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New thread blocks the main thread

from threading import Thread
class MyClass:
    #...
    def method2(self):
        while True:
            try:
                hashes = self.target.bssid.replace(':','') + '.pixie'
                text = open(hashes).read().splitlines()
            except IOError:
                time.sleep(5)
                continue
        # function goes on ...

    def method1(self):
        new_thread = Thread(target=self.method2())
        new_thread.setDaemon(True)
        new_thread.start()  # Main thread will stop there, wait until method 2 

        print "Its continues!" # wont show =(
        # function goes on ...

Can it be so? After new_thread.start () the main thread waits until it finishes, why is this happening? I have not provided new_thread.join () anywhere.

The daemon does not solve my problem because my problem is that the main thread stops immediately after starting a new thread, not because the main thread has finished executing.

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2 answers


As written, calling the constructor Thread

calls self.method2

instead of referencing it. Replace target=self.method2()

with target=self.method2

, and the threads will run in parallel.



Note that depending on what your threads are doing, CPU calculations may still be serialized due to the GIL .

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IIRC, this is because the program does not exit until all non-daemon threads have finished executing. If you use a daemon thread instead, it should fix this issue. This answer gives more details on daemon threads:



Daemon Topics Explained

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