${LOCALBASE}/share/mk/bsd.own.mk defines a number of things such as
MANDIR, INFODIR, DOCDIR, etc.

Are they meant to be strictly read-only for pkgsrc, or could pkgsrc want
to write something there?
Are packages supposed to use ${PREFIX}/man, ${PREFIX}/info, and
${PREFIX}/share/doc, respectively, or are there any explicit defines for
these purposes?

Where do I find such giuidelines? 

-- 
Georg Schwarz    http://home.pages.de/~schwarz/
 georg.schwarz@freenet.de   +49 177 8811442