Imported from /home/lorry/working-area/delta_python-packages_posix-ipc-tarball/posix_ipc-0.9.8.tar.gz.HEADposix_ipc-0.9.8master

1 files changed, 45 insertions, 0 deletions

diff --git a/demo3/one_shot_signal.py b/demo3/one_shot_signal.py
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+# Python modules
+import time
+import signal
+
+# 3rd party modules
+import posix_ipc
+
+# Utils for this demo
+import utils
+
+
+MY_SIGNAL = signal.SIGUSR1
+
+
+def handle_signal(signal_number, stack_frame):
+    message, priority = mq.receive()
+    
+    print ("Ding! Message with priority %d received: %s" % (priority, message))
+    
+
+
+# Create the message queue.
+mq = posix_ipc.MessageQueue(utils.QUEUE_NAME, posix_ipc.O_CREX)
+
+# Request notifications
+mq.request_notification(MY_SIGNAL)
+
+# Register my signal handler 
+signal.signal(MY_SIGNAL, handle_signal)
+
+# Get user input and send it to the queue.
+print ("Enter a message:")
+mq.send(utils.get_input())
+
+# The signal fires almost instantly, but if I don't pause at least 
+# briefly then the main thread may exit before the notification fires.
+print ("Sleeping for one second to allow the notification to happen.")
+time.sleep(1)
+
+print ("Destroying the message queue.")
+mq.close()
+# I could call simply mq.unlink() here but in order to demonstrate 
+# unlinking at the module level I'll do it that way.
+posix_ipc.unlink_message_queue(utils.QUEUE_NAME)
+