How to stop all processes if one of them changes a global "stop" variable to True

import multiprocessing


global stop
stop = False


def makeprocesses():
    processes = []
    for _ in range(50):
        p = multiprocessing.Process(target=runprocess)
        
        processes.append(p)
    
    for _ in range(50):
        processes[_].start()
    runprocess()


def runprocess():
    global stop
    while stop == False:
        
        x = 1 #do something here

        if x = 1:
            stop = True




makeprocesses()

while stop == True:
    x = 0
    makeprocesses()

How could I make all the other 49 processes stop if just one changes stop to True?
I would think since stop is a global variable once one process changes stop all the others would stop.

>Solution :

No. Each process gets its own copy. It’s global to the script, but not across processes. Remember that each process has a completely separate address space. It gets a COPY of the first process’ data.

If you need to communicate across processes, you need to use one of the synchronization techniques in the multiprocessing documentation (https://docs.python.org/3/library/multiprocessing.html#synchronization-primitives), like an Event or a shared object.