Re: [PATCH 2/2 v3] adjtimex.2: add explanation on ADJ_TAI mode

["Michael Kerrisk (man-pages)" <mtk.manpages@gmail.com>]

Hello Laurent,

On 11/30/2014 11:14 AM, Laurent Georget wrote:
> This patch includes the adjtimex mode ADJ_TAI, intended to update the
> TAI offset. 

Thanks. Applied, with a few rewordings (which you can find in Git).
One point/question below.

> There are other FIXMEs in the man page and it's a bit
> outdated. I'll be on it once those first patches are accepted (to be
> sure to do the right thing).

I would be happy to get more such patches.

> diff --git a/man2/adjtimex.2 b/man2/adjtimex.2
> index 0b919c5..396b8cc 100644
> --- a/man2/adjtimex.2
> +++ b/man2/adjtimex.2
> @@ -24,9 +24,7 @@
>  .\" Modified 1997-01-31 by Eric S. Raymond <esr@thyrsus.com>
>  .\" Modified 1997-07-30 by Paul Slootman <paul@wurtel.demon.nl>
>  .\" Modified 2004-05-27 by Michael Kerrisk <mtk.manpages@gmail.com>
> -.\"
> -.\" FIXME Document ADJ_TAI (added in Linux 2.6.26)
> -.\"		commit 153b5d054ac2d98ea0d86504884326b6777f683d
> +.\" Modified 2014-11-30 by Laurent Georget <laurent.georget@supelec.fr>
>  .\"
>  .\" FIXME Document ADJ_MICRO and ADJ_NANO (added in Linux 2.6.26)
>  .\"		commit eea83d896e318bda54be2d2770d2c5d6668d11db
> @@ -101,6 +99,7 @@ combination of zero or more of the following bits:
>  #define ADJ_ESTERROR          0x0008 /* estimated time error */
>  #define ADJ_STATUS            0x0010 /* clock status */
>  #define ADJ_TIMECONST         0x0020 /* pll time constant */
> +#define ADJ_TAI               0x0080 /* TAI offset */
>  #define ADJ_TICK              0x4000 /* tick value */
>  #define ADJ_OFFSET_SINGLESHOT 0x8001 /* old-fashioned adjtime() */
>  .fi
> @@ -110,6 +109,24 @@ Ordinary users are restricted to a zero value for
>  .IR modes .
>  Only the superuser may set any parameters.
>  .br
> +In the case of
> +.BR ADJ_TAI ,
> +as
> +.I buf->tai
> +is read-only, the new value is passed through
> +.IR buf->constant ,
> +therefore
> +.B ADJ_TIMECONST
> +and
> +.B ADJ_TAI
> +should probably not be used at the same time.

"should probably not" seems a little weak to me. Surely it is rather the
case that they *must not* be used at the same time. I changed it to "must not".

Thanks,

Michael


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