Python——管道通信

管道：双向通信 2个进程之间相互通信

 from multiprocessing import Pipe,Process

 def func(conn1,conn2):
     conn2.close()
     while True:
         try :
             msg = conn1.recv()
             print(msg)
         except EOFError:  #抛出无数据时异常
             conn1.close()
             break

 if __name__ == '__main__':
     conn1, conn2 = Pipe()
     Process(target=func,args = (conn1,conn2)).start()
     conn1.close()
     for i in range(20):
         conn2.send('吃了么')
     conn2.close()

实例

利用管道解决消费者模式

  from multiprocessing import Lock,Pipe,Process
  def producer(con,pro,name,food):
      con.close()
      for i in range(100):
          f = '%s生产%s%s'%(name,food,i)
          print(f)
          pro.send(f)
      pro.send(None)
      pro.send(None)
      pro.send(None)
      pro.close()

  def consumer(con,pro,name,lock):
      pro.close()
      while True:
              lock.acquire()
              food = con.recv()
              lock.release()
              if food is None:
                  con.close()
                  break
              print('%s吃了%s' % (name, food))
  if __name__ == '__main__':
      con,pro = Pipe()
      lock= Lock()
      p = Process(target=producer,args=(con,pro,'egon','泔水'))
      c1 = Process(target=consumer, args=(con, pro, 'alex',lock))
      c2 = Process(target=consumer, args=(con, pro, 'bossjin',lock))
      c3 = Process(target=consumer, args=(con, pro, 'wusir',lock))
      c1.start()
      c2.start()
      c3.start()
      p.start()
      con.close()
      pro.close()

  from multiprocessing import Process,Pipe,Lock

  def consumer(produce, consume,name,lock):
      produce.close()
      while True:
          lock.acquire()
          baozi=consume.recv()
          lock.release()
          if baozi:
              print('%s 收到包子:%s' %(name,baozi))
          else:
              consume.close()
              break
 #
  def producer(produce, consume,n):
      consume.close()
      for i in range(n):
          produce.send(i)
      produce.send(None)
      produce.send(None)
      produce.close()
 #
  if __name__ == '__main__':
      produce,consume=Pipe()
      lock = Lock()
      c1=Process(target=consumer,args=(produce,consume,'c1',lock))
      c2=Process(target=consumer,args=(produce,consume,'c2',lock))
      p1=Process(target=producer,args=(produce,consume,30))
      c1.start()
      c2.start()
      p1.start()
      produce.close()
      consume.close()

 # pipe 数据不安全性
 # IPC
 # 加锁来控制操作管道的行为 来避免进程之间争抢数据造成的数据不安全现象

 # 队列 进程之间数据安全的
 # 管道 + 锁

例子