A fuse implementation would be good enough today though. You're not doing actual production work on htfs today no matter how special the circumstances.
...and did anyone ever automate parsing the divvy partition table?
I confess I have never productively used either but have destructively used fsck.
Someone is, apparently. Some shop called Xinuos apparently bought part of the corpse (the not lawsuit obsessed, not fraud committing part, presumably) and is still selling SCO OpenServer and Unixware. That's some serious dead-ender computing. But hey...people still run OS/2 in production.
Divvy...haven't thought about that in not long enough.
In the (far) future, just use a past distro to see them. Removal now wipes functionality from the market very, very slowly.