>
> On Tue, 17 Aug 1999, David Weinehall wrote:
>
> > On Mon, 16 Aug 1999, Linus Torvalds wrote:
> >
> > >
> > >
> > > On Mon, 16 Aug 1999, Gerard Roudier wrote:
> > > >
> > > > Why is jiffies type still 'unsigned long', given that all calculations
> > > > that try to be not too wrong with wrap-around just cast timer values to
> > > > signed long?
> > >
> > > Why not?
> > >
> > > You shouldn't really do compares on it anyway, so the type doesn't matter.
> > > And to me, "unsigned" makes much more sense for time as it is implemented
> > > in the kernel - it never goes negative, but it can wrap. That's basically
> > > what "unsigned" means.
> > >
> > > Also the C standard actually guarantees nice wrapping behaviour for
> > > unsigned, something it doesn't guarantee for signed values. So as long as
> > > you're working with wrapping values, you should always use unsigned. We
> > > then at the last possible moment know that we're playing with a two's
> > > complement machine, and that's where we do the signed cast to test the
> > > high bit to make it easy on the compiler, but you could conceptually think
> > > of it as a test for the high bit (which is portable C) rather than as a
> > > test for the sign (which is _not_ portable C, but nobody cares because
> > > nobody sane does anything but two's complement).
> > >
> > > So I really don't see the point of trying to change the type to anything
> > > else or trying to hide it with some random new typedef that doesn't buy
> > > you anything in real life. Don't abstract things away unless you get some
> > > real _advantage_ from the abstraction, and I don't see the advantage.
> > >
> > > Linus
> >
> > >From just a quick scan (grep + ocular-investigation), there seem to be at
> > least a few places left in the kernel where jiffies are treated as int,
> > not unsigned long. Are those left on purpose, or should I fix 'em up?!
>
> Do you mean that you inspected the whole 2419 lines of code that refers to
> jiffies and investigated the corresponding source files ? ;-)
> I would be impressed if I really beleived so. :)
Look, I'm still using the MCA-bus, but I'm not ALL stupid... :^) Of course
I didn't examine all the code. Why? Because I didn't know whether mr
master-penguin wanted it to be that way or not.
> All this mess-up for, in fact, a simple problem. But as we know, dealing
> with date and time hasn't been a great success in I.T. The Y2K problem
> will be our punishment.
Yup.
[snip]
/David
_ _
// David Weinehall <tao@acc.umu.se> /> Northern lights wander \\
// Project MCA Linux hacker // Dance across the winter sky //
\> http://www.acc.umu.se/~tao/ </ Full colour fire </
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