Where is $scripturl defined?

[JamesWC]

I want to rename index.php to forum.php, and as there doesn't appear to be a friendly setting for this (like there is for changing the filepath), I assume I'll need to edit the line of code that defines $scripturl - but where is this line of code?

Thanks to anyone who can point me to the relevant file!

(I'm using SMF 2.0.2.)

[Adrek]

http://www.simplemachines.org/community/index.php?topic=58439.0
works fine with 2.0.2

[JamesWC]

Perfect, thanks phantomm!