5382 Mutex mu1;  variable
5397   mu1.Lock();  in Worker()
5401   mu1.Unlock();  in Worker()
6688 Mutex mu1;  // This Mutex guards var.  variable
6693   MutexLock lock(&mu1);  // Correct Mutex.  in Thread1()
6985 Mutex mu1;  // Protects PTR.  variable
6991   MutexLock lock1(&mu1);  // Protect PTR.  in Writer1()
6997   MutexLock lock1(&mu1);  // Protect PTR.  in Writer2()
7044 Mutex mu1;  // Protects PTR.  variable
7050   MutexLock lock1(&mu1);  // Protect PTR.  in GoodWriter1()
7056   MutexLock lock1(&mu1);  // Protect PTR.  in GoodWriter2()
7061   MutexLock lock1(&mu1);  // Protect PTR.  in GoodReader()