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from __future__ import print_function
import threading
import Pyro4
import bouncer
abort = False
def PyroLoop(daemon):
daemon.requestLoop()
def main():
global abort
daemon = Pyro4.Daemon()
server = Pyro4.Proxy("PYRONAME:example.deadlock")
bounceObj = bouncer.Bouncer("Client")
daemon.register(bounceObj) # callback object
# register callback on the server
server.register(bounceObj)
# Now register server as 'callback' on the bounce object in this client
# note: we're using the same proxy here as the main program!
# This is the main cause of the deadlock, because this proxy will already
# be engaged in a call when the callback object here wants to use it as well.
# One solution could be to use a new proxy from inside the callback object, like this:
# server2 = server.__copy__()
# bounceObj.register(server2)
bounceObj.register(server)
# create a thread that handles callback requests
thread = threading.Thread(target=PyroLoop, args=(daemon,))
thread.setDaemon(True)
thread.start()
print("This bounce example will deadlock!")
print("Read the source or Readme.txt for more info why this is the case!")
print("Calling server...")
result = server.process(["hello"])
print("Result=", result) # <--- you will never see this, it will deadlock in the previous call
if __name__ == '__main__':
main()
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