I2C_mutex.py 文件源码

def acquire(self):
        if self.mutex_debug:
            print("I2C mutex acquire")

        acquired = False
        while not acquired:
            try:
                self.DexterLockI2C_handle = open('/run/lock/DexterLockI2C', 'w')
                # lock
                fcntl.lockf(self.DexterLockI2C_handle, fcntl.LOCK_EX | fcntl.LOCK_NB)
                acquired = True
            except IOError: # already locked by a different process
                time.sleep(0.001)
            except Exception as e:
                print(e)

        if self.mutex_debug:
            print("I2C mutex acquired {}".format(time.time()))