In the firmware that I am writing, I created a type of variable. Similar to what is below:
struct SitemMenu {
unsigned int id;
char * text;
void * submenu
}
typedef struct SitemMenu TitemMenu;
Be any function:
void functionX () {
...
}
If I create this variable:
TitemMenu itemWhatever;
and do:
itemWhatever.submenu = &function (X);
Can I call functionX doing:
(*itemWhatever.submenu)();
I did something similar to this and the compiler give this answer:
error: (183) function or function pointer required
Yes you can, but not quite the way you've written it.
A function pointer is not declared in quite the same way as a 'normal' pointer.
What you need is:
struct SitemMenu {
unsigned int id;
char * text;
void (* submenu)(void); // this is a function pointer, as opposed to the 'normal' pointer above
};
typedef struct SitemMenu TitemMenu;
TitemMenu itemWhatever;
then, if you have some function declared with the same parameters and return type, like:
void functionX(void)
, then you can do:
itemWhatever.submenu = functionX;
itemWhatever.submenu();