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    <p>One quick hint about pointers: if you are casting it, you are probably doing something wrong.</p> <p>As for your question. I am not sure what <code>item</code> is in your problem. In your first part you've already discovered how to acces a member in your array. You could simply use it:</p> <pre><code>void *get_item(Thing *c, int index) { return *(c-&gt;array + index); // or return c-&gt;array[index]; } </code></pre> <p>If you need the address of the pointer at index:</p> <pre><code>void **get_item_cell(Thing *c, int index) { return c-&gt;array + index; // or return &amp;c-&gt;array[index]; } </code></pre> <p>In the second part, you don't dereference the pointer (for + option), or take the address of array result, since it automatically dereferences it.</p> <hr> <p>EDIT: I think I now know what you want. You have a function similar to my second one above, but it is:</p> <pre><code>void *get_item_cell(Thing *c, int index) { return (void *)(c-&gt;array + index); } </code></pre> <p>You want to dereference the value returned from this function, and access the object. In that case, you can only use Option 4 safely. Since you don't have the index, you cannot move to any other cell (you don't know if you are at the end of the array, or at the beginning - so no additions or subtractions). You can only fix the mistake of the above function: cast to <code>void **</code>, and then dereference it: <code>*(void **)item</code>. This will give you a <code>void *</code>. If you want to access the object pointed from this cell, you need to cast that to the correct type as well: <code>some_object_ptr *obj = *(void**)item</code>.</p>
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    1. POhow to use void ** pointer correctly?
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    1. COoh, so returning part is in different function that it does not know the index and void * item points to the array of cell
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    2. COOnly my understanding of what you want to do. If you have the address of the pointee (an object in the array), and want to return to either the index or the cell of the array, you'll have to loop through each cell, check if the pointee is the same object as the one you want, then return the relevant information when it is. If this is what you want, I can add that to my answer.
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