Null pointer Exception ( int Vs char)

Question

Program 1:

#include <iostream>
using namespace std;
int main ()
{
   int  *ptr = NULL;
   cout << "The value of ptr is " << ptr ;
   return 0;
}

Program 2:

#include <iostream>
using namespace std;
int main ()
{
   char  *ptr = NULL;
   cout << "The value of ptr is " << ptr ;
   return 0;
}

The question is,In the Program 1 the output is stable as :

  The value of ptr is 00000000

while,in the Program 2,instead of int pointer I used char pointer and it gives me an Exception.

can anyone help me with the understanding?

score 3 · Answer 1 · answered May 13 '16 at 04:34

3

Because the << operator isn't dereferencing the int* in the first program, it's simply printing the value of the pointer as 0. But in the second program the << operator is attempting to dereference the pointer as a string, which crashes.

answered May 13 '16 at 04:34

kcraigie

1,252
6
13

Can i avoid the de-referencing in the char pointer case? – Mukesh Pareek May 13 '16 at 04:36
@MukeshPareek see [this duplicate](https://stackoverflow.com/questions/10869459/char-pointer-confusing-with-cout-in-c). – WhozCraig May 13 '16 at 04:37
You can cast the char* as an int, like: (int)ptr – kcraigie May 13 '16 at 04:38
@WhozCraig Thank you for the link – Mukesh Pareek May 13 '16 at 04:42

Null pointer Exception ( int Vs char)

1 Answers1