파이썬에서 스레드 만들기

파이썬에서 스레드 만들기

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스크립트가 있는데 한 함수가 다른 함수와 동시에 실행되기를 원합니다.

내가 본 예제 코드 :

import threading

def MyThread (threading.thread):
    # doing something........

def MyThread2 (threading.thread):
    # doing something........

MyThread().start()
MyThread2().start()

이 작업을 수행하는 데 문제가 있습니다. 클래스가 아닌 스레드 함수를 사용 하여이 작업을 선호합니다.

이것은 작동하는 스크립트입니다.

from threading import Thread

class myClass():

    def help(self):
        os.system('./ssh.py')

    def nope(self):
        a = [1,2,3,4,5,6,67,78]
        for i in a:
            print i
            sleep(1)


if __name__ == "__main__":
    Yep = myClass()
    thread = Thread(target = Yep.help)
    thread2 = Thread(target = Yep.nope)
    thread.start()
    thread2.start()
    thread.join()
    print 'Finished'

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Thread이 작업을 수행하기 위해 서브 클래스를 사용할 필요가 없습니다. 아래에 게시하는 간단한 예제를 살펴보고 방법을 확인하십시오.

from threading import Thread
from time import sleep

def threaded_function(arg):
    for i in range(arg):
        print("running")
        sleep(1)


if __name__ == "__main__":
    thread = Thread(target = threaded_function, args = (10, ))
    thread.start()
    thread.join()
    print("thread finished...exiting")

여기에서는 스레딩 모듈을 사용하여 일반 함수를 대상으로 호출하는 스레드를 만드는 방법을 보여줍니다. 스레드 생성자에서 필요한 인수를 전달하는 방법을 알 수 있습니다.

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코드에 몇 가지 문제가 있습니다.

def MyThread ( threading.thread ):

• 함수로 서브 클래 싱 할 수 없습니다. 수업 만
• 서브 클래스를 사용하려고한다면 threading.thread가 아니라 threading을 원할 것입니다.

If you really want to do this with only functions, you have two options:

With threading:

import threading
def MyThread1():
    pass
def MyThread2():
    pass

t1 = threading.Thread(target=MyThread1, args=[])
t2 = threading.Thread(target=MyThread2, args=[])
t1.start()
t2.start()

With thread:

import thread
def MyThread1():
    pass
def MyThread2():
    pass

thread.start_new_thread(MyThread1, ())
thread.start_new_thread(MyThread2, ())

Doc for thread.start_new_thread

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I tried to add another join(), and it seems worked. Here is code

from threading import Thread
from time import sleep

def function01(arg,name):
for i in range(arg):
    print(name,'i---->',i,'\n')
    print (name,"arg---->",arg,'\n')
    sleep(1)


def test01():
    thread1 = Thread(target = function01, args = (10,'thread1', ))
    thread1.start()
    thread2 = Thread(target = function01, args = (10,'thread2', ))
    thread2.start()
    thread1.join()
    thread2.join()
    print ("thread finished...exiting")



test01()

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You can use the target argument in the Thread constructor to directly pass in a function that gets called instead of run.

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Did you override the run() method? If you overrided __init__, did you make sure to call the base threading.Thread.__init__()?

After starting the two threads, does the main thread continue to do work indefinitely/block/join on the child threads so that main thread execution does not end before the child threads complete their tasks?

And finally, are you getting any unhandled exceptions?

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Python 3 has the facility of Launching parallel tasks. This makes our work easier.

It has for thread pooling and Process pooling.

The following gives an insight:

ThreadPoolExecutor Example

import concurrent.futures
import urllib.request

URLS = ['http://www.foxnews.com/',
        'http://www.cnn.com/',
        'http://europe.wsj.com/',
        'http://www.bbc.co.uk/',
        'http://some-made-up-domain.com/']

# Retrieve a single page and report the URL and contents
def load_url(url, timeout):
    with urllib.request.urlopen(url, timeout=timeout) as conn:
        return conn.read()

# We can use a with statement to ensure threads are cleaned up promptly
with concurrent.futures.ThreadPoolExecutor(max_workers=5) as executor:
    # Start the load operations and mark each future with its URL
    future_to_url = {executor.submit(load_url, url, 60): url for url in URLS}
    for future in concurrent.futures.as_completed(future_to_url):
        url = future_to_url[future]
        try:
            data = future.result()
        except Exception as exc:
            print('%r generated an exception: %s' % (url, exc))
        else:
            print('%r page is %d bytes' % (url, len(data)))

Another Example

import concurrent.futures
import math

PRIMES = [
    112272535095293,
    112582705942171,
    112272535095293,
    115280095190773,
    115797848077099,
    1099726899285419]

def is_prime(n):
    if n % 2 == 0:
        return False

    sqrt_n = int(math.floor(math.sqrt(n)))
    for i in range(3, sqrt_n + 1, 2):
        if n % i == 0:
            return False
    return True

def main():
    with concurrent.futures.ThreadPoolExecutor(max_workers=5) as executor:
        for number, prime in zip(PRIMES, executor.map(is_prime, PRIMES)):
            print('%d is prime: %s' % (number, prime))

if __name__ == '__main__':
    main()

참고URL : https://stackoverflow.com/questions/2905965/creating-threads-in-python