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Why is this sending so many variables?

I have created a function timeout_func that will run an another function normally and return its output, but if the function exceeds 'secs' it will return a string 'failed'. Basically, it's a workaround to timeout a function which could run infinitely. (python 2.7 on windows) (Why do I need a workaround, why can't I just make the function non-infinite? Because sometimes you ju开发者_JAVA技巧st can't do that, it' called bugs in known processes ie: fd = os.open('/dev/ttyS0', os.O_RDWR)

Anyways, my timeout_func was inspired from help I received here: kill a function after a certain time in windows

The problem with my code is that for some reason the do_this function is receiving 14 variables instead of one. I get the error msg when running it by double clicking the script or from python.exe. From IDLE you get no exception errors....

Why is this sending so many variables?

However, if I change it to:

def do_this(bob, jim):
return bob, jim

It works just fine...

What's going on here? It doesn't like the 1 variable functions...?

import multiprocessing
import Queue


def wrapper(queue, func, func_args_tuple):
    result = func(*func_args_tuple)
    queue.put(result)
    queue.close()

def timeout_func(secs, func, func_args_tuple):
    queue = multiprocessing.Queue(1) # Maximum size is 1
    proc = multiprocessing.Process( target=wrapper, args=(queue, func, func_args_tuple) )
    proc.start()

    # Wait for TIMEOUT seconds
    try:
        result = queue.get(True, secs)
    except Queue.Empty:
        # Deal with lack of data somehow
        result = 'FAILED'
        print func_args_tuple
    finally:
        proc.terminate()

    return result


def do_this(bob):
    return bob

if __name__ == "__main__":
    print timeout_func( 10, do_this, ('i was returned') )
    x = raw_input('done')


('i was returned') is not a tuple. It evaluates to a string, just like (3+2) evaluated to an integer..

Calling do_this(*('i was returned')) passes each letter of the sequence 'i was returned' as a separate argument - the equivalent of:

do_this('i', ' ', 'w', 'a', 's', ' ', 'r', 'e', 't', 'u', 'r', 'n', 'e', 'd')

Use ('i was returned',) instead to force it to be a tuple (due to the trailing comma).

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