Many of the available format options in GPSBabel can themselves take options. While we try to make all the formats do the most sensible thing possible without any extra options; this allows great power and flexibility in the operation of the program.

Suboptions are comma separated and immediately follow the option itself. The available suboptions are listed on the individual format pages. We'll make an example from the section called “Google Earth (Keyhole) Markup Language (kml)” :

gpsbabel -i gpx -f file.gpx -o kml,deficon="file://myicon.png",lines=0 -F one.kml -o kml -F two.kml

This command will read the GPX file file.gpx and create two KML files. one.kml will have the given icon and no lines between track and routepoints. two.kml will be created with the defaults used in the KML writer.

Suboptions for the various formats allow you to change serial speeds, pass arguments to filters, change the type of file written, override icon defaults, and lots of other things. The suboptions for each filetype are documented on the page in this document that describes the option itself.