The company I consult for made a bunch of enhancements to the FreeBSD kernel for
their product, and now they want me to implement all those enhancements to the
NetBSD kernel.

So the question now is, in what respects do these two kernels differ?
Enhancements were made to the IDE and SCSI drivers, NFS and SMB. They added
file locking and recovery, case insensitive matching to the filesystem,
enhanced user/group, etc.

1. At first glance, the drivers are completely different between the two kernel
   implementation. Even the parameters to functions are different, though the
   function names are identical. Is this correct?
2. Are there any differences between the NFS implementations?
3. How about the standard disk filesystem?
4. Are there differences between the lockd implementations?

While porting an application, I noticed some minor differences that even a
simple program runs into.

5. libutil.h on FreeBSD is named util.h on NetBSD. Why? Are there other includes
   that have changed names or semantics?
6. the include file /usr/share/mk/bsd.prog.mk includes bsd.sys.mk which adds
   the -Werror compile option. Does it make sense to turn warnings into error
   for general applications? Are user applications not supposed to use
   bsd.prog.mk?

Valentin