srand

(PHP 3, PHP 4 )

srand -- Seed the random number generator

Description

void srand ( int seed)

Seeds the random number generator with seed.

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

Замечание: Since PHP 4.2.0 it's no longer necessary to seed the random number generator before using it.

See also rand(), getrandmax() and mt_srand().