Re: [gpsd-users] strange - currently only few satellites

[hans mayer]

Dear David,

This is actually a nice idea to feed MRTG with satellites numbers.
MRTG is running all 5 minutes typically. So it would be nice to have
an average number of satellites of the last 5 minutes instead of
just the value when MRTG is executed.

I setup several MRTG's in the past but always reading the values
with SNMP. No idea how to read data in a different way.

This simple script below would just print out the number of
available satellites at moment when it's started.


gpspipe -r | egrep --line-buffered  'GPGSA' | head -1 | gawk  '-F,' '
{
 CNT=0 ;
 if ( $1 ~  /GPGSA/ ) {
   for (i = 1; i <= NF; i++) {
     if ( $i != "" ) {
       CNT++ ;
     } ;
   } ;
   print ( CNT - 6 ) ;
 } ;
}'



Kind regards
Hans

--



Am 09.04.2016 09:58, schrieb David J Taylor:
> Dear David,
>
> you can download the source from github:
> https://github.com/hans-mayer/sat_usage
> if there are any questions tell me.
>
> // hans
> ==================================
>
> Hans,
>
> Many thanks for that that, most helpful!  What I actually need is a
> script (or whatever) which returns the number of satellites being used
> by gpsd for a fix and I'll use this as input to MRTG (likely via the
> SNMP pass mechanism).  Although I am completely unfamiliar with Linux
> shell commands, I've been able to simplify your script down to:
>
> ________________________________________
> gpspipe -r | egrep --line-buffered  'GPGSA' | stdbuf -o0 gawk  '-F,' '
> {
>   CNT=0 ;
>   if ( $1 ~  /GPGSA/ ) {
>     for (i = 1; i <= NF; i++) {
>       if ( $i != "" ) {
>         # print ( $i ) ;
>         CNT++ ;
>       } ;
>     } ;
>     print ( CNT ) ;
>   } ;
> }'
> ________________________________________
>
> which is near to what I need, with two exceptions:
>
> 1 - The script runs continuously.  What I need is just to get the
> current number of satellites and exit.  Run once, not every second.
> Something like a "break" after printing the count.  My Linux knowledge
> isn't up to knowing how to do this!
>
> 2 - What I would like is also the number of satellites gpsd is actually
> using for a fix.  Comparing the script result with "cgps -s" for
> example, the value returned by the script is the total number of
> satellites in the right-hand cgps column, whereas I would also like the
> number of satellites with "Y" against them - satellites being used.
> Perhaps this is more complex. though?
>
> BTW: gawk isn't in the default Raspberry Pi Wheezy distribution, but
> easily obtained with apt-get.
>
> Thanks,
> David