I'm new to NetBSD, so please bear with me.  I need to know what happens
to the files in /etc during an upgrade, since I'll be tracking 1.5_ALPHA
as part of a research effort on log-based file systems.

The INSTALL file for 1.5_ALPHA, in the section titled "Upgrading a
previously-installed NetBSD System", states that "existing configuration
files in /etc are backed up and merged with the new files."  However, a
search of the mail archives indicates that this might be limited to just
preserving the old fstab and copying it back to /etc after the upgrade. 
In any case, the INSTALL file is silent on exactly how the merge takes
place.

I follow FreeBSD, and there are often important changes in /etc --- not
only contents of files, but sometimes changes in what files exist and
where they are located.  So, my questions:

  1)  To what extent is this true of NetBSD?

  2)  What's the best way to examine /etc and
      resolve differences between old and
      upgraded files?  In particular, is there
      anything like FreeBSD's "mergemaster"?

  --Dwight Tuinstra
    tuinstra@clarkson.edu