Re: It will be missed
"it was weird and it required more hacks than aix, Solaris, or irix."
The HPUX Software Porting and Archive Depot (from memory) was your friend if you wanted gnu software — gcc for starters — but a fair bit of other open source software too.
For my sins I worked for roughly a decade in an environment where I was responsible for workstations running a variety of versions of decosf/1 (digital unix, tru64), hpux, irix, sunos (solaris) and aix. The only obvious commonality was they all supported NIS (YP) and NFS. Every version supported at least two file systems and no two bsd ufs derived file systems were compatible.
Some of the oddness was due to the OSF — UNIX International split. DECOSF and HPUX10 had a fair bit in common, while Solaris and Irix shared some commonality.I think only Solaris2 was a system V.4 derivative; hpux10, irix were System V.3; Aix was System III?; DECOSF had a Mach foundation but looked like System V + BSD (which could be said of most Unices.)
Still open source software was rather portable between various Unices - unheard of in other OS. I had ssh v1 running on all the boxen long before any vendor support . When much later postfix appeared, sendmail was quickly consigned to history. ;)
One thing I remember was once you got down to the command line utilities (required for scripting) a lot of the differences were mostly cosmetic.
In the event over a period of two years all the Unix boxen were replaced by inexpensive, faster x86 Linux systems. I still have collection of OS and software cdroms for hardware now only found in a museum or landfill.