Re: GPSD Service: open SHM data only after cgps start

[Gary E. Miller]

Yo Hans!

On Thu, 4 Feb 2021 22:18:44 +0100
Hans Kurscheidt <lve0200@gmail.com> wrote:

> Well I hope this goes in the previous thread, because I can't see a
> possibilityRe: GPSD Service: open SHM data only after cgps start to
> "answer" other than ending up sending private mails...

The traffic here is light enough that we can figure out threads.

> Sorry, I'm stuck w/ 3.16 for this distro using apt etc.. I tried to
> change it to 3.22 from a Debian gpsd.deb package, but I ended up
> in a maze of dependencies and finally I bricked the whole system!

All you really need is gcc or llvm for basic functionality.  The
exact steps for Debian are here:

https://gpsd.io/installation.html#_other_debian_derivatives_including_stock

If that fails, please file a bug report as detailed here:

https://gpsd.io/SUPPORT.html#_issue_tracker


> I'm gonna guess you forgot to  set the "-n" flag to gpsd.
> 
> 
> I am not a gpsd expert, but isn't the -n flag for the gpsd console
> start??!!

Nope.  All gpsd command line flags work the same regardless of how gpsd
is started.

The -n option is documented here:

https://gpsd.io/gpsd.html#_options

But your 5 year old version will be different, so use your obsolete
man apge.

Without the -n, client startup can be very slow.

> I want to connect from my application to the GPSD SHM, using "open"
> w/ GPSD_SHARED_MEMORY w/out having to start something at console
> level.

Of course.

> I the best of all possible worlds, gpsd and my app start at
> boot as a service.

Of course.  But getting sysmtemd(ubmer) to do that is non-obvious.
I can't help you with sysmted(umbest), maybe someone else can.

My guess is your systemd(ingleberry) config is not starting gpsd until
it gets a client connection.  Blame systemd(reck), not gpsd.

Did you read the section on troubleshooting gpsd?

https://gpsd.io/troubleshooting.html#systemdtroubleshooting

> BTW, I introduced the dependency from gpsd and dbus in my app Unit
> systemd file.

Unrelated to your issues.

> still clueless

And you did not answer my questions:

> > I do not recommend running gpsd under systemd(umb).  To debug it
> > we need to see the contents of your gpsd.service file and thse two
> > files:
> >
> >      /etc/default/gpsd
> >      /etc/sysconfig/gpsd

You asked for help.  You help us help you by answering our questions.

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

pgpurIFhtYEat.pgp
Description: OpenPGP digital signature