Cosmos Guides

Your personal library of every algorithm and data structures code that you will ever encounter

C Code style

C is a general-purpose mid level, procedural computer programming language originally developed between 1969 and 1973 and founded by Dennis Ritchie in AT&T Labs in 1972.

C Programming Style Guide

This code style is known as Kernel Normal Form (KNF).

Index

• Braces
• Indentation
• Conditionals
• Functions
• Comments

Braces

All braces should go on the same line as whatever the braces are delimiting, with the only exception being functions. For if/else statements, braces should only be used as required.

int
main(int argc, char *argv[])
{
	if (!some_function()) {
		puts("Something happened!");
		do_a_thing();
	} 
	else
	{
		some_other_thing();
        }
	return (0);
}

*argc stands for arguments count(ARGument count) *argv stands for arguments values(ARGument values) *argv[0] is the name of the program

Indentation

Indentation is done with a single tab character (Hard Tab). For code split across multiple lines a helper indent of 4 spaces is used.

int
some_really_long_function(int a, int b, int c, int d,
    int e, int f)
{
	do_something();

Conditionals

if (a == 9) {

for (;;)

Each case in a switch statement should not be indented but the code for each should be. Any case fallthroughs should be commented. Every case should be terminated with a break statement.

switch (ch) {
case 'a':
	a_count++;
	/* FALLTHROUGH */
case 'b':
	do_something();
	break;
case 'c'
	other_thing();
	break;
default:
	def_thing();
}

Functions

Functions should have the type on a seperate line proceeding the rest of the function definition.

int
main(int argc, char *argv[])
{
//Block of Code
//" " "
//" " "
}

Return statements should have the value wrapped in parenthesis.

return (0);

Comments

Always use C style comments (/* */) and not C++ style comments (//). A sample is shown below.

/* One line comment */ 

/*
 * Multiline comment. Fill it out like it were
 * a paragraph.
 */