# Kirk McCusick's Overview Course on FreeBSD
symmetric multithreaded kernel
kernel is build out of 2 distinct pieces
- system for distributing processes OR purveyor of processes
- giant i/o switch
process has 4 components:
- CPU Time
- Asynchronous Events
- interrupt??
- (divide by 0 causes some kind of) hardware trap??
- Memory
- I/O descriptors
steps in compiling a program preprocessor - compiler 1st pass - 2nd pass of compiler - assembler - loader - executable
Unix brought 2 new breakthrough concepts:
- commodity processes as a fundamental service
- uniform descriptor space(for i/o descriptors)
# Reading links
https://www.jeremymorgan.com/blog/freebsd/freebsd-developer-2020/ https://www.unixsheikh.com/articles/freebsd-is-an-amazing-operating-system.html