prep_stdio       8637 io.c               rb_stdin = prep_stdio(stdin, FMODE_READABLE, rb_cIO, "<STDIN>");
prep_stdio       8639 io.c               rb_stdout = prep_stdio(stdout, FMODE_WRITABLE, rb_cIO, "<STDOUT>");
prep_stdio       8641 io.c               rb_stderr = prep_stdio(stderr, FMODE_WRITABLE|FMODE_SYNC, rb_cIO, "<STDERR>");