A8 - functions

type FunctionName(type parameter1, type parameter2, ...) /* function type is the type returned by it */
{
	... ;
	return value;
}

FunctionName(parameter); /* invokation */

• allows reusing of code
• note that variables scope is only within the function block

float CelciusFromFahrenheit(float tempF)
{
	float tempC = (tempF - 32.0) * 5.0 / 9.0;
	
	return tempC;
}

float tempC = CelciusFromFahrenheit(tempF);

• main is the most important function, which is the entry point of a program
• the return value is the exit code

void Swap (int *a, int *b) /* accepts pointers */
{
	int tmp = *a;
	*a = *b;
	*b = tmp;
}

int a = 10; int b = 20;
Swap(&a, &b); /* passing references */
printf(a, b)

• note that to the pointer references should be passed if the variable value needs to be changed outside the function