Re: Antwort: Re: Antwort: Re: -EFAULT during freeing a pointer to a structure

[Ron Michael Khu <ronkhu@ntsp.nec.co.jp>]

Err.. at least two individuals have already tried to explain it you...

for test two, maybe there's somesort of a glib technicality that made u 
get away
with writing outside out of the limits u have alloted for ur datastruct...

but it doesnt mean if u're getting no errors when using even values for 
MAXNUM(or factors of 4 for that matter),
that there's nothing wrong with ur loop...(and there is... almost 
everyone in this list will point it out to you..)

I may not know how u got away with it by using even values for maxnum,
but almost everbody knows that an array created with N elements/slots in 
C,C++ or in java
could only be safely accessed/manipulated via the indices 0...N-1 
(unless if u're an expert in memory manipulation)




p.boehm@d-trust.net wrote:

>sorry, but it isn't a problem of loop. check this while running the prog...
>
>test one:
>
>     #define MAXNUM 7
>     compile it and run ...
>     you'll see while freeing ptr->next[0] an -EFAULT occours.
>
>test two:
>
>     #define MAXMUM 8
>     compile it and run ...
>     you'll see freeing ptr->next[0] works fine.
>
>my question: why it is so.
>
>thanks
>pb
>
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