XCode newbie question here: If I'm programming in C++ or objective C, and I #include or #import a library; e.g.

#include <iostream>
#import <Cocoa/Cocoa.h>

I'm often not sure where to look for these header files in the directory structure on my Mac. In other development environments, you can right click the included or imported filename and have the option to jump to source. Is there such a feature in XCode?

Also, for the standard C++ libraries and the Cocoa framework, is the source code for the implementation files available, or only the headers together with compiled link libraries?

Thanks!