From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Michael Kerrisk (man-pages)" Subject: Re: clock(3) man page: precision vs accuracy Date: Sat, 13 Sep 2014 19:33:19 -0700 Message-ID: <5414FE6F.2030603@gmail.com> References: <20140912120804.GE4404@xvii.vinc17.org> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20140912120804.GE4404-Ljv1qFl2dU+MDATNRQa/ww@public.gmane.org> Sender: linux-man-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Vincent Lefevre Cc: mtk.manpages-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org, linux-man-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: linux-man@vger.kernel.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/ -- To unsubscribe from this list: send the line "unsubscribe linux-man" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html