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Recommended C Style and Coding Standards

File Organization

• file consists of various sections that should be separated by several blank lines
• although there are no limit files with more than 1000 lines are cumbersome to deal with
• lines longer than 79 columns are not handled well by all terminals and should be avoided if possible
• avoid deep indenting

File Naming Conventions

File names are made up of a base name, and an optional period and suffix.

• base name should be eight or fewer characters
• suffix should be three or fewer characters

Program Files

The suggested order of sections for a program file is as follows

1. Prologue that tells what is in that file
   1. Description of the purpose of the objects in the files (whether they be functions, external data declarations or definitions, or something else) is more useful than a list of the object names
   2. may contain author(s), revision control information references, etc.
2. Any header file includes
   1. if the include is for a non-obvious reason, the reason should be commented
   2. system include files like <stdio.h> before user include files
3. Any defines and typedefs that apply as a whole.
   1. In order of
      1. Constant macro
      2. function macro
      3. typedefs and enums
4. Global (external) data declarations
   1. In order of
      1. externs
      2. non-static globals
      3. static globals
   2. If a set of defines applies to a particular piece of global data (such as a flags word), the defines should be immediately after the data declaration, indented to put the defines one level deeper than the first keyword of the declaration to which they apply. (norminette not allowed)
5. Functions
   1. should be in some meaningful order (ex. like functions should appear together)
   2. A “breadth-first” approach (functions on a similar level of abstraction together) is preferred over depth-first (functions defined as soon as possible before or after their calls). Considerable judgement is called for here. (your decision)
   3. If defining large numbers of essentially-independent utility functions, consider alphabetical order