Looking up more about howl a few remarks:
– Howl apparently was a fork of Apple’s rendezvous/bonjour/mDNSResponder and has the same APSL license suplemented by a BSD License for their own parts
– The APSL is a license approved by the Free Software Foundation as a free software license. See here: http://www.gnu.org/philosophy/apsl.html (I know they remark that they discourage using it because it allows use in proprietary applications but if you ask me they are only being pedantic.)
So, I don’t really see the problem with using Apple’s rendezvous/bonjour/mDNSResponder. Especially as it is available for many platforms. I understand you prefer not to link it in but it is THE zeroconf framework so one should be able to use it.
Reading about howl I don’t see the point of why they made it even. A fork of Apple’s rendezvous/bonjour/mDNSResponder? What on earth were they thinking?
So as howl is going the way of the Dodo and Avahi is up and coming but for now only on Linux (as I understand it), I for one would like to compile my mt-daapd against Apple’s mDNSResponder (installed separately through pkgsrc).
So a simple –enable-bonjour configure switch would be welcome.