rb_fiber_transfer  735 cont.c         VALUE rb_fiber_transfer(VALUE fib, int argc, VALUE *argv);
rb_fiber_transfer  742 cont.c             rb_fiber_transfer(return_fiber(), 1, &value);
rb_fiber_transfer  902 cont.c             return rb_fiber_transfer(return_fiber(), argc, argv);
rb_fiber_transfer  961 cont.c             return rb_fiber_transfer(fib, argc, argv);