>  JV> I don't think you described a circular buffer..  
>  JV> Whadya mean: 'buffer is empty' head=tail ?  
>  JV> That's a stacked buffer. 
> 
> Ummm.. a stack _is_ a LIFO buffer.. you read from and write to the stack
> using the "head" pointer. If you re-read, I said "write at the tail, read
> from the head", and that is a FIFO buffer, a queue.
LIFO,FIFO... the thing is in a circle. What if I'm reading at the middle
of it and a byte comes in?  Always drop it on the oldest byte, reading
has nothing to do with that. You're going to need some more pointers. 
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