See it here: http://careferencemanual.com/, at its home page.
Or at Amazon here: http://www.amazon.com/Reference-Manual-5th-Edition/dp/013089....
Turn to this book when you have questions. The authors are Harbison and Steele. If you become a C programmer, you will want and need this book. So you may as well get a copy now.
Another (more advanced) book is The C Puzzle Book.
It's older and I'm not sure it's totally up-to-date with the latest version of C. But it's still very valuable. If you finish this book, you will be a C ninja, and it isn't too hard.
K&R is outdated, in my opinion, because it is too skimpy.
It's a funny little book that can keep you busy during compilation time.
And the "C Reference Manual" (http://www.careferencemanual.com/) is the best, up-to-date reference to understand how this small language can be abused.
2. "The Unix Programming Environment" (http://www.amazon.com/Unix-Programming-Environment-Prentice-...) This is a recent find, but covers more application. It's almost a Part 2 of K&R and covers building problems and the Unix signal and file APIs. The examples are in an ancient syntax, but part of the fun is coding them and getting them to compile.
3. "The C Puzzle Book" (http://www.amazon.com/Puzzle-Book-Alan-R-Feuer/dp/0201604612) I found this one day at Fry's, and it's fucking awesome. You can effectively learn C using it without a compiler.
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