groff(1) on Linux
The text e2892b3519f7, as Debian 10 (Buster) shipped it.
front-end for the groff document formatting system
Flags it lists
-
--help -
--version -
-C -
-D -
-E -
-F -
-G -
-I -
-K -
-L -
-M -
-N -
-R -
-S -
-T -
-U -
-V -
-W -
-X -
-Z -
-a -
-b -
-c -
-d -
-e -
-f -
-g -
-h -
-i -
-j -
-k -
-l -
-m -
-n -
-o -
-p -
-r -
-s -
-t -
-v -
-w -
-z