Objective-C Fundamentals

Debugging techniques
This chapter covers
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Creating a buggy application
Using NSLog
Controlling leaks with Instruments
Detecting zombies
There’s nothing worse than being close to releasing a new application and in your
final once-over finding a particularly nasty application crash that seems to have no
obvious cause. Even during day-to-day development of your application, it’s
unlikely that you’ll write perfect code the first time around, so understanding how
to debug your application in the Xcode environment is an important skill.
The Xcode environment integrates a large number of debugging and code
analysis tools, but as usual, their true power is only unleashed if you know which
tool to use and how and when to use it. A common complaint for new Objective-C
developers who are used to managed environments such as C# or Java is that memory
management and correct handling of object retain counts (retain, release,
autorelease, and dealloc message handling) is hard; so Xcode provides extensive
support for detecting and diagnosing memory-related errors.
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