C halps

How do I check what type of variable a variable is?

Something like;
if (typecheck(foo,int))
  {
  /* lol */
  }

>>9
FUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUCK!!!

Well, how about storing the byte at the value returned by malloc - 1?  Is that writable or not?  (I assume yes.)

That's what I would do then.