emulating termux-location

to bodge surplus on wheels (s+ow) on non-Termux systems

termux-location, part of Termux:API, gets the device's location via android apis and returns a json response through stdout:

{
  "latitude": 1.3277513,
  "longitude": 103.678317,
  "altitude": 51.6298828125,
  "accuracy": 48.46337890625,
  "vertical_accuracy": 38.4659423828125,
  "bearing": 0.0,
  "speed": 0.0,
  "elapsedMs": 28,
  "provider": "gps"
}

see https://wiki.termux.com/wiki/Termux-location for more information

implementing for surplus on wheels (s+ow)

s+ow will call the command a total of six times, being three pairs of parallel $LOCATION_CMD -p "network" and $LOCATION_CMD -p "gps" invocations, before deciding after exhausting all six runs on which output to choose, if any command runs were successful

even if somewhere in the termux-location implementation fails, it always (begrudgingly) returns zero. s+ow will treat the invocation of the command as successful if there is any output to the standard output (stdout) stream

implementing for surplus (s+)

s+, when passed --t / --using-termux-location, will consume stdin, parse it as json and then attempt to retrieve the latitude and longitude keys as floating point numbers