Re: Memory Leak Explanation

From: marbac (marbac_at_chello.at)
Date: 05/06/04 

Date: Thu, 06 May 2004 09:31:30 GMT

Hi,

> prtr1 = (char *) malloc (512);
> prtr2 = (char *) malloc (512);
First you allocate 512 bytes for ptr1 on the heap
After this you allocate !another! 512 bytes for ptr2 on the heap.

> prtr2 = ptr1;

An then follows the mistake ... you move away ptr2 from the 512 bytes
allocated for ptr2. There is no other pointer pointing to this
"ptr2-512bytes". You are not able to delete (free) this 512 bytes from
now on (memory leak).

> free(prt1);

Here you delete (free) the 512 bytes of ptr1 and ptr2.

> free(ptr2);

You deleted (free) the 512 bytes of ptr2 yet because you deleted the 512
bytes
of ptr1 -> runtime error

But i also have a question.
If i allocate an array, i have to delete it with delete [] instead of
delete.
Is this not necessary with free?

regards marbac

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