
An arbitrary integer seed value.
Return Values
No value is returned.
Changelog
| Version | Description |
|---|---|
| 7.1.0 | srand() has been made an alias of mt_srand(). |
Examples
Example #1 srand() example
<?php
// seed with microseconds
function make_seed()
{
list($usec, $sec) = explode(' ', microtime());
return $sec + $usec * 1000000;
}
srand(make_seed());
$randval = rand();
?> See Also
- rand() - Generate a random integer
- getrandmax() - Show largest possible random value
- mt_srand() - Seeds the Mersenne Twister Random Number Generator
© 1997–2017 The PHP Documentation Group
Licensed under the Creative Commons Attribution License v3.0 or later.
https://secure.php.net/manual/en/function.srand.php
