C struct, pointers

Question

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C : pointer to struct in the struct definition

In my beginer course we need to declare a struct for tree search. I need pointers for reference of same type in each node. This decleration seems incorrect, pnode is not known in this context. How can i archieve my goal?

typedef struct 
{ 
    int value;
    int right;
    int left;
    pnode nextleft;
    pnode nextright;
}node, *pnode;

score 2 · Answer 1 · answered Dec 21 '11 at 20:22

the C Faq is a good reference. http://c-faq.com/struct/selfref.html

I tend to use the typedef before the struct method

http://c-faq.com/decl/selfrefstruct.html

   typedef struct a *APTR;
    typedef struct b *BPTR;

    struct a {
        int afield;
        BPTR bpointer;
    };

    struct b {
        int bfield;
        APTR apointer;
    };

score 1 · Accepted Answer · answered Dec 21 '11 at 20:20

1

struct node
{
    int value;
    int right;
    int left;
    struct node *nextleft;
    struct node *nextright;
};

Here, node is within the tag namespace.

answered Dec 21 '11 at 20:20

dreamlax

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+1 And if you want to avoid having to use `struct node` and `struct node *` to declare instances of your structure, you can still add `typedef struct node node; typedef struct node* pnode;` after the structure definition. Although for code clarity, I would prefer not to. – JoeFish Dec 21 '11 at 20:24

C struct, pointers

2 Answers2