Re: Is there a better way to implement this:
Paul Boddie wrote: Michael Yanowitz wrote: I guess I am looking for something portable (both Windows and Linux) where I can abort a function after a certain time limit expires. Doing a search for timeout function Python on Google reveals a number of approaches. Using threads: * http://aspn.activestate.com/ASPN/Cookbook/Python/Recipe/473878 That doesn't abort the calculation, however -- it just moves on with a default value instead of the actual result if that is not available after the specified timespan. The calculation may go on forever eating up resources. Peter -- http://mail.python.org/mailman/listinfo/python-list
Re: Is there a better way to implement this:
Michael Yanowitz wrote: Hello: I wrote the code below (much irrelevant code removed). This doesn't quite work. What I wanted it to do was a) Execute function ftimed, which takes a function and a timeout in seconds. b) This will also execute function abort() as a thread. This function just runs for the specified number of seconds and returns. However, before it returns, throws an exception. c) If test() is still running when abort() is finished, ftimed() should catch the exception and return. It is catching the exception, however it continues running the function. Why does it continue and not return? The exception is raised in the thread that executes the abort() function. The exception does not get caught and terminates this thread. The other (main) thread is unaffected - exceptions are local to a thread and there is currently no (portable) way to raise an exception in another thread. What am I missing, or is there a better way to implement this (having ftimed() return when the abort-timer time is exceeded? You may use the signal.alarm() function, if you are on a UNIXoid system and you have only a signle time-out at a time (e.g. not nested). import time, thread, sys thread_finished = MAX RUN TIME EXCEEDED! def abort (seconds): start_time = time.time() while ((time.time() - start_time) seconds): time.sleep(0.01) any reason for not using time.sleep(seconds) here? print script run time exceeded max_run_time of, seconds, seconds. raise thread_finished return def test(): i = 0 while (True): time.sleep(1) print HELLO, i i+=1 def ftimed (func, seconds): thread.start_new_thread (abort, (seconds,)) try: func() except thread_finished: print Timeout return ftimed (test, 30) print Script finished -- Benjamin Niemann Email: pink at odahoda dot de WWW: http://pink.odahoda.de/ -- http://mail.python.org/mailman/listinfo/python-list
RE: Is there a better way to implement this:
Thanks. I suppose I could have used time.sleep(seconds) here. I did it in 0.01 because in an earlier verion, I did something else between the sleeps. I guess I am looking for something portable (both Windows and Linux) where I can abort a function after a certain time limit expires. -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Behalf Of Benjamin Niemann Sent: Monday, January 22, 2007 11:19 AM To: python-list@python.org Subject: Re: Is there a better way to implement this: Michael Yanowitz wrote: Hello: I wrote the code below (much irrelevant code removed). This doesn't quite work. What I wanted it to do was a) Execute function ftimed, which takes a function and a timeout in seconds. b) This will also execute function abort() as a thread. This function just runs for the specified number of seconds and returns. However, before it returns, throws an exception. c) If test() is still running when abort() is finished, ftimed() should catch the exception and return. It is catching the exception, however it continues running the function. Why does it continue and not return? The exception is raised in the thread that executes the abort() function. The exception does not get caught and terminates this thread. The other (main) thread is unaffected - exceptions are local to a thread and there is currently no (portable) way to raise an exception in another thread. What am I missing, or is there a better way to implement this (having ftimed() return when the abort-timer time is exceeded? You may use the signal.alarm() function, if you are on a UNIXoid system and you have only a signle time-out at a time (e.g. not nested). import time, thread, sys thread_finished = MAX RUN TIME EXCEEDED! def abort (seconds): start_time = time.time() while ((time.time() - start_time) seconds): time.sleep(0.01) any reason for not using time.sleep(seconds) here? I suppose I could have, but in earlier versions print script run time exceeded max_run_time of, seconds, seconds. raise thread_finished return def test(): i = 0 while (True): time.sleep(1) print HELLO, i i+=1 def ftimed (func, seconds): thread.start_new_thread (abort, (seconds,)) try: func() except thread_finished: print Timeout return ftimed (test, 30) print Script finished -- Benjamin Niemann Email: pink at odahoda dot de WWW: http://pink.odahoda.de/ -- http://mail.python.org/mailman/listinfo/python-list -- http://mail.python.org/mailman/listinfo/python-list
Re: Is there a better way to implement this:
Michael Yanowitz wrote: I guess I am looking for something portable (both Windows and Linux) where I can abort a function after a certain time limit expires. Doing a search for timeout function Python on Google reveals a number of approaches. Using signals: * http://nick.vargish.org/clues/python-tricks.html * http://aspn.activestate.com/ASPN/Cookbook/Python/Recipe/307871 Using threads: * http://aspn.activestate.com/ASPN/Cookbook/Python/Recipe/473878 Using processes: * http://lfw.org/python/delegate.html Paul -- http://mail.python.org/mailman/listinfo/python-list
