Nemo's work from uniformed back in 2006 on mach programming.
Updating the code to 10.10 for a mental exercise and to learn mach programming.
Chapter 7 is where it really starts from a programming POV.
To see the example working:
On 10.10:
gcc -o chapter_7 chapter_7.c
brew install nasm
nasm -f macho64 test.asm -o test.o && ld -e _main -macosx_version_min 10.8 -arch x86_64 test.o -lSystem
./a.out &
sudo ./chapter_7 [a.out pid]
[snip output]