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Python Error Thread Already Started


When the lock is locked, reset it to unlocked, and return. class threading.Timer A thread that executes a function after a specified interval has passed. more stack exchange communities company blog Stack Exchange Inbox Reputation and Badges sign up log in tour help Tour Start here for a quick overview of the site Help Center Detailed You must re-create the Thread in order to start it again. this contact form

It stops being alive when its run() method terminates - either normally, or by raising an unhandled exception. Lock.release()¶ Release a lock. Once a thread has acquired it, subsequent attempts to acquire it block, until it is released; any thread may release it. A primitive lock is in one of two states, "locked" or "unlocked". http://stackoverflow.com/questions/14293368/restarting-thread-in-python-why-needs-the-instance-to-be-recreated

Threads Can Only Be Started Once Python

If the semaphore is released too many times it's a sign of a bug. My understanding of time.sleep() is during the sleep time everything "stops". Timer Objects 16.2.8.

It's like:: while True: function_name(*arguments) just with a five second delay. When the state is unlocked, acquire() changes the state to locked and returns immediately. more hot questions question feed lang-py about us tour help blog chat data legal privacy policy work here advertising info mobile contact us feedback Technology Life / Arts Culture / Recreation Python Threading Timer Reset Therefore I am working on making a watchdog to check if threads have died and restarting them.

Related 3225What is a metaclass in Python?399Is there any way to kill a Thread in Python?941How to clone or copy a list?533How to use threading in Python?1Restarting Threads in python and Python Run Thread Multiple Times Antsy permutations Which lane to enter on this roundabout? (UK) Was Sigmund Freud "deathly afraid" of the number 62? Ciao, Marc 'BlackJack' Rintsch Jul 6 '07 #2 P: n/a jimxu hmm.. look at this site I can't help but wonder: is it safe, or is it tempting the Gods of parallelism to inflict sudden, multi-threaded death?

Optional Operating System Services » © Copyright 1990-2016, Python Software Foundation. Python Set Of Rules Is Called Does the Many Worlds interpretation of quantum mechanics necessarily imply every world exist? How to flood the entire lunar surfaces? Since notify() does not release the lock, its caller should.

Python Run Thread Multiple Times

If you derive a class from threading.Thread you can add a Thread.__init__(self) at the end of your run method and you'll be able to call start again and it'll automatically reinitialize http://stackoverflow.com/questions/11249217/python-cant-start-a-new-thread If you really don't want to handle the exceptions internally, just store the construction arguments and use them to start a new thread. Threads Can Only Be Started Once Python Lock Objects 16.2.3. Python Restart Thread After Exception The notify() method wakes up one of the threads waiting for the condition variable, if any are waiting.

It arranges for the object's run()method to be invoked in a separate thread of control. weblink Thread Objects 16.2.2. Changed in version 2.6: Added is_set() spelling. The optional size argument specifies the stack size to be used for subsequently created threads, and must be 0 (use platform or configured default) or a positive integer value of at How To Stop Thread In Python

The `Timer`\s would all run the function after five seconds. When it was zero on entry and another thread is waiting for it to become larger than zero again, wake up that thread. Semaphore Example¶ Semaphores are often asked 3 years ago viewed 14147 times active 3 years ago Blog Stack Overflow Podcast #92 - The Guerilla Guide to Interviewing Get the weekly newsletter! navigate here isDaemon()¶ setDaemon()¶ Pre-2.6 API for daemon. 16.2.2.

As join() always returns None, you must call isAlive() after join() to decide whether a timeout happened - if the thread is still alive, the join() Which Of The Below Uses Python Extensively It arranges for the object's run() method to be invoked in a separate thread of control.  Like this:Like Loading... But I am not sure which method to use.

I had initialized the arrays like this: self.producerThreads = self.consumerThreads = [] Both arrays referred to the same memory.

Here is the relevant code: # background processes t = threading.Timer(5.0, function_name, [arguments]) while True: # Do background processes run inside while loop? Because the threads can only be started once. What does "they are facing their chest and shoulder" mean in this paragraph? Web Application Framework Of Python Join them; it only takes a minute: Sign up Python Terminated Thread Cannot Restart up vote 5 down vote favorite 1 I have a thread that gets executed when some action

Why do jet engines smoke? The func will be passed to sys.setprofile() for each thread, before its run() method is called. Note that some platforms may have particular restrictions on values for the stack size, such as requiring a minimum stack size > 32kB or requiring allocation in multiples of the system his comment is here The flag can be set through the daemon property.

At best, you'd get a different wrapper around the same OS-level thread object, so you'd fool Python into not noticing that you're trying to do the illegal, possibly segfault-inducing things it However, in my application, there are background processes that must be running continuously during the five second interval. They are never deleted, since it is impossible to detect the termination of alien threads. share|improve this answer edited Jan 12 '13 at 14:10 answered Jan 12 '13 at 12:43 Ellioh 3,0711024 add a comment| up vote 1 down vote See here: http://docs.python.org/2/library/threading.html#threading.Thread.start It must be

And conceptually, it doesn't make any sense. Their resources (such as open files, database transactions, etc.) may not be released properly. The static methods of Java's Thread class, when implemented, are mapped to module-level functions. I hope it will explain how threads and sleeps interact.

additionally, you should not that you cannot restart a thread once it has finished execution: you have to recreate the thread object for it to be started again. threading.stack_size([size])¶ Return the thread stack size used when creating new threads. Once the signal has been dealt with, the API specifies that the same C function call be made, passing the pointer to the original struct, so that the system can resume It excludes terminated threads and threads that have not yet been started.

Availability: Windows, systems with POSIX threads. Are illegal immigrants more likely to commit crimes? Note: an awakened thread does not actually return from its wait() call until it can reacquire the lock. You can even trivially wrap a thread function to restart itself on exception or return: def threadwrap(threadfunc): def wrapper(): while True: try: threadfunc() except BaseException as e: print('{!r}; restarting thread'.format(e)) else:

All of the methods described below are executed atomically. 16.2.1. Totally Invertible Submatrices Does the code terminate? This is a nonzero integer. but in your case, the for loop is looping over different instances of a thread, each instance being assigned to the variable thread in the loop, so there is no problem