[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: ✘ gpxlogger
From: |
Gary E. Miller |
Subject: |
Re: ✘ gpxlogger |
Date: |
Sat, 14 Aug 2021 16:03:10 -0700 |
Yo Fred!
On Sat, 14 Aug 2021 15:49:14 -0700 (PDT)
Fred Wright <fw@fwright.net> wrote:
> On Thu, 12 Aug 2021, Gary E. Miller wrote:
>
> > Another fix to gpxlogger. I hope the last. Please test.
> >
> > The problem was the lack of a timeout when reading gpsd from DBus.
>
> I just pushed a fix for platforms lacking clock_gettime(). Aside
> from the needed include, the current fallback only implements
> CLOCK_REALTIME, which is the only type that's been used so far, and
> it's generally fine for timeouts. For really accurate intervals, one
> should use CLOCK_MONOTONIC_RAW, not CLOCK_MONOTONIC, since the latter
> only omits the step adjustments, and still includes the same
> intentional rate errors for slewing as CLOCK_REALTIME, typically on
> the order of 500ppm. CLOCK_MONOTONIC is pretty much never what you
> really want.
Thanks!
I just notice the CLOCK_MONOTONIC is not good for timeouts. From the
man page:
"This clock does not count time that the system is suspended."
> With the timeout it indeed now only hangs for five seconds instead of
> forever waiting for dbus, though ^C still has no effect as expected.
I'm not sure what you expected? ^C now working for me, but maybe we
have different tests?
> In the process, I did some testing with and without dbus running, and
> found that gpxlogger is never able to find the local gpsd without
> dbus, even in the perfectly normal case where gpsd is running with a
> receiver providing fixes.
By default, gpslogger only tries DBus. To use TCP, you have to start
with:
gpxlogger localhost
or specify the export method:
gpxlogger -e shm
gpxlogger -e sockets
Fallback was never part of the gps_mainloop() code.
> Meanwhile, cgps has no trouble. I suspect
> that the dbus failure is failing to fall back to the non-dbus method
> of connecting.
I make no assumptions. No other gpsd client has ever used gps_mainloop()
and that function is way more complicated than I expected.
> > No other client uses gps_mainloop() so many bugs in there...
>
> Indeed. It still nees to interact better with signals.
What exactly is failing for you?
RGDS
GARY
---------------------------------------------------------------------------
Gary E. Miller Rellim 109 NW Wilmington Ave., Suite E, Bend, OR 97703
gem@rellim.com Tel:+1 541 382 8588
Veritas liberabit vos. -- Quid est veritas?
"If you can't measure it, you can't improve it." - Lord Kelvin
pgpEoFNMXqNFK.pgp
Description: OpenPGP digital signature
- ✘3.23~rc1 -- gpxlogger, Gary E. Miller, 2021/08/02
- Re: ✘3.23~rc1 -- gpxlogger, Fred Wright, 2021/08/02
- Re: ✘3.23~rc1 -- gpxlogger, Gary E. Miller, 2021/08/03
- Re: ✘3.23~rc1 -- gpxlogger, Fred Wright, 2021/08/03
- Re: ✘3.23~rc1 -- gpxlogger, Gary E. Miller, 2021/08/03
- Re: ✘3.23~rc1 -- gpxlogger, Gary E. Miller, 2021/08/04
- Re: ✘3.23~rc1 -- gpxlogger, Fred Wright, 2021/08/06
- ✘ gpxlogger, Gary E. Miller, 2021/08/12
- Re: ✘ gpxlogger, Fred Wright, 2021/08/14
- Re: ✘ gpxlogger,
Gary E. Miller <=
- Re: ✘ gpxlogger, Fred Wright, 2021/08/14
- Re: ✘ gpxlogger, Gary E. Miller, 2021/08/14