<sys/queue.h> bikeshed proposal

[Poul-Henning Kamp]

In message <20070315134300.GE28354 at comp.chem.msu.su>, Yar Tikhiy writes:

>Yeah, <sys/queue.h> can present a challenge in understanding an
>implementation of basic data structures and related algos. :-)
>You thought that tqe_prev points to the whole entry structure when
>making the patch, didn't you?

Nah, I was just generally sleepy I think.

>Personally, I cannot explain to myself why in the double-linked
>structs the prev member points to the next member in the previous
>list element and not to the previous list element itself.  Could
>anybody with CS education explain merits of the current approach?

It allows us to isolate casts to those few backwards functions,
all the forwards functions are type correct.

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