/*
 * Document-method: Bignum#to_msgpack
 *
 * call-seq:
 *   bignum.to_msgpack(out = '') -> String
 *
 * Serializes the Bignum into raw bytes.
 */
static VALUE MessagePack_Bignum_to_msgpack(int argc, VALUE *argv, VALUE self)
{
        ARG_BUFFER(out, argc, argv);
        if(RBIGNUM_POSITIVE_P(self)) {
                msgpack_pack_uint64(out, rb_big2ull(self));
        } else {
                msgpack_pack_int64(out, rb_big2ll(self));
        }
        return out;
}