Pointer to pointer(**) in C

Learn about C Program to use Pointer to pointer(**) in the below code example. Also refer the comments in the code snippet to get a detailed view about what’s actually happening.

C Program to use Pointer to pointer(**):

A pointer is used to store the address of a variable. Similarly, we must use ** to hold the address of a pointer (pointer to pointer). ** A pointer that holds the address of another pointer.

** is used to print the value contained in the pointer to pointer variable.

#include <stdio.h>

int main()
{
	char ch = 'a'; // create a variable
	char *ptr = &ch; // create a pointer to store the address of ch
	char **ptrToPtr = &ptr; // create a pointer to store the address of ch

	printf("Address of ch: %p\n", &ch); // prints address of ch
	printf("Value of ch: %c\n", ch);  // prints 'a'

	printf("\nValue of ptr: %p\n", ptr);  // prints the address of ch
	printf("Address of ptr: %p\n", &ptr); // prints address

	printf("\nValue of ptrToPtr: %p\n", ptrToPtr);  // prints the address of ptr
	printf("*ptrToPtr(Address of ch): %p\n", *ptrToPtr);  // prints the address of ch
	printf("**ptrToPtr(Value of ch): %c\n", **ptrToPtr);  // prints ch
}

Output:

Address of ch: 000000000061FE17
Value of ch: a

Value of ptr: 000000000061FE17
Address of ptr: 000000000061FE08

Value of ptrToPtr: 000000000061FE08
*ptrToPtr(Address of ch): 000000000061FE17
**ptrToPtr(Value of ch): a

Hope above code works for you and Refer the below Related Codes to gain more insights. Happy coding and come back again.

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