The 4.4 BSD book is also available in an updated version for FreeBSD: https://www.pearson.com/us/higher-education/program/Mc-Kusick-Design-and-Implementation-of

The 4.4 BSD book is also available in an updated version for FreeBSD: https://www.pearson.com/us/higher-education/program/Mc-Kusick-Design-and-Implementation-of-the-Free-BSD-Operating-System-The-2nd-Edition/PGM224032.html https://www.pearson.com/us/higher-education/program/Mc-Kusic... ...and there's more: - "xv6: a simple, Unix-like teaching operating system" https://pdos.csail.mit.edu/6.828/2020/xv6/book-riscv-rev1.pdf https://pdos.csail.mit.edu/6.828/2020/xv6/book-riscv-rev1.pd... - Douglas Comer's book "Operating System Design - The Xinu Approach" (https://xinu.cs.purdue.edu https://xinu.cs.purdue.edu) - Gernot Heiser's "Inside L4/MIPS" (https://ts.data61.csiro.au/publications/papers/Heiser:IL4.pdf https://ts.data61.csiro.au/publications/papers/Heiser:IL4.pd...)