From: "Michael Kerrisk (man-pages)" <mtk.manpages-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
To: Vincent Lefevre <vincent-buymaDBGzMOsTnJN9+BGXg@public.gmane.org>
Cc: mtk.manpages-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org,
linux-man-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
Subject: Re: clock(3) man page: precision vs accuracy
Date: Sat, 13 Sep 2014 19:33:19 -0700 [thread overview]
Message-ID: <5414FE6F.2030603@gmail.com> (raw)
In-Reply-To: <20140912120804.GE4404-Ljv1qFl2dU+MDATNRQa/ww@public.gmane.org>
On 09/12/2014 05:08 AM, Vincent Lefevre wrote:
> http://man7.org/linux/man-pages/man3/clock.3.html contains:
>
> In glibc 2.17 and earlier, clock() was implemented on top of
> times(2). For improved precision, since glibc 2.18, it is
> ^^^^^^^^^^^^^^^^^^
> implemented on top of clock_gettime(2) (using the
> CLOCK_PROCESS_CPUTIME_ID clock).
>
> This looks strange. The user doesn't seek improved precision, but
> improved accuracy: if one gets more digits but the value itself is
> less accurate (i.e. the error against the ideal value is larger),
> this is bad. Perhaps changing "precision" to "accuracy" would be
> correct (I assume that the real goal of the change was not just
> improved precision, but more importantly the resulting improved
> accuracy). I've reported a bug about the glibc documentation:
>
> https://sourceware.org/bugzilla/show_bug.cgi?id=17383
It looks to me like your supposition is correct, Vincent.
I have changed "precision" to "accuracy".
Cheers,
Michael
--
Michael Kerrisk
Linux man-pages maintainer; http://www.kernel.org/doc/man-pages/
Linux/UNIX System Programming Training: http://man7.org/training/
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prev parent reply other threads:[~2014-09-14 2:33 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-09-12 12:08 clock(3) man page: precision vs accuracy Vincent Lefevre
[not found] ` <20140912120804.GE4404-Ljv1qFl2dU+MDATNRQa/ww@public.gmane.org>
2014-09-14 2:33 ` Michael Kerrisk (man-pages) [this message]
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