18. Editing C Code

This is a smart editing mode for C code. It knows a lot about C syntax and tries to position the cursor according to C layout conventions. You can change the details of the layout style with option variables.

The mode provides the following features:

• Expression and list commands understand all C brackets.
• Tab indents for C code.
• Comments are delimited with /* ... */.
• Paragraphs are separated by blank lines only.
• Delete converts tabs to spaces as it moves back.

The variables controlling indentation style are:

c-tab-always-indent

Non-nil means TAB in C mode should always reindent the current line, regardless of where in the line point is when the TAB command is used.

c-auto-newline

Non-nil means automatically newline before and after braces, and after colons and semicolons, inserted in C code.

c-indent-level

Indentation of C statements within surrounding block. The surrounding block's indentation is the indentation of the line on which the open-brace appears.

c-continued-statement-offset

Extra indentation given to a substatement, such as the then-clause of an if or body of a while.

c-continued-brace-offset

Extra indentation given to a brace that starts a substatement. This is in addition to c-continued-statement-offset.

c-brace-offset

Extra indentation for line if it starts with an open brace.

c-brace-imaginary-offset

An open brace following other text is treated as if it were this far to the right of the start of its line.

c-argdecl-indent

Indentation level of declarations of C function arguments.

c-label-offset

Extra indentation for line that is a label, or case or default.

NOTE: This package has been obsoleted by the cc-mode package (see section `Top' in CC Mode Manual). cc-mode can be quite slow, however, on large files, even on fast machines. This version works with no problems on the XEmacs source code and is very very fast.

To configure this package, type:

  M-x customize-group RET old-c RET