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How to sharing object between multiple process from main process using Pipe - Subrata - Sep-03-2019
I try to call multiprocessing to act my process faster.
At the moment I face some problems sharing some data with many processes from main process.
I use multiprocess.pipe() to pass the data.
I use multiprocess.manager to pass the data.
1. Initialization:-
<
try:
global devices
self.listofwritetags = self.collectwritetaglist()
conn1, conn2 = multiprocessing.Pipe()
devices = bussiness.initilaztion(self.comm_object,logger)
conn1.send(devices)
self.callmotor1dprocess =
multiprocessing.Process(target=callallmotor1d,args=[conn2])
self.listofthread.append(self.callmotor1dprocess)
2.Start and stop process:-
def startprocess(self):
for item in self.listofprocess:
item.start()
def stopprocess(self):
for item in self.listofprocess:
item.terminate()
UI:-
self.button3 = ttk.Button(self.frame, text='Start', command=self.startprocess,state =NORMAL)
self.button3.grid(column=1, row=4, sticky=W,padx=5, pady=5)
self.button4 = ttk.Button(self.frame, text='Stop', command=self.stopprocess, state=NORMAL)
self.button4.grid(column=1, row=5, sticky=W, padx=5, pady=5)
I need to call avobe 3 process in one class:- FormUI
but I call executable process outside of the FormUI class.
I got an error when I try to initialize.I want to pass devices from main process to child process.
The calling method:-
def callallmotor1d(conn):
devices = conn.recv()
bussiness.motorallprocessing(devices)
def callallsov1s(conn):
devices = conn.recv()
bussiness.motorallprocessing(devices)
Any help regarding this would be appreciable
Error messege:-
2019-09-03 13:15:33,755: can't pickle _thread.lock objects
Traceback (most recent call last):
File "C:/Users/misu01/PycharmProjects/opcua/ui_v7.py", line 226, in initilization
conn1.send(devices)
File "C:\Users\misu01\AppData\Local\Programs\Python\Python37\lib\multiprocessing\connection.py", line 206, in send
self._send_bytes(_ForkingPickler.dumps(obj))
File "C:\Users\misu01\AppData\Local\Programs\Python\Python37\lib\multiprocessing\reduction.py", line 51, in dumps
cls(buf, protocol).dump(obj)
TypeError: can't pickle _thread.lock objects
RE: How to sharing object between multiple process from main process using Pipe - woooee - Sep-03-2019
self.listofprocess has not been declared anywhere in the code you posted
def startprocess(self):
for item in self.listofprocess: