selecting one random number every day

[ketanco]

for the following:
<img align="left" src="http://www...............com/pictures/software_small1.jpg">

I want to select a different picture each day randoly. my pictures are numbered as xxxxxxx_small1, xxxxxx_small2, xxxxx_small3 and so on....

I know how to write a random code for the number at the end. hwever, how can I make that random number change only once each day so that I show only one picture for one day?

What I thought doing was, selecting a random number exactly at 12:00 each day, and then selecting a new one ONLY IF 24 hours has passed...is my thinnking correct? if so how can I do it?

[djjjozsi]

you can save the image number in a file daily (cron job would be a better way)

<?php
$number=1;
?>

and include this file in your program. cron job then save the new image number with this php code.

$out='<?php
$number='. $random_number .';
?>
';
file_put_contents("randomimage.php" , $out);