Yes, I've wrote sysctlfs (scfs) just as an explorer for sysctl
name space and as very simple sample filesystem. Yesterday, it has been
modified to compile on recent -current. In addition, it demonstrates
(ab)use of VOP_GETEXTATTR().
Cool. I was thinking that since the issue of a sysctl filesystem comes up
every so often, it would be nice to include an implementation as a port. Would
you be interested in making and maintaining a port of your implementation? If
not, I'll probably finish polishing off the one I was writing and do it.
Then, next time it comes up we can just say "see port XXX" :)