Python 进程之间共享数据(全局变量)
进程之间共享数据(数值型)：
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import multiprocessing -
def func(num): -
num.value=10.78 #子进程改变数值的值，主进程跟着改变 -
if __name__=="__main__": -
num=multiprocessing.Value("d",10.0) # d表示数值,主进程与子进程共享这个value。（主进程与子进程都是用的同一个value） -
print(num.value) -
p=multiprocessing.Process(target=func,args=(num,)) -
p.start() -
p.join() -
print(num.value)
def worker(num, mystr, arr):
num.value *= 2
mystr.value = "ok"
for i in range(len(arr)):
arr[i] = arr[i] * (-1) + 1.5
def dump_vars(num, mystr, arr):
print 'num: ', num.value
print 'str: ', mystr[:]
print 'arr: ', arr[:]
if __name__=='__main__':
num = Value('i', 5)
mystr = Array('c', 'just for test')
arr = Array('d', [1.0, 1.5, -2.0])
dir(str)
print 'init value'
dump_vars(num, mystr, arr)
ps = [Process(target=worker, args=(num, mystr, arr)) for x in range(3)]
for p in ps:
p.start()
for p in ps:
p.join()
print
print 'after all workers finished'
dump_vars(num, mystr, arr)
进程之间共享数据(数组型)：
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import multiprocessing -
def func(num): -
num[2]=9999 #子进程改变数组，主进程跟着改变 -
if __name__=="__main__": -
num=multiprocessing.Array("i",[1,2,3,4,5]) #主进程与子进程共享这个数组 -
print(num[:]) -
p=multiprocessing.Process(target=func,args=(num,)) -
p.start() -
p.join() -
print(num[:])
进程之间共享数据(dict,list)：
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import multiprocessing -
def func(mydict,mylist): -
mydict["index1"]="aaaaaa" #子进程改变dict,主进程跟着改变 -
mydict["index2"]="bbbbbb" -
mylist.append(11) #子进程改变List,主进程跟着改变 -
mylist.append(22) -
mylist.append(33) -
if __name__=="__main__": -
with multiprocessing.Manager() as MG: #重命名 -
mydict=multiprocessing.Manager().dict() #主进程与子进程共享这个字典 -
mylist=multiprocessing.Manager().list(range(5)) #主进程与子进程共享这个List -
p=multiprocessing.Process(target=func,args=(mydict,mylist)) -
p.start() -
p.join() -
print(mylist) -
print(mydict)