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    <pre><code>#include &lt;stdlib.h&gt; // did you included this? void* MYmemmove (void* destination, const void* source, size_t num) { char *Source = source, *Destination = destination; char *Middle = malloc( sizeof(char) * num ); // midbuf for (int i = 0; i &lt; num ; i++) { Middle[i] = Destination[i]; // Copy source to midbuf } for (int i = 0; i &lt; num ; i++) { Destination[i] = Middle[i]; // Copy midbuf to destination } free(Middle); // free memory allocated previously with malloc return destination; } </code></pre> <p>Acces violation could occur because you didn't included libraries needed for malloc (standard c doesn't throw errors in your face if you forgot a function definition). You don't need to mark pointers as NULL since there's no garbage collection in C (pointers are just that - pointers. Addresses to a point in memory, not memory themselves).</p> <p>think about pointers like</p> <p>addres of pointer 0x1243 0x4221 Destination -> {some kind of data}</p> <p>Destination = 0x1243 *Destination = whatever value is currently at addres 0x4221</p> <p>You can't also index void pointers. You must first cast them to some type, so the compiler knows how much offset they need.</p> <p>Destination[x] = *(Destination+x)</p> <p>a char is 1 byte, so char pointer will really get moved by x bytes, but an int is 4 bytes, and an int pointer will get moved by 4*x bytes. Don't worry too much if it sounds technical, it'll be important when you'll get to something really low level ;)</p>
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    1. POHeap corruption from memory allocation using malloc: why did it happen?
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    1. CO-1 `memmove` works even when the two arrays overlap; this implementation will create nonsense in that case.
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      1. USPete Becker
    2. CO@PeteBecker indeed! http://en.wikipedia.org/wiki/Aliasing_%28computing%29
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      1. USAlexander Kondratskiy
    3. CO@Pete fixed that
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Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

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