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¡¡¡¡2. LatchÖ»×÷ÓÃÓÚÄÚ´æÖУ¬ËûÖ»Äܱ»µ±Ç°ÊµÀý·ÃÎÊ£¬¶øL ock×÷ÓÃÓÚÊý¾Ý¿â¶ÔÏó£¬ÔÚRACÌåϵÖÐʵÀý¼äÔÊÐíLock¼ì²âÓë·ÃÎÊ
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¡¡¡¡4. LatchÊÇ·ÇÈë¶ÓµÄ£¬¶øLockÊÇÈë¶ÓµÄ
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