What is the difference between static structure and normal structure?

Question

I have some sample code.

struct node { 
        int data;
        struct node *link;
    };
    static struct node *first = NULL;

It would be great if someone could talk about my bottom questions about using the word static.

• What does the static keyword do in the above code?

• What is the difference between normal structure and static structure?

Answer 1

It creates a static pointer to nodeand initializes it to NULL.

A variable definition can have several values:

static struct node *first = NULL;

If defined outside the method, it gives an first internal binding . It can only be used inside the defining module.

But you can also find this line inside the method:

void foo()
{ 
    static struct node *first = NULL;
}

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Answer 2

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extern struct node *first;

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Answer 3

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Answer 4

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Answer 5

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