Around 2000 or so, I used to work in tech support for a software company who had like 5000 Windows-based customers and 5 running Solaris. My boss chose me to learn Solaris when the previous “expert” left. I bought this book and started hacking. Good times!
He wrote a bunch of these books, they’re still quite useful for foundational and historical knowledge on the subjects.
Another book on the history of unix is UNIX: A History and a Memoir from Kernighan. It was a joy to read.
Adding it to my reading list, thanks!