Python多进程同步Lock、Semaphore、Event实例

同步的方法基本与多线程相同。

1) Lock

当多个进程需要访问共享资源的时候，Lock可以用来避免访问的冲突。


import multiprocessing
import sys

def worker_with(lock, f):

with lock:

fs = open(f,"a+")

fs.write('Lock acquired via with\n')

fs.close()

def worker_no_with(lock, f):

lock.acquire()

try:

fs = open(f,"a+")

fs.write('Lock acquired directly\n')

fs.close()

finally:

lock.release()

if __name__ == "__main__":

f = "file.txt"

lock = multiprocessing.Lock()

w = multiprocessing.Process(target=worker_with, args=(lock, f))

nw = multiprocessing.Process(target=worker_no_with, args=(lock, f))

w.start()

nw.start()

w.join()

nw.join()