I read Operating Systems: Design and Implementation in 1988 or 1989, and it was an insightful and pleasing experience. I only wished, at the time, that there was some Unix-like OS that was "free" (for some intuitive value of the word "free", rather than the formal definition, which I hadn't heard of yet at the time). This could have been Minix.
One of the best textbooks I had to read for my degree, back in the 80s. The appendix containg the Minix source code was my first exposure to a large body of well-written C code.
