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Date:	Sun, 13 Jan 2013 20:52:30 -0800
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Subject:	Re: Using the free(*ptr) routine and getting an exception, "Exception: STATUS_ACCESS_VIOLATION"
From:	Dan Kegel <dank AT kegel DOT com>
To:	cygwin AT cygwin DOT com
Cc:	yzfury AT gmail DOT com
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On Sun, Jan 13, 2013 at 7:55 PM, YZFury <yzfury AT gmail DOT com> wrote:
> int *ptr = malloc(sizeof(*ptr));
>         int x = 87;
>         ptr = &x;
>         printf("%d", *ptr);
>         free(ptr);//it goes wrong here

As you probably know, you can't call free() on a pointer
that didn't come from malloc().  ptr's first value came from malloc,
but you overwrote that with
   ptr = &x;
Perhaps you meant
   *ptr = x;
So you're a level of indirection off.
- Dan

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