Re: segfault on strtok

From: Al Bowers (xabowers_at_rapidsys.com)
Date: 10/24/03 

Date: Fri, 24 Oct 2003 09:22:40 -0400

Andreas Kahari wrote:
> In article <3F9912C6.1399@mindspring.com>, pete wrote:
>
>>Andreas Kahari wrote:
>>
>>
>>>Yes, the integer zero is a null pointer, but only if it's cast
>>>to void * and converted into a pointer type.
>>
>>A constant expression with a value of zero,
>>is called a "null pointer constant"
>>(you can find that phrase in the standard),
>>whther or not it's cast to (void*).
>
>
> I was looking at the standard when I wrote it. It says that an
> integer which is zero is a null pointer constant if cast to void *.
> That null pointer constant is a null pointer if converted to
> a pointer type.
>

I believe what you are referring to in the standard is the
section 6.3.2.3 Pointers.
Paragraph:
3. An integer constant expression with the value 0, or such an
    expression cast to type void *, is called a null pointer constant.

Notice the word "or". It does not say "only if cast".
Among other posibilities, NULL may be defined as:
0, 0L, 0LL, or (void *)0. 

---
Al Bowers
Tampa, Fl USA
mailto: xabowers@myrapidsys.com (remove the x to send email)
http://www.geocities.com/abowers822/

Relevant Pages

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