xmodmap --help
usage: xmodmap [-options ...] [filename]
where options include:
-display host:dpy X server to use
-verbose, -quiet turn logging on or off
-n don't execute changes, just show like make
-e expression execute string
-pm print modifier map
-pk print keymap table
-pke print keymap table as expressions
-pp print pointer map
-grammar print out short help on allowable input
- read standard input