gifbg(1) on Linux
The text ff0087b683b4, as Debian 4.0 (Etch), Debian 3.1 (Sarge), Debian 3.0 (Woody) shipped it.
Generate a single-color test pattern GIF with gradient.
Flags it lists
-
-M -
-d -
-h -
-l -
-m -
-q