Debugger in an iPhone app session not launched from tapping a springboard icon

I'm trying to debug an issue that only occurs when my iPhone app receives a push notification.

The trouble is I can't figure out how to get a debugger, or even view any NSLog output, when my app is launched in this way. Xcode gives me a debugger and the gdb console when it launches an app for me开发者_运维百科.

So how do I run my app in the debugger when Xcode does not launch my app for me?

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Asked and answered at Debugging App When Launched by Push Notification

See also the Apple documentation at http://developer.apple.com/mac/library/documentation/DeveloperTools/Conceptual/XcodeProjectManagement/230-Defining_Executable_Environments/executable_environments.html#//apple_ref/doc/uid/TP40002698-CJBICGJI