I can add five pennies how it works in Defold Kit, since the topic allows. Maybe it will be as useful for someone else.
Windows
"FULL_PATH_TO_YOUR_PROJECT_FILE"
macOS
Check to see if Defold is already running:
pgrep -l Defold | awk '{ print $2 }'
Open an existing process:
osascript -e 'activate application "Defold"'
Create a new process:
open 'Applications/Defold.app' 'FULL_PATH_TO_YOUR_PROJECT_FILE'
Linux
But not sure if it works everywhere though… maybe it’s no better than xdotool
, I just don’t know.
xdg-open "FULL_PATH_TO_YOUR_PROJECT_FILE"