void (*p[10]) (void (*)());

p is an "array of 10 pointers to a function returning void and taking a pointer to another function that returns void and takes no arguments." The cumbersome syntax is nearly indecipherable, isn't it? You can simplify this declaration considerably by using typedefs. First, declare a typedef for "pointer to a function returning void and taking no arguments" as follows:

typedef void (*pfv)();

Next, declare another typedef for "pointer to a function returning void and taking a pfv":

typedef void (*pf_taking_pfv) (pfv);

Now declaring an array of 10 such pointers is a breeze:

pf_taking_pfv p[10]; /*equivalent to 
void (*p[10]) (void (*)()); but much more readable*/