Scope

Before getting into pointers, just know that what’s inside of a function stays in a function. Data inside of one’s scope cannot be accessed by other functions (unless we return the value, or declare the variable in the global scope - outside of every method).

Global variables are in the global scope. Local variables are in the local scope

Example of a local scope includes:

• Any code within the {} curly brace delimiters are inside its own scope.
• Functions
• Conditional statements

There’s only one example of the global scope. It’s the area where your #includes are; it’s outside of everything

#include <stdio.h>
// 
// 

int x; // Global scope

// // void say_hi() { int y; // Local scope }

Global variables

Can be accessed by any function

#include<stdio.h>
int global_int = 5;
// Global vars are stored for the entire program
 
int main(void)
{
	printf("%d%", global_int);
}

Somewhere else in memory are global things stored. Not in any specific function (kind of like when allocating memory dynamically)

Downside of global vars:

• for long programs, you can lose track of how the var is being changed.
• local vars are easier to debug.
• So we try to avoid them.

Uses

• Having some data that all sorts of methods will need to affect. (i.e. an image)
• Writing bad code