Unix vs Linux

Unix was started by Ken Thompson, Dennis Ritchie and some other engineers including Brian Kernighan back in the early 1970s. It has a long and illustrious history. But then Linux came along and things changed. How is Linux different to Unix? Are they the same thing?


Linux vs. Unix: What's the difference?
Dive into the differences between these two operating systems that share much of the same heritage and many of the same goals.
Linux vs. Unix: What's the difference?
https://opensource.com/article/18/5/differences-between-linux-and-unix

 

Here's the family tree:



https://en.wikipedia.org/wiki/History_of_Unix

 

Now, Windows has Linux subsystem as well. I'd prefer Ubuntu distros than pure Linux/UNIX kernel.

 

Yeah, if you wanted to get into OS compatibility layers and virtualization the chart would have to be a loop or venn diagram...

Ubuntu is a distro of GNU/Linux, and is a Debian derivative... getting into a Linux distro family tree is an exercise in futility though. "Pure" Linux would be rolling your own as in Linux From Sratch, and bootstraping an OS can be useful as a learning exercise.

 

Although LInux contains none if Minix's code, I feel the diagram above should show that Linux was inspired by Linus wanting a bigger / better version of Tanebaum's Minix.

The first postings of Linux appeared in comp.os.minix. In fact Linus posted at one time, "... This is also when I started to get serious about megalomaniac ideas to make 'a better Minix than Minix.' I was hoping I'd be able to recompile gcc under Linux someday." https://docstore.mik.ua/orelly/linux/run/ch01_02.htm

 

I won't say that the difference is academic, but considering how fragmented the UNIX world became (what with the various BSD's and System V derivatives), how much of the GNU userland is used by e. g. Solaris, and the diversity of Linux, it's hard to know how to break it down. Just about the only thing clearly distinct is the kernel.

You'll find a Linux kernel in all manner of unexpected places, from embedded controllers to Android. The Android userland (even ignoring the UI) isn't very much like any desktop or server Linux out there, but desktop/server Linux distributions are very similar (except for the system management layer) to commercial UNIX platforms like Solaris. Oh, and that system management layer varies between old line Linux distributions: Debian-based distributions are quite different from RPM-based ones, and then there's always Slackware and Gentoo, which are different altogether. And sure, most Linux distributions now use systemd rather than sysvinit, but then again Solaris doesn't use System V init either; it uses SMF, which has more in common with systemd than with traditional init. And Solaris packages are built from specs that look rather much like RPM specfiles.

Confused, much?