PHP - Remove last character if it's a period?

Question

How to remove the last character only if it's a period?

$string = "something here.";
$output = 'something here';

Answer 1

$output = rtrim($string, '.');

Answer 2

using rtrim replaces all "." at the end, not just the last character

$string = "something here..";
echo preg_replace("/\.$/","",$string);