Doug starts with a short overview of real time embedded systems and Linux providing a good background for the reader even if the topics are new. The book then introduces BlueCat Linux but it does not waste time on the details of Linux in general. There are plenty of books for that.
What I like is how he gets down into sample applications with enough information to understand what is going on but leaving the details that can be found in application code on the CD. This leaves plenty of room to examine topics like real-time scheduling, POSIX threads and RTAI. RTAI (RealTime Application Interface) is a split, hard real time platform. The chapter covering this is good but you need to download support from the RTAI site if you want to experiment with it. Doug does a good job of describing when you can get along with just BlueCat and when RTAI is needed. An appendix provides the RTAI API. Very useful.
I would have liked more detail on aspects such as BusyBox, a compact shell environment, that often finds a home on headless systems. Of course, this does leave space for a chapter on Eclipse, the open source IDE (integrated development environment).
If you are considering Linux as an embedded platform and the approach is new to you then this will be an invaluable introduction with a hands-on, PC-based option.
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