What is the purpose of the first “node” in the declaration: “typedef struct node { - - - } Node;”?

Question

I am studying code examples from my professor in order to become better acquainted with linked data structures.

In our linked-list.c example the professor defines a

Answer 1

The lower case 'node' is a structure type... i.e. a struct node { stuff } is a node structure containing stuff.

On the other hand, the upper case "Node" is a completely new data type which refers to a 'struct node'

Generally (though in C++ I think you can), you cannot pass around a "node" in a C program... for example as an argument to a function. Rather, you would have to pass a 'struct node' as your argument...

// this will throw a syntax error because "node" is not a data type, 
// it's a structure type.

void myFunc( node* arg ); 

// while this will not because we're telling the compiler we're 
// passing a struct of node

void myFunc( struct node* arg ); 

// On the other hand, you *can* use the typedef shorthand to declare 
// passing a pointer to a custom data type that has been defined 
// as 'struct node'

void myFunc( Node* arg );