>>1
The important thing to note is that you need support from not only your compiler, but your C library as well.
Both GCC and Clang implement quite a large portion of C11. You can see how much of it they support on these pages:
http://gcc.gnu.org/projects/cxx0x.html
http://clang.llvm.org/cxx_status.html
I don't know of any C libraries that support C11 largely. I don't think glibc has a similar page describing the amount they support, but if you look at the changelogs for their later releases you'll see that they're working on it. If your goal is to write portable code, I'd say that for the time being you'll probably be better off using fork, pthreads, or some cross-platform threading library. DAT THREADING SHIT DONT EVEN HAVE NO PLACE IN DA LANGUAGE DAT DEANIS RICKY LOVED.
>>2 I DONT HAVE A BEARD, I'M GUY L. STEELE'S IDENTICAL TWIN BROTHER. I DRESS LIKE HIM, STYLE MY FUR LIKE HIM, AND DO HEAPS OF OTHER SHIT LIKE HIM EXCEPT FOR DA AUTISTIC OUTBURSTS. UR ONE OF THOSE ISO-WORSHIPPING HYENAS. U SHUD EITHER GO BACK TO MAKING YOUR MODEL OF DA HUMAN ANATOMY WITH UR OBJECT ORIENTED RUBBISH OR GROW SUM BRAINS, REED KERNYAN N RICKY NUMBER 2, DEN REED DA FUKIN STANDARD.
>>5 I THOUGHT I WAS DA ONLY ONE WHO WAS ABLE 2 COMPILE C CODE BY HAND.
>>7 THEN DIS PAGE IS FULL OF DONKEY POOP:
http://en.wikipedia.org/wiki/C99#Implementations