ppmcie --version (return code: 0)
ppmcie: Using libpbm from Netpbm Version: Netpbm 10.0
ppmcie: BSD defined
ppmcie: RGB_ENV='RGBDEF'
ppmcie: RGBENV= 'RGBDEF' (env vbl is unset)
ppmcie -h (return code: 1)
usage: ppmcie [-[no]black] [-[no]wpoint] [-[no]label] [-no[axes]] [-full]
[-xy|-upvp] [-rec709|-ntsc|-ebu|-smpte|-hdtv|-cie]
[-red <x> <y>] [-green <x> <y>] [-blue <x> <y>]
[-white <x> <y>] [-gamma <g>]
[-size <s>] [-xsize|-width <x>] [-ysize|-height <y>]