I'm currently working on using the crouton xiwi X windows target to run an Emacs session on a Chromebook. I've done this by starting Emacs as the last entry in .xinitrc making it effectively the window manager for the session. Despite having the frame configured to be fullsize it's not using the full width of the display (which can be resized dynamically).
Is there native support in Emacs for querying the host X session display size or do I need to resort to shell script calls to extract the data?