Xdebug in a nutshell

PHP registers handlers for:

Mime types:

• application/x-httpd-php

• application/x-httpd-php-source

Others:

• text/html (Apache xbithack)

• php-script (Apache 2)

On a request, Apache:

• checks for the MIME type handler

• opens the file

• fills a meta data record

• hands PHP a filepointer