What is const pointer in c?

Answer:  

Constant pointer is pointer which points a fixed object. For example:

int i=10;

int * const p=&i;

Here p is constant pointer which is pointing to variable i. After the initialization statement pointer p cannot points any other variable. For example:

#include<stdio.h>

void main(){

    int i=10,j=20;

    int * const p=&i;

    p=&j  //cannot modify const pointer

    printf("%d",*p);

}

Output: Compilation error

But we can modify the content of any const pointer. For example:

#include<stdio.h>

void main(){

    int i=10;

    int * const p=&i;

    *p=25;

    printf("%d",i);

}

Output: 25