Re: Add pselect, ppoll system calls.

[David Woodhouse <dwmw2@infradead.org>]

On Mon, 2005-06-13 at 09:10 -0700, Ulrich Drepper wrote:
> poll()'s timeout value is measrued in milliseconds.  Using a 32bit
> value, as implied by using 'int' for the type, limits the mximum
> timeout to be 2^31-1 milliseconds, which means about 24 days.

Ah, OK. I thought you were talking about the timespec in pselect(),
because that's what you quoted. 

Yes, we should make the time for ppoll() a 64-bit value, so you can
request a time period longer than 24 days. Shall we also switch to
microseconds?

>   Believe it or not, people are complaining about this.  Changing the
> timeout to a 64bit millisecond timeout would lift the limitation from
> the API's  POV.  I don't know what limitations exist in the kernel
> itself.

Indeed. The ABI will be set in stone, but we have some leeway to fix the
implementation details of the kernel's limitations -- such as the fact
that on a 32-bit box with HZ == 1000, any requested timeout above
MAX_LONG milliseconds (24 days) will actually end up being infinite.

-- 
dwmw2

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