xmodmap(1) on Linux
The text a7c33b9d5bd1, as Debian 7 (Wheezy) shipped it.
utility for modifying keymaps and pointer button mappings in X
Flags it lists
-
-display -
-e -
-grammar -
-help -
-n -
-pk -
-pke -
-pm -
-pp -
-quiet -
-verbose