Hello Laurent, Thanks for working on this. I have one question; see below. On 11/29/2014 12:02 AM, Laurent Georget wrote: > Le 28/11/2014 22:00, Richard Cochran a écrit : >> On Fri, Nov 28, 2014 at 02:40:44PM +0100, Laurent Georget wrote: >>> @@ -101,7 +99,19 @@ combination of zero or more of the following bits: >>> Ordinary users are restricted to a zero value for >>> .IR modes . >>> Only the superuser may set any parameters. >>> +.PP >>> +Support for TAI (Atomic International Time, for a complete explanation >>> about >>> +what it is and what is the difference between TAI and UTC, see >>> +.UR http://www.bipm.org/en/bipm/tai/tai.html >>> +.I BIPM >>> +.UE ) >>> +has been added in version 2.6.29. For any clock, the TAI offset may >> >> Not for "any clock", just for CLOCK_REALTIME. > > Considering that this is the only one representing the "human" time and > supporting an adjtime action, indeed, it's not relevant for anything > else than the realtime clock. > >> >>> +be calculated by adding a value to the UTC offset which is updated when a >>> +leap second is added or deleted. >>> .br >>> +All the offsets in the timex structure are expressed between the value >>> of the >>> +clock and the corresponding value (e.g. TAI offset is the difference >>> between >>> +the clock and the TAI, not between TAI and another value such as UTC). >> >> The TAI offset is just (TAI - UTC). That's all. >> > > Yes, my mistake, I misunderstood the part about timekeeping > (__timekeeping_set_tai_offset() in kernel/time/timekeeping.c, line 815) > which does store the offset in several formats (monotonic -> TAI and UTC > -> TAI). But this is not directly related to the timex value. Aniway > this is not very relevant in the man page. > > Thank you for your comments. Below is a new version of the patch. Less > unrelevant chit-chat, more useful information (hopefully). > > > diff --git a/man2/adjtimex.2 b/man2/adjtimex.2 > index 20a2f0b..871e607 100644 > --- a/man2/adjtimex.2 > +++ b/man2/adjtimex.2 > @@ -26,9 +26,6 @@ > .\" Modified 2004-05-27 by Michael Kerrisk <mtk.manpages@xxxxxxxxx> > .\" Modified 2014-11-28 by Laurent Georget <laurent.georget@xxxxxxxxxx> > .\" > -.\" FIXME Document ADJ_TAI (added in Linux 2.6.26) > -.\" commit 153b5d054ac2d98ea0d86504884326b6777f683d > -.\" > .\" FIXME Document ADJ_MICRO and ADJ_NANO (added in Linux 2.6.26) > .\" commit eea83d896e318bda54be2d2770d2c5d6668d11db > .\" Author: Roman Zippel <zippel@xxxxxxxxxxxxxx> > @@ -74,6 +71,17 @@ struct timex { > (read-only) */ > struct timeval time; /* current time (read-only) */ > long tick; /* usecs between clock ticks */ What is the following piece about? Did you mean to include it in this patch? > + > + long ppsfreq; /* pps frequency (scaled ppm) (read-only) */ > + long jitter; /* pps jitter (usec) (read-only) */ > + int shift; /* interval duration (sec) (read-only) */ > + long stabil; /* pps stability (scaled ppm) (read-only) */ > + long jitcnt; /* jitter limit exceeded (read-only) */ > + long calcnt; /* calibration intervals (read-only) */ > + long errcnt; /* calibration errors (read-only) */ > + long stbcnt; /* stability limit exceeded (read-only) */ > + > + int tai; /* TAI offset (s) (read-only) */ > }; Thanks, 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@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
