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I defined a structure as follows:
typedef struct myStruct{
char *val1;
char *val2;
struct myStruct *prev;
struct myStruct *next;
} myStruct;
I also wrote a function to add a node to this structure:
void add_to_struct(struct myStruct *strct, char *val1,
char *val2){
// create the node for new element
struct myStruct *my_new = malloc(sizeof(struct myStruct));
my_new->val1 = val1;
my_new->val2 = val2;
my_new->next = strct;
my_new->prev = NULL;
strct->prev = my_new;
}
Adding a node to the struct using this function doesn’t seem to work though. I guess the problem is that I do not pass my structure (which I defined as a global variable) by reference correctly, but I don’t know why. Any idea what I am doing wrong?
EDIT How I call it:
void main(){
struct myStruct *headPrev = Malloc(sizeof(struct myStruct *));
struct myStruct *headNext = Malloc(sizeof(struct myStruct *));
char *headval1 = Malloc(sizeof(char) * MAXLEN);
char *headval2 = Malloc(sizeof(char) * MAXLEN);
my_struct = Malloc(sizeof(struct myStruct));
my_struct->prev = headPrev;
my_struct->next = headNext;
my_struct->val1 = headval1;
my_struct->val2 = headval2;
newVal1 = "abcd";
newVal2 = "bl";
....
add_to_struct(my_struct,newVal1,newVal2);
}
Answer
looks pretty close, just a few minor issues —
my_new should be allocated to be sizeof(struct myStruct)), not cacheElement, no?
also, this looks like a linked list, but you need to return my_new so you can use it as the new head of list.
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