在配置emacs的时候，一直想区别对待x-window和terminal两种环境。上周五配的nxhtml时，因为mumamo会给同一个buffer中的不同模式加上背景色，而我一般以终端方式使用emacs，所以当然希望背景全是黑的。
(custom-set-faces
;; custom-set-faces was added by Custom.
;; If you edit it by hand, you could mess it up, so be careful.
;; Your init file should contain only one such instance.
;; If there is more than one, they won’t work right.‘(mumamo-background-chunk-major ((((class color) (min-colors 8)) (:background “black”))))
‘(mumamo-background-chunk-submode1 ((((class color) (min-colors 8)) (:background “black”))))
‘(mumamo-background-chunk-submode2 ((((class color) (min-colors 8)) (:background “black”))))
‘(mumamo-background-chunk-submode3 ((((class color) (min-colors 8)) (:background “black”))))
‘(mumamo-background-chunk-submode4 ((((class color) (min-colors 8)) (:background “black”)))))
这时候，情况出现了。使用GUI方式时同一buffer的不同模式的背景是黑色，但和GUI默认的代码高亮方案冲突了，所以代码基本没法看。而terminal下面又表现的近乎完美，所以才有想区别对待x-window和terminal两种情况。翻遍emacs lisp才找到原来有个系统变量window-system，那么接下来的事情就好办了，为x-window装一个配色解决方案：color-theme：
;; color theme
(if (eq window-system ‘x)
(progn
(setq default-font “DejaVu Sans Mono”)
(add-to-list ‘load-path “/share/.emacs.d/color-theme-6.6.0″)
(require ‘color-theme)
(eval-after-load “color-theme”
‘(progn
(color-theme-initialize)
(color-theme-hober)))))
下面是emacs lisp手册中的原文描述：
Window Systems
Emacs works with several window systems, most notably the X Window System. Both Emacs and X use the term “window”, but use it differently. An Emacs frame is a single window as far as X is concerned; the individual Emacs windows are not known to X at all.topVariable: window-system
This variable tells Lisp programs what window system Emacs is running under. The possible values arex
Emacs is displaying using X.
pc
Emacs is displaying using MSDOS.
w32
Emacs is displaying using Windows NT or Windows 95.
nil
Emacs is using a character-based terminal.
这下就完美了！！！