www.delorie.com/gnu/docs/emacs/cc-mode_21.html

search

	Buy the book!

CC Mode Manual

7.2 Permanent Customization

To make your changes permanent, you need to add some lisp code to your `.emacs' file. CC Mode supports many different ways to be configured, from the straightforward way by setting variables globally in `.emacs' or in the Customization interface, to the complex and precisely controlled way by using styles and hook functions.

The simplest way of customizing CC Mode permanently is to set the variables in your `.emacs' with setq and similar commands. So to make the setting of substatement-open permanent, add this to the `.emacs' file:

(require 'cc-mode) (c-set-offset 'substatement-open 0)

The require line is only needed once in the beginning to make sure CC Mode is loaded so that the c-set-offset function is defined.

You can also use the more user friendly Customization interface, but this manual does not cover how that works.

Variables set like this at the top level in `.emacs' take effect in all CC Mode buffers, regardless of language. The indentation style related variables, e.g. c-basic-offset, that you don't set this way get their value from the style system (see section 7.4 Styles), and they therefore depend on the setting of c-default-style. Note that if you use Customize, this means that the greyed-out default values presented there might not be the ones you actually get, since the actual values depend on the style, which may very well be different for different languages.

If you want to make more advanced configurations, e.g. language-specific customization, global variable settings isn't enough. For that you can use the language hooks, see 7.3 Hooks, and/or the style system, see 7.4 Styles.

By default, all style variables are global, so that every buffer will share the same style settings. This is fine if you primarily edit one style of code, but if you edit several languages and want to use different styles for them, you need finer control by making the style variables buffer local. The recommended way to do this is to set the variable c-style-variables-are-local-p to t. The variables will be made buffer local when CC Mode is activated in a buffer for the first time in the Emacs session. Note that once the style variables are made buffer local, they cannot be made global again, without restarting Emacs.