Use correct OpenSSL thread safety macros on OS X (closes #209) Create an Autoconf test to determine if pthread_t is a pointer or scalar type, and use the appropriate CRYPTO_THREADID_set macro based on the result.

fun main () : transaction page = return <xml>
  {[case String.split "abc{" #"{" of
        None => "!"
      | Some (pre, post) => pre ^ post]}
</xml>