[derleth]

> "c for ruby programmers"

Most, if not all, of this book would be "How To Use Pointers" with large sections on how to structure your code around correctly allocating and freeing memory.

A (fairly brief) appendix would be "Weird Stuff C Programmers Actually Do", for the 'dark corners' stuff that's actually used outside obfuscated code competitions. It might be hard for someone who's actually a C programmer to write this; things stop looking weird after a while.