Question

I need to store a pointer to a char array in a struct, and then modify/access the arrays content. How can I do that?

I can only think of something similar to this, but I don’t get to the complete compilable solution.

struct foo {
    unsigned char *array;
};

And then:

unsigned char array[512];
struct foo *foo;
foo->array = array;

In another function which receivers pointer to struct:

*(foo->array[0]) = 'K';

Answer 1

Your code is almost fine:

foo->array[0] = 'K';

The problem with your code *(foo->array[0]) is that you try to dereference a char which is not even a pointer.

You also need to allocate memory for the struct – currently foo points to some random memory location where an access will most likely crash your program:

struct foo *foo = malloc(sizeof(*foo));