Re: Avoiding dangling pointers.

In article
<bde62ae2-6cbb-4e33-a03a-204c5f7e320b@[EMAIL PROTECTED]
>,
Rafael Anschau <rafael.anschau@[EMAIL PROTECTED]
> wrote:

> I read that you should assign null (0) to all pointers that you call
> delete on.
> 
> Does that mean:
> 
> *p=0(set the value pointed to to 0).
> 
> or
> 
> p=0(set the address held to zero).
> 
> The last one is awkward for none would want a pointer pointing
> to address zero(even though it compiles fine, you can´t assign
> anything to it).
> 
   assuming you mean
    a)  delete p; *p = 0;  // undefined behavior
or
    b)  delete p;p=0;  // fine as far as it goes.
b stores 0 in p, not where p points therefore it is defined and makes p
a null pointer, so that it can be tested to see if if points anywhere
with an ordinary if(p)  { /* p points somewhere */} else {/*  it
doesn't*/}

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