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POCatch all exceptions and then close Com port
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copied!<p>I'm modifying a non-trivial program (with 2 threads) that sends and receives data down a serial connection. Quite often, because of an unexpected error (or bad coding on my part :) ) the program terminates and the COM port is left open. On next subsequent run, I then get an error when attempting to open the COM port. I would like to try and full mitigate against this happening and make sure that no matter where an error occurs - a piece of failsafe code is run and attempts to close the COM port.</p> <p>Can I get away with wrapping the whole program in one try/except/finally block or will I have to micro-manage each thread/class? regards Simon</p> <p>Edited code if that helps</p> <pre><code>#usual python imports etc ... board = pyfirmata.Arduino("COM26", baudrate=57600) # Replace COM26 with your Arduino port ... #vairable initilistation class MyError(Exception): def __init__(self, value): self.value = value def __str__(self): return repr(self.value) class ScratchSender(threading.Thread): #one of the threads class ScratchListener(threading.Thread): #the other thread #bit of code def cleanup_threads(threads): for thread in threads: thread.stop() for thread in threads: thread.join() if __name__ == '__main__': if len(sys.argv) > 1: host = sys.argv[1] else: host = DEFAULT_HOST cycle_trace = 'start' while True: if (cycle_trace == 'disconnected'): cleanup_threads((listener, sender)) time.sleep(1) cycle_trace = 'start' if (cycle_trace == 'start'): listener = ScratchListener(the_socket) sender = ScratchSender(the_socket) cycle_trace = 'running' listener.start() sender.start() # wait for ctrl+c try: #bit of code #print "motorA val:" , motorA if ((motorA > 0) or (motorB > 0)): #do something else: #just let the threads do their stuff in the background time.sleep(0.1) except KeyboardInterrupt: cleanup_threads((listener,sender)) board.exit() sys.exit() </code></pre>

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