Imagine the innermost is function pointer.

Only real Three Star Programmers can handle this amount of indirection

In C, if you want to let a function change a variable (let’s call it x), you need to pass it a pointer to x.

If x is a pointer to a pointer (**), in order to let a function edit x, you need to pass it to a pointer to x (in that case, a pointer to a pointer to a pointer ***).

yo dawg