gnome-calculator --version (return code: 0)
gnome-calculator 3.18.3
gnome-calculator --help (return code: 0)
Usage:
gnome-calculator [OPTION...]
Help Options:
-h, --help Show help options
--help-all Show all help options
--help-gapplication Show GApplication options
--help-gtk Show GTK+ Options
Application Options:
-s, --solve=equation Solve given equation
-e, --equation=equation Start with given equation
-v, --version Show release version
--display=DISPLAY X display to use