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Subject: Re: Unchecked flags in statx(2) [Should be fixed before 4.11-final?]
To: Andreas Dilger <adilger@dilger.ca>
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From: "Michael Kerrisk (man-pages)" <mtk.manpages@gmail.com>
Message-ID: <6b5580c6-e163-0404-17e4-6c1c3777bc76@gmail.com>
Date: Fri, 21 Apr 2017 21:19:31 +0200
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Hello Andreas,

On 04/21/2017 08:16 PM, Andreas Dilger wrote:
> On Apr 21, 2017, at 7:13 AM, Michael Kerrisk (man-pages) <mtk.manpages@gmail.com> wrote:
>>
>> On 04/21/2017 03:01 PM, David Howells wrote:
>>> Michael Kerrisk (man-pages) <mtk.manpages@gmail.com> wrote:
>>
>>> (3) There's no problem with asking for extra bits, even if the running
>>>     kerneldoes not support them, because the kernel tells you in its
>>>     response what fields it actually gave you.
>>
>> It's this piece that I overlooked. Makes sense, of course.
>> Sorry for the noise!
> 
> I agree with David that we don't want to return an error if the application
> asks for more bits than the kernel supports, otherwise the interface would
> be useless.

Yes, it's clear to me now.

> Maybe this implies that this needs to be explained more clearly in the
> statx man page?

Precisely; my thought also.

Cheers,

Michael 


-- 
Michael Kerrisk
Linux man-pages maintainer; http://www.kernel.org/doc/man-pages/
Linux/UNIX System Programming Training: http://man7.org/training/