background process in iphone sdk?

I want to do local push Notification (giving alert) when the user comes in particular locations(in ran开发者_StackOverflow中文版ge).is it possible to do it? any example and tutorial please?

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I hope it would help : http://iphonesdkdev.blogspot.com/2010/04/local-push-notification-sample-code-os.html

and you can search for pushmebaby for testing push notification in iPhone.