Check if PHP is installed on Apache or IIS Server?

Question

Is there a way to check if PHP is installed on an Apache or IIS server within the PHP environment itself?

If so, how?

Answer 1

You can also find out via the $_SERVER['DOCUMENT_ROOT'], sort of:

Read http://www.helicron.net/php/

(Basically, according to the article, Apache sets the document root with a valid variable, and IIS does not).