Unfortunely Aix and HP-UX servers were out of my control, thus scripts had to stay POSIX compatible for anything that had to run across all our servers, or written in Perl.
Get off my lawn! ;)
It's interesting to say that it's "just another UNIX flavour" when the most common flavours today all have some form of package management.
Two Linux distros, both derived from CentOS Linux, have also held certification in the past.
Whether an OS is a UNIX™ or not is nothing to do with whether it is based on AT&T code and has not been since Novell bought AT&T Unix Labs and donated the trademark to the Open Group in 1993. For three decades, whether it's a Unix or not depends solely on whether it passes Unix compatibility testing.
Linux is a Unix and so is macOS.
(1) crazy command options (it only takes one or two to ease your workflow over the what the system distro supplied, plus the same behavior for the same flags across platforms)
(2) the lawsuit (probably an understatement - it was Serious back then)
Edit: added "usage" for clarity, s/statment/statement
the tools have made big strides over the last few decades, so it's nowhere near like it used to be back then
Really cool looking project - looking forward to trying it out.
I got into the habit of immediately installing gtar on any Solaris box I had root on (damn the leading "/" in the archive).
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The 2nd worst part was dealing with SunOS and HP/UX at work and Ultrix outside of work. Worst part was not grokking why MS-DOS wouldn't buffer keystrokes the few times I was exposed to it.
At least in nixpkgs it's easy to reference the right version explicitly for each context, but everything else is a just guessing.