Xcode with arduino serial, howto ?

I just spend few month with arduino with windows xp system, and I was quit easy to develop software that were able to read/write serial datas (through usb) with arduino.

I just get an mac book pro comuter with xcode 4.5, and I begin to develop with it (most of my soft are dealing with sound, like plugins, reading/generating smpte time code, etc...)

So from I'm really quit easy with developing softwares, but XCode, cocoa and others libraries are quit new for me. If some one can provide some pieces of code that will allow me to send/receive data from an arduino through my mac book, it would be very kind of him.

I'm talking about realizing objective-c or c++ softwares with graphical interfaces. I don't mind about python, perl or other way of doing it.

Best regards