55   int errorcode = pthread_mutexattr_init(&attr);  in MutexImpl()  local
56   assert(errorcode == 0); (void)errorcode;  in MutexImpl()
61   errorcode = pthread_mutexattr_settype(&attr, kind);  in MutexImpl()
62   assert(errorcode == 0);  in MutexImpl()
65   errorcode = pthread_mutex_init(mutex, &attr);  in MutexImpl()
66   assert(errorcode == 0);  in MutexImpl()
69   errorcode = pthread_mutexattr_destroy(&attr);  in MutexImpl()
70   assert(errorcode == 0);  in MutexImpl()
91   int errorcode = pthread_mutex_lock(mutex);  in acquire()  local
92   return errorcode == 0;  in acquire()
101   int errorcode = pthread_mutex_unlock(mutex);  in release()  local
102   return errorcode == 0;  in release()
111   int errorcode = pthread_mutex_trylock(mutex);  in tryacquire()  local
112   return errorcode == 0;  in tryacquire()