>From: beaucham@phy.ulaval.ca (Dominique Beauchamp)
>
>private:
> PIXEL *array;
> INT size;
>
>And the constructor allows an arraw of 1 pixel as the default size:
>
>IMAGE::IMAGE()
>{
> size=1;
> array=new PIXEL[size];
> assert...
>}
>
>Then the destructor destroy it like this:
>
>IMAGE::~IMAGE()
>{
> delete [] array; // yes I'm using 3.0...
>}
>
>Here, an acces violation occures (SYS3175 on OS/2)

 There is nothing wrong with your code, at least that
you have shown. Its is probable that the code you have
not shown -- because you didnt write it -- is the error.

 This error is very common, and is almost always due
to not defining an copy constructor and assignment operator.

 If you dont define:

 struct IMAGE { ....
  IMAGE(IMAGE const& x) { .. } // copy constructor


the compiler generates it by copying each element. It copies
the image POINTER. SO:

 IMAGE x; // an image
 IMAGE y = x; // copy it
 ..
 // y gets destroyed, your destructor deletes the POINTER
 // x gets destroyed, your destructor deletes the POINTER
 // .. AGAIN!!

You need:

 IMAGE(IMAGE const& x) { .. size=x.size;
  array = new PIXEL[size];
  memcpy(array, x.array, size); // copy the array
 };

or something similar. You have to do this for assignment too.

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