PPC info

[Jeremy Buchmann <buchmann@xxxxxxxxxx>]

Hello,
    I am trying to get OI to compile on my G3 Powerbook which runs LinuxPPC
2000.  I have run into the DGL_NTOH_* macros which eventually led me to
machine.h.  I think I can add a section there for the PPC architecture, but
I haven't been able to figure out where the machine types are initally
defined.  For example, the entry in machine.h for i386 says 

#ifdef __i386__
..
#endif

My question is where is __i386__ initially defined?

Jeremy Buchmann
buchmann@xxxxxxxxxx