#include
int main()
{
int *p = NULL;if (p == NULL)
{
printf (“p is NULL\n”);
}
else
{
printf (“p is not NULL\n”);}
}
Above produce below result :
[hchiramm@humbles-lap ]$ ./a.out
p is NULL
But, if we have below code :
#include
int main()
{
int *p = NULL;
if (p)
{
printf (“p is NULL\n”);
}
else
{
printf (“p is not NULL\n”);}
}
[hchiramm@humbles-lap ]$ ./a.out
p is not NULL
Because NULL is represented as binary zero in a system, that said, binary zero is treated as “false” in C, so else clause is getting executed..
In standard libike this:
#define NULL ((void*)0)
Dereferencing a NULL pointer will result in ‘segmentation fault” .