Add command to make Emacs window fullscreen.

Default keybinding is F11. The command follows freedesktop standards,
so it should work on most desktops, at least in GNU/Linux systems.

README.md

@@ -205,6 +205,7 @@ Keybinding         | Description
 <kbd>C-h A</kbd>   | Run `apropos` (search in all Emacs symbols).
 <kbd>M-/</kbd>     | Run `hippie-expand` (a replacement for the default `dabbrev-expand`).
 <kbd>C-x C-b</kbd> | Open `ibuffer` (a replacement for the default `buffer-list`).
+<kbd>F11</kbd>     | Make the window full screen.
 <kbd>F12</kbd>     | Toggle the Emacs menu bar.
 <kbd>C-x g</kbd>   | Open Magit's status buffer.
 <kbd>C-=</kbd>     | Run `expand-region` (incremental text selection).

core/prelude-core.el

@@ -514,5 +514,13 @@ With numeric prefix arg DEC, decrement the integer by DEC amount."
   (interactive "p")
   (prelude-increment-integer-at-point (- (or dec 1))))
 
+(defun prelude-fullscreen ()
+  "Makes Emacs window fullscreen.
+
+This follows freedesktop standards."
+  (interactive)
+  (x-send-client-message nil 0 nil "_NET_WM_STATE" 32
+                         '(2 "_NET_WM_STATE_FULLSCREEN" 0)))
+
 (provide 'prelude-core)
 ;;; prelude-core.el ends here

core/prelude-global-keybindings.el

@@ -96,6 +96,9 @@
 ;; replace buffer-menu with ibuffer
 (global-set-key (kbd "C-x C-b") 'ibuffer)
 
+;; make window fullscreen
+(global-set-key (kbd "<f11>") 'prelude-fullscreen)
+
 ;; toggle menu-bar visibility
 (global-set-key (kbd "<f12>") 'menu-bar-mode)