c - Pointer to pointer to nested structure -

there 2 structures bst

typedef struct _price {     double price;     char* shopname; } pricing;  typedef struct _bstnode {     int id;     pricing** pl;     int nr_of_prices;     struct _bstnode *left;     struct _bstnode *right;     struct _bstnode *parent; } bstnode; 

i need make function can add , update price , shop name in bst node. 1 node may contain many shops , prices

void updateprice(bstnode* root, int id, char* shop, double price){ //to } 

i can add single shop name , price how add several objects?

(*(root->pl))=malloc(sizeof (pricing));  // ---?? (*(root->pl))->price=price; (*(root->pl))->shopname=shop; 

if nr_of_prices belongs pl, add dynamically 1 object:

int oldidx = root->nr_of_prices++; root->pl = realloc( root->pl, root->nr_of_prices * sizeof(*root->pl)); root->pl[oldidx] = malloc(sizeof(pricing)); root->pl[oldidx]->price = price; root->pl[oldidx]->shopname = shop;