Quick code that provides the distance between two GNSS coordinates in kilometers and miles. And because whynot? I added a Python3 version. And a JS version. BECAUSE WHY NOT?!?
> ./test
Default coords. argc = 1
distance between 22.400000, 113.900002 and 22.400000, 114.000000:
* 10.280 km
* 6.390 mi
> ./test 22.2 113.9 22.4 114.1
Custom coords. argc = 5
distance between 22.200001, 113.900002 and 22.400000, 114.099998:
* 30.300 km
* 18.830 mi
> python haversine.py
Default coords. argc = 1
Distance between 22.4, 113.9 and 22.4, 114.0:
* 10.28 km
* 6.39 mi
> python haversine.py 22.2 113.9 -22.4 114.1
Custom coords. argc = 5
Distance between 22.2, 113.9 and -22.4, 114.1:
* 4959.34 km
* 3081.59 mi
> js haversine.js
4959.34 km
3081.59 mi