The groff package installs a custom
${PREFIX}/share/groff/site-tmac/mdoc.local file.

It has:

.ds volume-operating-system NetBSD

and

.ds operating-system NetBSD\~1.6


If these are not set then it will default to "BSD".

I'd like to suggest that this be customized per the local operating system
that the package was built under.

For example, it doesn't make sense for a manpage unrelated to NetBSD to
say "NetBSD" in the header or footer on a system that is not NetBSD.

I'd like to suggest that the textproc/groff/files/mdoc.local file is
configured via a sed expression.

Have some OS_NAME that can be defined in mk.conf for the
operating-system definition.

If not set, then:

On any *BSD, define OS_NAME as "${OPSYS} ${OS_VERSION}".

On Linux, just use "${OPSYS}".

On other Unix maybe just use "${OPSYS}" too.

For the volume-operating-system definition, just use ${OPSYS}.

(Searching google, I see that a few people have complained about the
groff default of "BSD" on non-BSD systems.)

Any comments?

I can quickly provide a patch for this ...

   Jeremy C. Reed
   http://bsd.reedmedia.net/