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srand

(PHP 3, PHP 4 , PHP 5)

srand -- Seed the random number generator

Description

void srand ( [int seed])

Seeds the random number generator with seed. Since PHP 4.2.0, the seed becomes optional and defaults to a random value if omitted.

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();
?>

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.

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

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olor="#0000BB">$db, "INSERT INTO strings VALUES ('$str')");
}

function max_len_step(&$context, $string)
{
    $string = sqlite_udf_decode_binary($string);
    if (strlen($string) > $context) {
        $context = strlen($string);
    }
}

function max_len_finalize(&$context)
{
    return $context;
}

sqlite_create_aggregate($db, 'max_len', 'max_len_step', 'max_len_finalize');

var_dump(sqlite_array_query($db, 'SELECT max_len(a) from strings'));

?>