Some issue with pointers


Hello,

I need some help to understand what I'm doing :)

I'm writing code for an embedded system and I need to create a navigable menu system. I'm going to use these structures:

typedef struct {
char *name[2];
int type;
int num_param;
void *ptr;
} menuitem_t;

typedef struct {
char *name[2];
int num_items;
menuitem_t *items;
} menu_t;


The latter defines each menu or submenu with a name, a number of items and a pointer to the items structure.

The former defines each menu item with a name, a type (see below) the number of parameters - if any - and finally a generic pointer (see below again).

In this way I can generate menus of any complexity and very flexible. The void pointer should point to another menu_t struct if the item leads to a submenu, to an array if it leads to a parameter list. But it could also leads to a function if the selection of this item needs an action to be executed.

Actually I have two questions:

1) I can't cast correctly the void *ptr. Let's say I want to access to:

char *par[] = {"First", "Second"};

ot invoke:

void myfunc();

Please, may you help me to understand how to cast and then to use that pointer in these cases?

2) It would be nice if I can know the path the user is following. For example:

mainmenu -> seconditem -> firstitem

where each of these entities are menu_t structs.
How would you implement such a dynamic path?

Thank you and I apologize for my poor English
Marco / iw2nzm
.

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