Is there any restriction for declaring a pointer variable p1 which holds the address of another pointer variable p2 and so on.

Question

ex:
int a,*p=&a;
int **p1=&p;
int ***p3=&p1; // so on...
.
.
.

Answer 1

No restrictions. This is used regularly when you want to "pass" a pointer to some function. Basically you provide "p1" so function can change "p".