struct timex and Linux adjtimex()

[Poul-Henning Kamp]

--------
Konstantin Belousov writes:
> On Thu, Dec 03, 2020 at 10:17:51AM +0000, Poul-Henning Kamp wrote:
> > --------
> > Konstantin Belousov writes:
> > 
> > > 1. Implement new syscall, which would take extended struct timex.
> > >    ntp_adjtimex() perhaps should be kept for backward compatibility.
> > >    [It does not matter where struct timeval is placed in the updated
> > >    struct timex, see below].
> > 
> > That would break all ports with timekeeping software.
> Why ?

Last I looked they all had "#ifdef FreeBSD use ntp_adjtim()", so if
you rename it to ntp_adjtimex() you break them.

I see no problem having a #define to alias timex() to ntp_adjtime(),
but I doubt it would make life easier for anybody.  (I think we used
to have that and it got GC'ed.)

*If* we want to do this, the right way is to extend struct timex and
let ntpadjtime(2) handle the new modes.

-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
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FreeBSD committer       | BSD since 4.3-tahoe    
Never attribute to malice what can adequately be explained by incompetence.