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SubjectRe: bugreport: poll() timeout always takes 10ms too long
Tachino Nobuhiro wrote:

>
> Hello,
>
> At Fri, 22 Jun 2001 11:52:12 +1000,
> raf@raf.org wrote:
> >
> > [1.] One line summary of the problem:
> >
> > poll() timeout always takes 10ms too long
> >
> > [2.] Full description of the problem/report:
> >
> > Select() timeouts work fine. A timeout between 10n-9 and 10n ms times
> > out after 10n ms on average. Poll() timeouts between 10n-9 and 10n ms,
> > on the other hand, time out after 10(n+1) ms on average. It's always a
> > jiffy too long. This means it's impossible to set a 10ms timeout using
> > poll() even though it's possible using select(). The programs and their
> > output below [6] demonstrate this. The same behavious occurs with
> > linux-2.2 and linux-2.4.
>
>
> I think this is correct behavior. The Single UNIX Specification
> describes about the timeout parameter of poll() as follows,
>
> If none of the defined events have occurred on any selected
> file descriptor, poll() waits at least timeout milliseconds
> for an event to occur on any of the selected file descriptors.
>
> On the other hand, select(),
>
> If the specified condition is false for all of the specified
> file descriptors, select() blocks, up to the specified timeout
> interval, until the specified condition is true for at least
> one of the specified file descriptors.

ok, it's a correct behaviour.
but having both poll and select
timeout at the time specified
would also be correct behaviour.
better than that, it would be
expected behaviour.

raf

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