Re: open SHM data only after cgps start

[Hans Kurscheidt]

Hi,

mails are crossing!

Last question, I don't know what you mean with systemD (UMB) (UMCest) etc.

RGDS

hk


Am 05.02.2021 um 19:51 schrieb Gary E. Miller:
> Yo Hans!
>
> On Fri, 5 Feb 2021 18:52:19 +0100
> Hans Kurscheidt <lve0200@gmail.com> wrote:
>
> > I am now more than ever convinced that there's an issue in gpsd!
> I think Fred has the answer, he knows much more about systemd(umb) tha I do.
>
> > 1): fresh & clean boot; sudo lsof | grep /dev/ttyACM0 (my device
> > (ublox 6 via USB)) => nothing open.
> Not so fast.  As Fred said, systemd does not start gpsd until the
> first network client connection.  SHM connections are ignored by
> systemd(ubmer).
>
> You can verity this way:
>
> netstat -apn | fgrep :2947
>
>
> > 2) starting my app; sudo lsof | grep /dev/ttyACM0 (my device (ublox
> > 6)) => nothing open
> Ditto above.
>   
> > starting cgps in parallel; sudo lsof | grep /dev/ttyACM0
> > gpsd        700           nobody    9u      CHR      166,0 0t0
> > 14619 /dev/ttyACM0
> >
> > my app starts to receive data as well, like cgps.
> Ditto above.  Fred explained this.
>
> > after a while, my app does not receive anymore data (most likely when
> > buffer has become empty); sudo lsof | grep /dev/ttyACM0 (my device
> > (ublox 6)) => nothing open.
> No.  Systemd(umbest) say no network connections and killed gpsd.
>
> RGDS
> GARY
> ---------------------------------------------------------------------------
> Gary E. Miller Rellim 109 NW Wilmington Ave., Suite E, Bend, OR 97703
>         gem@rellim.com  Tel:+1 541 382 8588
>
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