Go language pointer to pointer

If a pointer variable holds the address of another pointer variable, the pointer variable is called a pointer variable that points to the pointer.

When defining a pointer variable that points to a pointer, the first pointerstores the address of the second pointer, and the second pointer stores theaddress of the variable:

The pointer variable declaration to the pointer is in the following format:

var ptr **int;

The pointer variable to the pointer above is an integer.

Accessing the value of a pointer variable pointing to a pointer requires theuse of two * number, as follows:

package main

import "fmt"

func main() {

   var a int
   var ptr *int
   var pptr **int

   a = 3000

   /* Pointer ptr address */
   ptr = &a

   /* Pointing to pointer ptr address */
   pptr = &ptr

   /* Obtain the value of pptr */
   fmt.Printf("Variable a= %d\n", a )
   fmt.Printf("Pointer variable * ptr = %d\n", *ptr )
   fmt.Printf("Pointer variable pointing to a pointer **pptr = %d\n", **pptr)
}

The output of the above example is as follows:

Variable a= 3000
pointer variable *ptr = 3000
Pointer variable pointing to a pointer **pptr = 3000