Multiprocessing With Delay Of Second Function

I have a function that write data to a text file, a second function that pull data from the same text file and show a graph. I want to start the second function a few seconds after

Solution 1:

You want to use the multiprocessing.Queue

For example (from the docs):

from multiprocessing import Process, Queue

def f(q):
    q.put([42, None, 'hello'])

if __name__ == '__main__':
    q = Queue()
    p = Process(target=f, args=(q,))
    p.start()
    print q.get()    # prints "[42, None, 'hello']"
    p.join()

You could use that in your code like this:

from multiprocessing import Process, Queue
import time


defwriting(q):
    keep_running = True
    numentries = 0
    key = 'something, I assume'for text in get_all(newlista, "sentence", "text"):
        # Python lets you do nice comparisons like this,# which do what they look like. And make it more# obvious that you only want lines of length between# 80 and 500 charactersif80 < len(text) < 500:
            firstword = key.lower().split(None, 1)[0]
            if text.lower().startswith(firstword):               
                # Note: it is *essential* that in `on_data(text)`# after writing to your file you run `file.flush()`# or close the file, otherwise the data *may* be# buffered and hence, missing, when you go to read# the file
                on_data(text)
                q.put(keep_running)

    keep_running = False
    q.put(keep_running)

deflive_graph(q):
    keep_running = Truewhile keep_running:
        keep_running = q.get()
        # do the graph updates hereif __name__=='__main__':
 q = Queue()
 p1 = Process(target = writing, args=(q,))
 p1.start()
 p2 = Process(target = live_graph, args=(q,))
 p2.start()