gpx(1) on Linux
The text 52c8817ff1b6, as Debian 10 (Buster) shipped it.
G-code to X3G converter
Flags it lists
-
-C -
-F -
-N -
-b -
-c -
-d -
-e -
-f -
-g -
-i -
-l -
-m -
-n -
-p -
-q -
-r -
-s -
-t -
-v -
-w -
-x -
-y -
-z