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Library cc-mode
Command c-mode
Builtin yes
Auto-activates for *.c *.h *.xbm *.xpm *.y *.yacc *.lex *.i *.m

c-mode is the default major mode for editing C source files. Its major features are customizable indentation and font-locking (coloring of code).

Basic setup

c-mode is bundled with Emacs by default. No additional setup is required.

Helpful keybindings

Go to the beginning of the current function. If you are between 2 functions, go the start of the previous one.
Go to the end of the current function. If you are between 2 functions, go to the end of the next one.
Mark current function
Go to beginning of current statement (or next one).
Go to end of current statement (or previous one).

Common Customization


Any mode based on cc-mode provides automatic indentation. The default style is gnu. It is the one recommended by the Free Software Foundation for GNU projects but you can use a different one.

Here is a basic list of predefined styles:

The default style for GNU projects
What Kernighan and Ritchie, the authors of C used in their book
What BSD developers use, aka “Allman style” after Eric Allman.
Popularized by the examples that came with Whitesmiths C, an early commercial C compiler.
What Stroustrup, the author of C++ used in his book
Popular C++ coding standards as defined by “Programming in C++, Rules and Recommendations,” Erik Nyquist and Mats Henricson, Ellemtel
What the Linux developers use for kernel development
What Python developers use for extension modules
The default style for java-mode (see below)
When you want to define your own style

You can look the cc-mode documentation for a complete list of builtin style. For visual example of each style you can look the Wikipedia article on indenting style.

  • The default style is set via the variable c-default-style
  • Use [C-c .] (or M-x c-set-style) to change the indentation style of the current buffer.
  • The amount of space use to indent is set via the variable c-basic-offset.

To set the default style to K&R and use 4 spaces, add this to your Emacs configuration file:

; set k&r style
(setq c-default-style "k&r")
; indent with 4 spaces
(setq c-basic-offset 4)






Recommended Reading

Project Pages

Tutorial Pages

See also

Ebrowse, a C++ class browser