Reliably detect if PHP script is running under IIS

Question

Because of the infamous IIS bugs concerning the "Location" redirect header, we have to use the "Refresh" header instead.

So, I would like to know the best method to programmatically detect if PHP script is running under IIS.

Currently used method is DIRECTORY_SEPARATOR !== '/', but obviously Apache and other servers under Windows are uncorrectly recognized as IIS.

I thought about:

strpos($_SERVER['SERVER_SOFTWARE'], 'Microsoft-IIS') !== false

... but this element corresponds to the "Server" header of the HTTP response, and it may have been removed by various means.

Any ideas of robuster methods?

Māris Kiseļovs · Accepted Answer · 2012-09-11 08:22:28Z

1

According to http://www.helicron.net/php/, IIS will leave $_SERVER['DOCUMENT_ROOT'] empty but apache will not.

answered Sep 11, 2012 at 8:22

Māris Kiseļovs

17.3k5 gold badges43 silver badges50 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

Gras Double Over a year ago

Yep, I had found this article too, but is this method safe enough? How do other servers than Apache and IIS behave? Do latest (and future) IIS versions still miss this element? Also, the article isn't dated but I guess it has been written for quite some time.

Māris Kiseļovs Over a year ago

I have no idea about that, but I would just go for simple variable in web-app configuration to define currently used web-server.

Collectives™ on Stack Overflow

Reliably detect if PHP script is running under IIS

1 Answer 1

2 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

2 Comments

Your Answer

Sign up or log in

Post as a guest

Related