php: empty line from nowhere
debugging, php
Solution
Almost always, there will be an empty line before or after your `<?php ?>` tags. If not in your main file, look at your includes.
Also, a little tip... if your file is pure PHP, just start it with `<?php` and never close the PHP tag. Closing it isn't necessary, and then you avoid blank lines at the end causing you trouble.
Problem
I have strange error and not sure how to tackle it without wasting too much time. I have a method in my controller which should return xml using: ``` header("Content-type: text/xml"); header("Content-Disposition: attachment; filename=output.xml"); header("Pragma: no-cache"); header("Expires: 0"); ``` the thing is that the output is not valid xml because of empty line and I have no idea from where it comes, do you have an idea how to fix this? maybe ignore this empty line or something? I do not want to debug the whole framework... I tried to use `var_dump(debug_backtrace())` but I get one big mess probably because of doctrine.