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From: Giorgos Keramidas <keramida@ceid.upatras.gr>
To: unga888@yahoo.com
References: <55974.31287.qm@web57001.mail.re3.yahoo.com>
Date: Sun, 21 Sep 2008 01:15:36 +0300
In-Reply-To: <55974.31287.qm@web57001.mail.re3.yahoo.com> (Unga's message of
	"Sat, 20 Sep 2008 07:04:03 -0700 (PDT)")
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Cc: freebsd-questions@freebsd.org, Nash Nipples <trashy_bumper@yahoo.com>
Subject: Re: Segmentation fault when free [SOLVED]
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On Sat, 20 Sep 2008 07:04:03 -0700 (PDT), Unga <unga888@yahoo.com> wrote:
>On Sat, 9/20/08, Giorgos Keramidas <keramida@ceid.upatras.gr> wrote:
>>> : free(0xbfbfc9c9)
>>>
>>> 1. This clearly shows my program is trying to free a memory that
>>> has not been allocated. How it could have happened?
>>
>> Aha.  This looks remarkably like an address in the runtime stack.  It
>> usually happens when you have a function that returns the address of
>> a 'local' variable, instead of a newly allocated heap area, i.e.:
>>
>>     char *
>>     function(void)
>>     {
>>         char buffer[100];
>>
>>         return buf;
>>     }
>
> This was indeed the case, worst yet, I was trying to free a part of
> the buffer (as per your example above) by mistake which was not
> allocated by malloc.
>
> Thank you all who helped me.

Great!  You are welcome, of course :)