To round off this chapter, we present a quick look at two interesting technologies: timers via the file abstraction model and watchdog timers. These sections are not covered in detail; we leave it to the interested reader to dig further.
A quick mention
Timers via file descriptors
Do you recall a key philosophy of the Unix (and, thus, Linux) design that we covered in Chapter 1, Linux System Architecture, of this book? That is, everything is a process; if it's not a process, it's a file. The file abstraction is heavily used on Linux; here, too, with timers, we find that there is a way to represent and use timers via the file abstraction.
How is this done? The timerfd_* APIs provide the required abstraction. In this...