xterm -version (return code: 0)
XTerm(322)
xterm --help (return code: 1)
xterm: bad command line option "--help"
usage: xterm [-/+132] [-C] [-Sccn] [-T string] [-/+ah] [-/+ai] [-/+aw]
[-b number] [-/+bc] [-bcf milliseconds] [-bcn milliseconds] [-bd color]
[-/+bdc] [-bg color] [-bw number] [-/+cb] [-cc classrange] [-/+cjk_width]
[-class string] [-/+cm] [-/+cn] [-cr color] [-/+cu] [-/+dc]
[-display displayname] [-e command args ...] [-fa pattern] [-fb fontname]
[-/+fbb] [-/+fbx] [-fd pattern] [-fg color] [-fi fontname] [-fn fontname]
[-fs size] [-/+fullscreen] [-fw fontname] [-fwb fontname] [-fx fontname]
[%geom] [#geom] [-geometry geom] [-help] [-/+hm] [-/+hold] [-iconic]
[-/+ie] [-/+im] [-into windowId] [-/+itc] [-/+j] [-/+k8] [-kt keyboardtype]
[-/+l] [-/+lc] [-lcc path] [-leftbar] [-lf filename] [-/+ls] [-/+maximized]
[-/+mb] [-mc milliseconds] [-/+mesg] [-/+mk_width] [-ms color] [-n string]
[-name string] [-nb number] [-/+nul] [-/+pc] [-/+pob] [-report-colors]
[-report-fonts] [-rightbar] [-/+rv] [-/+rvc] [-/+rw] [-/+s] [-/+samename]
[-/+sb] [-selbg color] [-selfg color] [-/+sf] [-sh number] [-/+si] [-/+sk]
[-sl number] [-/+sm] [-/+sp] [-/+t] [-ti termid] [-title string]
[-tm string] [-tn name] [-/+u8] [-/+uc] [-/+ulc] [-/+ulit] [-/+ut] [-/+vb]
[-version] [-/+wc] [-/+wf] [-xrm resourcestring] [-ziconbeep percent]
Type xterm -help for a full description.