--- Thread.critical
--- Thread.critical = yes_no

    Ǥ֡åɤؤԤޤ󡣥ȥåɤ
    (stop)䥷ʥ˳ޤ줿ˤϡưŪ 
    false ˤʤޤ

    Thread.new ˤꥹåɤˤϤ
    Υåɤϼ¹ԤޤޤThread.pass ˤ
    Ūؤ뤳ȤǤޤ

    yes_no ֤ޤ

    ((**)): I/O  GCĥ饤֥꤬ȤΥե饰̵뤵
    뤳Ȥ⤢ޤ¾ԤˤϤΥ᥽åɤ餺 
    Mutex  Monitor Ȥ٤Ǥ

