What text editor under OS X can close current window when you press ESC key? I'm looking for a text editor that can close the current file when you press ESC key. 

I am interested about this for using with a file manager, I open for edit a file and with ESC I want to return to the file commander.

I tried to override the close window command on XCode but it didn't work, instead of closing the window it does write me an upside down question mark!?

In addition, I tried to assign ESC as shortcut key in System Preferences, but this is not allowed.
Emacs allows you to override shortcuts keys.

Add this line to your .emacs file (located in your home directory) :  

(global-set-key (kbd "&lt;escape&gt;") 'save-buffers-kill-emacs)