# Tweet by [@keefmoon](http://twitter.com/keefmoon) on 2010-08-22 08:34:41 > [!INFO] Archived from [original tweet](http://twitter.com/keefmoon/status/21815971641) In reply to: [@andiih](http://twitter.com/andiih/status/21814883397) @andiih I'm trying to save to Core Data in an NSOperation, while providing a MapView based on Core Data info. Trying to use NSLock.