Re: [gpsd-dev] GPSD Shared Memory Flags

[Franco Diego]

Hello guys,

I sent an email before with attachment and was scrubbed by the email server. I'm
checking the "set" flags in gps_data_t data struct when using shared memory and
I'm getting inconsistencies.

I setup GPSD in a beaglebone and "cgps" module works fine, I'm using the C++
libgpsmm library where I can read GPS position and time through the gps_data_t
data structure, however when it comes to check the "set" flags in gps_data_t,
these flags are not being set for every packet as follows:


-----Shared Memory:

1. For the below packet (retrieved every second), the STATUS_SET is the only
flag on in "set" member of the gps_data_t data structure, and I see that lat,
long, time, etc changes and still no more flags get set in "set" flag.

{"class:":"TPV","tag":"RMC","device":"...."......         

set flag : '0b1000000000'


2. For the below packet ( retrieved every 5 seconds), the "set" member in
gps_data_t data structure is:

{"class:":"SKY","tag":"GSV","device":"...."......

set flag : '0b10000000001000100000000010'


-----Sockets:

1. When I test the code with sockets instead of shared memory,  for the
following packet (retrieved every second), the flags seem to look OK, since they
lat, long, etc flags are set

{"class:":"TPV","tag":"RMC","device":"...."......        

set flag: '0b10000001010011011111111100'


2. For the below packet (retrieved every 5 seconds), the set member in
gps_data_t struct is:

{"class:":"SKY","tag":"GSV","device":"...."......

set flag : '0b10000001011011011111111100'


Do you know why when testing with shared memory why the TIME_SET, LATLON_SET,
ALTITUDE_SET, SPEED_SET, etc set flags in gps_data_t are not being set even
though I'm getting updates on the shared memory (different data every second)?
this works with sockets as shown above.

Thank you!

Diego