Dereference a pointer inside a structure pointer

Question

I have a structure:

struct mystruct {     int* pointer; };  structure mystruct* struct_inst; 

Now I want to change the value pointed to by struct_inst->pointer. How can I do that?

EDIT

I didn't write it, but pointer already points to an area of memory allocated with malloc.

Answer 1

As with any pointer. To change the address it points to:

struct_inst->pointer = &var;

To change the value at the address to which it points:

*(struct_inst->pointer) = var;