hdiutil convert /tmp/Catalina.dmg -format UDTO -o ~/Desktop/Catalina.cdr Rename to .iso: mv ~/Desktop/Catalina.cdr ~/Desktop/Catalina.iso Alternative Resources
: sudo /Applications/Install\ macOS\ Catalina.app/Contents/Resources/createinstallmedia --volume /Volumes/Catalina --nointeraction macos catalina 10157 iso download new
hdiutil attach /tmp/Catalina.dmg -noverify -mountpoint /Volumes/Catalina hdiutil convert /tmp/Catalina