进程锁

import json
import time
from multiprocessing import Process
from multiprocessing import Lock

def show(i):
    with open('ticket',encoding='utf-8') as f:
        dic= json.load(f)
    print('余票：%i'%dic['ticket'])



def buy_ticket(i,lock):
    lock.acquire()                  #锁的开启
    with open('ticket',encoding='utf-8') as f:
        dic=json.load(f)
        time.sleep(0.1)
    if dic['ticket']>0:
        dic['ticket'] -= 1
        print('33[32m%s买到票了33[0m'%i)
    else:
        print('33[31m%s没买到票33[0m'%i)
    time.sleep(0.1)
    with open('ticket','w') as f:
        json.dump(dic,f)
    lock.release()               #释放锁

if __name__=='__main__':
    for i in range(10):
        p=Process(target = show,args=(i,))
        p.start()
    lock =Lock()                   #锁的定义
    for i in range(10):
        p=Process(target= buy_ticket,args=(i,lock))    # 锁的传入
        p.start()