I just checked in a first attempt at an interface for DNS Service Discovery in Pike 7.7. This lets Pike programs register services so that Rendezvous/Zeroconf-aware applications on the same network can see them. For example, I plan on using it to announce web servers and have them show up as Safari bookmarks automatically.
The current implementation is designed to work with Mac OS X 10.3 or later as well as Linux (using libhowl). However, I don't have a Linux machine with the developer package of libhowl installed so I'm sure some tweaks will be needed for it to compile correctly.
A natural step forward would be to design a Protocols.DNS_SD.Browser class next. This can be a bit trickier depending on what type of API the high-level code should have (e.g. async callbacks or just a snapshot of the currently available services). If anyone feels like helping out it would be great!
(BTW, thanks to Grubba for adding the missing testsuite.in to fix the yellow blupps in Xenofarm.)