Multiprocessing can only join a started process [closed]

Question

I have the following Python code

jobs = []
p = Process(target=self.verify_process, args=(vm_ha1, creds, run_cmd_ha1, ip_ha1))
jobs.append(p)
p.start()
p = Process(target=self.verify_process, args=(vm_ha2, creds, run_cmd_ha2, ip_ha2))
jobs.append(p)
p.start
p = Process(target=self.verify_process, args=(vm_client, creds, run_cmd_client, ip_client))
jobs.append(p)
p.start
for p in jobs:
    p.join()

The target is a small def checking if a process on a VM has finished, and will print the exit code.

When this is running, I get an error after the first process is finished, and writing its output

  File "/usr/lib/python2.7/multiprocessing/process.py", line 144, in join
    assert self._popen is not None, 'can only join a started process'
AssertionError: can only join a started process

When I was looking around for this, I found a few mentions of this. And most of them were because they were all using p.run() and should use p.start().

But I'm using p.start() already.

This is the first time I'm tying out Multiprocessing, so it is possible I'm using it incorrectly.

From what I can see all 3 processes should be started.

Answer 1

You forgot the parenthesis for the second and third p.start. It should be:

p.start()