On 28 Jan 2009, at 2:24 am, Jeremy Pereira wrote:

Yes. That is correct, but since buffer is already a pointer to the first byte of the array and then you are taking a reference to it, key will end up containing the address of the buffer. You really need:

uint key = *(uint*)buffer;



That's incorrect. Or rather, in this case it doesn't make any difference, but the use of '&' is more general as it works whether buffer is an array or not.

When you declare:

uint8 buffer[8];

You've reserved 8 bytes on the stack. Whether you use 'buffer' or '&buffer' you obtain the same address, as C treats array variables as pointers. But:

uint8 buffer;

You get very different results from 'buffer' and '&buffer' so in the interests of defensive programming, using '&' is allowing your code to tolerate a change to the buffer declaration without breaking. Because of the additional cast *(int*) such a change would go unnoticed by the compiler but probably have a very bad outcome at runtime. It's a good habit IMO to always take the address in these cases to make it clear in your code what your intentions were when you wrote it.

--Graham


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