[frostmatthew]

It's pretty clear the OP is asking about learning C, not any of the higher level derivative languages you mentioned.

To the OP: while I sadly don't have any resources to recommend I do applaud you for tackling a lower level language like C, I think you'll get a lot out of it. Best of luck!

[czbond]

It's not clear - and many people who've used other languages simply call all derivations "C" - when they're clearly different. Also, if you're going to be a betting person.... is a Ruby person more likely to learn C or Objective C? Right. So I was in fair ground. :)

[slyv]

Heh ;)

For clarification, I was meaning pure C.