"It has partial POSIX compatibility and access to a command-line interface through Bash, although internally it is not a Unix-derived operating system."
From that and just browsing around, it seems to be a vaguely Unix-ish environment; or at least it has more in common with Unices than the CPM/DOS/Windows or other OS families.
HAIKU is basically a clean-room reimplementation of the public (and private) framework modules' APIs and as such doesn't even (really) descend from BeOS-proper at all.
(Avid late-1990s BeOS user, dual PowerPC 603e-133 BeBox owner, HAIKU supporter.)
That's kind of amazing given how rare those were/are. I definitely can't top that, but I had a dual Pentium III machine that ran R5 (and ZETA for a while, which I had problems with) in the early 2000's. That thing seemed faster than the machines I have today. Good times.
I also had a dual PIII-450 machine (alias “Mad Cow”) that dual-booted Windows NT/2K and BeOS R5 (but sadly only displayed B&W 800x600 due to lack of display-adapter driver support) and consequentially was nigh unusable.
Did you ever use that machine for BeShare back in the day? Because that name associated with BeOS really stands out in my memory. Or maybe, were you on Usenet back then?
Sorry for the pointed questions, just trying to sort out where I remember you from. I discovered BeOS a few months before they folded, and managed to buy 5.0 Pro while it was still being sold by GoBe. I still have my disc and book to this day along with the BeOS Bible and Be Advanced Topics, and I recently acquired an old Dell P-III system which runs it flawlessly (I just need to round up a PATA hard drive as its original drive died a noisy death a few hours after I powered it up).
Not all OSes have these same foundational pillars. What I meant to express is that Linux does whereas others (as disjoint as Genera, Windows NT, BeOS Amiga) don't.
Plan 9 was pretty much about taking the "everything is a file" thinking to its logical end point. Meaning that you could even manipulate individual GUI windows via the FS.
I was simply musing that Linux may have taken the concept further than the BSDs while still being "unix". I can't say i ever got the impression that Plan 9 was intended to be posix compatible for instance.