gdal_contour(1) on Linux
The text 81a1cbf90e3a, as Debian 9 (Stretch) shipped it.
builds vector contour lines from a raster elevation model
Flags it lists
-
-a -
-b -
-dsco -
-f -
-fl -
-i -
-lco -
-nln -
-off -
-snodata