valid or invalid pointer

[sajis997]

Hello Forum,

How do we distinguish between the valid and invalid pointer ?

Check the following code

void func(int *i)
{
   if(i)
   {
       // does it mean that i is valid 
   }
}

So if we check for if(i != NULL) , does it mean that the pointer is valid ?

Any thoughts ?


Regards
Sajjadul

[cire]

So if we check for if(i != NULL) , does it mean that the pointer is valid ?

No. It means the pointer is not NULL. In general, there is no way to check if a pointer is "valid" so you should avoid situations where you have invalid pointers hanging around.

[keskiverto]

Semantically, the null pointer is the only pointer that with certainty is always "valid". Not the "safe to dereference" kind of valid though.