Re: Bit ****fting

David Shen wrote:
> Brig White wrote:
>> { Multi-posted article. -mod }
>>
>> Why is it than when I bit ****ft to the right with a signed integer 
>> type, all
>> the higher order bits above the move are set but when I ****ft with an
>> unsigned type, they are cleared?
>>
>>
>>
> 
> This is so called Arithmetic Bitwise operation. I you want the zero to
> be fill in when you do right bit ****ft, you need a Logical Bitwise
> operation.
> 
> Please refer to http://en.wikipedia.org/wiki/Bitwise_operation



Keep in mind that in ANSI C at least (not sure if C++ is different),
right ****ft of signed ints is undefined (or implementation defined?).
Most modern system probably do  sign extension (arithmetic ****ft), but
it's not guaranteed by the spec.

If you want logical ****ft you could probably cast to unsigned int and
then ****ft.

-- Bill

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