进程之锁,信息量,事件,队列,生产者消费者模型,joinablequeue

#锁
import os ,random,time,json
from multiprocessing import Process,Lock
def qiangPiao(i):
    with open('ticket','r+',encoding='utf-8')as f:
        ticket_info_dic=json.load(f)
        if ticket_info_dic['count']>0:
            ticket_info_dic['count']-=1
            # f.write(json.dumps(ticket_info_dic))
            f.seek(0)
            json.dump(ticket_info_dic,f)
            print('"id":%s "i:"%s 抢到票了 '%(os.getpid(),i))
        else:
            print('%s没票了'%i)

class myProcess(Process):
    def __init__(self,i,lock):
        super().__init__()
        self.i=i
        self.lock=lock

    def run(self):
        time.sleep(random.random())
        self.lock.acquire()
        qiangPiao(self.i)
        self.lock.release()


if __name__ == '__main__':
    with open('ticket','w',encoding='utf-8')as f:
        f.write('{"count":1}')
    lock=Lock()
    for i in range(9):
        p=myProcess(i,lock)
        p.start()