Als Tipp Read-Only Disk-Images beschreibbar zu öffnen, taugt die Methode natürlich wunderbar für Disk-Images mit Undo-Funktion:
I’ve recently found that OS X now supports mounting compressed and other read-only types as read-write with the use of a shadow file. For example:
% hdiutil attach oed.dmg -shadow /tmp/oed.shadow -noverifyNot only does this save me about 2 gigabytes of drive space, but it lets me avoid worrying about cleanly saving state from VirtualPC, since I can just ditch the shadow file, and go back to my clean version instantly.