Sortie, would you share what POSIX reference you used for the implementation? I wanted to read and understand it for a while, but I never made through the only one I found [1]. Maybe there are alternative sources?
I use that POSIX 2008 edition myself, and the PDF edition that I got through my university library subscriptions. I simply look up interfaces and headers in it. It's not a gentle introduction though to POSIX programming. But if you know the basics, it's useful to look up in. I generally use the http://wiki.osdev.org/Cross-Porting_Software method when porting new stuff, that is, I just cross-compile it. I see what doesn't compile, look it up in POSIX, and implement it.