hdiutil attach /tmp/Sierra.cdr.dmg -noverify -mountpoint /Volumes/install_sierra Use code with caution.
If you are using the ISO to restore a physical Mac, you can burn the image directly to a USB flash drive (minimum 8 GB capacity). On a Mac via Terminal: Plug in your USB drive. Open . macos-sierra-10.12.6-french.iso
(where 17 = year 2017). Install, then reset time. hdiutil attach /tmp/Sierra