# # You can does something in here # # L.unlock (lock_name) If __name__ = = "__main__": Main ()In the main function, l.lock (Lock_name, 10), 10 is the time of the timeout is 10 seconds, if 10 seconds also can not get the lock, return, perform the subsequent operation. In this demo, where you mark Todo, you can place the logic of the consumer taking messages from the job table. That is, dividing lines above:3. Assume that there are multiple consumer processes, taking queued information from the
time is 10 seconds, if the 10 seconds can not get the lock, return, perform the following operation.In this demo, where you mark Todo, you can put the logic for the consumer to take messages from the job table. That is, the split line above.
2. Assuming that there are multiple consumer processes that take queued information from the job table, the actions to be taken are as follows:
SELECT * from jobs where job_status=0 the order by ID ASC limit 1;
Update jobs set Job_status=1 where id
Serial communication Routines
Through the above exercises, the STM32 project development has a visual impression, the next attempt to operate the serial port RS232.
1. Target Requirements:
Turn on the serial port 1, listen to the host computer (using the PC serial test software) sent information, and then delivered to the serial port 1.
2. Create a project
A) disabling Finsh and console
b) By default, the project file contains Finsh, which uses COM1 to communicate, and the console output (rt_kp
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