// In io.c the method 'puts' is defined as global function
rb_define_global_function("puts", rb_f_puts, -1);

// rb_f_puts is defined in io.c
static VALUE
rb_f_puts(int argc, VALUE *argv, VALUE recv)
{
    if (recv == rb_stdout) {
        return rb_io_puts(argc, argv, recv);
    }
    return rb_funcall2(rb_stdout, rb_intern("puts"), argc, argv);
}