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<sqrttan>
Last updated: Thu, 26 Jun 2008

srand

(PHP 4, PHP 5)

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: As of PHP 4.2.0, there is no need to seed the random number generator with srand() or mt_srand() as this is now done automatically.

Parameters

seed

Optional seed value

ChangeLog

Version Description
Since 4.2.0 The seed becomes optional and defaults to a random value if omitted.

Examples

Example #1 srand() example

<?php
// seed with microseconds
function make_seed()
{
  list(
$usec, $sec) = explode(' ', microtime());
  return (float)
$sec + ((float) $usec * 100000);
}
srand(make_seed());
$randval = rand();
?>



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Seed the random number generator
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<sqrttan>
Last updated: Thu, 26 Jun 2008
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