CS:APP 3rd (64bit) edition http://csapp.cs.cmu.edu/ http://csapp.cs.cmu.edu/ Lectures for it are here: https://scs.hosted.panopto.com/Panopto/Pages/Sessions/Li

CS:APP 3rd (64bit) edition http://csapp.cs.cmu.edu/ http://csapp.cs.cmu.edu/ Lectures for it are here: https://scs.hosted.panopto.com/Panopto/Pages/Sessions/List.aspx#folderID=%22b96d90ae-9871-4fae-91e2-b1627b43e25e%22&maxResults=50 https://scs.hosted.panopto.com/Panopto/Pages/Sessions/List.a... This teaches you C, x86-64 arch, stuff like two's complement integers and floating point, how memory and CPUs work, how the C compiler works (linking stage, preprocessor), and how to write/understand signals and processes, file I/O, network code ect. After that you can just start reading the OpenBSD code and will figure it out or get an Andrew S Tanenbaum book on Operating Systems. Note, if you buy the Pearson Global Edition of CS:APP (it's only 10% the reg price) there's a lot of errata you will have to check. I once got stuck reversing an assembly program into C that did an even/odd parity check because of a print error returning the final XOR'd value & 0 instead of & 1.