This is a beautiful reference to ANSI C and it's totally free. I downloaded this from BeBits.com a while ago. I think the person that posted it is different than the author. Regardless, I sent the author an email letting him know this is up here and I'd like his consent to keep it that way.

A lot of the new standard C++ attempts to prevent you from using some of these C features, but hell they are so cool. I never knew that you could easily do exceptions in pure ANSI C. If you don't believe me take a look at the setjmp.h document. After I read that I made a little C program where I made TRY/THROW/CATCH macros ... it was awesome. And no funny compiler switches to deal with!

There are some problems with a few of the documents. One in particular has an italics tag (<I>) that never ends and results in a whole page or more of jagged text. I think some of the information isn't accurate on all compilers either, but in any case I can't remember what things those were.