Re: A pettiness question.

[Bill Davidsen]

liyu wrote:
> Hi, All.
>      I found there are use double operator ! continuously sometimes in 
> kernel.
> e.g:
>
>    static inline int is_page_cache_freeable(struct page *page)
>    {
>        return page_count(page) - !!PagePrivate(page) == 2;
>    }
>
>    Who would like tell me why write like above?
>    
!!(N) is easier to write than ((N) ? 1 : 0)
--
   -bill davidsen (davidsen@xxxxxxx)
"The secret to procrastination is to put things off until the
 last possible moment - but no longer"  -me

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