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From: KOFKS on 21 Feb 2006 02:02
I come acorss a question about NULL, so I write a piece to verify my
opinion, but I'm cofused at the result.(Under dev-c++4.9.9.2, and I
have not tried other compiler.)
**********************************************************************
#include <iostream>
using namespace std;

int main()
{
void *p;
p = '\0';
if (NULL == p)
cout << " After \"p = \'\\0\';\" p is NULL " << endl;
p = 0;
if (NULL == p)
cout << " After \"p = 0;\" p is NULL " << endl;
p = (void *)EOF; //if remove (void*), compiler reports "invalid
conversion from 'int' to 'void'.
if (NULL == p)
cout << " After \"p = (void *)EOF;\" p is NULL " << endl;
p = NULL;
if (NULL == p)
cout << " After \"p = NULL;\" p is NULL " << endl;

system("pause");
return 0;
}
***********************************************************************
The output is :
***********************************************************************
After "p = '\0';" p is NULL
After "p = 0;" p is NULL
After "p = NULL;" p is NULL
***********************************************************************
So why? I used to believe EOF is NULL, however it seems wrong.

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