nexos wrote:
A good book on OS theory is "Unix Internals" by Uresh Vahalia. It explains process management, threading, SMP based scheduling and synchronization, and other things, using 4.4BSD, SVR4, Solaris 2.x, Mach, and Digital UNIX all as examples.
Second that recommendation. An excellent book.
A good book on the practicalities of the POSIX interface is "Advanced Programming in the UNIX Environment" by Stevens/Rago. I have the 2nd ed. which includes POSIX.1-2001 updates. The books not only explains how to use the POSIX interfaces, but also presents them in the context of other interface definitions such as X/Open and extensions provided by FreeBSD/Linux/Solaris.
The latest edition dumps the STREAMS chapter (as it's obsolete and not supported outside of SysV) and replaces it with an asynchronous I/O chapter, but I have not got that edition. I shall look out for a cheap copy on ebay.
If you want to provide a POSIX interface to your OS, this books is a good place to start.