Share GPS
Android app for sharing GPS data with mapping applications

GPSD is a service daemon that can monitor GPS receivers and provide the data for multiple clients. It normally provides client data on port 2947. See the website here: Newer versions of GPSD allow for using TCP/IP connections to NMEA data sources including Share GPS. Follow below for setup.

  1. Obtain these packages or equivalent for your distribution:
    • gpsd - GPS daemon, can connect to TCP sockets
    • gpsd-clients - Helper programs for gpsd that can help with troubleshooting problems
  2. Make sure you have created a TCP/IP connection in Share GPS.
  3. Before testing with GPSD, let's use netcat to be sure the strings are coming through. If Share GPS is a TCP/IP client, setup netcat to listen (in this example port 50000 is used):

    nc -l 50000

    If Share GPS is a TCP/IP server, setup netcat to connect (but make sure Share GPS is started and listening first!). The IP address of the phone is used below.

    nc 50000

    Share GPS should now indicate connected. If it does, but no data is seen, then try setting 'Create NMEA in settings and try again
  4. Ctrl-c to get out of netcat. Now test that GPSD can connect to Share GPS. Let's try and kill any running gpsd:

    killall gpsd

  5. Start GPSD in debug mode and test it out. If running Share GPS as a server, change localhost in the following command to the IP address of the phone (use port setup in Share GPS, in this case 20175):

    gpsd -D5 -N -n -b tcp://localhost:20175

    You should see some connection info followed by the NMEA strings.

    If you are using a RedHat variant and saw something with selinux popup or were using a Debian variant and saw it come up and complain about not being able to bind to the TCP ports, see the troubleshooing section.

  6. Ctrl-C to get out of gpsd. Now run gpsd in the mode you would normally run in.

    gpsd -b -n tcp://localhost:20175

    You will be back at a command prompt as GPSD will run in the background.
  7. Share GPS should indicate Connected at this point as the -n switch tells GPSD to connect immediately. Try one of the clients to ensure that works. Use 'xgps' or 'cgps' and ensure it is getting NMEA data.
  8. Now you can connect the GPSD client of your choice. OpenCPN is an example or Navit for navigation. If wanting to use Google Earth try this python script with the desired kml file specified.

    python ./gps.kml

Troubleshooting Issues

  1. For RedHat variants, I had issue with selinux blocking gpsd from using tcp ports. Whenever I tried to run gpsd, it would pop up a window and give me the option to add a rule allowing it, and I did that. The other option would be to just disable selinux all together. Be sure you understand the consequences before you do that (do the following as root):

    sed -i 's/enforcing/disabled/g' /etc/sysconfig/selinux


  2. For Debian variants, I had issues with it binding to tcp ports. Couldn't figure it out, so I just rebuilt from source as opposed to using the packages. That worked

    sudo apt-get remove gpsd gpsd-clients

    sudo apt-get build-dep gpsd


    or just do a git clone of the latest

    cd gpsd-3.15;sudo scons;sudo scons install

    It should build and install gpsd. Now go back and try again.