问题
I tried to no avail
defaults write com.apple.Xcode ApplePersistence -bool NO
defaults write com.apple.dt.Xcode ApplePersistence -bool NO
The "Ask to keep changes when closing documents" option from 4.2 has been removed, https://discussions.apple.com/message/20435985#20435985.
回答1:
Turn System Preferences -> General -> "Ask to keep changes when closing documents" on.
It's still there as of OS X 10.8.3.
来源：https://stackoverflow.com/questions/15468313/how-to-disable-auto-save-in-xcode-4-6