C Pointer Logic

Question

I have a pointer to a struct that contains a pointer to a short value. The following is the struct.

typedef struct {
  short *val;
} x;

If I have a pointer to a variable of type x, I can dereference it and access an element of the struct by doing x->val, but since val is a pointer as well, this only gives me the adress of val. How can I dereference this to access the value of val? I tried *(x->val), but that is not working. Or should it work like this, and my mistake has to be something entirely different?

Answer 1

It seems you are using the structure name in this expression

*(x->val)

Instead you need to use a pointer to an object of the structure type. For example

#include <stdio.h>

typedef struct {
  short *val;
} x;

int main( void )
{
    short value = 10;
    x obj = { .val = &value };
    x *p = &obj;

    printf( "%d\n", *p->val );
}