I recently committed some changes, albeit to the objc runtime
branch, that changed how header files are referenced from other
header files. For example this:
#import <defobj/DefObject.h>
got changed to this:
#import "DefObject.h"
The reason is due to how frameworks are constructed on Apple (and
GNUstep). For those not familiar, frameworks are a simple directory
wrapper structure that puts a dynamic library, its header files,
documentation, any resource files. Normally on UNIX-like systems,
these are separated in difference directories, e.g. the library goes
in /usr/local/lib, the header files go in /usr/local/include, the
documentation goes in another place as well as the resource files.
The nice thing about frameworks is because everything is wrapped up
together, it is easy to copy, distribute, move, etc., the framework
around and it always has everything together.