Why do we pass the link when we have the choice to make the variable external?

Question

Suppose we have an array:

int arr[1000];

and I have a function that works in this array:

void Func(void);

Why is it ever necessary to pass by reference (by changing the void) when I can have arr [1000] as an external variable outside main ()?

• What is the difference? Is there any difference?
• Why do people prefer to follow the link rather than make it external? (I myself think that making it external is easier).

Answer 1

I think you are asking if global variables are . Quoting a great answer :

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Answer 7

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Answer 8

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Answer 9

This is also a maintenance problem. Why do I want to track some external somewhere when I can just look at a function and see what it should be?