[gpsd-users] MSL-WGS84 separation

[j8pm0614]

I need an altitude-output in the WGS84 reference system. As it seems I can
only read the altitude as above mean sea level. So I wanted to read the
separation from the GPS device (ublox 6) that should be available in the
struct gps_data_t, but the value returned by the GPSD is always zero for
the separation. I checked the data-stream coming from the GPS and there
the separation appeared correctly in the $GPGGA line of the NMEA-output:
$GPGGA,120521.00,4333.88682,N,00128.90257,E,2,08,1.21,155.3,M,48.5,M,,0000*52
I use a function double wgs84_separation(double lat, double lon) instead,
but it seems to be not very accurate. This is how I wanted to get the
separation:

> static struct gps_data_t gpsdata;

> double separation = gpsdata.separation;

this returns 0, while for instance gpsdata.fix.latitude returns the
correct value.
What could be the problem here?

dgps2ivy.c
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